Data from: Colour change on different body regions provides thermal and signalling advantages in bearded dragon lizards

Many terrestrial ectotherms are capable of rapid colour change, yet it is
unclear how these animals accommodate the multiple functions of colour,
particularly camouflage, communication and thermoregulation, especially
when functions require very different colours. Thermal benefits of colour
change depend on an animal's absorptance of solar energy in both
UV–visible (300–700 nm) and near-infrared (NIR; 700–2600 nm) wavelengths,
yet colour research has focused almost exclusively on the former. Here, we
show that wild-caught bearded dragon lizards (Pogona vitticeps) exhibit
substantial UV–visible and NIR skin reflectance change in response to
temperature for dorsal but not ventral (throat and upper chest) body
regions. By contrast, lizards showed the greatest temperature-independent
colour change on the beard and upper chest during social interactions and
as a result of circadian colour change. Biophysical simulations of heat
transfer predicted that the maximum temperature-dependent change in dorsal
reflectivity could reduce the time taken to reach active body temperature
by an average of 22 min per active day, saving 85 h of basking time
throughout the activity season. Our results confirm that colour change may
serve a thermoregulatory function, and competing thermoregulation and
signalling requirements may be met by partitioning colour change to
different body regions in different circumstances.