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ASN Awards for Support of Regional Meetings in Ecology, Evolution, and Behavior

Thu, 16 Jan 2025 06:00:00 GMT

The American Society of Naturalists calls for proposals for grants in support of regional conferences and workshops.

ASN offers grants, typically under $2500, to support undergraduate and/or graduate student involvement in (1) topically-broad but regionally-focussed small meetings on ecology and/or evolution and (2) training workshops on more specialized topics within the scope of ASN’s goals to advance the conceptual unification of biology.

These grants are intended to strengthen the valuable role that such regional meetings and workshops can play in the development of younger members of our field. We particularly seek proposals that benefit ASN student members from the grants.

Proposals can be brief, even less than a page. The proposal should indicate the name and intended dates of the meeting or workshop and describe the topical scope of the event. The proposal should indicate how the funds will be used, including a description of how they directly benefit ASN student members. After the event, we request a brief report indicating how funds were used and how students were benefited.

Previous proposals, for example, have paid for reduced registration costs for ASN student members or paid for plenary speakers, for example. For this year in particular, we will also entertain proposals for grants that would enable re-starting meetings delayed by the response to COVID. The event in question should be open to participants from more than a single institution.

Proposals are invited at any time without a fixed deadline. They may be sent to Meredith Zettlemoyer (meredith.zettlemoyer@mso.umt.edu), 2025 chair of the ASN committee for these grants. Please feel free to contact us for informal inquiries or more information.

2024 IDEA Award Winner

Thu, 19 Dec 2024 06:00:00 GMT

Congratulations to the recipient of the 2024 IDEA Award, Dr. Jeremy Yoder! Dr. Yoder was selected for his foundational work recognizing, celebrating, and promoting the inclusion of LGBTQ+ professionals in STEM fields. In 2013, he spearheaded a large-scale study with the nonprofit Out to Innovate to survey more than 1,400 LGBTQA researchers around the world about their experiences in STEM fields. This work produced three papers which together have been cited almost 300 times, have inspired new projects and research, and are used as educational resources. Yoder has presented seminars on inclusion on LGBTQ inclusion and experiences in STEM, and served on panels to review policies for the advancement of LGBTQ+ people in STEM careers. In 2024, he spoke about his career studying Joshua trees in the Story Collider event at the annual Evolution meeting, where he previously helped organize LGBTQ+ meetups and mixers for several years. Learn more about his work on his lab website.

Dr. Yoder will present his work during the IDEA Award Plenary at the in-person portion of the Evolution 2025 meeting in Athens, GA in June 2025. This event will also be live-streamed for all meeting registrants.

The ASN/SSE/SSB Inclusiveness, Diversity, Equity, and Access (IDEA) Award was created in 2019 by the American Society of Naturalists (ASN), the Society for the Study of Evolution (SSE), and the Society of Systematic Biologists (SSB). The IDEA Award is given to a person at any career stage who has strengthened the ecology and evolutionary biology community by promoting inclusiveness and diversity in our fields. The award can also be presented to a group. The recipient receives a plaque at the annual meeting of ASN/SSB/SSE and a $1000 honorarium.

Nominations for the Distinguished Naturalist Award

Wed, 18 Dec 2024 06:00:00 GMT

The ASN seeks nominations (including self-nominations) for the Distinguished Naturalist Award. Nominations are due by 30 January and should consist of a brief statement of suitability for the award, a curriculum vitae, and names and email addresses of three current and/or former trainees of the nominee. To nominate yourself or others please use this Google form; you can also contact President-elect Dan Bolnick with questions or nominations.

We are committed to increasing the diversity of our awardees. Information about these and other ASN awards is here. The names of former recipients can be found here.

The ASN Distinguished Naturalist Award is given to an active investigator in mid-career who has made significant contributions to the knowledge of a particular ecosystem or group of organisms.

Individuals whose research and writing illuminate principles of evolutionary biology and an enhanced aesthetic appreciation of natural history will merit special consideration. The recipient need not be a member of the Society. The award will consist of an especially appropriate work of art and a prize of $2,000.

