Data from: It's cool to be dominant: social status alters short-term risks of heat stress

Climate change has potential to trigger social change. As a first step
towards understanding mechanisms determining the vulnerability of animal
societies to rising temperatures, we investigated interactions between
social rank and thermoregulation in three arid-zone bird species:
fawn-coloured lark (Mirafra africanoides, territorial); African red-eyed
bulbul (Pycnonotus nigricans, loosely social) and sociable weaver
(Philetairus socius, complex cooperative societies). We assessed
relationships between body temperature (Tb), air temperature (Ta) and
social rank in captive groups in the Kalahari Desert. Socially dominant
weavers and bulbuls had lower mean Tb than subordinate conspecifics, and
dominant individuals of all species maintained more stable Tb as Ta
increased. Dominant bulbuls and larks tended to monopolise available
shade, but dominant weavers did not. Nevertheless, dominant weavers
thermoregulated more precisely, despite expending no more behavioural
effort on thermoregulation than subordinates. Increasingly unequal risks
associated with heat stress may have implications for stability of animal
societies in warmer climates.