AUTHOREA
Log in
Sign Up
Browse Preprints
LOG IN
SIGN UP
Essential Maintenance
: All Authorea-powered sites will be offline 9am-10am EDT Tuesday 28 May
and 11pm-1am EDT Tuesday 28-Wednesday 29 May. We apologise for any inconvenience.
Changku Kang
Public Documents
1
Climate predicts both visible and near-infrared reflectance in butterflies
Changku Kang
and 5 more
February 01, 2021
Climatic gradients frequently predict large-scale ecogeographical patterns in animal coloration, but the underlying causes are often difficult to disentangle. We examined ecogeographical patterns of reflectance among 343 European butterfly species and isolated the role of selection for thermal benefits by comparing visible and near-infrared (NIR) wavebands. NIR light accounts for ~50% of solar energy but cannot be seen by animals so functions primarily in thermal control. We found that reflectance of both dorsal and ventral surfaces shows thermally adaptive correlations with climate. This adaptive variation was more prominent in NIR than visible wavebands and for body regions (thorax-abdomen and basal wings) that are pivotal for thermoregulation. Thermal environments also predicted the reflectance difference between dorsal and ventral surfaces, which may be due to modulation between requirements for heating and cooling. These results highlight the importance of climatic gradients in shaping the reflectance properties of butterflies at a continent-wide scale.