Nominations for the ASN Award for Distinguished Achievement in the Conceptual Unification of the Biological Sciences

Wed, 18 Dec 2024 06:00:00 GMT

The ASN Award for Distinguished Achievement in the Conceptual Unification of the Biological Sciences, established in 1991, is given annually and honors a senior but still active investigator who is making fundamental contributions to the Society's goals, namely, promoting the conceptual unification of the biological sciences. The award includes an honorarium of $1,000.

The ASN seeks nominations (including self-nominations) for the Award for Distinguished Achievement in the Conceptual Unification of the Biological Sciences. Nominations are due by 30 January and should consist of a brief statement of suitability for the award, a curriculum vitae, and names and email addresses of three current and/or former trainees of the nominee. To nominate yourself or others please use this Google form; you can also contact President-elect Dan Bolnick with questions or nominations.

We are committed to increasing the diversity of our awardees. Information about these and other ASN awards is here. The names of former recipients can be found here.

Applications for the 2025 ASN Early Career Investigator Award

Mon, 16 Dec 2024 06:00:00 GMT

The ASN Early Career Investigator Award honors outstanding promise and accomplishments of early-career investigators who conduct integrative work in the fields of Ecology, Evolutionary Biology, Behavioral Ecology, and Genetics. Applicants working in any of these fields are encouraged to apply.

The award honors outstanding promise and accomplishments of early career investigators (3 years post-PhD, or in the final year of their PhD) who conduct integrative work in ecology, evolution, behavioral ecology, and genetics (see * below). The award was established in 1984 to recognize exceptional work by investigators who received their doctorates in the three years preceding the application deadline, or who are in their final year of graduate school. The award was established in memory of Jasper Loftus-Hills (1946-1974), an Australian biologist of exceptional promise who died tragically during the course of fieldwork three years after receiving his degree.

Winners of this award will present a research paper in the Early Career Investigator’s Symposium at the ASN annual meeting and receive a $700 prize, a travel allowance of $700, cost of registration for the meetings, and a supplement of $500 in case of intercontinental travel. Four awards are made annually. Recipients need not be members of the Society.

In order to apply for this award, applicants should go to this Google form, where they will be asked to answer a few questions and upload their application (see ** below). The application should consist of one PDF, with the following (in this exact order):
- CV (no page limit)
- Research statement (3 page limit, including figures but excluding citations, Arial 11pt or Times New Roman 12pt)
- 3 of your published studies

Additionally, two letters by individuals familiar with the applicant’s work should be uploaded by referees to this Google form (see ** below). Applicants are responsible for ensuring their letter writers submit their letters before the deadline (this can be done before submitting an application), as applications will not be considered complete without these two letters.

* The standard timeframe covers anyone who graduated in 2022, 2023, or 2024, or who plans to defend in 2025. Time since PhD degree can be extended by 1 year for each child born or adopted during this period if the applicant was a primary care giver. Other forms of exceptional care giving responsibility (e.g. partner, spouse, aged parent, etc.) will be considered on a case-by-case basis.

**Applicants and letter writers will be required to sign into an account registered with Google (does not have to be a Gmail address) to upload their applications and letters, respectively. If you or your letter writers do not have a google account, please send materials directly to Martha Muñoz.

Jasper Loftus-Hills (1946-1974) was an Australian biologist of exceptional promise who lost his life doing fieldwork recording frog calls in Texas, three years after receiving his degree from the University of Melbourne. An obituary appeared in Copeia in 1974 (Alexander, Richard D. "Jasper Loftus-Hills." Copeia 1974:812-13).

The Golden Coquí (in the photo above) was discovered on Puerto Rico by George E. Drewry, Kirkland L. Jones, Julia R. Clark, and Jasper J. Loftus-Hills. They had planned to name the species for its color, but when Loftus-Hills was killed in 1974, his colleagues chose instead to name it in his honor.

