Basking behavior predicts the evolution of heat tolerance in Australian rainforest lizards

There is pressing urgency to understand how tropical ectotherms can behaviorally and physiologically respond to climate warming. We examine how basking behavior and thermal environment interact to influence evolutionary variation in thermal physiology of multiple species of lygosomine rainforest skinks from the Wet Tropics of northeastern Queensland, Australia (AWT). These tropical lizards are behaviorally specialized to exploit canopy or sun, and are distributed across steep thermal clines in the AWT. Using phylogenetic analyses, we demonstrate that physiological parameters are either associated with changes in local thermal habitat or to basking behavior, but not both. Cold tolerance, the optimal sprint speed, and performance breadth are primarily influenced by local thermal environment. Specifically, montane lizards are more cool tolerant, have broader performance breadths, and higher optimum sprinting temperatures than their lowland counterparts. Heat tolerance, in contrast, is stro...当前亟需厘清热带外温动物（ectotherms）如何通过行为与生理层面响应气候变暖。本研究探讨晒背行为与热环境如何共同作用，影响澳大利亚昆士兰州东北部湿热带区（Australian Wet Tropics，简称AWT）内多种光蜥亚科（Lygosominae）雨林石龙子的热生理演化变异。这些热带蜥蜴在行为上特化利用林冠遮阴或直射阳光，且分布于AWT内陡峭的热梯度环境中。通过系统发育分析，本研究发现：蜥蜴的生理参数仅与当地热生境变化或晒背行为二者之一相关，而非同时受两者调控。耐寒性、最佳疾跑速度以及性能广度主要受当地热环境调控。具体而言，山地蜥蜴较低海拔同类具有更强的耐寒性、更宽的性能广度以及更高的最佳疾跑温度。与之相反，耐热性则