Could plasticity mediate highlands lizards’ resilience to climate change? A case study of the leopard iguana (Diplolaemus leopardinus) in Central Andes of Argentina

Abstract

The rising temperature predicted is of main concern for ectotherms because its direct impact on their behavior and physiology. Since physiological performance mediates a species’ resilience to warming exposure, physiological plasticity could greatly reduce the susceptibility to climate change. We studied the degree to which Diplolaemus leopardinus’ lizards are able to adjust behavioral and physiological traits in response to short periods of temperature change. We used a split cross design to measure acclimation response of preferred body temperature (Tp), and thermal performance curve of resting metabolic rate (RMR) and evaporative water loss (EWL). Our results showed that plasticity differs among traits; whereas Tp and EWL showed lower values in warm conditions, RMR increased the temperature at which its value is highest. Moreover, RMR was affected by thermal history, showing a great increase in response to cold exposure in the group initially acclimated to warm. The reduction of EWL and the increase in optimal temperature will give lizards the potential to partially mitigate the impact of rising temperatures in the energy cost and water balance. However, the decrease in Tp and the sensitivity to the warm thermal history in RMR could be detrimental to the energy net gain increasing the species vulnerability, especially considering the increase of heat waves predicted for the next fifty years. The integration of acclimation responses in behavioral and physiological traits provides a better understanding of the range of possible responses of lizards to cope with the upcoming climatic and environmental modifications expected due to climate change.

From performance curves to performance surfaces: Interactive effects of temperature and oxygen availability on aerobic and anaerobic performance in the common wall lizard

“…We processed the data using ExpeData software (version 1.7.30, Sable Systems, Inc.). We extracted the average of the lowest values of gas exchange over a 10‐min interval to estimate RMR, which allows the elimination of elevated metabolic rates due to activity during the measurement period (Kouyoumdjian et al, 2019; Vicenzi et al, 2021). For MMR, we extracted the highest average rate of gas exchange over a 15‐s interval after the robotic insect was activated (Gangloff et al, 2019).…”

Differential Expression of Metabolism-Related Genes in Plateau Pika (Ochotona curzoniae) at Different Altitudes on the Qinghai–Tibet Plateau

“…Thermogenic capacity can be measured as maximum metabolic rate, which is comprised of resting metabolic rate (RMR), shivering thermogenesis (ST), and non-shivering thermogenesis (NST) ( Nespolo et al, 2001 ; Chi and Wang, 2011 ; Mineo et al, 2012 ). Compared with those species inhabiting cold environments, animals inhabiting warm environments, i.e., Meriones unguiculatus and Diplolaemus leopardinus , have a lower RMR ( Ding et al, 2018 ; Vicenzi et al, 2021 ). Similarly, the RMRs of Tupaia belangeri and Chaetops frenatus in winter are usually higher than in summer ( Zhu et al, 2012 ; Oswald et al, 2018 ).…”

Hydric physiology and ecology of a federally endangered desert lizard

“…High temperature and VPD lead to increased CEWL at acute time scales of minutes to hours ( Warburg, 1965 ; Cooper and Withers, 2008 ; Riddell et al. , 2019b ; Vicenzi et al. , 2021 ; Davis et al.…”