A further description of Jasper Loftus-Hills appeared in Copeia 2015 (103:467-475), which is a retrospective on his mentor, Murray John Littlejohn (doi: http://dx.doi.org/10.1643/OT-15-274)

The most gifted graduate student Murray ever worked with (in his own estimation) was Jasper Loftus-Hills, whose Ph.D. thesis “Auditory function and acoustic communication in anuran amphibians” was completed in 1971. Jasper followed in Murray’s footsteps to Austin and then went on to Cornell University and the University of Michigan. He was tragically killed by a hit-and-run driver while doing night fieldwork on Gastrophryne in Texas in 1974. The 1992 Gastrophryne paper coauthored by Jasper and Murray is a lucid analysis of the state of the art in character displacement and reinforcement, two terms burdened with a long history of confusion.
(Loftus-Hills, J. J., and M. J. Littlejohn. 1992. Reinforcement and reproductive character displacement inGastrophryne carolinensis and G. olivacea (Anura: Microhylidae): a re-evaluation. Evolution 46:896–906.)

“Evolutionary and Ecological Processes Determining the Properties of the G Matrix”

Thu, 12 Dec 2024 06:00:00 GMT

Steinar Engen and Bernt-Erik Sæther: Read the article

The analyses in this paper show that Fisher's fundamental theorem of natural selection cannot be used to infer the rate of evolutionary responses to changes in the environment due to deterioration effects caused by genetic drift, mutations and environmental fluctuations

How do different evolutionary mechanisms shape phenotypes as the environment changes? Accurately predicting evolutionary responses to shifting environments has been a key challenge throughout the history of evolutionary biology. Indeed, theoretical predictions are sometimes mismatched with observed responses. Steinar Engen and Bernt-Erik Sæther of the Norwegian University of Science and Technology sought to demonstrate the importance of including non-selective processes (e.g., mutation, genetic drift, and environmental fluctuations), which affect a given population’s genetic composition. Not correcting for these processes in previous models may have caused differences between predicted and observed responses.

Engen and Sæther focus on the G matrix for a population, which is the additive genetic variance-covariance matrix for a set of phenotypes on which selection acts. They draw from Lande’s (1979) classical gradient formula and Fisher’s (1930) fundamental theorem of natural selection to decompose the G matrix and the average additive genetic variance of fitness into additive components generated by mutation, drift, and environmental fluctuations (modeled as fluctuations in fitness around a mean vector). Here, a large and stable population size is assumed, with each trait encoded at a single biallelic locus. They expand from Fisher and Lande’s seminal theories to build a model that more sufficiently accounts for the effects of selection over time while correcting for deteriorating effects.

The authors, therefore, formalize Frank’s (2012, p. 47) idea of an approximate conservation law stating that “an increase in the mean fitness of a population caused by natural selection must usually be balanced by an equal and opposite decrease in mean fitness caused by deterioration of the environment.” Indeed, the theory presented demonstrates how the deteriorating effects of mutation, genetic drift, and environmental fluctuations can generate selection because they “generate additive components to the additive genetic variance of fitness in populations at stasis” (Engen and Sæther 2024, p. 13; Figure 1). Interestingly, while the largest eigenvalue and associated eigenvector of the G matrix demonstrate the direction evolution is most likely to occur, the smallest eigenvalues are also revelatory. Processes other than selection produce the smallest eigenvalue greater than 0 and can add considerable additive genetic variance in traits associated with fitness. The associated eigenvector’s loading can indicate the phenotype components that most contribute to fitness.

In summary, Engen and Sæther demonstrate how the G matrix can be broken down into additive components due to selection, mutation, drift, and environmental fluctuations. Their model shows how deteriorating effects can counteract selection. Selection andthe effects of mutation, drift, and environmental fluctuations need to be accounted for together when modeling how populations respond and adapt to changing environments, both in stasis and over time. The authors discuss possible routes of further investigation.

Eleanor Diamant is a Zuckerman Post-doctoral Scholar at Ben Gurion University of the Negev, working with Profs. Uri Roll and Oded Berger-Tal. She is interested in the interaction between human-caused environmental change and wildlife response, specifically birds in the built environment. For her post-doctorate, she is developing a framework to understand how climate shapes biodiversity patterns in urban environments. She is also using fine-scale animal tracking data to determine how climate and weather impact habitat choice and behavior in birds across a landscape mosaic. Beyond the sciences, she enjoys painting, birding, hiking, and B horror movies.

