EBIO Graduate Student, Amanda Hund and Banting Postdoctoral Fellow at the Cornell Lab of Ornithology, Scott Taylor were both awarded at the American Society of Naturalists 2016 conference in Asilomar, CA which took place January 2016. Scott Taylor will be joining the EBIO faculty this coming Fall. Founded in 1883 American Society of Naturalists is the oldest scientific society devoted to the study of ecology, evolution and behavior.
Amanda Hund was awarded the: Ed Ricketts Award for an outstanding student presentation.
Talk Title: Parasite mediated sexual selection and speciation in the barn swallow species complex
Abstract: Many populations are distinguished by sexual traits, yet little is known about how sexual traits diverge and influence speciation. Parasites have been associated with sexual traits in single populations, but it remains unclear how parasites drive sexual trait divergence. To test hypotheses about whether and how female mate choice selects for parasite-mediated advertisement in males, we study a group of closely related populations characterized by sexual trait divergence: the barn swallow species complex. Our comparative work reveals that parasite communities vary across populations and that sexual traits signal information about the most costly parasite. Male color in North America and tail streamers in Europe both correlate with nest mites in a male’s territory. These mites are costly as they impact nestling survival, growth, and future sexual trait expression. We are currently analyzing data on parasite-mediated signaling in a subspecies where females use both streamers and color for mate choice.
Scott Taylor was awarded the: Don Abbott Postdoc Research Award.
Talk Title: Natural selection and the maintenance of reproductive isolation in hybridizing chickadees
Abstract: When locally adapted species meet and interbreed their hybrid offspring often exhibit reduced fitness. Although this is a common pattern, we still lack an understanding of the mechanisms that underlie reduced hybrid fitness in most taxa. Black-capped (Poecile atricapillus), Carolina (P. carolinensis), and mountain (P. gambeli) chickadees hybridize where their ranges overlap. These species differ in physiological traits that contribute to aerobic capacity and basal metabolism, and preliminary data indicate that selection against hybrids may be related to genetic incompatibilities in core metabolic pathways. We sequenced RNA from five individuals of each species, assembled species-specific transcriptomes, and assessed sequence variation. Results of enrichment analyses indicate that multiple pathways involved in aerobic capacity (e.g., OXPHOS, lipid metabolism, glycolysis) are significantly enriched for fixed differences between the species. We hypothesize that a breakdown in aerobic capacity in hybrid chickadees due to these sequence differences may be facilitating maintenance of reproductive isolation.
Congratulations Amanda and Scott!
