A membership society whose goal is to advance and to diffuse knowledge of organic evolution and other broad biological principles so as to enhance the conceptual unification of the biological sciences.
The recipient of the ASN Outstanding Student Poster Award, June 2023, is María Paula Toro-Gómez (Universidad del Quindio–EECO) for the poster, “The hidden risk of carrying tadpoles.” Congratulations!
Abstract:
Aposematism is an anti-predator strategy where predators learn to associate the warning signal on prey with an unpleasant experience, and consequently, avoid attacking similar prey in the future. Conspicuous coloration in poison frogs (Dendrobatidae) is considered a warning signal. During parental care, parents transport their tadpoles on the dorsum, which could alter the detectability and recognition of such warning coloration by visually oriented predators. We tested this hypothesis using domestic chicks trained to avoid and discriminate between printed frog models with and without conspicuous-warning coloration. We tested whether the chicks recognized the warning coloration on printed frog models that varied in the quantity of tadpoles on the dorsum. Chicks first attacked frog models without warning coloration, whether they had tadpoles on the dorsum or not. In contrast, frog models with warning coloration were attacked last by chicks. Moreover, the frog models with warning coloration and without tadpoles experienced a lower risk of attack by chicks than similar frog models with tadpoles. However, aposematic frog models maintained the warning function of conspicuous coloration if it was located on parts of the parent's body that are not covered by the tadpoles when transported. Our results suggest that tadpoles on the dorsum of parents might compromise the effectiveness of the warning signal display in poison frogs increasing the risk of attack by visually oriented predators.
Honorable mention for the ASN Outstanding Student Poster Award, June 2023, goes to Allen Xue, University of Texas at Austin, for the poster, “Horizontal Gene Transfer in the Grape Phylloxera.” The award committee notes that this is an undergrad project. Amazing!
Abstract:
Horizontal gene transfer (HGT) is the movement of genes from one organism to another in the absence of reproduction. Although HGT is widespread among bacteria, it can also involve eukaryotes. For example, recent studies have discovered that arthropod genomes can incorporate genes from bacteria, fungi, and even plants through HGT. In this study, we investigated the role of HGT in the evolutionary biology of the grape phylloxera (Daktulosphaira vitifoliae), a major insect pest of grapevines. We assembled the first chromosome-level genome for the phylloxera and validated its size and chromosome number with previous studies. Then, using computational tools, we uncovered two previously undocumented HGT events from bacteria to the phylloxera genome. By performing PCR and analyzing transcriptomes of multiple phylloxera species, we found that these HGT genes were unlikely to be artifacts of bacterial contamination of the DNA sample. Two of the HGT genes encode glycoside hydrolases, which are likely involved in enhancing the insect’s herbivory by helping it break down plant tissue polysaccharides. This finding is in line with previous reports of glycoside hydrolase genes being horizontally transferred from bacteria to other arthropod genomes. Overall, our study found two novel HGTs in the phylloxera genome and highlighted the recruitment of bacterial glycoside hydrolase genes as a repeated process in different arthropod lineages. Our findings also contribute to the broader understanding of the pestilence of the phylloxera and other plant pests at a genomic level.
Photo of Asia Timaria Hightower with poster receiving honorable mention
Honorable mention for the ASN Outstanding Student Poster Award, June 2023, goes to Asia Timaria Hightower, Michigan State University for the poster, “Using Capsella bursa-pastoris to investigate and predict leaf shape variation.” Congratulations!
Abstract:
Anyone who grows houseplants knows that leaves are a great indicator of plant health. For crop breeders, leaves are important for herbicide/pesticide resistance strategies; and for food scientists, leaves are important sources and avenues for nutrient rich diets and famine relief strategies. From the average person to plant biologists, there are two key features of leaves that are always in consideration whether explicitly or implicitly: what do leaves look like (leaf morphology) and how has their shape/color/size changed over time (leaf evolution). Underlying and uniting both key features is the process of leaf development. There have been many studies done in model systems like Arabidopsis thaliana, Zea mays, and Cucumis sativus that have contributed to our current understanding of many of the major genes/pathways in the leaf development process, leaf morphology, and leaf evolution separately. There is significantly less understanding of how those major gene/pathways interact together with other cytogenetic and ecological factors to shape leaf morphology over time; especially in non-model polyploid species like the tetraploid Capsella bursa-pastoris (CBP). To address this gap in knowledge, we are using a novel approach to studying the intersection of leaf morphology, development, and evolution. This approach includes modeling leaf morphology though herbaria specimens of CBP across the United States over a 100-year timespan using morphometric techniques. Historical studies of CBP leaf shape used discrete groups of leaf shape types determined through phenotyping. Through morphometric and dimension reduction techniques, we have found more robust continuous variables that can explain differences in lobing. Through analysis of changes in lobing over time and by climate region, we have found variation to be sustained throughout the contentinal U.S. and different by climate region, in accordance with paleo-lobing patterns. Interestingly, we’ve found lobing to be more affected by climate changes over each accessions growing season, indicating a plastic response in leaf shape. These interesting results will aid us in understanding how CBP has been such a successful invasive species in the U.S. and how responses to climate change can potentially and indirectly affect fitness and establishment for an invasive species.
Limnologist and Past President Ruth Patrick in a stream
The ASN Outstanding Student Poster Award was established in 2012 to recognize a student who has presented an outstanding poster at the annual meeting or at the stand-alone meeting of the American Society of Naturalists.
It was established in memory of Ruth Patrick, a renowned limnologist, past president of the American Society of Naturalists (1975), and Lifetime Honorary Member of the ASN.
