Heidi Yang Rose Hills
Investigating Transposable Element Activity in the Adaptive Radiation of Hawaiian Spiders
Adaptive radiations are rapid bursts of diversification of a single ancestor that give rise to many ecologically different species. While the ecological and evolutionary aspects have been extensively studied, little is known about the genomic mechanisms that produce such high genetic and phenotypic diversity. Transposable elements (TEs), DNA sequences that can change their position within a genome, are one potential genomic component, since they can quickly produce a wide variety of mutations when active. McClintock (1984) first proposed that TE activity may increase in response to “challenges to the genome.” Since adaptive radiations frequently occur when a species colonizes a new area, novel environmental and ecological conditions may trigger the deregulation of the genome and activate TEs. Using the adaptive radiation of Tetragnatha spiders, which display various stages of adaptive radiation across several Hawaiian islands, this project will utilize transcriptome data and genomic sequencing methods to test the expectation that TE activity is higher in the youngest branches of the radiation and radiating Hawaiian species have higher TE activity than a non-radiating mainland species.