Meeting Abstract
Seasonal timing, or phenology, is a critical adaptation that has long served as a model for evolution across spatial, climatic gradients and for rapid evolution in response to changing environments. In animals, however, we have a limited understanding of the genetic variation that facilitates this evolutionary flexibility. The most well-developed studies focus on photoperiodically-cued phenology, whereas there is very little known about the genetic and physiological basis for phenology that is primarily determined by environmental temperature. We used full genome resequencing in combination with a comparative, time series analysis of transcription during the course of diapause (winter dormancy) to explore how a recently derived population of the apple maggot fly, Rhagoletis pomonella, has evolved earlier phenology compared to an ancestral population with relatively later phenology. The results robustly support a polygenic model for phenology, wherein many genetic variants affecting diverse developmental processes lead to a more rapid progression through diapause in the recently evolved population. We link these comparative results with observations from Drosophila melanogaster to further suggest that diapause represents an extreme slowing, but not arrest of development, and that the same variants that may affect the duration of any developmental process also govern the duration of diapause.
