Muñoz Martha M, Langham Gary M, Brandley Matthew C, Rosauer Dan F, Williams Stephen E, Moritz Craig
Department of Biology, Duke University, Durham, North Carolina, 27708.
National Audubon Society, Washington, District of Columbia.
Evolution. 2016 Nov;70(11):2537-2549. doi: 10.1111/evo.13064. Epub 2016 Sep 27.
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 marked 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 strongly affected by basking behavior: there are two evolutionary optima, with basking species having considerably higher heat tolerance than shade skinks, with no effect of elevation. These distinct responses among traits indicate the multiple selective pressures and constraints that shape the evolution of thermal performance. We discuss how behavior and physiology interact to shape organisms' vulnerability and potential resilience to climate change.
迫切需要了解热带变温动物如何在行为和生理上应对气候变暖。我们研究了晒太阳行为和热环境如何相互作用，以影响来自澳大利亚昆士兰州东北部湿热带地区（AWT）的多种棱蜥属雨林石龙子的热生理进化变异。这些热带蜥蜴在行为上专门利用树冠或阳光，分布在AWT明显的热梯度上。通过系统发育分析，我们证明生理参数要么与当地热栖息地的变化有关，要么与晒太阳行为有关，但并非两者都有关。耐寒性、最佳冲刺速度和性能广度主要受当地热环境影响。具体而言，山地蜥蜴比其低地同类更耐寒，性能广度更广，最佳冲刺温度更高。相比之下，耐热性受晒太阳行为的强烈影响：有两个进化最优值，晒太阳的物种比在阴凉处的石龙子具有更高的耐热性，且不受海拔影响。这些性状之间的不同反应表明了塑造热性能进化的多种选择压力和限制因素。我们讨论了行为和生理如何相互作用，以塑造生物体对气候变化的脆弱性和潜在恢复力。