Parasite party: how inbreeding begets a complex life cycle

Thu, 12 Dec 2024 06:00:00 GMT

Jenna M. Hulke and Charles D. Criscione: Read the article

Hulke and Criscione found that high selfing rates for a trematode could be explained solely by demography. Using demographic estimates of selfing, they found no evidence for inbreeding depression. Their study tests a theory for why parasites maintain complex life cycles.

Why are complex life cycles found throughout nature, and how do they arise?

Some familiar examples include crawling caterpillars metamorphosing into airborne butterflies or aquatic tadpoles transforming into land-dwelling toads. Perhaps lesser-known examples are parasites who require multiple hosts, ranging from small invertebrates (snails, molluscs) to larger vertebrates (fish, birds) to complete their life cycles. One specific group of these is Trematoda: parasitic flatworms. Trematodes typically reproduce sexually in a predator host (“definitive” host), who then excretes the parasite’s eggs. These are often consumed by one or more prey hosts (“intermediate” host), where the parasite asexually reproduces. The cycle repeats when the definitive host eats the intermediate host.

How can this particularly complex life cycle be beneficial? Why use multiple hosts when there are so many potential risks along the way, such as transmission failure? A few theories have been put forth in the literature. In 2001, S. P. Brown and colleagues proposed that having multiple hosts and only sexually reproducing in the final host may help parasites avoid reduced fitness in the form of inbreeding depression. Why? Parasite abundance is amplified with each successive transmission up the trophic pyramid. Therefore, there are more available mates in the predator host, reducing the chances of inbreeding. This evolutionary pressure would maintain the complex life cycle of having multiple hosts.

In their article “Testing the mating system model of parasite complex life cycle evolution reveals demographically driven mixed mating,” Hulke and Criscione aimed to empirically test Brown et al.’s theories, something that has been rarely done, by quantifying inbreeding and inbreeding depression in samples of the hermaphroditic trematode Alloglossidium renale. Phylogenetic evidence suggests that A. renale lost its third host, leading to a “truncated” life cycle. This left only the first two intermediate hosts – snail and shrimp – in which to reproduce asexually and sexually, respectively. Hulke and Criscione therefore posited that if Brown et al.’s theories were correct, they would observe the presence of inbreeding but the absence of inbreeding depression in the second host, which would have allowed the third host to be lost over evolutionary time.

The authors collected four sample sets of A. renale (sexually mature individuals living in their second shrimp host) across small bodies of water in Louisiana, Mississippi, and Texas. The authors sequenced their DNA and calculated the genetic selfing rate (sG: the number of individuals produced via selfing) and accounted for false signatures. They then calculated the demographic selfing rate (sD), or the expected “null” rate of selfing, given a randomly mating population. Uniquely, sD was derived from the average infection intensity, or the number of parasites in the focal gland. sG < sD would indicate that fewer genetically inbred individuals were surviving to adulthood, equating to inbreeding depression.

The authors found that sG estimates were both very high and very similar across all sample sets, i.e., all sets had high levels of inbreeding. Additionally, they found no significant differences between sG and sD, i.e., there was no evidence of inbreeding depression across all sets. These findings were in line with Brown et al.’s ideas. A. renale having high levels of inbreeding but no evidence of inbreeding depression lent support to the theory that inbreeding depression avoidance in other multi-host systems could maintain the three-host complex life cycle.

In this article, Hulke and Criscione presented a new method for measuring inbreeding depression in parasite samples collected from the field, removing the necessity of maintaining difficult lab populations and thereby facilitating more studies. Additionally, many theories for the evolution of mixed mating systems invoke selection. However, the authors assert that because their genetic selfing rate matched the “null” demographic expectation, demography is the primary (and perhaps singular) driver of A. renale’s mating system, not natural selection. This study offers an exciting foundation for future studies in evolutionary parasitology. It also challenges us to rethink our assumptions around the relative roles of selection, demography, and random chance in shaping the evolutionary trajectories of the organisms around us.

Faye Romero is a PhD candidate and NSF GRFP Fellow at the University of Rochester in Dr. Nancy Chen’s lab. She is investigating the underlying genetic causes of inbreeding depression in the Federally Threatened Florida Scrub-Jay. Faye is also an avid swing dancer and birdwatcher, and is passionate about increasing accessibility to STEM careers for young people.

