Plasticity in thermal tolerance has limited potential to buffer ectotherms from global warming

Global warming is increasing the overheating risk for many organisms, though the potential for plasticity in thermal tolerance to mitigate this risk is largely unknown. In part, this shortcoming stems from a lack of knowledge about global and taxonomic patterns of variation in tolerance plasticity. To address this critical issue, we test leading hypotheses for broad-scale variation in ectotherm tolerance plasticity using a dataset that includes vertebrate and invertebrate taxa from terrestrial, freshwater and marine habitats. Contrary to expectation, plasticity in heat tolerance was unrelated to latitude or thermal seasonality. However, plasticity in cold tolerance is associated with thermal seasonality in some habitat types. In addition, aquatic taxa have approximately twice the plasticity of terrestrial taxa. Based on the observed patterns of variation in tolerance plasticity, we propose that limited potential for behavioural plasticity (i.e. behavioural thermoregulation) favours the ...全球变暖正加剧诸多生物面临的过热风险，然而学界对热耐受性可塑性缓解该风险的潜力仍知之甚少。这一认知缺口在一定程度上源于学界尚未明晰热耐受性可塑性变异的全球分布与类群分布模式。为解决这一关键科学问题，本研究依托涵盖陆生、淡水与海洋生境的脊椎动物（vertebrate）及无脊椎动物（invertebrate）类群数据集，对外温动物（ectotherm）热耐受性可塑性的大范围变异模式所对应的主流假说开展检验。与预期相悖的是，热耐受性可塑性与纬度或热季节波动并无关联。但在部分生境类型中，冷耐受性可塑性与热季节波动存在显著关联。此外，水生类群的热耐受性可塑性约为陆生类群的两倍。基于观测到的热耐受性可塑性变异模式，本研究提出：行为可塑性（即行为性体温调节）潜力有限的类群更有利于……