ASN RSS https://amnat.org/ Latest press releases and announcements from the ASN en-us Wed, 20 Mar 2019 05:00:00 GMT 60 Call for Symposium Proposals for ASN 2020 at Asilomar, California 3-7 January https://amnat.org/announcements/CallSympASN2018.html The American Society of Naturalists invites proposals for symposia at its stand-alone meeting at Asilomar, in Monterey, California, 3-7 January 2020. Two symposia will be selected. Symposium topics should support the Society’s goal to advance the conceptual unification of the biological sciences and to further knowledge in evolution, ecology, behavior, and organismal biology. Proposals are encouraged on topics that are synthetic and interdisciplinary, or that address important emerging issues in evolution, ecology, and behavior. Proposals should include (1) a title; (2) a description of the symposium topic (one page); (3) a tentative list of speakers, including institutional affiliations; (4) a justification for the symposium explaining why the topic and speakers are appropriate for an ASN meeting, keeping in mind the broader goals of the society (http://www.amnat.org/about/about-the-society.html); and (5) a statement that all proposed invited speakers have agreed to participate. Organizers should plan the symposia to run from approximately 1:30-5:30 pm, and may allocate this time amongst speakers as they wish, reserving time for a coffee break. Proposals must be submitted by midnight Eastern Standard Time on April 5, 2019 by email to kmkay@ucsc.edu as a single pdf attachment and under the subject heading: ASN Asilomar Symposium Proposal. Proposals that include women, young investigators, and individuals from underrepresented groups are especially encouraged. Please note that, as with previous Asilomar meetings, the society does not have funds to pay for travel or lodging expenses of speakers. However, we may consider requests to waive conference registration costs for junior participants in symposia in cases of financial hardship. Nevertheless, speakers should assume that they will likely have to cover their own travel costs. The Society’s selection committee will evaluate proposals based on the likelihood of attracting a substantial audience, the significance and timeliness of the topic, and on the topic’s differing substantively from recent symposia hosted by the Society. All applicants will be notified of the committee’s decision by late April 2019. Kathleen M. Kay ASN Symposium Committee Chair Department of Ecology and Evolutionary Biology University of California, Santa Cruz kmkay@ucsc.edu &nbsp; &nbsp; <p>The American Society of Naturalists invites proposals for symposia at its stand-alone meeting at Asilomar, in Monterey, California, 3-7 January 2020. Two symposia will be selected.</p> <p>Symposium topics should support the Society&rsquo;s goal to advance the conceptual unification of the biological sciences and to further knowledge in evolution, ecology, behavior, and organismal biology. Proposals are encouraged on topics that are synthetic and interdisciplinary, or that address important emerging issues in evolution, ecology, and behavior.</p> <p>Proposals should include (1) a title; (2) a description of the symposium topic (one page); (3) a tentative list of speakers, including institutional affiliations; (4) a justification for the symposium explaining why the topic and speakers are appropriate for an ASN meeting, keeping in mind the broader goals of the society (http://www.amnat.org/about/about-the-society.html); and (5) a statement that all proposed invited speakers have agreed to participate. Organizers should plan the symposia to run from approximately 1:30-5:30 pm, and may allocate this time amongst speakers as they wish, reserving time for a coffee break.</p> <p>Proposals must be submitted by midnight Eastern Standard Time on April 5, 2019 by email to <a href="mailto:kmkay@ucsc.edu">kmkay@ucsc.edu</a> as a single pdf attachment and under the subject heading: ASN Asilomar Symposium Proposal. Proposals that include women, young investigators, and individuals from underrepresented groups are especially encouraged.</p> <p>Please note that, as with previous Asilomar meetings, the society does not have funds to pay for travel or lodging expenses of speakers. However, we may consider requests to waive conference registration costs for junior participants in symposia in cases of financial hardship. Nevertheless, speakers should assume that they will likely have to cover their own travel costs.</p> <p>The Society&rsquo;s selection committee will evaluate proposals based on the likelihood of attracting a substantial audience, the significance and timeliness of the topic, and on the topic&rsquo;s differing substantively from recent symposia hosted by the Society. All applicants will be notified of the committee&rsquo;s decision by late April 2019.</p> <p>Kathleen M. Kay<br /> ASN Symposium Committee Chair<br /> Department of Ecology and Evolutionary Biology<br /> University of California, Santa Cruz<br /> <a href="http://kmkay@ucsc.edu">kmkay@ucsc.edu</a></p> <p>&nbsp;</p> <p>&nbsp;</p> Tue, 19 Mar 2019 05:00:00 GMT ASN Election https://amnat.org/announcements/ASNElections.html The ASN 2019 Elections are underway for tha offices of President, Vice President, and Treasurer. The election website randomizes the order for each person voting, but the names below are in alphabetical order.The PRESIDENT leads the ASN Executive Council and selects the membership of the award and officer nomination committees. The President selects the President’s Award for the “best” paper in The American Naturalist in the past year, gives the ASN Presidential Address and presents the Society’s awards at the annual meeting, and represents the ASN in multiple other ways through the year. The President serves on the Executive Council for five years, including one year as President-Elect and three years as a Past-President. Susan Alberts For me, the American Society of Naturalists holds a special place in the biological sciences, as the oldest society in the world that advances knowledge in the three fields that my work most intersects with: behavior, evolution, and ecology. The cross-disciplinary nature of the society and the high quality of its journal, the American Naturalist, make it a big-tent society where ideas can collide and grow. The role of the society in bringing together these fields represents an enormous opportunity for fostering connectivity across disciplines. I particularly welcome the opportunity to foster ASN’s international profile and its inclusivity of diverse communities, and to contribute to its work in policy. I’m a Professor of Biology at Duke University, and as of 2016 I’m also a Professor of Evolutionary Anthropology and Chair of the Evolutionary Anthropology Department at Duke. I’ve spent 35 years studying wild primates in Kenya as part of the Amboseli Baboon Research Project, based in southern Kenya. I also studied the socioecology of African elephants for 10 years, publishing work on female and male social relationships and mating behavior, and ecological predictors of elephant group dynamics. I received my PhD from University of Chicago, and did postdocs at University of Chicago and Harvard. I’m a Fellow of the American Association for the Advancement of Science and the American Academy of Arts & Sciences. I’ve not been active in the governance of the ASN but have participated in ASN committees, including chairing the E.O. Wilson Award committee in 2017. I’m proud to be a Lifetime Member of the ASN, and I value the opportunity to run for President of the Society. Edmund "Butch" Brodie III I am an evolutionary biologist with wide interests in genetics, behavior, and natural history. I am especially intrigued by how interactions, whether between species, individuals, or genes, alter the evolutionary process from simpler linear predictions. My current work includes integrative approaches to understanding local adaptation within the molecular and geographic landscapes of predator-prey arms races, and a long-term project that explores the connections between social behavior, indirect genetic effects, and multilevel selection in natural populations of forked fungus beetles. I learned the fun (and power) of combining theory, empiricism, and fieldwork through my PhD training at the University of Chicago and a Miller Fellowship at UC Berkeley’s Museum of Vertebrate Zoology. From there, I moved to faculty positions at University of Kentucky and Indiana University before landing in my current position as BFD Runk Professor of Botany and Director of the Mountain Lake Biological Station at the University of Virginia. The ASN has been instrumental in my professional development since graduate school when I published my first American Naturalist paper. In 1992, I was awarded an ASN Young Investigator Prize and got to coauthor a paper selected for the Presidential Award in 2002. The recognition that has meant the most to me in my career was the 2017 E.O. Wilson Naturalist Award. I was an associate editor of The American Naturalist for 17 years before becoming the current Natural History Miscellany Editor. I happily continue to serve the American Naturalist because it is the most thoughtful and efficient journal board and office of the seven publications I have worked with over the years. I worked indirectly with the ASN council during my two terms as the Executive Vice President of the Society for the Study of Evolution. Through that service and the Joint Council, I was able to promote a number of initiatives that expanded student governance, established a code of conduct for Evolution meeting attendees, launched a new journal (Evolution Letters), and provided a variety of new direct benefits to SSE membership. As president of ASN, my main priorities would include expanding student membership, establishing formal networking opportunities to connect junior and senior members, and keeping natural history in the American Society of Naturalists The VICE-PRESIDENT organizes the Vice-President’s Symposium for the annual meeting and edits the special supplement to The American Naturalist that contains the papers derived from the VP Symposium. The Vice-President is also the Society’s liaison for the organizers of the annual meeting. The Vice-President serves as a member of the Executive Council for three years, two as a regular member and one as ex officio member.&nbsp; Suzanne Alonzo My research uses a combination of mathematical theory and empirical work on fishes to understand how interactions within and between the sexes affect the evolution of social behaviors and reproductive traits. I am particularly interestedin how variation among individuals is maintained, how and why plasticity evolves, and how both affect evolutionary dynamics and reproductive patterns. I am currently a Full Professor in the Department of Ecology and Evolutionary Biology at the University of California Santa Cruz, before which I spent ten years as a professor at Yale University. I did all of my training in the University of California system, including a B.A. from Berkeley, a Ph.D. from UC Santa Barbara and a NSF Postdoctoral Fellowship in Santa Cruz. The most meaningful awards of my career are my graduate and postdoctoral mentorship prizes, for which my research group nominated me. I was also honored to receive the NSF CAREER award and to have been invited to be a plenary speaker at various meetings (e.g. ISBE, ASAB, EEEF, MMEE). I am currently on the executive council for the International Society for Behavioral Ecology and have served as an associate editor for the American Naturalist, Behavioral Ecology, Evolutionary Ecology, Ecology and Evolution, and as associate editor and as editor for the Proceedings of the Royal Society. I am also involved in various activities related to improving science education and increasing inclusion and equity in our classrooms and in our field.&nbsp; I have been member of ASN since I was a first-year graduate student and have served on the journal’s editorial board and on the society’s nominations committee. As I am an evolutionary biologist and a behavioral ecologist, I think of the American Naturalist as "my" journal and society because it is one of the few places where theory, data, evolution, ecology and behavior all come together so naturally and with such excellence. &nbsp; Loren Rieseberg My lab uses a combination of evolutionary genomic approaches and field and greenhouse experiments to understand the origin and evolution of new species, crops, and weeds, focusing on members of the sunflower family.&nbsp;&nbsp;I am especially interested in the roles of hybridization and chromosomal rearrangements in evolution.&nbsp;&nbsp;&nbsp; I received my PhD in Botany from Washington State University in 1987 and subsequently took positions at the Rancho Santa Ana Botanical Garden (until 1993), Indiana University (until 2006), and at the University of British Columbia, where I am a University Killam Professor and Canada Research Chair in Plant Evolutionary Genomics.&nbsp;My work has been recognized by MacArthur and Guggenheim Fellowships, the David Starr Jordan Prize, Stebbins Medal, and the Darwin-Wallace Medal.&nbsp;I am an elected fellow of the Royal Societies of London and Canada, the Norwegian Academy of Arts and Letters, and the American Academy of Arts and Sciences.&nbsp; I have served on the Council for the American Genetics Association and the Steering Committee for the Biological Sciences Section at AAAS.&nbsp;I am a past-President of the American Genetics Association and the Botanical Society of America, and have served as Chief Editor of Molecular Ecology since 1999.&nbsp;At UBC, I have served as Director of the Biodiversity Research Centre (a cross-UBC community of 66 researchers representing ten academic units) since 2016. Although I have not previously served the ASN, I have spoken at ASN symposia and published frequently in The American Naturalist.&nbsp;I also worked closely with other journal editors to promote data archiving in evolutionary biology and ecology, and to implement these policies in a practical way in The American Naturalist and other evolution and ecology journals.&nbsp; I am interested in working with the ASN to address current challenges facing scientific journals and the societies they fund.&nbsp;Possible areas I would consider for the VP symposium include evolutionary agriculture, invasion evolutionary ecology, and structural variation and evolution.&nbsp; The TREASURER manages the accounts of the ASN, tracks all revenues and expenses, arranges for official annual financial reviews and tax return preparation, files tax returns, makes payments for all annual awards and travel reimbursements related to the annual meeting, keeps track of revisions to the award amounts and reimbursement policies, and prepares the annual Treasurer’s Report. The Treasurer also convenes a Finance Committee comprised of two other members of the Executive Council, for making investment decisions as needed. The Treasurer serves on the Executive Council for six years, three as a regular member and three as Past Treasurer. Vote to approve or disapprove. Rebecca "Becky" Fuller My research focuses broadly on evolution in fishes.&nbsp;Half of our work focuses on the evolution of color patterns, color vision, and phenotypic plasticity in these traits as a function of spatial and temporal variation in lighting environments and the subsequent effects on sexual and natural selection. The other half of our work focuses on speciation in fishes (both darters and killifish) due to the effects of reinforcement, genomic rearrangements, and ecological selection. I obtained a B.S. from the University of Nebraska, studied at Uppsala University in Sweden under a Fulbright Scholarship, obtained an M.S. from Michigan State University, a Ph.D. from Florida State University, and started as an assistant professor at the University of Illinois in 2005.&nbsp;I was a recipient of the ASN Young Investigator Award, an NSF Career Award, and several awards for research and teaching excellence at the University of Illinois. In addition to my service to the American Naturalist (see below), I have served in leadership roles at the University of Illinois and also at the Society for the Study of Evolution.&nbsp;At UI, I serve as our Director of Graduate Studies for my department, I co-organize our seminar on Ecology and Evolution (with Dr. Katy Heath), I serve on our School&#39;s Executive Committee, and I serve on the Executive Committee of the Graduate College.&nbsp;At SSE, I have served as a society councilor, served as an Associate Editor at Evolution, served on the Evolution Education committee, and have helped organize several student award competitions.&nbsp; I have served the American Society of Naturalists in several ways.&nbsp;I helped Dan Bolnick organize the first standalone meeting at Asilomar, served on the Student Research Awards committee for 3 years with one year as the chair, served as the society representative to the Joint Meeting Committee that helps organize the tri-society meeting in the summer (&#39;Evolution Meetings&#39;) for 2 years, and served as an Associate Editor at our journal, The American Naturalist. I helped co-organize a symposium that was focused on using natural history in the classroom with George Gilchrist, and I organized a spotlight symposium focusing on &#39;25 Years of Sensory Drive&#39;. I am honored to be considered for the role of treasurer at the American Naturalist.&nbsp;The basic role of the treasurer is (a) to oversee the bank accounts of the society, (b) to make certain that bills, award checks, and associated paperwork are issued in a reasonable amount of time, (c) to make certain that taxes are filed on time, and (d) to act as a basic watchdog over the society&#39;s finances.&nbsp;My relevant experience in this area comes from my start-up company, "BassInSight" which makes software that mimics the visual experience of largemouth bass. My relevant experience involves making certain that the company does not overspend its accounts and submits its tax forms on time. <p>The ASN 2019 Elections are underway for tha offices of President, Vice President, and Treasurer. The election website randomizes the order for each person voting, but the names below are in alphabetical order.</p><p>The PRESIDENT leads the ASN Executive Council and selects the membership of the award and officer nomination committees. The President selects the President&rsquo;s Award for the &ldquo;best&rdquo; paper in The American Naturalist in the past year, gives the ASN Presidential Address and presents the Society&rsquo;s awards at the annual meeting, and represents the ASN in multiple other ways through the year. The President serves on the Executive Council for five years, including one year as President-Elect and three years as a Past-President.</p> <p style="text-align: center;"><strong>Susan Alberts</strong><strong> </strong></p> <p>For me, the American Society of Naturalists holds a special place in the biological sciences, as the oldest society in the world that advances knowledge in the three fields that my work most intersects with: behavior, evolution, and ecology. The cross-disciplinary nature of the society and the high quality of its journal, the American Naturalist, make it a big-tent society where ideas can collide and grow. The role of the society in bringing together these fields represents an enormous opportunity for fostering connectivity across disciplines. I particularly welcome the opportunity to foster ASN&rsquo;s international profile and its inclusivity of diverse communities, and to contribute to its work in policy.</p> <p>I&rsquo;m a Professor of Biology at Duke University, and as of 2016 I&rsquo;m also a Professor of Evolutionary Anthropology and Chair of the Evolutionary Anthropology Department at Duke. I&rsquo;ve spent 35 years studying wild primates in Kenya as part of the Amboseli Baboon Research Project, based in southern Kenya. I also studied the socioecology of African elephants for 10 years, publishing work on female and male social relationships and mating behavior, and ecological predictors of elephant group dynamics. I received my PhD from University of Chicago, and did postdocs at University of Chicago and Harvard. I&rsquo;m a Fellow of the American Association for the Advancement of Science and the American Academy of Arts &amp; Sciences. I&rsquo;ve not been active in the governance of the ASN but have participated in ASN committees, including chairing the E.O. Wilson Award committee in 2017. I&rsquo;m proud to be a Lifetime Member of the ASN, and I value the opportunity to run for President of the Society.</p> <p style="text-align: center;"><strong>Edmund &quot;Butch&quot; Brodie III</strong></p> <p>I am an evolutionary biologist with wide interests in genetics, behavior, and natural history. I am especially intrigued by how interactions, whether between species, individuals, or genes, alter the evolutionary process from simpler linear predictions. My current work includes integrative approaches to understanding local adaptation within the molecular and geographic landscapes of predator-prey arms races, and a long-term project that explores the connections between social behavior, indirect genetic effects, and multilevel selection in natural populations of forked fungus beetles. I learned the fun (and power) of combining theory, empiricism, and fieldwork through my PhD training at the University of Chicago and a Miller Fellowship at UC Berkeley&rsquo;s Museum of Vertebrate Zoology. From there, I moved to faculty positions at University of Kentucky and Indiana University before landing in my current position as BFD Runk Professor of Botany and Director of the Mountain Lake Biological Station at the University of Virginia.