“Family Matters: Linking Population Growth, Kin Interactions, and African Elephant Social Groups”

Thu, 12 Dec 2024 06:00:00 GMT

Jasper C. Croll and Hal Caswell: Read the article

Does family matter? Croll and Caswell develop a new approach to integrate family interactions in matrix population models. With this approach, they show that the disruption of African elephant families accelerates the decrease in population growth due to poaching.

While your family members might drive you a little crazy during Thanksgiving dinner or by the end of your two-week vacation, they also likely kept you alive during your childhood and continue to impact your life today. That is because you – like all organisms on earth – are part of a “kinship network”: a group that includes your parents, grandparents, children, grandchildren, siblings, aunts, uncles, and cousins. How this network functions impacts how an individual organism survives and reproduces, a concept termed “life history”. Imagine how you might have been a different person had you grown up within a different family or entirely alone!

Despite the significant role that these familial interactions play in an organism’s life, many current models for the viability of populations only account for interactions at a population level or with direct kin, disregarding the impacts of more distant and complex familial interactions. Jasper Croll and Hal Caswell set out to develop a framework that integrates these crucial feedback mechanisms between the kinship network and an individual’s life history.

Croll and Caswell generated a mathematical model in which an individual’s survival and fertility matrices depend on the kin network. The model frames the kinship network around a single individual named Focal. The kinship network functions as an intermediate level between the individual and the population; imagine a sandwich, where kinship is the meat between two slices of bread.

To demonstrate the utility of this model, Croll and Caswell examined female African elephants as a case study. African elephants are highly social animals, and the females live in family groups led by a matriarch. Previous studies on this species have identified several core familial interactions that Croll and Caswell incorporated into their own model: the presence of a mother improves the juvenile elephant’s survival, the presence of sisters increases the fertility of young female elephants, and older matriarchs increase juvenile survival. The researchers used this model to evaluate how familial interactions impact the effect of poaching on population growth.

The researchers found that the positive effect of family interactions amplifies the negative effect of poaching on population growth because poaching damages the family structure. Essentially, the impact of poaching is actually worse than previous calculations might have predicted because it affects not only the elephant that died, but also all of her family members. For example, one can imagine a young elephant whose mother has died from poaching; this child would have a decreased likelihood of survival. Perhaps less intuitively, even if this young elephant’s sister died, the elephant would have decreased fertility, thereby further reducing the population size.

Croll and Caswell’s work has far-reaching implications in improving future models for ecological predictions and conservation of animal populations. Similar models have even been used to explore the impact of family member’s deaths from COVID-19 in the United States. The significance of the kinship network is applicable across diverse fields, and improving our understanding of these interactions continues to highlight the complex ways in which all life is connected.

Kaleigh Remick is currently a PhD student in the Department of Molecular Biology at Princeton University, where she studies replication of influenza A virus in the te Velthuis Lab. She graduated from Cornell University with a B.A. in biological sciences and a minor in English. When she’s not in lab, you can find her bartending, salsa dancing, tutoring at prisons, conferencing at the Writing Center, eating ice cream, or reading a book!

The battle of the sexes may begin as early as conception

Wed, 04 Dec 2024 06:00:00 GMT

Mathieu Douhard, Eric Baubet, and Marlène Gamelon: Read the article

Mammalian adult females generally live longer than males in the wild, but it is poorly known whether sex differences in prenatal mortality occur, and if so, in what direction. Douhard et al. found a higher embryonic mortality for females than for males in a wild boar population.

The battle of the sexes is occurring within the female body. Previously it was thought that sex ratio at conception and prenatal mortality (embryos missing the implantation window) are biased toward males. Therefore, male embryos were thought to be in excess at conception and experience higher prenatal mortality. A new study by Mathieu Douhard, Eric Baubet, and Marlène Gamelon on French wild boar (Sus scrofa) challenges these classical predictions in wild mammals.

