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

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

ZOOLOGY

ELSEVIER GMBH

Año: 2015 vol. 118 p. 281 - 290

0944-2006

One of the fundamental goals in macroecology is to understand the relationship amongspecies geographic ranges, ecophysiology, and climate; however, the mechanisms underlying thedistributional geographic patterns observed remain unknown for most organisms. In the case ofectotherms this is particularly important because the knowledge of these interactions may provide arobust framework to predict the potential consequences of climate change in these organisms. Here westudied the relationship of thermal sensitivity and thermal tolerance in Patagonian lizards and theirgeographic ranges, proposing that species with wider distributions have broader plasticity and thermaltolerance. We predict that lizard thermal physiology is related to the thermal characteristics of theenvironment. We also explored the presence of trade-offs of some thermal traits, and evaluated thepotential effects of a predicted scenario of climate change for these species. We examined sixteenspecies of Liolaemini lizard from Patagonia representing species with very distinct geographic rangesizes. We obtained thermal tolerance data and performance curves for each species in laboratory trials.We found evidence supporting the idea that higher physiological plasticity allows species to achievebroader distribution ranges compared to species with restricted distributions. We also found a tradeoffbetween broad levels of plasticity and higher optimum temperatures of performance. Finally,results from contrasting performance curves against the highest environmental temperatures thatlizards may face in a future scenario (year 2080) suggest th