</p> <p>The ASN has been instrumental in my professional development since graduate school when I published my first American Naturalist paper. In 1992, I was awarded an ASN Young Investigator Prize and got to coauthor a paper selected for the Presidential Award in 2002. The recognition that has meant the most to me in my career was the 2017 E.O. Wilson Naturalist Award. I was an associate editor of The American Naturalist for 17 years before becoming the current Natural History Miscellany Editor. I happily continue to serve the American Naturalist because it is the most thoughtful and efficient journal board and office of the seven publications I have worked with over the years. I worked indirectly with the ASN council during my two terms as the Executive Vice President of the Society for the Study of Evolution. Through that service and the Joint Council, I was able to promote a number of initiatives that expanded student governance, established a code of conduct for Evolution meeting attendees, launched a new journal (Evolution Letters), and provided a variety of new direct benefits to SSE membership. As president of ASN, my main priorities would include expanding student membership, establishing formal networking opportunities to connect junior and senior members, and keeping natural history in the American Society of Naturalists</p> <hr /><p>The VICE-PRESIDENT organizes the Vice-President&rsquo;s Symposium for the annual meeting and edits the special supplement to <em>The American Naturalist</em> that contains the papers derived from the VP Symposium. The Vice-President is also the Society&rsquo;s liaison for the organizers of the annual meeting. The Vice-President serves as a member of the Executive Council for three years, two as a regular member and one as ex officio member.&nbsp;</p> <p style="text-align: center;"><strong>Suzanne Alonzo</strong></p> <p>My research uses a combination of mathematical theory and empirical work on fishes to understand how interactions within and between the sexes affect the evolution of social behaviors and reproductive traits. I am particularly interestedin how variation among individuals is maintained, how and why plasticity evolves, and how both affect evolutionary dynamics and reproductive patterns.</p> <p>I am currently a Full Professor in the Department of Ecology and Evolutionary Biology at the University of California Santa Cruz, before which I spent ten years as a professor at Yale University. I did all of my training in the University of California system, including a B.A. from Berkeley, a Ph.D. from UC Santa Barbara and a NSF Postdoctoral Fellowship in Santa Cruz. The most meaningful awards of my career are my graduate and postdoctoral mentorship prizes, for which my research group nominated me. I was also honored to receive the NSF CAREER award and to have been invited to be a plenary speaker at various meetings (e.g. ISBE, ASAB, EEEF, MMEE).</p> <p>I am currently on the executive council for the International Society for Behavioral Ecology and have served as an associate editor for the American Naturalist, Behavioral Ecology, Evolutionary Ecology, Ecology and Evolution, and as associate editor and as editor for the Proceedings of the Royal Society. I am also involved in various activities related to improving science education and increasing inclusion and equity in our classrooms and in our field.&nbsp; I have been member of ASN since I was a first-year graduate student and have served on the journal&rsquo;s editorial board and on the society&rsquo;s nominations committee. As I am an evolutionary biologist and a behavioral ecologist, I think of the American Naturalist as &quot;my&quot; journal and society because it is one of the few places where theory, data, evolution, ecology and behavior all come together so naturally and with such excellence. &nbsp;</p> <p style="text-align: center;"><strong>Loren Rieseberg</strong></p> <p>My lab uses a combination of evolutionary genomic approaches and field and greenhouse experiments to understand the origin and evolution of new species, crops, and weeds, focusing on members of the sunflower family.&nbsp;&nbsp;I am especially interested in the roles of hybridization and chromosomal rearrangements in evolution.&nbsp;&nbsp;&nbsp;</p> <p>I received my PhD in Botany from Washington State University in 1987 and subsequently took positions at the Rancho Santa Ana Botanical Garden (until 1993), Indiana University (until 2006), and at the University of British Columbia, where I am a University Killam Professor and Canada Research Chair in Plant Evolutionary Genomics.&nbsp;My work has been recognized by MacArthur and Guggenheim Fellowships, the David Starr Jordan Prize, Stebbins Medal, and the Darwin-Wallace Medal.&nbsp;I am an elected fellow of the Royal Societies of London and Canada, the Norwegian Academy of Arts and Letters, and the American Academy of Arts and Sciences.&nbsp;</p> <p>I have served on the Council for the American Genetics Association and the Steering Committee for the Biological Sciences Section at AAAS.&nbsp;I am a past-President of the American Genetics Association and the Botanical Society of America, and have served as Chief Editor of <em>Molecular Ecology</em> since 1999.&nbsp;At UBC, I have served as Director of the Biodiversity Research Centre (a cross-UBC community of 66 researchers representing ten academic units) since 2016. Although I have not previously served the ASN, I have spoken at ASN symposia and published frequently in <em>The American Naturalist</em>.&nbsp;I also worked closely with other journal editors to promote data archiving in evolutionary biology and ecology, and to implement these policies in a practical way in <em>The American Naturalist </em>and other evolution and ecology journals.&nbsp;</p> <p>I am interested in working with the ASN to address current challenges facing scientific journals and the societies they fund.&nbsp;Possible areas I would consider for the VP symposium include evolutionary agriculture, invasion evolutionary ecology, and structural variation and evolution.&nbsp;</p> <hr /><p>The TREASURER manages the accounts of the ASN, tracks all revenues and expenses, arranges for official annual financial reviews and tax return preparation, files tax returns, makes payments for all annual awards and travel reimbursements related to the annual meeting, keeps track of revisions to the award amounts and reimbursement policies, and prepares the annual Treasurer&rsquo;s Report. The Treasurer also convenes a Finance Committee comprised of two other members of the Executive Council, for making investment decisions as needed. The Treasurer serves on the Executive Council for six years, three as a regular member and three as Past Treasurer. Vote to approve or disapprove.</p> <p style="text-align: center;"><strong>Rebecca &quot;Becky&quot; Fuller</strong></p> <p>My research focuses broadly on evolution in fishes.&nbsp;Half of our work focuses on the evolution of color patterns, color vision, and phenotypic plasticity in these traits as a function of spatial and temporal variation in lighting environments and the subsequent effects on sexual and natural selection. The other half of our work focuses on speciation in fishes (both darters and killifish) due to the effects of reinforcement, genomic rearrangements, and ecological selection.</p> <p>I obtained a B.S. from the University of Nebraska, studied at Uppsala University in Sweden under a Fulbright Scholarship, obtained an M.S. from Michigan State University, a Ph.D. from Florida State University, and started as an assistant professor at the University of Illinois in 2005.&nbsp;I was a recipient of the ASN Young Investigator Award, an NSF Career Award, and several awards for research and teaching excellence at the University of Illinois.</p> <p>In addition to my service to the American Naturalist (see below), I have served in leadership roles at the University of Illinois and also at the Society for the Study of Evolution.&nbsp;At UI, I serve as our Director of Graduate Studies for my department, I co-organize our seminar on Ecology and Evolution (with Dr. Katy Heath), I serve on our School&#39;s Executive Committee, and I serve on the Executive Committee of the Graduate College.&nbsp;At SSE, I have served as a society councilor, served as an Associate Editor at Evolution, served on the Evolution Education committee, and have helped organize several student award competitions.&nbsp;</p> <p>I have served the American Society of Naturalists in several ways.&nbsp;I helped Dan Bolnick organize the first standalone meeting at Asilomar, served on the Student Research Awards committee for 3 years with one year as the chair, served as the society representative to the Joint Meeting Committee that helps organize the tri-society meeting in the summer (&#39;Evolution Meetings&#39;) for 2 years, and served as an Associate Editor at our journal, The American Naturalist. I helped co-organize a symposium that was focused on using natural history in the classroom with George Gilchrist, and I organized a spotlight symposium focusing on &#39;25 Years of Sensory Drive&#39;.</p> <p>I am honored to be considered for the role of treasurer at the American Naturalist.&nbsp;The basic role of the treasurer is (a) to oversee the bank accounts of the society, (b) to make certain that bills, award checks, and associated paperwork are issued in a reasonable amount of time, (c) to make certain that taxes are filed on time, and (d) to act as a basic watchdog over the society&#39;s finances.&nbsp;My relevant experience in this area comes from my start-up company, &quot;BassInSight&quot; which makes software that mimics the visual experience of largemouth bass. My relevant experience involves making certain that the company does not overspend its accounts and submits its tax forms on time.</p> <hr /> Thu, 14 Mar 2019 05:00:00 GMT “Habitat saturation results in joint-nesting female coalitions in a social bird” https://amnat.org/an/newpapers/JuneBarve.html The DOI will be https://dx.doi.org/10.1086/703188 Sisters unite! Acorn woodpecker females joint nest in saturated habitats influencing fitness in both males and females Acorn woodpeckers live in close-knit family groups and have one of the most complex breeding systems of any bird. In about 20% of family groups, up to three related females may lay eggs in a nest together and raise the chicks cooperatively with one or more related males, a behavior known as joint nesting or cooperative polyandry and known in only 0.2% of all bird species. Based on demographic data collected over 35 years (1982-2016) at the Hastings Natural History Reservation in central coastal California, the authors quantified the costs and benefits of joint nesting to attempt to explain why some woodpecker females exhibit this rare behavior. They found that the incidence of joint nesting was more common in years when the population was high, all the breeding territories were occupied, and opportunities for a female to nest on her own very unlikely. Although forming joint nests reduces the number of offspring each female can produce compared to when she nests alone, such females make the “best of a bad situation” by nesting jointly with their mother or sister rather than not nesting at all. Additionally, females that decide to nest jointly do so in groups where there are two or more breeder males, thus increasing the number of caregivers and, hence, the total number of chicks that females can successfully raise. Years of population boom may have therefore been an important mechanism driving the evolution of such highly social behaviors like joint nesting in acorn woodpeckers. Abstract Joint nesting by females and cooperative polyandry—cooperatively breeding groups with a male-biased breeder sex ratio—are little-understood, rare breeding systems. We tested alternative hypotheses of factors potentially driving these phenomena in a population of joint-nesting acorn woodpeckers (Melanerpes formicivorus). During periods of high population density and, thus low independent breeding opportunities, acorn woodpecker females formed joint-nesting coalitions with close kin. Coalitions were typically associated with groups with a male bias. We found strong evidence for both inter- and intra-sexual conflict, as joint nesting conferred a fitness benefit to some males, a significant fitness cost to females, and no gain in per capita reproductive output for either sex. Such conflict, particularly the cost to females, may be an important reason why joint nesting is rare among cooperatively breeding taxa. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703188 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703188">Read the Article</a></i> </p> --> <p><b>Sisters unite! Acorn woodpecker females joint nest in saturated habitats influencing fitness in both males and females </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>corn woodpeckers live in close-knit family groups and have one of the most complex breeding systems of any bird. In about 20% of family groups, up to three related females may lay eggs in a nest together and raise the chicks cooperatively with one or more related males, a behavior known as joint nesting or cooperative polyandry and known in only 0.2% of all bird species. Based on demographic data collected over 35 years (1982-2016) at the Hastings Natural History Reservation in central coastal California, the authors quantified the costs and benefits of joint nesting to attempt to explain why some woodpecker females exhibit this rare behavior. They found that the incidence of joint nesting was more common in years when the population was high, all the breeding territories were occupied, and opportunities for a female to nest on her own very unlikely. Although forming joint nests reduces the number of offspring each female can produce compared to when she nests alone, such females make the “best of a bad situation” by nesting jointly with their mother or sister rather than not nesting at all. Additionally, females that decide to nest jointly do so in groups where there are two or more breeder males, thus increasing the number of caregivers and, hence, the total number of chicks that females can successfully raise. Years of population boom may have therefore been an important mechanism driving the evolution of such highly social behaviors like joint nesting in acorn woodpeckers. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">J</span>oint nesting by females and cooperative polyandry—cooperatively breeding groups with a male-biased breeder sex ratio—are little-understood, rare breeding systems. We tested alternative hypotheses of factors potentially driving these phenomena in a population of joint-nesting acorn woodpeckers (<i>Melanerpes formicivorus</i>). During periods of high population density and, thus low independent breeding opportunities, acorn woodpecker females formed joint-nesting coalitions with close kin. Coalitions were typically associated with groups with a male bias. We found strong evidence for both inter- and intra-sexual conflict, as joint nesting conferred a fitness benefit to some males, a significant fitness cost to females, and no gain in per capita reproductive output for either sex. Such conflict, particularly the cost to females, may be an important reason why joint nesting is rare among cooperatively breeding taxa. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 12 Mar 2019 05:00:00 GMT “Biotic interactions contribute to the geographic range limit of an annual plant: herbivory and phenology mediate fitness beyond a range margin” https://amnat.org/an/newpapers/JuneBenning.html The DOI will be https://dx.doi.org/10.1086/703187 Using multiple lines of evidence, Benning et al. show how biotic interactions can contribute to geographic range limits Palm trees don’t grow in Minnesota, and you won’t find any redwoods in Texas. These limits to species’ distributions are one of the most readily apparent ecological phenomena, but are poorly understood. And as environments change worldwide, conservationists and policy makers increasingly need to know how these environmental changes will affect species distributions. Benning et al. show that for a California endemic plant, herbivory by small mammals may play a large role in setting the plant’s range limit. The researchers have been working with the plant Clarkia xantiana ssp. xantiana for over a decade in the southern Sierra Nevada foothills of California. In a previous experiment where they transplanted seeds outside the range limit in order to see if they could survive there, they noticed that many of the plants were eaten by rabbits and hares. However, plants at the center of the range were rarely eaten. Benning et al. were interested in three main questions: 1) how does the probability of herbivory change going from the center to beyond the range limit; 2) how much does this fatal herbivory lower average fitness in transplanted populations outside the range edge; and 3) is there a specific trait that makes the plant more susceptible to herbivory? Using both field and simulation approaches, they found a sharp increase in herbivory near the range edge, which led to large decreases in fitness outside the range, and found evidence that the slow development of C.&nbsp;x.&nbsp;xantiana exposes it to high rates of herbivory outside its range. Together, these results provide one of the most comprehensive explorations of how biotic interactions can influence large-scale distributions. Abstract Species’ geographic distributions have already shifted during the Anthropocene. However, we often do not know what aspects of the environment drive range dynamics, much less which traits mediate organisms’ responses to these environmental gradients. Most studies focus on possible climatic limits to species’ distributions and have ignored the role of biotic interactions, despite theoretical support for their importance in setting distributional limits. We used field experiments and simulations to estimate contributions of mammalian herbivory to a range boundary in the Californian annual plant Clarkia xantiana ssp. xantiana. A steep gradient of increasing probability of herbivory occurred across the boundary, and a reanalysis of prior transplant experiments revealed that herbivory drove several-fold declines in lifetime fitness at and beyond the boundary. Simulations showed that populations could potentially persist beyond the range margin in the absence of herbivory. Using data from a narrowly sympatric subspecies, C.&nbsp;x.&nbsp;parviflora, we also showed that delayed phenology is strongly associated with C.&nbsp;xantiana ssp. xantiana’s susceptibility to herbivory and low fitness beyond its border. Overall, our results provide some of the most comprehensive evidence to date of how the interplay of demography, traits, and spatial gradients in species interactions can produce a geographic range limit, and lend empirical support to recent developments in range limits theory. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703187 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703187">Read the Article</a></i> </p> --> <p><b>Using multiple lines of evidence, Benning et al. show how biotic interactions can contribute to geographic range limits </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>alm trees don’t grow in Minnesota, and you won’t find any redwoods in Texas. These limits to species’ distributions are one of the most readily apparent ecological phenomena, but are poorly understood. And as environments change worldwide, conservationists and policy makers increasingly need to know how these environmental changes will affect species distributions. Benning et al. show that for a California endemic plant, herbivory by small mammals may play a large role in setting the plant’s range limit. </p><p>The researchers have been working with the plant <i>Clarkia xantiana</i> ssp. <i>xantiana</i> for over a decade in the southern Sierra Nevada foothills of California. In a previous experiment where they transplanted seeds outside the range limit in order to see if they could survive there, they noticed that many of the plants were eaten by rabbits and hares. However, plants at the center of the range were rarely eaten. Benning et al. were interested in three main questions: 1) how does the probability of herbivory change going from the center to beyond the range limit; 2) how much does this fatal herbivory lower average fitness in transplanted populations outside the range edge; and 3) is there a specific trait that makes the plant more susceptible to herbivory? Using both field and simulation approaches, they found a sharp increase in herbivory near the range edge, which led to large decreases in fitness outside the range, and found evidence that the slow development of <i>C.&nbsp;x.&nbsp;xantiana</i> exposes it to high rates of herbivory outside its range. Together, these results provide one of the most comprehensive explorations of how biotic interactions can influence large-scale distributions. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">S</span>pecies’ geographic distributions have already shifted during the Anthropocene. However, we often do not know what aspects of the environment drive range dynamics, much less which traits mediate organisms’ responses to these environmental gradients. Most studies focus on possible climatic limits to species’ distributions and have ignored the role of biotic interactions, despite theoretical support for their importance in setting distributional limits. We used field experiments and simulations to estimate contributions of mammalian herbivory to a range boundary in the Californian annual plant <i>Clarkia xantiana</i> ssp. <i>xantiana</i>. A steep gradient of increasing probability of herbivory occurred across the boundary, and a reanalysis of prior transplant experiments revealed that herbivory drove several-fold declines in lifetime fitness at and beyond the boundary. Simulations showed that populations could potentially persist beyond the range margin in the absence of herbivory. Using data from a narrowly sympatric subspecies, <i>C.&nbsp;x.&nbsp;parviflora</i>, we also showed that delayed phenology is strongly associated with <i>C.