TY - JOUR
T1 - Cold climate specialization
T2 - Adaptive covariation between metabolic rate and thermoregulation in pregnant vipers
AU - Lourdais, Olivier
AU - Guillon, Michaël
AU - Denardo, Dale
AU - Blouin-Demers, Gabriel
N1 - Funding Information:
We are very grateful to P. Quistinic and F. Quistinic for their assistance in the field. We thank P. Quistinic for the access to the snake facility. This research was made possible by the financial support of the ANR (ECTOCLIM project) , the Programme opérationnel plurirégional Loire FEDER (# PRESAGE 30810 ), the Établissement Public Loire , and the Parc Naturel Régional de Millevaches en Limousin .
PY - 2013/7/2
Y1 - 2013/7/2
N2 - We compared thermoregulatory strategies during pregnancy in two congeneric viperid snakes (Vipera berus and Vipera aspis) with parapatric geographic ranges. V. berus is a boreal specialist with the largest known distribution among terrestrial snakes while V. aspis is a south-European species. Despite contrasted climatic affinities, the two species displayed identical thermal preferences (Tset) in a laboratory thermal gradient. Under identical natural conditions, however, V. berus was capable of maintaining Tset for longer periods, especially when the weather was constraining. Consistent with the metabolic cold adaptation hypothesis, V. berus displayed higher standard metabolic rate at all temperatures considered. We used the thermal dependence of metabolic rate to calculate daily metabolic profiles from body temperature under natural conditions. The boreal specialist experienced higher daily metabolic rate and minimized gestation duration chiefly because of differences in the metabolic reaction norms, but also superior thermoregulatory efficiency. Under cold climates, thermal constraints should make precise thermoregulation costly. However, a shift in the metabolic reaction norm may compensate for thermal constraints and modify the cost-benefit balance of thermoregulation. Covariation between metabolic rate and thermoregulation efficiency is likely an important adaptation to cold climates.
AB - We compared thermoregulatory strategies during pregnancy in two congeneric viperid snakes (Vipera berus and Vipera aspis) with parapatric geographic ranges. V. berus is a boreal specialist with the largest known distribution among terrestrial snakes while V. aspis is a south-European species. Despite contrasted climatic affinities, the two species displayed identical thermal preferences (Tset) in a laboratory thermal gradient. Under identical natural conditions, however, V. berus was capable of maintaining Tset for longer periods, especially when the weather was constraining. Consistent with the metabolic cold adaptation hypothesis, V. berus displayed higher standard metabolic rate at all temperatures considered. We used the thermal dependence of metabolic rate to calculate daily metabolic profiles from body temperature under natural conditions. The boreal specialist experienced higher daily metabolic rate and minimized gestation duration chiefly because of differences in the metabolic reaction norms, but also superior thermoregulatory efficiency. Under cold climates, thermal constraints should make precise thermoregulation costly. However, a shift in the metabolic reaction norm may compensate for thermal constraints and modify the cost-benefit balance of thermoregulation. Covariation between metabolic rate and thermoregulation efficiency is likely an important adaptation to cold climates.
KW - Boreal climate
KW - Ectotherm
KW - Gestation
KW - Metabolism
KW - Thermoregulation
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U2 - 10.1016/j.physbeh.2013.05.041
DO - 10.1016/j.physbeh.2013.05.041
M3 - Article
C2 - 23769691
AN - SCOPUS:84880358976
SN - 0031-9384
VL - 119
SP - 149
EP - 155
JO - Physiology and Behavior
JF - Physiology and Behavior
ER -