Thermal sensitivity of cold climate lizards and the importance of distributional ranges. Zoology

BONINO, M..; D.L. MORENO AZÓCAR; J.A. SCHULTE II; C.S ABDALA Y F.B. CRUZ

ZOOLOGY

ELSEVIER GMBH

Año: 2015 vol. 118 p. 281 - 290

0944-2006

tOne of the fundamental goals in macroecology is to understand the relationship among species? geo-graphic ranges, ecophysiology, and climate; however, the mechanisms underlying the distributionalgeographic patterns observed remain unknown for most organisms. In the case of ectotherms this isparticularly important because the knowledge of these interactions may provide a robust framework forpredicting the potential consequences of climate change in these organisms. Here we studied the rela-tionship of thermal sensitivity and thermal tolerance in Patagonian lizards and their geographic ranges,proposing that species with wider distributions have broader plasticity and thermal tolerance. We pre-dicted that lizard thermal physiology is related to the thermal characteristics of the environment. Wealso explored the presence of trade-offs of some thermal traits and evaluated the potential effects of apredicted scenario of climate change for these species. We examined sixteen species of Liolaemini lizardsfrom Patagonia representing species with different geographic range sizes. We obtained thermal toler-ance data and performance curves for each species in laboratory trials. We found evidence supportingthe idea that higher physiological plasticity allows species to achieve broader distribution ranges com-pared to species with restricted distributions. We also found a trade-off between broad levels of plasticityand higher optimum temperatures of performance. Finally, results from contrasting performance curvesagainst the highest environmental temperatures that lizards may face in a future scenario (year 2080)suggest that the activity of species occurring at high latitudes may be unaffected by predicted climaticchanges.