&nbsp;xantiana</i> ssp. <i>xantiana</i>’s susceptibility to herbivory and low fitness beyond its border. Overall, our results provide some of the most comprehensive evidence to date of how the interplay of demography, traits, and spatial gradients in species interactions can produce a geographic range limit, and lend empirical support to recent developments in range limits theory. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 12 Mar 2019 05:00:00 GMT “Adaptive differences in circadian clock gene expression patterns and photoperiodic diapause induction in Nasonia vitripennis” https://amnat.org/an/newpapers/JuneDallaBenetta.html The DOI will be https://dx.doi.org/10.1086/703159 Knock down of the clock gene period changes the pace and the phase of the circadian clock and delays diapause response In 2017, the Nobel prize in medicine was awarded for the discovery of the endogenous circadian clock, that enables organisms from bacteria to plants and animals to exhibit biological rhythms adapted to daily (circadian) and annual environmental oscillations. Studies on the genetics of the clock have revealed much complexity and variation. The Marie Skłodowska-Curie Initial Training Network (ITN) INsecTIME was initiated to train early scientists to investigate the (neuro)genetics that underlie biological timing. Here we report variation in circadian clock gene expression patterns in the parasitoid wasp Nasonia vitripennis. This wasp has a photoperiodically induced larval dormancy state called diapause When adult females experience certain critically short daylight conditions, which is dependent on geographical location, they produce diapausing larvae that resume development when conditions are favorable. The study reveals that geographical differences in circadian clock gene regulation under different photoperiods may play a role in regulating this seasonal adaptation. In particular the expression of the clock gene period is important for setting the pace and the phase of Nasonia daily rhythms as well as in the timer mechanism responsible for diapause induction. This shows that genes of the circadian clock are involved in seasonal timing as well, and therefore links the evolution of circadian and circannual adaptive mechanisms. Abstract Day length (photoperiod) and temperature oscillate daily and seasonally and are important cues for season-dependent behavior. Larval diapause of the parasitoid Nasonia vitripennis is maternally induced following a certain number of days (switch point) of a given critical photoperiod (CPP). Both the switch point and CPP follow a latitudinal cline in European N.&nbsp;vitripennis populations. We previously showed that allelic frequencies of the clock gene period correlate with this diapause induction cline. Here, we report that circadian expression of four clock genes, period (per), cryptochrome-2 (cry-2), clock (clk) and cycle (cyc), oscillates as a function of photoperiod and latitude of origin in wasps from populations from the extremes of the cline. Expression amplitudes are lower in northern wasps, indicating a weaker, more plastic, clock. Northern wasps also have a later onset of activity and longer free running rhythms in constant conditions. Per RNAi caused speeding up of the circadian clock, changed the expression of other clock genes and delayed diapause in both southern and northern wasps. These results point towards adaptive latitudinal clock-gene expression differences and to a key role of per in the timing of photoperiodic diapause induction of N.&nbsp;vitripennis. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703159 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703159">Read the Article</a></i> </p> --> <p><b>Knock down of the clock gene period changes the pace and the phase of the circadian clock and delays diapause response </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>n 2017, the Nobel prize in medicine was awarded for the discovery of the endogenous circadian clock, that enables organisms from bacteria to plants and animals to exhibit biological rhythms adapted to daily (circadian) and annual environmental oscillations. Studies on the genetics of the clock have revealed much complexity and variation. The Marie Skłodowska-Curie Initial Training Network (ITN) INsecTIME was initiated to train early scientists to investigate the (neuro)genetics that underlie biological timing. Here we report variation in circadian clock gene expression patterns in the parasitoid wasp <i>Nasonia vitripennis</i>. This wasp has a photoperiodically induced larval dormancy state called diapause When adult females experience certain critically short daylight conditions, which is dependent on geographical location, they produce diapausing larvae that resume development when conditions are favorable. The study reveals that geographical differences in circadian clock gene regulation under different photoperiods may play a role in regulating this seasonal adaptation. In particular the expression of the clock gene <i>period</i> is important for setting the pace and the phase of <i>Nasonia</i> daily rhythms as well as in the timer mechanism responsible for diapause induction. This shows that genes of the circadian clock are involved in seasonal timing as well, and therefore links the evolution of circadian and circannual adaptive mechanisms. <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">D</span>ay length (photoperiod) and temperature oscillate daily and seasonally and are important cues for season-dependent behavior. Larval diapause of the parasitoid <i>Nasonia vitripennis</i> is maternally induced following a certain number of days (switch point) of a given critical photoperiod (CPP). Both the switch point and CPP follow a latitudinal cline in European <i>N.&nbsp;vitripennis</i> populations. We previously showed that allelic frequencies of the clock gene <i>period</i> correlate with this diapause induction cline. Here, we report that circadian expression of four clock genes, <i>period (per), cryptochrome-2 (cry-2), clock (clk)</i> and <i>cycle (cyc)</i>, oscillates as a function of photoperiod and latitude of origin in wasps from populations from the extremes of the cline. Expression amplitudes are lower in northern wasps, indicating a weaker, more plastic, clock. Northern wasps also have a later onset of activity and longer free running rhythms in constant conditions. <i>Per</i> RNAi caused speeding up of the circadian clock, changed the expression of other clock genes and delayed diapause in both southern and northern wasps. These results point towards adaptive latitudinal clock-gene expression differences and to a key role of <i>per</i> in the timing of photoperiodic diapause induction of <i>N.&nbsp;vitripennis</i>. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Fri, 08 Mar 2019 06:00:00 GMT “A practical guide to the study of distribution limits” https://amnat.org/an/newpapers/JuneWilli.html The DOI will be https://dx.doi.org/10.1086/703172 A practical guide to studying distribution limits, emphasizing recently proposed genetic constraints Constraints on adaptation are an important explanation for the tremendous diversity of species on Earth. This may seem surprising – after all, adaptation also leads to the evolution of new species. But adaptive limits prevent species from evolving ever-larger ecological niches, and hence ensure that species are confined to restricted geographic distributions. This, in part, explains why different species occur in different geographic regions. This argument suggests that the causes of range limits are a key to understanding the maintenance of biodiversity. According to theory, there are several plausible explanations for range limits, but empirical tests are too limited to reach any general conclusions. This article is a guide to the study of range limits that should be applicable to any organism. It emphasizes the degradation of habitat quality near the edge of the range, the consequences of small population size and fragmentation at the edge, genetic factors that may obstruct adaptation at the range edge, and the importance of synthesizing different explanations within an eco-evolutionary framework. Abstract Factors that limit the geographic distribution of species are broadly important in ecology and evolutionary biology, and understanding distribution limits is imperative for predicting how species will respond to environmental change. Good data indicate that factors such as dispersal limitation, small effective population size, and isolation are sometimes important. But empirical research highlights no single factor that explains the ubiquity of distribution limits. In this article, we outline a guide to tackling distribution limits that integrates established causes, such as dispersal limitation and spatial environmental heterogeneity, with understudied causes such as mutational load and genetic or developmental integration of traits limiting niche expansion. We highlight how modeling and quantitative genetic and genomic analyses can provide insight into sources of distribution limits. Our practical guide provides a framework for considering the many factors likely to determine species distributions and how the different approaches can be integrated to predict distribution limits using eco-evolutionary modeling. The framework should also help predict distribution limits of invasive species and under climate change. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703172 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703172">Read the Article</a></i> </p> --> <p><b>A practical guide to studying distribution limits, emphasizing recently proposed genetic constraints </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">C</span>onstraints on adaptation are an important explanation for the tremendous diversity of species on Earth. This may seem surprising – after all, adaptation also leads to the evolution of new species. But adaptive limits prevent species from evolving ever-larger ecological niches, and hence ensure that species are confined to restricted geographic distributions. This, in part, explains why different species occur in different geographic regions. This argument suggests that the causes of range limits are a key to understanding the maintenance of biodiversity. According to theory, there are several plausible explanations for range limits, but empirical tests are too limited to reach any general conclusions. This article is a guide to the study of range limits that should be applicable to any organism. It emphasizes the degradation of habitat quality near the edge of the range, the consequences of small population size and fragmentation at the edge, genetic factors that may obstruct adaptation at the range edge, and the importance of synthesizing different explanations within an eco-evolutionary framework. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">F</span>actors that limit the geographic distribution of species are broadly important in ecology and evolutionary biology, and understanding distribution limits is imperative for predicting how species will respond to environmental change. Good data indicate that factors such as dispersal limitation, small effective population size, and isolation are sometimes important. But empirical research highlights no single factor that explains the ubiquity of distribution limits. In this article, we outline a guide to tackling distribution limits that integrates established causes, such as dispersal limitation and spatial environmental heterogeneity, with understudied causes such as mutational load and genetic or developmental integration of traits limiting niche expansion. We highlight how modeling and quantitative genetic and genomic analyses can provide insight into sources of distribution limits. Our practical guide provides a framework for considering the many factors likely to determine species distributions and how the different approaches can be integrated to predict distribution limits using eco-evolutionary modeling. The framework should also help predict distribution limits of invasive species and under climate change. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT “Assessing behavioral associations in a hybrid zone through social network analysis: Complex assortative behaviors structure associations in a hybrid quail population” https://amnat.org/an/newpapers/JuneZonana.html The DOI will be https://dx.doi.org/10.1086/703158 RFID data and social network analyses link phenotype and fine-scale social structure in a hybrid quail population Animals must identify, attract, and compete for mates before reproducing. These mating behaviors strongly influence whether closely related species will hybridize in areas where they co-occur. Yet, our understanding of how behavior affects hybridization between species is hindered by the fact that mating occurs within a complex web of social interactions that are challenging to characterize. The social structure in which animals live determines who they will encounter as potential mates and competitors, and therefore shapes the opportunity for hybridization. In this study, Zonana et al. combine high-resolution behavioral data (captured with RFID tags) and network analyses to test how sex, mass, and plumage traits correlate with social structure across an entire breeding, hybrid population of quail. Their study takes place within the hybrid zone between the California and Gambel’s quail, where the species’ ranges overlap in the deserts and mountains of Southern California. The authors find that social associations between these gregarious birds are strongest and most prevalent between individuals of the opposite sex, and these male-female associations disproportionately occur between individuals with similar mass and plumage traits that are shared by both males and females. Yet, the quail's social networks are random with respect to plumage traits that differ between the two species. The authors discuss how these complex patterns of behavior may facilitate hybridization between these species. The study demonstrates how network analyses can be used to test the influence of multiple traits on social associations (within and between both sexes and species) in natural, breeding populations. The authors’ framework provides a promising approach towards better understanding how animal behavior drives genetic exchange between populations and species. Abstract Behavior can strongly influence rates and patterns of hybridization between animal populations and species. Yet few studies have examined reproductive behaviors in natural hybrid zones within the fine-scale social structure in which they take place. We use radio-frequency identification (RFID) tags with social network analyses to test whether phenotypic similarity in plumage and mass correlate with social behavior throughout a breeding season in a California and Gambel’s quail hybrid zone. We use a novel approach to partition phenotypic variation in a way that does not confound differences between sexes and species, and illustrate the complex ways that phenotype and behavior structure the social environment, mating opportunities, and male-male associations. Associations within the admixed population were random with respect to species-specific plumage, but showed strong patterns of assortment based upon sexually dimorphic plumage, monomorphic plumage, and mass. Weak behavioral reproductive isolation in this admixed population may be the result of complex patterns of phenotypic assortment based upon multiple traits, rather than a lack of phenotypic discrimination. More generally, our results inform the utility of social network analyses for analyzing behavioral factors affecting genetic exchange between populations and species. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703158 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703158">Read the Article</a></i> </p> --> <p><b>RFID data and social network analyses link phenotype and fine-scale social structure in a hybrid quail population </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>nimals must identify, attract, and compete for mates before reproducing. These mating behaviors strongly influence whether closely related species will hybridize in areas where they co-occur. Yet, our understanding of how behavior affects hybridization between species is hindered by the fact that mating occurs within a complex web of social interactions that are challenging to characterize. The social structure in which animals live determines who they will encounter as potential mates and competitors, and therefore shapes the opportunity for hybridization. In this study, Zonana et al. combine high-resolution behavioral data (captured with RFID tags) and network analyses to test how sex, mass, and plumage traits correlate with social structure across an entire breeding, hybrid population of quail. Their study takes place within the hybrid zone between the California and Gambel’s quail, where the species’ ranges overlap in the deserts and mountains of Southern California. The authors find that social associations between these gregarious birds are strongest and most prevalent between individuals of the opposite sex, and these male-female associations disproportionately occur between individuals with similar mass and plumage traits that are shared by both males and females. Yet, the quail's social networks are random with respect to plumage traits that differ between the two species. The authors discuss how these complex patterns of behavior may facilitate hybridization between these species. The study demonstrates how network analyses can be used to test the influence of multiple traits on social associations (within and between both sexes and species) in natural, breeding populations. The authors’ framework provides a promising approach towards better understanding how animal behavior drives genetic exchange between populations and species. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">B</span>ehavior can strongly influence rates and patterns of hybridization between animal populations and species. Yet few studies have examined reproductive behaviors in natural hybrid zones within the fine-scale social structure in which they take place. We use radio-frequency identification (RFID) tags with social network analyses to test whether phenotypic similarity in plumage and mass correlate with social behavior throughout a breeding season in a California and Gambel’s quail hybrid zone. We use a novel approach to partition phenotypic variation in a way that does not confound differences between sexes and species, and illustrate the complex ways that phenotype and behavior structure the social environment, mating opportunities, and male-male associations. Associations within the admixed population were random with respect to species-specific plumage, but showed strong patterns of assortment based upon sexually dimorphic plumage, monomorphic plumage, and mass. Weak behavioral reproductive isolation in this admixed population may be the result of complex patterns of phenotypic assortment based upon multiple traits, rather than a lack of phenotypic discrimination. More generally, our results inform the utility of social network analyses for analyzing behavioral factors affecting genetic exchange between populations and species. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT “Species’ range dynamics affect the evolution of spatial variation in plasticity under environmental change” https://amnat.org/an/newpapers/JuneSchmid-A.html The DOI will be https://dx.doi.org/10.1086/703171 An alternative to the climate variability hypothesis: Geographic clines in plasticity evolve during range dynamics Abstract While clines in environmental tolerance and phenotypic plasticity along a single species’ range have been reported repeatedly and are of special interest in the context of adaptation to environmental changes, we know little about their evolution. Recent empirical findings in ectotherms suggest that processes underlying dynamic species’ ranges can give rise to spatial differences in environmental tolerance and phenotypic plasticity within species. We used individual-based simulations to investigate how plasticity and tolerance evolve in the course of three scenarios of species’ range shifts and range expansions on environmental gradients. We found that regions of a species’ range which experienced a longer history or larger extent of environmental change generally exhibited increased plasticity or tolerance. Such regions may be at the trailing edge when a species is tracking its ecological niche in space (e.g., in a climate change scenario) or at the front edge when a species expands into a new habitat (e.g., in an expansion/invasion scenario). Elevated tolerance and plasticity in the distribution center was detected when asymmetric environmental change (e.g., polar amplification) led to a range expansion. However, tolerance and plasticity clines were transient and slowly flattened out after range dynamics because of genetic assimilation. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703171 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703171">Read the Article</a></i> </p> --> <p><b>An alternative to the climate variability hypothesis: Geographic clines in plasticity evolve during range dynamics </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">W</span>hile clines in environmental tolerance and phenotypic plasticity along a single species’ range have been reported repeatedly and are of special interest in the context of adaptation to environmental changes, we know little about their evolution. Recent empirical findings in ectotherms suggest that processes underlying dynamic species’ ranges can give rise to spatial differences in environmental tolerance and phenotypic plasticity within species. We used individual-based simulations to investigate how plasticity and tolerance evolve in the course of three scenarios of species’ range shifts and range expansions on environmental gradients. We found that regions of a species’ range which experienced a longer history or larger extent of environmental change generally exhibited increased plasticity or tolerance. Such regions may be at the trailing edge when a species is tracking its ecological niche in space (e.g., in a climate change scenario) or at the front edge when a species expands into a new habitat (e.g., in an expansion/invasion scenario). Elevated tolerance and plasticity in the distribution center was detected when asymmetric environmental change (e.g., polar amplification) led to a range expansion. However, tolerance and plasticity clines were transient and slowly flattened out after range dynamics because of genetic assimilation.