In a 7-year experimental study, we emphasize the co-occurrence of physiological syndromes and phenotypic plasticity in physiological traits related to energy and water budgets in a long-lived ectothermic organism. Using climatic chambers at the CNRS CEBC laboratory in Chizé, we exposed asp vipers (Vipera aspis) to one of three thermal cycles (“warm”,”medium”,”cold”) over 4 years of early life, and then maintained all individuals in a common garden (“medium” cycle) for 3 years of adult life. We repeatedly measured the standard metabolic rate (SMR) and total evaporative water loss (TEWL) of the same individuals over their life, using respirometry systems. We found that individuals experiencing the warm cycle reduced their SMR (negative compensation) but flexibly adjusted their SMR to common garden conditions at adulthood. Thermal conditions during development led to changes in TEWL that persisted until adulthood In addition, plastic responses were combined with a physiological syndrome integrating functional traits related to water and energy balance: SMR and TEWL strongly co-varied both within and among individuals over their lifespan.

Vipera aspis
A wild asp viper (Vipera aspis) photographed by Mathias Dezetter

Long-lived terrestrial ectotherms may cope with ongoing climate changes by combining different pattern of plastic, adaptive responses to temperature variation, and responses to selection on physiological syndromes.

Olivier Lourdais and Andréaz Dupoué from CEBC Chizé designed the study and collected the data. Mathias Dezetter led the data analyses together with Olivier, myself and Andréaz. Find out more in our Functional Ecology paper below

Dezetter, M., Dupoué, A., Le Galliard, J.F. and Lourdais, O. (2021), Additive effects of developmental acclimation and physiological syndromes on lifetime metabolic and water loss rates of a dry-skinned ectotherm. Functional Ecology. Accepted Author Manuscript.