Thermally variable environments are particularly challenging for ectotherms as physiological functions are thermo-dependent. As a consequence, ectotherms in highly seasonal environments are predicted to have greater thermal plasticity. However, much of our understanding of thermal plasticity comes from controlled experiments in a laboratory setting. Relatively fewer studies investigate thermal plasticity in free-ranging animals living in their natural environment. We investigated the presence of thermal plasticity within a single activity season in adult males of a natural high elevation population of White's skink (Liopholis whitii) in south-eastern Australia. This species lives in a permanent home site (rock crevice and/or burrow), facilitating the repeated capture of the same individuals across the activity season. We monitored the thermal variation across the field site and over the activity season, and tested thermal tolerances and performance of male L. whitii on three occasions across their activity season. Maximum and average temperatures varied across the field site, and temperatures gradually increased across the study period. Evidence of temporal plasticity was identified in the critical thermal minimum and thermal tolerance breadth, but not in the critical thermal maximum. Thermal performance was also found to be plastic, but no temporal patterns were evident. Our temporal plasticity results are consistent which much of the previous literature, but this is one of the first studies to identify these patterns in a free-ranging population. In addition, our results indicate that performance may be more plastic than previous literature suggests. Overall, our study highlights the need to pair laboratory and field studies in order to understand thermal plasticity in an ecologically relevant context.

中文翻译：

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自由放养的亚高山蜥蜴热塑性的时间变化

由于生理功能依赖于温度，因此热变环境对变温动物尤其具有挑战性。因此，预测高度季节性环境中的变温线具有更大的热可塑性。然而，我们对热塑性的理解大部分来自实验室环境中的受控实验。相对较少的研究调查生活在自然环境中的自由放养动物的热可塑性。我们调查了澳大利亚东南部白石龙子 (Liopholis whitii) 自然高海拔种群的成年雄性在单个活动季节中是否存在热可塑性。该物种生活在一个永久的栖息地（岩石裂缝和/或洞穴），便于在整个活动季节重复捕获相同的个体。我们监测了整个野外现场和整个活动季节的热变化，并在其活动季节的三个场合测试了雄性 L. whitii 的热耐受性和性能。整个现场的最高和平均温度各不相同，并且在整个研究期间温度逐渐升高。在临界热最小值和热耐受宽度中确定了时间塑性的证据，但未在临界热最大值中确定。还发现热性能是可塑性的，但没有明显的时间模式。我们的时间可塑性结果与之前的大部分文献一致，但这是在自由放养人群中识别这些模式的首批研究之一。此外，我们的结果表明，性能可能比以前的文献所建议的更具可塑性。全面的，