</p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT “The evolution of indiscriminate altruism in a cooperatively breeding mammal” https://amnat.org/an/newpapers/JuneDuncan.html The DOI will be https://dx.doi.org/10.1086/703113 Why do animals cooperate? One of the most powerful explanations for the evolution of cooperation is kin selection theory, which suggests that altruism may evolve when cooperative behaviors are directed towards genetic relatives. Meerkats, a species of cooperatively breeding mongoose, exhibit a wide range of cooperative behaviors; they babysit and feed the newly born pups of other individuals, look out for predators, and work to maintain hiding holes and sleeping burrows for the group. In this paper, researchers from the University of Cambridge analyzed data from a long-term study of meerkats in the Southern Kalahari Desert, South Africa. They find that although meerkat helpers cooperate extensively, individual helpers do not appear to provide more assistance to more closely related kin – they are indiscriminate altruists. Why is this the case? The researchers hypothesize that in groups of high genetic relatedness (as seen in meerkats), natural selection could favor indiscriminate altruism over kin-discriminate altruism if individuals frequently make mistakes in estimating their relatedness to group mates. However, in groups of lower genetic relatedness (such as humans), indiscriminate altruism is unlikely to evolve, even when kin-recognition is prone to substantial error. This provides an explanation for both the evolution of indiscriminate altruism in meerkats and the association between group relatedness and kin-discriminate altruism reported across vertebrates more generally. Abstract Kin selection theory suggests that altruistic behaviors can increase the fitness of altruists when recipients are genetic relatives. Although selection can favor the ability of organisms to preferentially cooperate with close kin, indiscriminately helping all group mates may yield comparable fitness returns if relatedness within groups is very high. Here, we show that meerkats (Suricata suricatta) are largely indiscriminate altruists who do not alter the amount of help provided to pups or group mates in response to their relatedness to them. We present a model showing that indiscriminate altruism may yield greater fitness payoffs than kin discrimination where most group members are close relatives and errors occur in the estimation of relatedness. The presence of errors in the estimation of relatedness provides a feasible explanation for associations between kin discriminative helping and group relatedness in eusocial and cooperatively breeding animals. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703113 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703113">Read the Article</a></i> </p> --><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">W</span>hy do animals cooperate? One of the most powerful explanations for the evolution of cooperation is kin selection theory, which suggests that altruism may evolve when cooperative behaviors are directed towards genetic relatives. Meerkats, a species of cooperatively breeding mongoose, exhibit a wide range of cooperative behaviors; they babysit and feed the newly born pups of other individuals, look out for predators, and work to maintain hiding holes and sleeping burrows for the group. In this paper, researchers from the University of Cambridge analyzed data from a long-term study of meerkats in the Southern Kalahari Desert, South Africa. They find that although meerkat helpers cooperate extensively, individual helpers do not appear to provide more assistance to more closely related kin – they are indiscriminate altruists. Why is this the case? The researchers hypothesize that in groups of high genetic relatedness (as seen in meerkats), natural selection could favor indiscriminate altruism over kin-discriminate altruism if individuals frequently make mistakes in estimating their relatedness to group mates. However, in groups of lower genetic relatedness (such as humans), indiscriminate altruism is unlikely to evolve, even when kin-recognition is prone to substantial error. This provides an explanation for both the evolution of indiscriminate altruism in meerkats and the association between group relatedness and kin-discriminate altruism reported across vertebrates more generally. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">K</span>in selection theory suggests that altruistic behaviors can increase the fitness of altruists when recipients are genetic relatives. Although selection can favor the ability of organisms to preferentially cooperate with close kin, indiscriminately helping all group mates may yield comparable fitness returns if relatedness within groups is very high. Here, we show that meerkats (<i>Suricata suricatta</i>) are largely indiscriminate altruists who do not alter the amount of help provided to pups or group mates in response to their relatedness to them. We present a model showing that indiscriminate altruism may yield greater fitness payoffs than kin discrimination where most group members are close relatives and errors occur in the estimation of relatedness. The presence of errors in the estimation of relatedness provides a feasible explanation for associations between kin discriminative helping and group relatedness in eusocial and cooperatively breeding animals. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT “Macroevolutionary patterning in glucocorticoids suggests different selective pressures shape baseline and stress-induced levels” https://amnat.org/an/newpapers/JuneVitousek.html The DOI will be https://dx.doi.org/10.1086/703112 New analysis suggests consistency in how some selective pressures shape glucocorticoid hormones across tetrapods Abstract Glucocorticoid (GC) hormones are important phenotypic mediators across vertebrates, but their circulating concentrations can vary markedly. Here we investigate macroevolutionary patterning in GC levels across tetrapods by testing seven specific hypotheses about GC variation, and evaluating whether the supported hypotheses reveal consistent patterns in GC evolution. If selection generally favors the “supportive” role of GCs in responding effectively to challenges, then baseline and/or stress-induced GCs may be higher in challenging contexts. Alternatively, if selection generally favors “protection” from GC-induced costs, GCs may be lower in environments where challenges are more common or severe. The predictors of baseline GCs were all consistent with supportive effects: levels were higher in smaller organisms, and in those inhabiting more energetically demanding environments. During breeding, baseline GCs were also higher in populations and species with fewer lifetime opportunities to reproduce. The predictors of stress-induced GCs were instead more consistent with the protection hypothesis: during breeding, levels were lower in organisms with fewer lifetime reproductive opportunities. Overall, these patterns indicate a surprising degree of consistency in how some selective pressures shape GCs across broad taxonomic scales; at the same time, in challenging environments selection appears to operate on baseline and stress-induced GCs in distinct ways. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703112 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703112">Read the Article</a></i> </p> --> <p><b>New analysis suggests consistency in how some selective pressures shape glucocorticoid hormones across tetrapods </b></p><!-- <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span> </p> <hr /> --> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">G</span>lucocorticoid (GC) hormones are important phenotypic mediators across vertebrates, but their circulating concentrations can vary markedly. Here we investigate macroevolutionary patterning in GC levels across tetrapods by testing seven specific hypotheses about GC variation, and evaluating whether the supported hypotheses reveal consistent patterns in GC evolution. If selection generally favors the “supportive” role of GCs in responding effectively to challenges, then baseline and/or stress-induced GCs may be higher in challenging contexts. Alternatively, if selection generally favors “protection” from GC-induced costs, GCs may be lower in environments where challenges are more common or severe. The predictors of baseline GCs were all consistent with supportive effects: levels were higher in smaller organisms, and in those inhabiting more energetically demanding environments. During breeding, baseline GCs were also higher in populations and species with fewer lifetime opportunities to reproduce. The predictors of stress-induced GCs were instead more consistent with the protection hypothesis: during breeding, levels were lower in organisms with fewer lifetime reproductive opportunities. Overall, these patterns indicate a surprising degree of consistency in how some selective pressures shape GCs across broad taxonomic scales; at the same time, in challenging environments selection appears to operate on baseline and stress-induced GCs in distinct ways. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT “How does the evolution of universal ecological traits affect population size? Lessons from simple models” https://amnat.org/an/newpapers/JuneAbrams.html The DOI will be https://dx.doi.org/10.1086/703155 Theory shows that adaptive evolution should frequently decrease population size, even in simple systems Does evolutionary change via natural selection usually increase population size? Do maladaptive processes (e.g., deleterious mutations) generally decrease population size? Many biologists would answer both questions in the affirmative, while acknowledging some exceptions. Nevertheless, many simple and widely used ecological models predict that adaptation via natural selection should often reduce population size (and that maladaptive processes should have the opposite effect). Both processes can be termed ‘adaptive decline’. Adaptive change in any of the three basic ecological properties that characterize all biological species—rate of taking up resources, rate of converting them to offspring, and probability of survival—is expected to lead to an ‘overly high’ rate of resource uptake; i.e., a rate greater than that which maximizes its population size. Overly high uptake rates may cause lower population size due to three mechanisms: (1) higher death rates or lower conversion efficiencies due to tradeoffs with uptake ability; (2) decreased productivity of the resource due to its lower population size; and/or (3) decreased productivity due to increased defense by the resource. Models predict that species experiencing a new environment are almost equally likely to increase or decrease their equilibrium population size as a result of their subsequent adaptive evolution. Even new genotypes that only affect all of the basic ecological properties in a fitness-increasing manner can decrease population size via decreased resource productivity or increased resource defense. Unfortunately, changes in population size during a period of adaptive genetic change are seldom measured, and we know little about the occurrence of overexploitation. If adaptive decline is in fact rare, it implies that our most widely used models of predator-prey or consumer-resource interactions are missing some element that is key to understanding how population sizes change as a consequence of evolution. The author, Peter Abrams, became interested in this topic while working on its ecological analogue, i.e., when environmental change causes an immediate harm to individuals of a species, but nevertheless increases its ultimate population size. Abstract This article argues that adaptive evolutionary change in a consumer species should frequently decrease (and maladaptive change should increase) population size, producing ‘adaptive decline’. This conclusion is based on analysis of multiple consumer-resource models that examine evolutionary change in consumer traits affecting the universal ecological parameters of attack rate, conversion efficiency, and mortality. Two scenarios are investigated. Under one, evolutionary equilibrium is initially maintained by opposing effects on the attack rate and other growth-rate parameters; the environment or trait is perturbed and the trait then evolves to a new (or back to a previous) equilibrium. Here evolution exhibits adaptive decline in up to one-half of all cases. The other scenario assumes a genetic perturbation having purely fitness-increasing effects. Here, adaptive decline in the consumer requires that the resource be self-reproducing and overexploited, and requires a sufficient increase in the attack rate. However, if the resource exhibits adaptive defense via behavior or evolution, adaptive decline may characterize consumer traits affecting all parameters. Favorable environmental change producing parameter shifts similar to those produced by adaptive evolution has similar counter-intuitive effects on consumer population size. Many different food web models have already been shown to exhibit such counterintuitive changes in some species. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703155 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703155">Read the Article</a></i> </p> --> <p><b>Theory shows that adaptive evolution should frequently decrease population size, even in simple systems </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">D</span>oes evolutionary change via natural selection usually increase population size? Do maladaptive processes (e.g., deleterious mutations) generally decrease population size? Many biologists would answer both questions in the affirmative, while acknowledging some exceptions. Nevertheless, many simple and widely used ecological models predict that adaptation via natural selection should often reduce population size (and that maladaptive processes should have the opposite effect). Both processes can be termed ‘adaptive decline’. Adaptive change in any of the three basic ecological properties that characterize all biological species—rate of taking up resources, rate of converting them to offspring, and probability of survival—is expected to lead to an ‘overly high’ rate of resource uptake; i.e., a rate greater than that which maximizes its population size. Overly high uptake rates may cause lower population size due to three mechanisms: (1) higher death rates or lower conversion efficiencies due to tradeoffs with uptake ability; (2) decreased productivity of the resource due to its lower population size; and/or (3) decreased productivity due to increased defense by the resource. Models predict that species experiencing a new environment are almost equally likely to increase or decrease their equilibrium population size as a result of their subsequent adaptive evolution. Even new genotypes that only affect all of the basic ecological properties in a fitness-increasing manner can decrease population size via decreased resource productivity or increased resource defense. Unfortunately, changes in population size during a period of adaptive genetic change are seldom measured, and we know little about the occurrence of overexploitation. If adaptive decline is in fact rare, it implies that our most widely used models of predator-prey or consumer-resource interactions are missing some element that is key to understanding how population sizes change as a consequence of evolution. </p> <p>The author, Peter Abrams, became interested in this topic while working on its ecological analogue, i.e., when environmental change causes an immediate harm to individuals of a species, but nevertheless increases its ultimate population size. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>his article argues that adaptive evolutionary change in a consumer species should frequently decrease (and maladaptive change should increase) population size, producing ‘adaptive decline’. This conclusion is based on analysis of multiple consumer-resource models that examine evolutionary change in consumer traits affecting the universal ecological parameters of attack rate, conversion efficiency, and mortality. Two scenarios are investigated. Under one, evolutionary equilibrium is initially maintained by opposing effects on the attack rate and other growth-rate parameters; the environment or trait is perturbed and the trait then evolves to a new (or back to a previous) equilibrium. Here evolution exhibits adaptive decline in up to one-half of all cases. The other scenario assumes a genetic perturbation having purely fitness-increasing effects. Here, adaptive decline in the consumer requires that the resource be self-reproducing and overexploited, and requires a sufficient increase in the attack rate. However, if the resource exhibits adaptive defense via behavior or evolution, adaptive decline may characterize consumer traits affecting all parameters. Favorable environmental change producing parameter shifts similar to those produced by adaptive evolution has similar counter-intuitive effects on consumer population size. Many different food web models have already been shown to exhibit such counterintuitive changes in some species. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 28 Feb 2019 06:00:00 GMT Links to the ASN Policy Statements https://amnat.org/announcements/Policy.html Letter to Secretary Azar on the Scientific Understanding of Sex and Gender Joint Societies Letter to the EPA on Using All Available Data Letter to the NSF about the Doctoral Dissertation Improvement Grant Program ASN Attends Congressional Visits Day 2017 Letter to the U.S. Congress on the Endangered Species Act Letter to the U.S. Congress on Plant Conservation Legislation Joint Societies&#39; Letter to the Trump Administration on Travel Restrictions Letter to the US Congress on Proposed Tax Cuts and Jobs Act Contact asnpresident@gmail.com The committee often works in coordination with the Public Policy Committee of the Society for the Study of Evolution: http://www.evolutionsociety.org/content/policy.html <ul> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTRgender.html">Letter to Secretary Azar on the Scientific Understanding of Sex and Gender</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTREPA.html">Joint Societies Letter to the EPA on Using All Available Data</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTRDDIG.html">Letter to the NSF about the Doctoral Dissertation Improvement Grant Program</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/ReportAIBS.html">ASN Attends Congressional Visits Day 2017</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTRspecies.html">Letter to the U.S. Congress on the Endangered Species Act</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTRplant.html">Letter to the U.S. Congress on Plant Conservation Legislation</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://www.amnat.org/announcements/LTRvisa.html">Joint Societies&#39; Letter to the Trump Administration on Travel Restrictions</a></h2> </li> <li> <h2 style="margin: 0px; padding: 0px; font-size: 24px; color: rgb(0, 88, 37); font-family: Georgia, Georgia, &quot;Times New Roman&quot;, Times, serif; line-height: 31.2px; text-decoration: none; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(235, 253, 255);"><a href="https://amnat.org/announcements/LTRTuitionTax.html">Letter to the US Congress on Proposed Tax Cuts and Jobs Act</a></h2> </li> </ul><p><strong>Contact <a href="mailto:asnpresident@gmail.com">asnpresident@gmail.com</a></strong></p> <p>The committee often works in coordination with the Public Policy Committee of the Society for the Study of Evolution: <a href="http://www.evolutionsociety.org/content/policy.html">http://www.evolutionsociety.org/content/policy.html</a></p> Mon, 18 Feb 2019 06:00:00 GMT 2019 Jasper Loftus-Hills Young Investigator Awards https://amnat.org/announcements/ANNwinYIA.html The American Society of Naturalist’s Young Investigator Award is in honor of Jasper Loftus-Hills, a young scientist who died tragically 3 years after receiving his PhD. This award goes to applicants who completed their PhD three years preceding the application deadline or are in their last year of a PhD program. Jeremy Fox, chair of the nominating committee, has written a blog about the experience. As he says, "The strength and diversity of the winners reflect the strength and diversity of the applicant pool, both in terms of their research areas and demographics." We are pleased to announce that this year’s recipients of the ASN Young Investiagor Awards are: &bull;&nbsp;&nbsp; &nbsp;Eleanor Caves: https://eleanorcaves.weebly.com/ &bull;&nbsp;&nbsp; &nbsp;Jean Philippe Gibert: https://jeanpgibert.weebly.com/ &bull;&nbsp;&nbsp; &nbsp;Ambika Kamath: https://ambikamath.wordpress.com/ &bull;&nbsp;&nbsp;&nbsp; Stilianos Louca:&nbsp;https://biology.uoregon.edu/profile/slouca/ We very much looking forward to their participation in the ASN YIA symposium at the annual meeting in Providence, Rhode Island, this summer. &nbsp; <p>The American Society of Naturalist&rsquo;s Young Investigator Award is in honor of Jasper Loftus-Hills, a young scientist who died tragically 3 years after receiving his PhD. This award goes to applicants who completed their PhD three years preceding the application deadline or are in their last year of a PhD program.