title: It's cool to be dominant: social status alters short-term risks of heat stress.
abstract: Climate change has the 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 meanTbthan subordinate conspecifics, and dominant individuals of all species maintained more stableTbasTaincreased. 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 the stability of animal societies in warmer climates.
authors.affiliation: FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa susie.j.c@gmail.com.
authors.forename: Susan J
authors.identifier: 0000-0001-9934-2585
authors.initials: SJ
authors.lastname: Cunningham
authors.affiliation: DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Thompson
authors.affiliation: DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: McKechnie
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D001831:Body Temperature; D001833:Body Temperature Regulation / Q000502:physiology*; D046109:Passeriformes / Q000502:physiology*; D012930:Social Dominance; D013019:South Africa
keywords: Climate change; Cooperative breeding; Dominance; Sociality; Stress-induced hyperthermia; Thermoregulation