Meeting Abstract

94-5  Sunday, Jan. 6 11:00 – 11:15  Genomic perspective of body size evolution in a rattlesnake complex NIKOLAKIS, ZL*; SCHIELD, DR; ORTON, RW; ROW, KR; SMITH, CF; MEIK, JM; WATSON, J; MACKESSY, SP; CASTOE, TA; University of Texas at Arlington; University of Texas at Arlington; University of Texas at Arlington; University of Texas at Arlington; University of Northern Colorado; University of North Texas; University of North Texas; University of Northern Colorado; University of Texas at Arlington zachary.nikolakis@mavs.uta.edu

Identifying the genomic underpinnings of quantitative characters provides unique opportunities to explore the evolution of complex traits, and whether variation in such traits are driven by unique or convergent molecular changes. The western rattlesnake species complex (Crotalus viridis – C. oreganus) represents an excellent model system for studying the evolution of body size across different lineages because there are multiple non-sister lineages that have evolved significantly smaller body sizes. Here we aim to characterize the genomic architecture of body size variation in this group by leveraging population genomic RADseq data across all major lineages of the species complex and a chromosome-level genome assembly of the prairie rattlesnake (C. viridis). We use these data to test for signatures of positive selection within previously identified candidate loci that have been linked to body size variation across vertebrates, including insulin-like growth factor (IGF) and bone morphogenetic protein (BMP) signaling. Results from this study provide insight into the evolution of complex traits in multiple lineages. These results have implications for understanding the degree of canalization of growth pathways in natural populations of vertebrates.