</p> <p>Jeremy Fox, chair of the nominating committee, has <a href="https://dynamicecology.wordpress.com/2018/02/19/the-winners-of-the-asn-jasper-loftus-hills-young-investigator-awards-have-been-announced/">written a blog</a> about the experience. As he says, &quot;The strength and diversity of the winners reflect the strength and diversity of the applicant pool, both in terms of their research areas and demographics.&quot;</p> <p>We are pleased to announce that this year&rsquo;s recipients of the ASN Young Investiagor Awards are:</p> <p>&bull;&nbsp;&nbsp; &nbsp;Eleanor Caves: <a href="https://eleanorcaves.weebly.com/">https://eleanorcaves.weebly.com/</a><br /> &bull;&nbsp;&nbsp; &nbsp;Jean Philippe Gibert: <a href="https://jeanpgibert.weebly.com/">https://jeanpgibert.weebly.com/</a><br /> &bull;&nbsp;&nbsp; &nbsp;Ambika Kamath: <a href="https://ambikamath.wordpress.com/">https://ambikamath.wordpress.com/</a><br /> &bull;&nbsp;&nbsp;&nbsp; Stilianos Louca:&nbsp;<a href="https://biology.uoregon.edu/profile/slouca/">https://biology.uoregon.edu/profile/slouca/</a></p> <p>We very much looking forward to their participation in the ASN YIA symposium at the annual meeting in Providence, Rhode Island, this summer.</p> <p>&nbsp;</p> Mon, 18 Feb 2019 06:00:00 GMT “Revisiting a key innovation in evolutionary biology: Felsenstein’s ‘Phylogenies and the comparative method’” https://amnat.org/an/newpapers/JuneHuey.html The DOI will be https://dx.doi.org/10.1086/703055 We review how Felsenstein’s 1985 paper on phylogenies and the comparative method revolutionized evolutionary biology Abstract The comparative method has long been a fundamental exploratory tool in evolutionary biology, but this venerable approach was revolutionized in 1985, when Felsenstein published “Phylogenies and the Comparative Method” in The&nbsp;American Naturalist. This paper forced comparative biologists to start thinking phylogenetically when conducting statistical analyses of correlated trait evolution, rather than simply applying conventional statistical methods that ignore evolutionary relationships. It did so by introducing a novel analytical method (phylogenetically “independent contrasts”) that required a phylogenetic topology with branch lengths and that assumed a Brownian motion model of trait evolution. Independent contrasts enabled comparative biologists to avoid the statistical dilemma of non-independence of species values, arising from shared ancestry, but came at the cost of needing a detailed phylogeny and of accepting a specific model of character change. Nevertheless, this paper not only revitalized comparative biology, but even encouraged studies aimed at estimating phylogenies. Felsenstein’s characteristically lucid and concise statement of the problem (illustrated with powerful graphics), coupled with an oncoming flood of new molecular data and techniques for estimating phylogenies, led Felsenstein&nbsp;’85 to become the second most cited paper in the history of this journal. Here we present a personal review of comparative biology before, during, and after Joe’s paper. For historical context, we append a Perspective written by Joe himself (Appendix&nbsp;A, which describes how his paper evolved), unedited transcripts of reviews of his submitted manuscript (Appendix&nbsp;B), and a guide to some non-trivial calculations (Appendix&nbsp;C). These additional materials help emphasize that the process of science does not always occur gradually or predictably. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/703055 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/703055">Read the Article</a></i> </p> --> <p><b>We review how Felsenstein’s 1985 paper on phylogenies and the comparative method revolutionized evolutionary biology </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he comparative method has long been a fundamental exploratory tool in evolutionary biology, but this venerable approach was revolutionized in 1985, when Felsenstein published “Phylogenies and the Comparative Method” in <i>The&nbsp;American Naturalist</i>. This paper forced comparative biologists to start thinking phylogenetically when conducting statistical analyses of correlated trait evolution, rather than simply applying conventional statistical methods that ignore evolutionary relationships. It did so by introducing a novel analytical method (phylogenetically “independent contrasts”) that required a phylogenetic topology with branch lengths and that assumed a Brownian motion model of trait evolution. Independent contrasts enabled comparative biologists to avoid the statistical dilemma of non-independence of species values, arising from shared ancestry, but came at the cost of needing a detailed phylogeny and of accepting a specific model of character change. Nevertheless, this paper not only revitalized comparative biology, but even encouraged studies aimed at estimating phylogenies. Felsenstein’s characteristically lucid and concise statement of the problem (illustrated with powerful graphics), coupled with an oncoming flood of new molecular data and techniques for estimating phylogenies, led Felsenstein&nbsp;’85 to become the second most cited paper in the history of this journal. Here we present a personal review of comparative biology before, during, and after Joe’s paper. For historical context, we append a Perspective written by Joe himself (Appendix&nbsp;A, which describes how his paper evolved), unedited transcripts of reviews of his submitted manuscript (Appendix&nbsp;B), and a guide to some non-trivial calculations (Appendix&nbsp;C). These additional materials help emphasize that the process of science does not always occur gradually or predictably. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 14 Feb 2019 06:00:00 GMT “Trait-based modeling of multi-host pathogen transmission: Plant-pollinator networks” https://amnat.org/an/newpapers/JuneTruitt.html The DOI will be https://dx.doi.org/10.1086/701898 A new modeling approach for disease spread in plant-pollinator networks suggests new ideas for controlling bee diseases A&nbsp;bee visiting a flower to gather nectar might pick up an unwelcome extra: a virus (or another infectious disease organism) deposited there by a previous visitor. Because infectious disease is one of the factors implicated in recent declines of bees and other natural pollinators, there is increasing interest in finding practical ways to reduce the spread of these diseases. Mathematical models have often been helpful for identifying “disease hotspots” and designing effective disease control strategies in humans and wildlife. Disease spread in species-rich plant-pollinator interaction networks poses the challenge that a model describing each of the many distinct interactions (among multiple pollinator and flower species) would require an enormous number of parameters and an enormous amount of data to estimate those parameters. In a new paper in The American Naturalist, Truitt et al. propose an alternative trait-based approach to modeling disease spread in complex plant-pollinator networks. As one example, many such networks are “nested”: non-choosy pollinators visit all flowers, and more choosy ones visit smaller and smaller subsets of those visited by the less choosy. Truitt et al. model a nested network in terms of two traits: pollinator “choosiness” and flower “attractiveness”, where choosiness determines how much a pollinator concentrates on the more attractive flowers. Given the pollinator and flower trait distributions, one parameter (maximum choosiness) specifies the relative risk of disease spread in different interactions. Mathematical and computational studies of this model (mostly by Lauren Truitt and co-author Andrew Vaughn), and another where bees preferentially visit flowers of a size matching their own, demonstrate that the key interactions are those involving flowers visited out of proportion to their abundance, and pollinators which preferentially visit those flowers. This finding suggests strategies, based on feasible data gathering, to reduce disease spread by changing the abundances of different plant species. Such strategies could be implemented in wildflower plantings whose goal is to improve pollinator health. The paper is an extension of Truitt’s undergraduate honors thesis at Cornell (directed by co-authors McArt and Ellner), where she co-majored in biology and mathematics. Vaughn is currently a Cornell senior majoring in mathematics, and Truitt is interning at NIH. Abstract Epidemiological models for multi-host pathogen systems often classify individuals taxonomically and use species-specific parameter values, but in species-rich communities, that approach may require intractably many parameters. Trait-based epidemiological models offer a potential solution, but have not accounted for within-species trait variation or between-species trait overlap. Here, we propose and study trait-based models with host and vector communities represented as trait distributions without regard to species identity. To illustrate this approach, we develop SIS models for disease spread in plant-pollinator networks with continuous trait distributions. We model trait-dependent contact rates in two common scenarios: nested networks, and specialized plant-pollinator interactions based on trait matching. We find that disease spread in plant-pollinator networks is impacted the most by selective pollinators, universally attractive flowers, and co-specialized plant-pollinator pairs. When extreme pollinator traits are rare, pollinators with common traits are most important for disease spread, whereas when extreme flower traits are rare, flowers with uncommon traits impact disease spread the most. Greater nestedness and specialization both typically promote disease persistence. Given recent pollinator declines caused in part by pathogens, we discuss how trait-based models could inform conservation strategies for wild and managed pollinators. Furthermore, while we have applied our model to pollinators and pathogens, its framework is general and can be transferred to any kind of species interactions, in any community. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/701898 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/701898">Read the Article</a></i> </p> --> <p><b>A new modeling approach for disease spread in plant-pollinator networks suggests new ideas for controlling bee diseases </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>&nbsp;bee visiting a flower to gather nectar might pick up an unwelcome extra: a virus (or another infectious disease organism) deposited there by a previous visitor. Because infectious disease is one of the factors implicated in recent declines of bees and other natural pollinators, there is increasing interest in finding practical ways to reduce the spread of these diseases. Mathematical models have often been helpful for identifying “disease hotspots” and designing effective disease control strategies in humans and wildlife. Disease spread in species-rich plant-pollinator interaction networks poses the challenge that a model describing each of the many distinct interactions (among multiple pollinator and flower species) would require an enormous number of parameters and an enormous amount of data to estimate those parameters. </p> <p>In a new paper in <i>The American Naturalist</i>, Truitt et al. propose an alternative trait-based approach to modeling disease spread in complex plant-pollinator networks. As one example, many such networks are “nested”: non-choosy pollinators visit all flowers, and more choosy ones visit smaller and smaller subsets of those visited by the less choosy. Truitt et al. model a nested network in terms of two traits: pollinator “choosiness” and flower “attractiveness”, where choosiness determines how much a pollinator concentrates on the more attractive flowers. Given the pollinator and flower trait distributions, one parameter (maximum choosiness) specifies the relative risk of disease spread in different interactions. Mathematical and computational studies of this model (mostly by Lauren Truitt and co-author Andrew Vaughn), and another where bees preferentially visit flowers of a size matching their own, demonstrate that the key interactions are those involving flowers visited out of proportion to their abundance, and pollinators which preferentially visit those flowers. This finding suggests strategies, based on feasible data gathering, to reduce disease spread by changing the abundances of different plant species. Such strategies could be implemented in wildflower plantings whose goal is to improve pollinator health.</p> <p>The paper is an extension of Truitt’s undergraduate honors thesis at Cornell (directed by co-authors McArt and Ellner), where she co-majored in biology and mathematics. Vaughn is currently a Cornell senior majoring in mathematics, and Truitt is interning at NIH. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">E</span>pidemiological models for multi-host pathogen systems often classify individuals taxonomically and use species-specific parameter values, but in species-rich communities, that approach may require intractably many parameters. Trait-based epidemiological models offer a potential solution, but have not accounted for within-species trait variation or between-species trait overlap. Here, we propose and study trait-based models with host and vector communities represented as trait distributions without regard to species identity. To illustrate this approach, we develop SIS models for disease spread in plant-pollinator networks with continuous trait distributions. We model trait-dependent contact rates in two common scenarios: nested networks, and specialized plant-pollinator interactions based on trait matching. We find that disease spread in plant-pollinator networks is impacted the most by selective pollinators, universally attractive flowers, and co-specialized plant-pollinator pairs. When extreme pollinator traits are rare, pollinators with common traits are most important for disease spread, whereas when extreme flower traits are rare, flowers with uncommon traits impact disease spread the most. Greater nestedness and specialization both typically promote disease persistence. Given recent pollinator declines caused in part by pathogens, we discuss how trait-based models could inform conservation strategies for wild and managed pollinators. Furthermore, while we have applied our model to pollinators and pathogens, its framework is general and can be transferred to any kind of species interactions, in any community.</p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 14 Feb 2019 06:00:00 GMT “When do shifts in trait dynamics precede population declines?” https://amnat.org/an/newpapers/MayBaruah.html The DOI will be https://dx.doi.org/10.1086/702849 Shifts in fitness related traits could precede population decline, and is influenced by a host of eco-evo factors Predicting population declines in response to environmental change is an ongoing challenge in ecology. Recent studies suggest that predicting such rapid declines might be possible by monitoring statistical signals (called early warning signals, EWSs) embedded within abundance time series. Both theoretical and empirical studies have shown that before a population declines, EWSs, such as temporal variance and autocorrelation in abundance, increase over time. There are, however, potential pitfalls associated with such signals, including, but not limited to, the requirement of high-quality abundance time-series data. Alternatively, it is possible to strengthen these signals by incorporating information from the dynamics of physical traits such as body size. These trait-inclusive EWSs have been shown to improve our ability to predict population declines over abundance-based EWSs. However, under what environmental, ecological, and evolutionary circumstances it is useful to use traits as an indicator of population decline, is unknown. In a new study appearing in The&nbsp;American Naturalist, Gaurav Baruah, Christopher Clements, Frédéric Guillaume, and Arpat Ozgul develop a theoretical model to investigate the circumstances under which trait shifts can precede population declines, and thus can act as an early warning signal. They show, using model simulations and empirical data from an experimental microcosm, that under slow to medium environmental change scenarios, shifts in traits are more likely to precede population declines. They further demonstrate that reliable environmental cues, high net reproductive rate, high levels of plasticity and genetic variation lead to shifts in traits preceding population declines, even during fast changes in the environment. Their findings provide crucial information on when biodiversity monitoring programs can target trait dynamics as potential early warning signals of impending population declines. Abstract Predicting population responses to environmental change is an ongoing challenge in ecology. Studies investigating the links between fitness-related phenotypic traits and demography have shown that trait dynamic responses to environmental change can sometimes precede population dynamic responses, and thus, can be used as an early warning signal. However, it is still unknown under which ecological and evolutionary circumstances, shifts in fitness-related traits can precede population responses to environmental perturbation. Here, we take a trait-based demographic approach and investigate both trait and population dynamics in a density-regulated population in response to a gradual change in the environment. We explore the ecological and evolutionary constraints under which shifts in fitness-related trait precedes a decline in population size. We show both analytically and with experimental data that under medium-to-slow rate of environmental change, shifts in a trait value can precede population decline. We further show the positive influence of environmental predictability, net reproductive rate, plasticity, and genetic variation on shifts in trait dynamics preceding potential population declines. These results still hold under non-constant genetic variation and environmental stochasticity. Our study highlights ecological and evolutionary circumstances under which a fitness-related trait can be used as an early warning signal of an impending population decline. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/702849 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702849">Read the Article</a></i> </p> --> <p><b>Shifts in fitness related traits could precede population decline, and is influenced by a host of eco-evo factors </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>redicting population declines in response to environmental change is an ongoing challenge in ecology. Recent studies suggest that predicting such rapid declines might be possible by monitoring statistical signals (called early warning signals, EWSs) embedded within abundance time series. Both theoretical and empirical studies have shown that before a population declines, EWSs, such as temporal variance and autocorrelation in abundance, increase over time. There are, however, potential pitfalls associated with such signals, including, but not limited to, the requirement of high-quality abundance time-series data. Alternatively, it is possible to strengthen these signals by incorporating information from the dynamics of physical traits such as body size. These trait-inclusive EWSs have been shown to improve our ability to predict population declines over abundance-based EWSs. However, under what environmental, ecological, and evolutionary circumstances it is useful to use traits as an indicator of population decline, is unknown.</p> <p>In a new study appearing in <i>The&nbsp;American Naturalist</i>, Gaurav Baruah, Christopher Clements, Frédéric Guillaume, and Arpat Ozgul develop a theoretical model to investigate the circumstances under which trait shifts can precede population declines, and thus can act as an early warning signal. They show, using model simulations and empirical data from an experimental microcosm, that under slow to medium environmental change scenarios, shifts in traits are more likely to precede population declines. They further demonstrate that reliable environmental cues, high net reproductive rate, high levels of plasticity and genetic variation lead to shifts in traits preceding population declines, even during fast changes in the environment. Their findings provide crucial information on when biodiversity monitoring programs can target trait dynamics as potential early warning signals of impending population declines.</p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>redicting population responses to environmental change is an ongoing challenge in ecology. Studies investigating the links between fitness-related phenotypic traits and demography have shown that trait dynamic responses to environmental change can sometimes precede population dynamic responses, and thus, can be used as an early warning signal. However, it is still unknown under which ecological and evolutionary circumstances, shifts in fitness-related traits can precede population responses to environmental perturbation. Here, we take a trait-based demographic approach and investigate both trait and population dynamics in a density-regulated population in response to a gradual change in the environment. We explore the ecological and evolutionary constraints under which shifts in fitness-related trait precedes a decline in population size. We show both analytically and with experimental data that under medium-to-slow rate of environmental change, shifts in a trait value can precede population decline. We further show the positive influence of environmental predictability, net reproductive rate, plasticity, and genetic variation on shifts in trait dynamics preceding potential population declines. These results still hold under non-constant genetic variation and environmental stochasticity. Our study highlights ecological and evolutionary circumstances under which a fitness-related trait can be used as an early warning signal of an impending population decline. