Seasonal reproductive endothermy in tegu lizards

Autor(es)

Tattersall, Glenn J. ^{[1, 2]} ; Leite, Cleo A. C. ^{[3, 2]} ; Sanders, Colin E. ^{[3, 4]} ; Cadena, Viviana ^{[1, 5]} ; Andrade, Denis V. ^{[2, 6]} ; Abe, Augusto S. ^{[2, 6]} ; Milsom, William K. ^{[2, 7]}

Afiliação do(s) autor(es)

^[1] Brock Univ, Dept Biol Sci, St Catharines, ON L2S 3A1 - Canada

^[2] Natl Inst Sci & Technol Comparat Physiol INCT Fis, BR-13505060 Sao Paulo - Brazil

^[3] Univ Fed Sao Carlos, Dept Physiol Sci, Sao Paulo - Brazil

^[4] Univ Alberta, Edmonton, AB T6G 2R3 - Canada

^[5] Univ Melbourne, Dept Zool, Melbourne, Vic 3010 - Australia

^[6] Sao Paulo State Univ UNESP, Dept Zool, BR-13506900 Rio Claro - Brazil

^[7] Univ British Columbia, Dept Zool, 6270 Univ Blvd, Vancouver, BC V6T 1Z4 - Canada

• Tipo de documento: Artigo Científico
• Fonte: SCIENCE ADVANCES; v. 2, n. 1 JAN 2016.
• Citações Web of Science: 33

Resumo

With some notable exceptions, small ectothermic vertebrates are incapable of endogenously sustaining a body temperature substantially above ambient temperature. This view was challenged by our observations of nighttime body temperatures sustained well above ambient (up to 10 degrees C) during the reproductive season in tegu lizards (similar to 2 kg). This led us to hypothesize that tegus have an enhanced capacity to augment heat production and heat conservation. Increased metabolic rates and decreased thermal conductance are the same mechanisms involved in body temperature regulation in those vertebrates traditionally acknowledged as ``true endotherms{''}: the birds and mammals. The appreciation that a modern ectotherm the size of the earliest mammals can sustain an elevated body temperature through metabolic rates approaching that of endotherms enlightens the debate over endothermy origins, providing support for the parental care model of endothermy, but not for the assimilation capacity model of endothermy. It also indicates that, contrary to prevailing notions, ectotherms can engage in facultative endothermy, providing a physiological analog in the evolutionary transition to true endothermy. (AU)

• Processo FAPESP: 13/04190-9 - Fisiologia termal e balanço de água em anfíbios anuros ao longo de um gradiente altitudinal da Floresta Atlântica
• Beneficiário: Denis Otavio Vieira de Andrade
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 08/57712-4 - Instituto Nacional de Pesquisas em Fisiologia Comparada
• Beneficiário: Augusto Shinya Abe
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 10/05473-6 - Ecofisiologia de Bokermannohyla alvarengai (Bokermann 1956): uma espécie endêmica de campos rupestres
• Beneficiário: Denis Otavio Vieira de Andrade
• Modalidade de apoio: Auxílio à Pesquisa - Regular