Comparative genomics reveals convergent evolution among avivorous bats
(Ia io and Nyatalus aviator)
Abstract
Investigating the genetic basis of dietary specialization can provide
insights into the evolution of niche breadth. In this study, we used
comparative genomics methods to analyze two seasonally avivorous bats
(Nyatalus aviator and Ia io) to elucidate the mechanism of adaptation to
the expansion of their dietary niche from insectivory to avivory. Our
findings revealed that genes related to immunity and lipid metabolism
underwent positive selection and convergent evolution among two
avivorous bat species. We also found that immune-related genes in
avivorous bats are under greater compared to bat species with other
diets selective pressure and harbor fewer endogenous retroviral elements
in their genomes. We also found that TLR10 is absent in the two
avivorous bat species. These findings emphasized the significance of
immune-driven adaptive evolution in avivory. Additionally, our results
showed that the dietary evolution of avivorous bats is accompanied by
convergent evolution associated with the PPAR pathway. Notably, CEPT1,
the upstream gene required for the activation of the PPAR pathway,
underwent positive selection and convergence, which may have affected
lipid metabolism. These findings not only provided comprehensive
insights into the adaptive evolution underlying the unique diet of
avivorous bats but also offered novel perspectives on the molecular
mechanisms underlying ecological niche evolution in a dietary context.