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 12 Feb 2019 06:00:00 GMT “Higher nest predation favors rapid fledging at the cost of plumage quality in nestling birds” https://amnat.org/an/newpapers/MayCallan.html The DOI will be https://dx.doi.org/10.1086/702856 Trade offs of rapid development are expressed in body feathers of birds Developing too quickly often forces organisms to compromise the quality of traits they grow. But which traits should express these compromises in quality the most? Some traits must be used for the entire life cycle (bones, organs, immune systems) while other traits can be repaired or replaced later in life (feathers, exoskeletons, fur). These differences in the duration that traits are used suggest that when rapid development forces organisms to compromise trait quality, traits used for short periods of time should suffer the greatest losses in quality compared to traits used for life. The authors explore this idea using body feathers that young birds grow while in the nest. For many species, these feathers are replaced shortly after leaving the nest, making them a short-lived trait. Species that grow and develop quickly show the greatest losses in nestling feather quality compared to species that develop more slowly. By contrast, adult survival probability across species shows no relationship with development speed. These contrasting findings between the quality of short-term traits like nestling feathers and long term traits like those important for adult survival, suggests that when organisms must develop rapidly, they compromise the quality of traits that can be repaired or replaced later in life. Abstract High predation risk can favor rapid offspring development at the expense of offspring quality. Impacts of rapid development on phenotypic quality should be most readily expressed in traits that minimize fitness costs. We hypothesize that ephemeral traits that are replaced or repaired after a short period of life might express trade-offs in quality as a result of rapid development more strongly than traits used throughout life. We explored this idea for plumage quality in nestling body feathers, an ephemeral trait. We found a strong trade-off whereby nestlings that spend less time in the nest produced lower quality plumage with less dense barbs relative to adults across 123 temperate and tropical species. For a subset of these species (n=67), we found that variation in the risk of nest predation explained additional variation in plumage quality beyond development time. Ultimately, the fitness costs of a poor quality ephemeral trait, like nestling body feathers, may be outweighed by the fitness benefits of shorter development times that reduce predation risk. At the same time, reduced resource allocation to traits with small fitness costs, like ephemeral traits, may ameliorate resource constraints from rapid development on traits with larger fitness impacts. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/702856 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702856">Read the Article</a></i> </p> --> <p><b>Trade offs of rapid development are expressed in body feathers of birds </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">D</span>eveloping too quickly often forces organisms to compromise the quality of traits they grow. But which traits should express these compromises in quality the most? Some traits must be used for the entire life cycle (bones, organs, immune systems) while other traits can be repaired or replaced later in life (feathers, exoskeletons, fur). These differences in the duration that traits are used suggest that when rapid development forces organisms to compromise trait quality, traits used for short periods of time should suffer the greatest losses in quality compared to traits used for life. </p> <p>The authors explore this idea using body feathers that young birds grow while in the nest. For many species, these feathers are replaced shortly after leaving the nest, making them a short-lived trait. Species that grow and develop quickly show the greatest losses in nestling feather quality compared to species that develop more slowly. By contrast, adult survival probability across species shows no relationship with development speed. These contrasting findings between the quality of short-term traits like nestling feathers and long term traits like those important for adult survival, suggests that when organisms must develop rapidly, they compromise the quality of traits that can be repaired or replaced later in life.</p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">H</span>igh predation risk can favor rapid offspring development at the expense of offspring quality. Impacts of rapid development on phenotypic quality should be most readily expressed in traits that minimize fitness costs. We hypothesize that ephemeral traits that are replaced or repaired after a short period of life might express trade-offs in quality as a result of rapid development more strongly than traits used throughout life. We explored this idea for plumage quality in nestling body feathers, an ephemeral trait. We found a strong trade-off whereby nestlings that spend less time in the nest produced lower quality plumage with less dense barbs relative to adults across 123 temperate and tropical species. For a subset of these species (<i>n</i>=67), we found that variation in the risk of nest predation explained additional variation in plumage quality beyond development time. Ultimately, the fitness costs of a poor quality ephemeral trait, like nestling body feathers, may be outweighed by the fitness benefits of shorter development times that reduce predation risk. At the same time, reduced resource allocation to traits with small fitness costs, like ephemeral traits, may ameliorate resource constraints from rapid development on traits with larger fitness impacts. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 12 Feb 2019 06:00:00 GMT “Predicting the thermal and allometric dependencies of disease transmission via the metabolic theory of ecology” https://amnat.org/an/newpapers/MayKirk.html Warming temperatures associated with climate change and host body size can both alter infectious disease spread, though often in complex ways. This is because both factors can affect different components of disease transmission, namely the contact rate between uninfected and infected individuals or parasites, and the subsequent likelihood that that contact results in a new infection. To understand how warming and size will affect disease spread in a host-parasite system, we need to first predict their effects on contact and infection rates, and then tie these predictions together using classic disease models of transmission. The metabolic theory of ecology (MTE) provides a general framework for predicting how temperature and host size affect contact and infection rates. Here, the authors conducted two experiments using a Daphnia–parasite system, and then fit MTE models to the data. They show that transmission is strongly affected by temperature, and that the different rates vary with temperature and body size in distinct manners. Moreover, they show that MTE functions can capture how contact rate and the probability of infection change across temperature and size. Together these two functions can accurately predict transmission rate continuously across a wide temperature range. This represents a valuable potential tool for helping predict how disease spread will change as environmental temperatures rise. Abstract The metabolic theory of ecology (MTE) provides a general framework of allometric and thermal dependence that may be useful for predicting how climate change will affect disease spread. Using Daphnia magna and a microsporidian gut parasite, we conducted two experiments across a wide thermal range and fitted transmission models that utilize MTE submodels for transmission parameters. We decomposed transmission into contact rate and probability of infection, and further decomposed probability of infection into a product of gut residence time (GRT) and per-parasite infection rate of gut cells. Contact rate generally increased with temperature and scaled positively with body size, whereas infection rate had a narrow hump-shaped thermal response and scaled negatively with body size. GRT increased with host size and was longest at extreme temperatures. GRT and infection rate inside the gut combined to create a 3.5× higher probability of infection for the smallest relative to the largest individuals. Small temperature changes caused large differences in transmission. We also fit several alternative transmission models to data at individual temperatures. The more complex models, parasite antagonism or synergism and host heterogeneity, did not substantially improve the fit to the data. Our results show that transmission rate is the product of several distinct thermal and allometric functions that can be predicted continuously across temperature and host size using MTE. More forthcoming papers &raquo; <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">W</span>arming temperatures associated with climate change and host body size can both alter infectious disease spread, though often in complex ways. This is because both factors can affect different components of disease transmission, namely the contact rate between uninfected and infected individuals or parasites, and the subsequent likelihood that that contact results in a new infection. To understand how warming and size will affect disease spread in a host-parasite system, we need to first predict their effects on contact and infection rates, and then tie these predictions together using classic disease models of transmission. The metabolic theory of ecology (MTE) provides a general framework for predicting how temperature and host size affect contact and infection rates. Here, the authors conducted two experiments using a <i>Daphnia</i>–parasite system, and then fit MTE models to the data. They show that transmission is strongly affected by temperature, and that the different rates vary with temperature and body size in distinct manners. Moreover, they show that MTE functions can capture how contact rate and the probability of infection change across temperature and size. Together these two functions can accurately predict transmission rate continuously across a wide temperature range. This represents a valuable potential tool for helping predict how disease spread will change as environmental temperatures rise.</p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he metabolic theory of ecology (MTE) provides a general framework of allometric and thermal dependence that may be useful for predicting how climate change will affect disease spread. Using <i>Daphnia magna</i> and a microsporidian gut parasite, we conducted two experiments across a wide thermal range and fitted transmission models that utilize MTE submodels for transmission parameters. We decomposed transmission into contact rate and probability of infection, and further decomposed probability of infection into a product of gut residence time (GRT) and per-parasite infection rate of gut cells. Contact rate generally increased with temperature and scaled positively with body size, whereas infection rate had a narrow hump-shaped thermal response and scaled negatively with body size. GRT increased with host size and was longest at extreme temperatures. GRT and infection rate inside the gut combined to create a 3.5× higher probability of infection for the smallest relative to the largest individuals. Small temperature changes caused large differences in transmission. We also fit several alternative transmission models to data at individual temperatures. The more complex models, parasite antagonism or synergism and host heterogeneity, did not substantially improve the fit to the data. Our results show that transmission rate is the product of several distinct thermal and allometric functions that can be predicted continuously across temperature and host size using MTE. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Wed, 06 Feb 2019 06:00:00 GMT “Sexually antagonistic variation and the evolution of dimorphic sexual systems” https://amnat.org/an/newpapers/MayOlito.html The DOI will be https://dx.doi.org/10.1086/702847 Sexually antagonistic variation promotes the evolution of separate sexes from hermaphroditism beyond classic predictions Understanding when and why separate sexes (dioecy) evolve from hermaphroditism is a fundamental question in evolutionary biology with a long and storied history. A key advance came in the late 1970’s, when Brian and Deborah Charlesworth developed a series of theoretical models, published here in The&nbsp;American Naturalist, describing the evolution of separate sexes from hermaphroditism via the invasion of nuclear unisexual sterility alleles, which abolish either the male or female sex-function in hermaphrodites (Charlesworth & Charlesworth 1978). This influential theory predicts that the evolution of separates sexes is most likely when female and male sex-functions genetically trade-off with one another, and rates of self-fertilization and inbreeding depression are high among hermaphrodites. Yet, while some studies of single species support this longstanding prediction, empirical evidence for an association between dioecy and selfing across taxa remains underwhelming. In their forthcoming article, Colin Olito and Tim Connallon reconsider this issue, extending the theory with a series of two-locus models involving both a ‘sterility locus’ (where a unisexual sterility mutation may occur), and another ‘sexually antagonistic locus’ (where alleles beneficial for one sex function are deleterious for the other). Their models show that genetic linkage of unisexual sterility alleles to a sexually antagonistic locus facilitates the initial step in the evolution of separate sexes and inverts the predicted relation between self-fertilization and dioecy relative to the predictions of the classical theory by essentially allowing unisexual sterility alleles to ‘hitchhike’ with SA alleles. Their findings suggest that dioecy may evolve from hermaphroditism under much broader conditions than previously thought and suggest a new role for sexually antagonistic genetic variation in the evolutionary origins of new sex-chromosome systems. References Charlesworth, B., and D. Charlesworth. 1978. A model for the evolution of dioecy and gynodioecy. The&nbsp;American Naturalist 112:975–997.Abstract Multicellular Eukaryotes use a broad spectrum of sexual reproduction strategies, ranging from simultaneous hermaphroditism to complete dioecy (separate sexes). The evolutionary pathway from hermaphroditism to dioecy involves the spread of “sterility alleles” that eliminate female or male reproductive functions, producing unisexual individuals. Classical theory predicts that evolutionary transitions to dioecy are feasible when female and male sex functions genetically trade-off with one another (allocation to sex functions is “sexually antagonistic”), and rates of self-fertilization and inbreeding depression are high within the ancestral hermaphrodite population. We show that genetic linkage between sterility alleles and loci under sexually antagonistic selection significantly alters these classical predictions. We identify three specific consequences of linkage for the evolution of dimorphic sexual systems. First, linkage broadens conditions for the invasion of unisexual sterility alleles, facilitating transitions to sexual systems that are intermediate between hermaphroditism and dioecy (andro- and gynodioecy). Second, linkage elevates the equilibrium frequencies of unisexual individuals within andro- and gynodioecious populations, which promotes subsequent transitions to full dioecy. Third, linkage dampens the role of inbreeding during transitions to andro- and gynodioecy, making these transitions feasible in outbred populations. We discuss implications of these results for the evolution of dimorphic reproductive systems and sex chromosomes. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/702847 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702847">Read the Article</a></i> </p> --> <p><b>Sexually antagonistic variation promotes the evolution of separate sexes from hermaphroditism beyond classic predictions </b></p><p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">U</span>nderstanding when and why separate sexes (dioecy) evolve from hermaphroditism is a fundamental question in evolutionary biology with a long and storied history. A key advance came in the late 1970&rsquo;s, when Brian and Deborah Charlesworth developed a series of theoretical models, published here in <i>The&nbsp;American Naturalist</i>, describing the evolution of separate sexes from hermaphroditism via the invasion of nuclear unisexual sterility alleles, which abolish either the male or female sex-function in hermaphrodites (Charlesworth &amp; Charlesworth 1978). This influential theory predicts that the evolution of separates sexes is most likely when female and male sex-functions genetically trade-off with one another, and rates of self-fertilization and inbreeding depression are high among hermaphrodites. Yet, while some studies of single species support this longstanding prediction, empirical evidence for an association between dioecy and selfing across taxa remains underwhelming. In their forthcoming article, Colin Olito and Tim Connallon reconsider this issue, extending the theory with a series of two-locus models involving both a &lsquo;sterility locus&rsquo; (where a unisexual sterility mutation may occur), and another &lsquo;sexually antagonistic locus&rsquo; (where alleles beneficial for one sex function are deleterious for the other). Their models show that genetic linkage of unisexual sterility alleles to a sexually antagonistic locus facilitates the initial step in the evolution of separate sexes and inverts the predicted relation between self-fertilization and dioecy relative to the predictions of the classical theory by essentially allowing unisexual sterility alleles to &lsquo;hitchhike&rsquo; with SA alleles. Their findings suggest that dioecy may evolve from hermaphroditism under much broader conditions than previously thought and suggest a new role for sexually antagonistic genetic variation in the evolutionary origins of new sex-chromosome systems.</p> <h4>References</h4> <p>Charlesworth, B., and D. Charlesworth. 1978. A model for the evolution of dioecy and gynodioecy. <i>The&nbsp;American Naturalist</i> 112:975&ndash;997.</p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">M</span>ulticellular Eukaryotes use a broad spectrum of sexual reproduction strategies, ranging from simultaneous hermaphroditism to complete dioecy (separate sexes). The evolutionary pathway from hermaphroditism to dioecy involves the spread of “sterility alleles” that eliminate female or male reproductive functions, producing unisexual individuals. Classical theory predicts that evolutionary transitions to dioecy are feasible when female and male sex functions genetically trade-off with one another (allocation to sex functions is “sexually antagonistic”), and rates of self-fertilization and inbreeding depression are high within the ancestral hermaphrodite population. We show that genetic linkage between sterility alleles and loci under sexually antagonistic selection significantly alters these classical predictions. We identify three specific consequences of linkage for the evolution of dimorphic sexual systems. First, linkage broadens conditions for the invasion of unisexual sterility alleles, facilitating transitions to sexual systems that are intermediate between hermaphroditism and dioecy (andro- and gynodioecy). Second, linkage elevates the equilibrium frequencies of unisexual individuals within andro- and gynodioecious populations, which promotes subsequent transitions to full dioecy. Third, linkage dampens the role of inbreeding during transitions to andro- and gynodioecy, making these transitions feasible in outbred populations. We discuss implications of these results for the evolution of dimorphic reproductive systems and sex chromosomes. