Data from: Insect size responses to climate change vary across elevations according to seasonal timing

Body size declines are a common response to warming via both plasticity
and evolution, but variable size responses have been observed for
terrestrial ectotherms. We investigate how temperature dependent
development and growth rates in ectothermic organisms induce variation in
size responses. Leveraging long-term data for six montane grasshopper
species spanning 1768 to 3901m, we detect size shifts since ~1960 that
depend on elevation and species’ seasonal timing. Size shifts have been
concentrated at low elevations, with the early emerging species (those
that overwinter as juveniles) increasing in size, while later season
species are becoming smaller. Interannual temperature variation accounts
for the size shifts. The earliest season species may be able to take
advantage of warmer conditions accelerating growth during early spring
development, whereas warm temperatures may adversely impact later season
species via mechanisms such as increased rates of energy use or thermal
stress. Grasshoppers tend to capitalize on warm conditions by both getting
bigger and reaching adulthood earlier. Our analysis further reinforces the
need to move beyond expectations of universal responses to climate change
to consider how environmental exposure and sensitivity vary across
elevations and life histories.