Data from: A rapidly evolved shift in life history timing during ecological speciation is driven by the transition between developmental phases

For insect species in temperate environments, seasonal timing is often
governed by the regulation of diapause, a complex developmental program
that allows insects to weather unfavorable conditions and synchronize
their lifecycles with available resources. Diapause development consists
of a series of distinct phases including initiation, maintenance,
termination, and post-diapause development. The evolution of insect
seasonal timing depends in part on how these phases of diapause
development and post-diapause development interact to affect variation in
phenology. Here, we dissect the physiological basis of a recently evolved
phenological shift in Rhagoletis pomonella (Diptera: Tephritidae), a model
system for ecological divergence. A recently derived population of R.
pomonella shifted from specializing on native hawthorn fruit to earlier
fruiting introduced apples, resulting in a 3-4 week shift in adult
emergence timing. We tracked metabolic rates of individual flies across
post-winter development to test which phases of development may act either
independently or in combination to contribute to this recently evolved
divergence in timing. Apple and hawthorn flies differed in a number of
facets of their post-winter developmental trajectories. However, divergent
adaptation in adult emergence phenology in these flies was due almost
entirely to the end of the pupal diapause maintenance phase, with
post-diapause development having a very small effect. The relatively
simple underpinnings of variation in adult emergence phenology suggest
that further adaptation to seasonal change in these flies for this trait
might be largely due to the timing of diapause termination unhindered by
strong covariance among different components of post-diapause development.