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Wed, 06 Feb 2019 06:00:00 GMT “Upscaling microclimatic conditions into body temperature distributions of ectotherms” https://amnat.org/an/newpapers/MayRubalcaba.html The DOI will be https://dx.doi.org/10.1086/702717 An information-theoretical model to predict body temperature of ectotherms from microclimatic data A&nbsp;current challenge for quantitative ecologists is to forecast the organismal responses to climate change. This task requires developing models to predict, for example, how increasing ambient temperatures actually influence body temperature of individuals and their potential to adapt to novel climatic conditions. Many cold-blooded animals (such as invertebrates, frogs, or lizards) can control their body temperatures by exploiting the heterogeneity of their environment, choosing among sunny or shaded areas, basking sites or burrows. Using models to predict the response of cold-blooded animals to climate change is challenging because they require a vast amount of information to compute microhabitat preferences and physiological and behavioral features of species for which this information is often lacking. So far, there is no general model capable of dealing with uncertain information and still making accurate predictions on the actual body temperature of cold-blooded animals from climatic data. A team of researchers from Spain and Brazil has taken a step further in breaking this barrier by developing a model capable of predicting body temperature of lizards in the field. The model uses principles of information theory and statistical mechanics from physics to derive the most probable allocation scheme of individuals among the repertoire of microhabitats (e.g., sun, shade, burrows). Then, using a thermodynamic model, it computes the actual body temperature in a probabilistic way. Further, their model quantifies the importance of active control of body temperature for cold-blooded animals, for example, through avoiding exposure to sun radiation during the central hours of the day. In addition to providing a novel theoretical framework for understanding and simulating thermoregulation of cold-blooded animals, this study makes a first step towards reliable projections of organismal responses to future climates. Abstract Realistic projections of the biological impacts of climate change require predicting fitness responses to variations in environmental conditions. For ectotherms, this challenge requires methods to scale-up microclimatic information into actual body temperatures, Tb, while dealing with uncertainty regarding individual behaviors and physiological constraints. Here, we propose an information-theoretical model to derive microhabitat selection and Tb distributions of ectotherm populations from microclimatic data. The model infers the most probable allocation of individuals among the available microenvironments and the associated population-level Tb distribution. Using empirical Tb data of 41 species of desert lizards from three independently evolved systems – Western North America, Kalahari Desert, and Western Australia – we show that the model accurately predicts empirical Tb distributions across the three systems. Moreover, the framework naturally provides a way to quantify the importance of thermoregulation in a thermal environment and thereby a measurement for the constraint imposed by the climatic conditions. By predicting Tb distribution of ectotherm populations, even without exhaustive information on the underpinning mechanisms, our approach forms a solid theoretical basis for upscaling microclimatic and physiological information into a population-level fitness trait. This scaling process is a first step to reliably project the biological impacts of climate change to broad temporal and spatial scales. Escalando condiciones microclimáticas en distribuciones de temperatura corporal de ectotermos Para predecir de manera fiable los impactos bióticos del cambio climático, es necesario predecir cómo la eficacia biológica responde a variaciones en las condiciones ambientales. En ectotermos, este reto requiere de métodos que permitan escalar información microclimática a temperaturas corporales reales, Tb, y al mismo tiempo lidiar con la incertidumbre derivada de comportamientos individuales y limitantes fisiológicas. En este trabajo, proponemos un modelo basado en teoría de la información que permite calcular la preferencia de microhábitats y distribuciones de Tb de poblaciones de ectotermos a partir de datos microclimáticos. El modelo infiere la distribución espacial más probable de los individuos entre los microambientes disponibles y la distribución de Tb a nivel de población. Utilizando datos empíricos de Tb de 41 especies de lagartos de desierto provenientes de tres sistemas independientes –oeste de Norteamérica, Desierto del Kalahari y oeste de Australia– mostramos que el modelo logra predecir con precisión las distribuciones de Tb a través de los tres sistemas. Además de esto, el método permite cuantificar la importancia de la termorregulación en un ambiente térmico y con ello, aportar una medida de las restricciones térmicas impuestas por las condiciones climáticas. Al predecir la distribución de Tb de poblaciones de ectotermos, aún en ausencia de información exhaustiva de los mecanismos subyacentes, nuestro modelo aporta una base teórica sólida para estimar un rasgo relacionado con la eficacia biológica a nivel poblacional a partir de información microclimática y fisiológica. Este es un primer paso para predecir de manera fiable los impactos bióticos del cambio climático a escalas espaciales y temporales amplias. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/702717 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702717">Read the Article</a></i> </p> --> <p><b>An information-theoretical model to predict body temperature of ectotherms from microclimatic data </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>&nbsp;current challenge for quantitative ecologists is to forecast the organismal responses to climate change. This task requires developing models to predict, for example, how increasing ambient temperatures actually influence body temperature of individuals and their potential to adapt to novel climatic conditions. Many cold-blooded animals (such as invertebrates, frogs, or lizards) can control their body temperatures by exploiting the heterogeneity of their environment, choosing among sunny or shaded areas, basking sites or burrows. Using models to predict the response of cold-blooded animals to climate change is challenging because they require a vast amount of information to compute microhabitat preferences and physiological and behavioral features of species for which this information is often lacking. So far, there is no general model capable of dealing with uncertain information and still making accurate predictions on the actual body temperature of cold-blooded animals from climatic data. </p><p>A team of researchers from Spain and Brazil has taken a step further in breaking this barrier by developing a model capable of predicting body temperature of lizards in the field. The model uses principles of information theory and statistical mechanics from physics to derive the most probable allocation scheme of individuals among the repertoire of microhabitats (e.g., sun, shade, burrows). Then, using a thermodynamic model, it computes the actual body temperature in a probabilistic way. Further, their model quantifies the importance of active control of body temperature for cold-blooded animals, for example, through avoiding exposure to sun radiation during the central hours of the day. In addition to providing a novel theoretical framework for understanding and simulating thermoregulation of cold-blooded animals, this study makes a first step towards reliable projections of organismal responses to future climates. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">R</span>ealistic projections of the biological impacts of climate change require predicting fitness responses to variations in environmental conditions. For ectotherms, this challenge requires methods to scale-up microclimatic information into actual body temperatures, T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span>, while dealing with uncertainty regarding individual behaviors and physiological constraints. Here, we propose an information-theoretical model to derive microhabitat selection and T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> distributions of ectotherm populations from microclimatic data. The model infers the most probable allocation of individuals among the available microenvironments and the associated population-level T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> distribution. Using empirical T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> data of 41 species of desert lizards from three independently evolved systems – Western North America, Kalahari Desert, and Western Australia – we show that the model accurately predicts empirical T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> distributions across the three systems. Moreover, the framework naturally provides a way to quantify the importance of thermoregulation in a thermal environment and thereby a measurement for the constraint imposed by the climatic conditions. By predicting T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> distribution of ectotherm populations, even without exhaustive information on the underpinning mechanisms, our approach forms a solid theoretical basis for upscaling microclimatic and physiological information into a population-level fitness trait. This scaling process is a first step to reliably project the biological impacts of climate change to broad temporal and spatial scales. </p> <h4>Escalando condiciones microclimáticas en distribuciones de temperatura corporal de ectotermos</h4> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>ara predecir de manera fiable los impactos bióticos del cambio climático, es necesario predecir cómo la eficacia biológica responde a variaciones en las condiciones ambientales. En ectotermos, este reto requiere de métodos que permitan escalar información microclimática a temperaturas corporales reales, T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span>, y al mismo tiempo lidiar con la incertidumbre derivada de comportamientos individuales y limitantes fisiológicas. En este trabajo, proponemos un modelo basado en teoría de la información que permite calcular la preferencia de microhábitats y distribuciones de T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> de poblaciones de ectotermos a partir de datos microclimáticos. El modelo infiere la distribución espacial más probable de los individuos entre los microambientes disponibles y la distribución de T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> a nivel de población. Utilizando datos empíricos de T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> de 41 especies de lagartos de desierto provenientes de tres sistemas independientes –oeste de Norteamérica, Desierto del Kalahari y oeste de Australia– mostramos que el modelo logra predecir con precisión las distribuciones de T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> a través de los tres sistemas. Además de esto, el método permite cuantificar la importancia de la termorregulación en un ambiente térmico y con ello, aportar una medida de las restricciones térmicas impuestas por las condiciones climáticas. Al predecir la distribución de T<span style="font-size:70%; position:relative; bottom:-0.3em;">b</span> de poblaciones de ectotermos, aún en ausencia de información exhaustiva de los mecanismos subyacentes, nuestro modelo aporta una base teórica sólida para estimar un rasgo relacionado con la eficacia biológica a nivel poblacional a partir de información microclimática y fisiológica. Este es un primer paso para predecir de manera fiable los impactos bióticos del cambio climático a escalas espaciales y temporales amplias. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 04 Feb 2019 06:00:00 GMT Best Practices Checklist for Authors and Reviewers https://amnat.org/announcements/MS-Checklist.html A number of journals have introduced checklists in recent years, aimed at either reviewers or authors. The Editorial Board of The American Naturalist is adopting a checklist as well. It is for the use of authors and reviewers and not for submission to the journal. The intent is to remind authors of items that reviewers (and readers) expect in a paper. It may also serve to remind reviewers of things they should look for, but which often get overlooked. Because we receive both a mix of theory and data and synthesis and meta-analysis papers, there is no one-size-fits-all checklist. ____________ Rationale: A paper by Parker et al (2018. “Empowering peer reviewers with a checklist to improve transparency”, Nature Ecology and Evolution) advocated greater use of checklists in evaluating research publications. They argue that “Good checklists do not replace complex thought; they facilitate it. &hellip; by calling attention to essential elements that are often overlooked”. Here, we provide a set of checklists tailored to the diverse kinds of papers submitted to The American Naturalist. Authors and reviewers are not required to use this checklist, but it may help each identify common weaknesses that need to be fixed. Not all items in the following checklist pertain to all studies. It is the job of the authors and reviewers to judge what elements apply to any given study. The checklist is therefore not meant to be a straight-jacket, but rather a prompt to remind us what authors should aspire to do, and what reviewers should check for. The checklists below do not cover methods, syntheses, historical perspectives, and some other articles that are also welcome at this journal. Authors: The checklists are designed to remind you of key features that maximize transparency of your work and that reviewers look for in evaluating your work. We encourage you to examine relevant parts of this checklist before submissionof a new manuscript, or during revision, to ensure that you are meeting our expectations. Using this checklist may help you pre-emptively avoid common reviewer critiques. Authors should also visit the journal webpage for formatting details:&nbsp;&nbsp; https://www.journals.uchicago.edu/journals/an/instruct Reviewers: You may find the checklist to be a useful reminder of manuscript features to comment on, including somewhat mundane details that authors frequently forget to include (and reviewers frequently forget to check for). Contents: 1:&nbsp;&nbsp; General considerations 2:&nbsp;&nbsp; Articles with empirical data 3:&nbsp;&nbsp; Articles with meta-analysis 4:&nbsp;&nbsp; Articles with theory 5:&nbsp;&nbsp; Submission FormattingBest-practices-checklist-edited.pdf <p>A number of journals have introduced checklists in recent years, aimed at either reviewers or authors. The Editorial Board of <em>The American Naturalist</em> is adopting a checklist as well. <strong>It is for the use of authors and reviewers and not for submission to the journal. </strong></p> <p>The intent is to remind authors of items that reviewers (and readers) expect in a paper. It may also serve to remind reviewers of things they should look for, but which often get overlooked. Because we receive both a mix of theory and data and synthesis and meta-analysis papers, there is no one-size-fits-all checklist.</p> <p>____________</p> <p><strong>Rationale:</strong></p> <p>A paper by Parker et al (2018. &ldquo;Empowering peer reviewers with a checklist to improve transparency&rdquo;, <em>Nature Ecology and Evolution</em>) advocated greater use of checklists in evaluating research publications. They argue that &ldquo;Good checklists do not replace complex thought; they facilitate it. &hellip; by calling attention to essential elements that are often overlooked&rdquo;. Here, we provide a set of checklists tailored to the diverse kinds of papers submitted to <em>The American Naturalist.</em> Authors and reviewers are not required to use this checklist, but it may help each identify common weaknesses that need to be fixed. Not all items in the following checklist pertain to all studies. It is the job of the authors and reviewers to judge what elements apply to any given study. The checklist is therefore not meant to be a straight-jacket, but rather a prompt to remind us what authors should aspire to do, and what reviewers should check for. The checklists below do not cover methods, syntheses, historical perspectives, and some other articles that are also welcome at this journal.</p> <p><strong>Authors:</strong></p> <p>The checklists are designed to remind you of key features that maximize transparency of your work and that reviewers look for in evaluating your work. We encourage you to examine relevant parts of this checklist before submissionof a new manuscript, or during revision, to ensure that you are meeting our expectations. Using this checklist may help you pre-emptively avoid common reviewer critiques. Authors should also visit the journal webpage for formatting details:&nbsp;&nbsp; <a href="https://www.journals.uchicago.edu/journals/an/instruct">https://www.journals.uchicago.edu/journals/an/instruct</a></p> <p><strong>Reviewers</strong>:</p> <p>You may find the checklist to be a useful reminder of manuscript features to comment on, including somewhat mundane details that authors frequently forget to include (and reviewers frequently forget to check for).</p> <p>Contents:<br /> 1:&nbsp;&nbsp; General considerations<br /> 2:&nbsp;&nbsp; Articles with empirical data<br /> 3:&nbsp;&nbsp; Articles with meta-analysis<br /> 4:&nbsp;&nbsp; Articles with theory<br /> 5:&nbsp;&nbsp; Submission Formatting</p><p><a href="/dam/jcr:3cbc3ea2-1109-495e-9b7d-04cec4fc18d1/Best%20practices%20checklist%20edited.pdf">Best-practices-checklist-edited.pdf</a></p> Mon, 04 Feb 2019 06:00:00 GMT “Predicting habitat choice after rapid environmental change” https://amnat.org/an/newpapers/MayCrowley.html Read the ArticleChoosing where to settle is a critical decision various animals have to take, whether it is a bird choosing its nest site, or a fish larvae settling on a home coral. While we know that environmental changes are impacting many habitats and can have major fitness implications, it is harder to predict how these changes in the availability and quality of natural habitats will affect the settlement decisions of different species. A small number of species are actually thriving following environmental changes (e.g. pigeons and other urban exploiters), while many others are making poor habitat choices and consequently decline. We have developed an analytical model to predict: 1) which kinds of environmental change have large, negative effects on fitness (e.g., which is worse: lower average quality or frequency of finding patches?); 2) how species’ evolutionary histories affect their susceptibility to environmental change (are those that are used to rare habitats beforehand less affected?); and 3) how much lost fitness can be recovered via re-adjustment after environmental change (and which scenarios are non-fixable?). In our model, animals search for habitable patches in an otherwise inhospitable matrix. They are assumed to settle when they find a patch which exceeds their threshold of necessary quality. We consider decisions and fitness before environmental change, immediately following change (i.e., if the animals continue to use their existing decision thresholds), and after optimal re-adjustment (e.g., via learning or evolution). We find that decreases in survival during searching (per time step), and declines in habitat quality or availability, generally have stronger negative effects than reduced season duration. Animals that are adapted to good conditions remain choosy after conditions decline and thus suffer more from environmental change than those adapted to poor conditions beforehand. Re-adjustment can recover much of the lost fitness in some situations, such as a reduction in average habitat quality, but re-adjustment recovers much less of the lost fitness when environmental change has reduced habitat availability, or has increased death-rates during the search process. Taken together, these findings increase our ability to predict which species will be more vulnerable to environmental changes and to better prioritize conservation efforts. Abstract Decisions made while searching for settlement sites (e.g., nesting, oviposition) often have major fitness implications. Despite numerous case studies, we lack theory to explain why some species are thriving while others are making poor habitat choices after environmental change. We develop a model to predict: 1) which kinds of environmental change have larger, negative effects on fitness; 2) how evolutionary history affects susceptibility to environmental change; and 3) how much lost fitness can be recovered via re-adjustment after environmental change. We model the common scenario where animals search an otherwise inhospitable matrix, encountering habitats of varying quality, and settling when finding a habitat better than a threshold quality level. We consider decisions and fitness before environmental change, immediately following change (assuming that animals continue to use their previously adaptive decision rules), and after optimal re-adjustment (e.g., via learning or evolution). We find that decreases in survival per time step searching, and declines in habitat quality or availability, generally have stronger negative effects than reduced season duration. Animals that were adapted to good conditions remained choosy after conditions declined and thus suffered more from environmental change than those adapted to poor conditions. Re-adjustment recovered much of the fitness lost through a reduction in average habitat quality, but recovered much less following reductions in habitat availability or survival while searching. Our model offers novel predictions for empiricists to test, as well as suggestions for prioritizing alternative mitigation steps. More forthcoming papers &raquo; <p><strong><a href="https://dx.doi.org/10.1086/702590"><i>Read the Article</i></a></strong></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">C</span>hoosing where to settle is a critical decision various animals have to take, whether it is a bird choosing its nest site, or a fish larvae settling on a home coral. While we know that environmental changes are impacting many habitats and can have major fitness implications, it is harder to predict how these changes in the availability and quality of natural habitats will affect the settlement decisions of different species. A small number of species are actually thriving following environmental changes (e.g. pigeons and other urban exploiters), while many others are making poor habitat choices and consequently decline. We have developed an analytical model to predict: 1) which kinds of environmental change have large, negative effects on fitness (e.g., which is worse: lower average quality or frequency of finding patches?); 2) how species’ evolutionary histories affect their susceptibility to environmental change (are those that are used to rare habitats beforehand less affected?); and 3) how much lost fitness can be recovered via re-adjustment after environmental change (and which scenarios are non-fixable?). In our model, animals search for habitable patches in an otherwise inhospitable matrix. They are assumed to settle when they find a patch which exceeds their threshold of necessary quality. We consider decisions and fitness before environmental change, immediately following change (i.e., if the animals continue to use their existing decision thresholds), and after optimal re-adjustment (e.g., via learning or evolution). We find that decreases in survival during searching (per time step), and declines in habitat quality or availability, generally have stronger negative effects than reduced season duration. Animals that are adapted to good conditions remain choosy after conditions decline and thus suffer more from environmental change than those adapted to poor conditions beforehand. Re-adjustment can recover much of the lost fitness in some situations, such as a reduction in average habitat quality, but re-adjustment recovers much less of the lost fitness when environmental change has reduced habitat availability, or has increased death-rates during the search process. Taken together, these findings increase our ability to predict which species will be more vulnerable to environmental changes and to better prioritize conservation efforts. