Genome-wide variation and transcriptional changes in diverse developmental processes underly the rapid evolution of seasonality in a temperate fly

Organisms living in seasonal environments must synchronize their growth and reproduction to favorable times of the year. Our study highlights how the timing of dormancy can rapidly evolve to synchronize insects with changes in seasonal food sources. Dormancy is often conceptualized as suspended animation or arrested development, but our results suggest slow, progressive development during dormancy, with the rate of dormancy affected by many genes. Moreover, a population that recently shifted to a food source available earlier in the year has rapidly evolved through changes in many of those same genes. This shows how complex genetics can facilitate adaptation while also leveraging a rapid shift in phenology to understand developmental regulation of dormancy, a fundamental life-history trait in seasonal environments.