In mammals, prenatal sex ratio prior to implantation is difficult to study. Embryos experiencing prenatal mortality are often reabsorbed by the mother’s body, making it impossible to know if and how many eggs were ovulated. However, female wild boars do not reabsorb the corpus luteus, the outer shell that remains in the mother’s ovary after releasing a mature egg. The authors determined sex ratio of prenatal mortality by dissecting wild boar ovaries, counting the corpora lutea, and comparing this number to the sex ratio of fetuses. Sex ratio at conception was determined using litters with no embryonic mortality. These techniques yielded shocking results.

This study found that sex ratio at conception was not only balanced, but that female rather than male embryos experienced higher prenatal mortality, contradicting classical predictions. The female bias in prenatal mortality was especially skewed in larger litters and was independent of food availability or the mother’s body mass. The authors hypothesize that female embryos develop slower than males after conception, therefore missing the narrow implantation window. This study opens the doors to questioning long-standing predictions of prenatal sex ratio and embryonic mortality and the implications it may have on prenatal competition.

Julia Dovi is a master’s student in the Department of Ecology and Evolution at Stony Brook University. She is passionate about research on animal responses to stress associated with climate change and the genetic mechanisms underlying changes in behavior. She enjoys traveling, playing the piano, and hitting the dance floor.

“Wasted Efforts Impair Random Search Efficiency and Reduce Choosiness in Mate-Pairing Termites”

Tue, 19 Nov 2024 06:00:00 GMT

by Nobuaki Mizumoto (水元惟暁), Naohisa Nagaya (永谷直久), and Ryusuke Fujisawa (藤澤隆介)

Read the Article

Mizumoto et al. reveal that limited energy reduces termite search efficiency but that they compensate for it by lowering partner selectivity. Their study shows animals can't always achieve optimal search strategies, but can adjust their decision-making accordingly...

Imagine you are searching for a soulmate, and you have only a few days remaining to live with a declining energy reserve… Sound stressful? Welcome to the life of termites following their dispersal flights. A new study performed by Dr. Nobuaki Mizumoto and colleagues finds that termites (Reticulitermes speratus) are choosy when they initiate mate searches, but rapidly shift strategies as their energy supplies start to dwindle, settling on the first available partner. The study highlights how diminishing reserves can change search strategies, changing the choosy termite into the pragmatic partner. The work fills in an unexplored gap in search theory by considering the internal condition of the searcher.

Following termite dispersal flights, reproductive individuals shed their wings and search for a mate on foot with limited energy. In general, random search theory predicts that animals searching for mates should ideally maximize their encounter rate. However, this research shows that internal states—such as energy depletion—can push real-world behavior away from optimal searching toward a more flexible strategy.

The researchers monitored termite movement on a specialized omnidirectional "servosphere" treadmill and recorded how search patterns shifted over several days. Immediately following flights, termites were speedy and efficient, pausing very little. By the third day, though, the researchers noticed they had slowed considerably and took frequent breaks. To see how these changes affected encounter rates, researchers ran simulations that showed that termites in the low-energy mode had a lower chance of finding an ideal mate, settling instead for any partner as time passed. Additionally, long searches had fitness costs beyond the energetic ones; termites that searched for longer had reduced survival and lower offspring output than those that paired quickly.

Traditional models for the study of animal search strategies have often assumed that the animals are always behaving optimally. However, this study illustrates how a flexible switch between strategies can help animals cope with internal constraints. By considering the internal state of the individuals, the study provides a more realistic and naturalistic understanding of how animals balance survival and mate choice. The researchers were happy to be able to share these perspectives, especially after an unexpected loss of data and further recovery using data recovery services, underscoring the importance of data backup in science.

By showing how internal energy reserves can influence mate search and choice, termites provide a really fascinating example of real-world search behavior that adapts to both internal and external pressures. Termites remind us that when time runs out, and survival and reproduction get priority, the ideal partner is simply the one you happen to be lucky enough to find.

Purbayan Ghosh is a PhD student working in the lab of Prof. Stephen Pratt at Arizona State University, USA. His research focuses on how behavior and physiology come together during nest site selection in the rock crevice nesting ant Temnothorax rugatulus. When not looking at ants, he enjoys travelling to new places, hiking, playing sports, or hunting down the best food spots in the town.