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">D</span>ecisions made while searching for settlement sites (e.g., nesting, oviposition) often have major fitness implications. Despite numerous case studies, we lack theory to explain why some species are thriving while others are making poor habitat choices after environmental change. We develop a model to predict: 1) which kinds of environmental change have larger, negative effects on fitness; 2) how evolutionary history affects susceptibility to environmental change; and 3) how much lost fitness can be recovered via re-adjustment after environmental change. We model the common scenario where animals search an otherwise inhospitable matrix, encountering habitats of varying quality, and settling when finding a habitat better than a threshold quality level. We consider decisions and fitness before environmental change, immediately following change (assuming that animals continue to use their previously adaptive decision rules), and after optimal re-adjustment (e.g., via learning or evolution). We find that decreases in survival per time step searching, and declines in habitat quality or availability, generally have stronger negative effects than reduced season duration. Animals that were adapted to good conditions remained choosy after conditions declined and thus suffered more from environmental change than those adapted to poor conditions. Re-adjustment recovered much of the fitness lost through a reduction in average habitat quality, but recovered much less following reductions in habitat availability or survival while searching. Our model offers novel predictions for empiricists to test, as well as suggestions for prioritizing alternative mitigation steps. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 04 Feb 2019 06:00:00 GMT “Resolving the measurement uncertainty paradox in ecological management” https://amnat.org/an/newpapers/MayMemarzadeh-A.html The DOI will be https://dx.doi.org/10.1086/702704 Algorithms from robotics can help resolve a long-standing paradox in ecological management under uncertainty Abstract Ecological management and decision-making typically focus on uncertainty about the future, but surprisingly little is known about how to account for uncertainty of the present: that is, the realities of having only partial or imperfect measurements. Our primary paradigms for handling decisions under uncertainty – the precautionary principle and optimal control – have so far given contradictory results. This paradox is best illustrated in the example of fisheries management, where many ideas that guide thinking about ecological decision making were first developed. We find that simplistic optimal control approaches have repeatedly concluded that a manager should increase catch quotas when faced with greater uncertainty about the fish biomass. Current best practices take a more precautionary approach, decreasing catch quotas by a fixed amount to account for uncertainty. Using comparisons to both simulated and historical catch data, we find that neither approach is sufficient to avoid stock collapses under moderate observational uncertainty. Using partially observed Markov decision process (POMDP) methods, we demonstrate how this paradox arises from flaws in the standard theory, which contributes to over-exploitation of fisheries and increased probability of economic and ecological collapse. In contrast, we find POMDP-based management avoids such over-exploitation while also generating higher economic value. These results have significant implications for how we handle uncertainty in both fisheries and ecological management more generally. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/702704 </i></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702704">Read the Article</a></i> </p> --> <p><b>Algorithms from robotics can help resolve a long-standing paradox in ecological management under uncertainty </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">E</span>cological management and decision-making typically focus on uncertainty about the future, but surprisingly little is known about how to account for uncertainty of the present: that is, the realities of having only partial or imperfect measurements. Our primary paradigms for handling decisions under uncertainty &ndash; the precautionary principle and optimal control &ndash; have so far given contradictory results. This paradox is best illustrated in the example of fisheries management, where many ideas that guide thinking about ecological decision making were first developed. We find that simplistic optimal control approaches have repeatedly concluded that a manager should increase catch quotas when faced with greater uncertainty about the fish biomass. Current best practices take a more precautionary approach, decreasing catch quotas by a fixed amount to account for uncertainty. Using comparisons to both simulated and historical catch data, we find that neither approach is sufficient to avoid stock collapses under moderate observational uncertainty. Using partially observed Markov decision process (POMDP) methods, we demonstrate how this paradox arises from flaws in the standard theory, which contributes to over-exploitation of fisheries and increased probability of economic and ecological collapse. In contrast, we find POMDP-based management avoids such over-exploitation while also generating higher economic value. These results have significant implications for how we handle uncertainty in both fisheries and ecological management more generally. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 04 Feb 2019 06:00:00 GMT “Condition-dependent begging elicits increased parental investment in a wild bird population” https://amnat.org/an/newpapers/MayBowers.html Read the Article Are baby birds begging or boasting? Positively condition-dependent begging ultimately enhances offspring survival Altricial young beg for food from their parents across a diverse array of taxa. Expression of this behavior consists of a combination of auditory and visual stimuli, but exactly what offspring are communicating to their parents remains controversial. The most popular hypothesis to explain the functional message encoded by offspring begging postulates that begging signals offspring ‘need’ to parents, and that parents should respond to the degree to which feeding a particular offspring will benefit that individual offspring’s fitness, and, thus, parental fitness. This hypothesis makes several assumptions that are often not satisfied in natural families, raising the possibility that begging offers alternative kinds of information to parents. Here, investigators at the University of Memphis and Illinois State University test the hypothesis that the body condition of nestlings positively affects their begging and, consequently, the parental provisioning of food, offspring growth, and long-term recruitment of offspring into the breeding population. To enhance nestling condition, they experimentally supplemented nestling diets for four days posthatching by pipetting food into their mouths, and also manipulated glucocorticoid levels to simulate the transient increase in corticosterone induced by hunger, believed to mediate begging. In the short term, begging increased with experimental increases in glucocorticoid levels, but this effect depended on nestling satiety. Thus, glucocorticoids promoted begging as an immediate manifestation of offspring hunger. However, days after the food supplementation ended (when there was no effect of glucocorticoid supplementation), previously food-supplemented nestlings were in better condition than non-experimental nestlings and begged for food at an increased rate; their parents, in turn, increased provisioning to a greater extent than parents of non-experimental young, as begging positively predicted food provisioning. Food-supplemented nestlings, therefore, attained above-average pre-fledging body mass, which predicted their recruitment as breeding adults in the local population. Thus, begging signals appear to have communicated offspring condition or quality to parents, eliciting increased parental allocation to enhance offspring survival. Abstract The coevolution of parental supply and offspring demand has long been thought to involve offspring need driving begging and parental care, leaving other hypotheses underexplored. In a population of wild birds, we tested experimentally whether begging serves as a negatively condition-dependent signal of need or a positively condition-dependent signal of quality. Across multiple years, we food-supplemented nestling house wrens shortly after hatching, and simultaneously manipulated corticosterone levels to simulate the hunger-induced increase in glucocorticoids thought to mediate begging. This allowed us also to test whether begging is simply a proximate signal of hunger. Days after supplementation ended, food-supplemented nestlings were in better condition than non-supplemented nestlings and begged for food at an increased rate; their parents, in turn, increased provisioning to a greater extent than parents of non-supplemented young, as begging positively predicted provisioning. Food-supplemented nestlings, therefore, attained above-average condition, which predicted their recruitment as breeding adults in the local population. Glucocorticoids increased begging in the short-term, but this transient effect depended on satiety. Thus, glucocorticoids promoted begging as a proximate response to hunger, whereas the longer-term changes in nestling condition, begging, and food provisioning suggest that begging ultimately signals offspring quality to elicit increased investment, thereby enhancing offspring survival. More forthcoming papers &raquo; <p><a href="https://dx.doi.org/10.1086/702848"><i>Read the Article</i></a></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702848">Read the Article</a></i> </p> --> <p><b>Are baby birds begging or boasting? Positively condition-dependent begging ultimately enhances offspring survival </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>ltricial young beg for food from their parents across a diverse array of taxa. Expression of this behavior consists of a combination of auditory and visual stimuli, but exactly what offspring are communicating to their parents remains controversial. The most popular hypothesis to explain the functional message encoded by offspring begging postulates that begging signals offspring ‘need’ to parents, and that parents should respond to the degree to which feeding a particular offspring will benefit that individual offspring’s fitness, and, thus, parental fitness. This hypothesis makes several assumptions that are often not satisfied in natural families, raising the possibility that begging offers alternative kinds of information to parents. Here, investigators at the University of Memphis and Illinois State University test the hypothesis that the body condition of nestlings positively affects their begging and, consequently, the parental provisioning of food, offspring growth, and long-term recruitment of offspring into the breeding population. To enhance nestling condition, they experimentally supplemented nestling diets for four days posthatching by pipetting food into their mouths, and also manipulated glucocorticoid levels to simulate the transient increase in corticosterone induced by hunger, believed to mediate begging. In the short term, begging increased with experimental increases in glucocorticoid levels, but this effect depended on nestling satiety. Thus, glucocorticoids promoted begging as an immediate manifestation of offspring hunger. However, days after the food supplementation ended (when there was no effect of glucocorticoid supplementation), previously food-supplemented nestlings were in better condition than non-experimental nestlings and begged for food at an increased rate; their parents, in turn, increased provisioning to a greater extent than parents of non-experimental young, as begging positively predicted food provisioning. Food-supplemented nestlings, therefore, attained above-average pre-fledging body mass, which predicted their recruitment as breeding adults in the local population. Thus, begging signals appear to have communicated offspring condition or quality to parents, eliciting increased parental allocation to enhance offspring survival.</p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he coevolution of parental supply and offspring demand has long been thought to involve offspring need driving begging and parental care, leaving other hypotheses underexplored. In a population of wild birds, we tested experimentally whether begging serves as a negatively condition-dependent signal of need or a positively condition-dependent signal of quality. Across multiple years, we food-supplemented nestling house wrens shortly after hatching, and simultaneously manipulated corticosterone levels to simulate the hunger-induced increase in glucocorticoids thought to mediate begging. This allowed us also to test whether begging is simply a proximate signal of hunger. Days after supplementation ended, food-supplemented nestlings were in better condition than non-supplemented nestlings and begged for food at an increased rate; their parents, in turn, increased provisioning to a greater extent than parents of non-supplemented young, as begging positively predicted provisioning. Food-supplemented nestlings, therefore, attained above-average condition, which predicted their recruitment as breeding adults in the local population. Glucocorticoids increased begging in the short-term, but this transient effect depended on satiety. Thus, glucocorticoids promoted begging as a proximate response to hunger, whereas the longer-term changes in nestling condition, begging, and food provisioning suggest that begging ultimately signals offspring quality to elicit increased investment, thereby enhancing offspring survival. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 04 Feb 2019 06:00:00 GMT “Larger area facilitates richness-function effects in experimental microcosms” https://amnat.org/an/newpapers/MayDeLongGibert.html Read the Article Biodiversity ecosystem function and species area curves are linked in experimental island communities Patterns of species diversity, abundance, and their ability to turn over energy and matter (or “function”) at the level of collections of species and their interactions – i.e., ecological communities – are generally viewed as separate properties that require separate explanations. This is strange because the underlying processes determining which individuals of which species conducting which ecological functions in any community must drive the aggregate properties however they are measured. For example, the increase in the number of species with an increase in the area sampled (or a species-area (SAR) curve) or the increase in ecosystem function with an increase in the number of species (or a biodiversity-ecosystem function (BEF) relationship), are central patterns in ecology and are generally treated as separate phenomena. However, the processes determining how many species occur in a place and how much they can do (eat and digest things, turn around energy and matter, etc.) must, at some level, be related. John DeLong and Jean-Philippe Gibert of the University of Nebraska–Lincoln show that these two patterns are indeed linked and together likely emerge from the same underlying processes. The authors constructed experimental microcosms (i.e., tiny constructs that simulate the conditions of freshwater ecosystems in the lab) of protists across a range of Petri dish sizes and measured species richness, abundance, functional diversity, and functioning (carbon and nitrogen content, total biovolume, and oxygen consumption). They found an increase in species richness and oxygen consumption with increasing dish area, indicating that SARs and BEF patterns occur together. Digging into the abundance and functional diversity data, the authors found that the most likely source of both patterns was diversification of niche use (e.g., food types, places to hang out, species they interact with) in the larger dishes that allowed rarer species not to go extinct as often as they do in smaller dishes. The authors also found evidence that higher nutrient turnover – possibly through the action of bacteria – may have contributed to the higher richness and function in larger dishes. Abstract Species-area (SAR) and biodiversity-ecosystem function (BEF) relationships are central patterns in community ecology. Although research on both patterns often invokes mechanisms of community assembly, both SARs and BEFs are generally treated as separate phenomenon. Here we link the two by creating an experimental SAR in microcosm communities and show that greater species richness in larger areas is accompanied by greater ecosystem function. We then explore mechanisms of community assembly by determining whether rare, large, or high biomass species are more likely to persist in the larger microcosms. Our results indicate that larger areas harbor more rare species of a wider range of body sizes and have higher functional diversity, implying that the addition of niche space that supports rare species underlies the effect of area on species richness and function. Our results suggest that the preservation of large areas is a potentially useful way of maximizing the provisioning of ecosystem services through the maintenance of biodiversity. More forthcoming papers &raquo; <p><a href="https://dx.doi.org/10.1086/702705"><i>Read the Article</i></a></p> <!-- <p><i><a href="https://dx.doi.org/10.1086/702705">Read the Article</a></i> </p> --> <p><b>Biodiversity ecosystem function and species area curves are linked in experimental island communities </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>atterns of species diversity, abundance, and their ability to turn over energy and matter (or “function”) at the level of collections of species and their interactions – i.e., ecological communities – are generally viewed as separate properties that require separate explanations. This is strange because the underlying processes determining which individuals of which species conducting which ecological functions in any community must drive the aggregate properties however they are measured. For example, the increase in the number of species with an increase in the area sampled (or a species-area (SAR) curve) or the increase in ecosystem function with an increase in the number of species (or a biodiversity-ecosystem function (BEF) relationship), are central patterns in ecology and are generally treated as separate phenomena. However, the processes determining how many species occur in a place and how much they can do (eat and digest things, turn around energy and matter, etc.) must, at some level, be related. John DeLong and Jean-Philippe Gibert of the University of Nebraska–Lincoln show that these two patterns are indeed linked and together likely emerge from the same underlying processes. </p><p>The authors constructed experimental microcosms (i.e., tiny constructs that simulate the conditions of freshwater ecosystems in the lab) of protists across a range of Petri dish sizes and measured species richness, abundance, functional diversity, and functioning (carbon and nitrogen content, total biovolume, and oxygen consumption). They found an increase in species richness and oxygen consumption with increasing dish area, indicating that SARs and BEF patterns occur together. Digging into the abundance and functional diversity data, the authors found that the most likely source of both patterns was diversification of niche use (e.g., food types, places to hang out, species they interact with) in the larger dishes that allowed rarer species not to go extinct as often as they do in smaller dishes. The authors also found evidence that higher nutrient turnover – possibly through the action of bacteria – may have contributed to the higher richness and function in larger dishes. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">S</span>pecies-area (SAR) and biodiversity-ecosystem function (BEF) relationships are central patterns in community ecology. Although research on both patterns often invokes mechanisms of community assembly, both SARs and BEFs are generally treated as separate phenomenon. Here we link the two by creating an experimental SAR in microcosm communities and show that greater species richness in larger areas is accompanied by greater ecosystem function. We then explore mechanisms of community assembly by determining whether rare, large, or high biomass species are more likely to persist in the larger microcosms. Our results indicate that larger areas harbor more rare species of a wider range of body sizes and have higher functional diversity, implying that the addition of niche space that supports rare species underlies the effect of area on species richness and function. Our results suggest that the preservation of large areas is a potentially useful way of maximizing the provisioning of ecosystem services through the maintenance of biodiversity. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 04 Feb 2019 06:00:00 GMT