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Estimates of organismal thermal tolerance are frequently used to assess physiological risk from warming, yet the assumption that these estimates are predictive of mortality has been called into question. We tested this assumption in the cold-water-specialist frog, Ascaphus montanus . For seven populations, we used dynamic experimental assays to measure tadpole critical thermal maximum (CTmax) and measured mortality from chronic thermal stress for 3 days at different temperatures. We tested the relationship between previously estimated population CTmax and observed mortality, as well as the strength of CTmax as a predictor of mortality compared to local stream temperatures capturing varying timescales. Populations with higher CTmax experienced significantly less mortality in the warmest temperature treatment (25°C). We also found that population CTmax outperformed stream temperature metrics as the top predictor of observed mortality. These results demonstrate a clear link between CTmax and mortality from thermal stress, contributing evidence that CTmax is a relevant metric for physiological vulnerability assessments. 

Abstract Adaptive plasticity in thermal tolerance traits may buffer organisms against changing temperatures, making such responses of particular interest in the face of global climate change. Although population variation is integral to the evolvability of this trait, many studies inferring proxies of physiological vulnerability from thermal tolerance traits extrapolate data from one or a few populations to represent the species. Estimates of physiological vulnerability can be further complicated by methodological effects associated with experimental design. We evaluated how populations varied in their acclimation capacity (i.e., the magnitude of plasticity) for critical thermal maximum (CTmax) in two species of tailed frogs (Ascaphidae), cold‐stream specialists. We used the estimates of acclimation capacity to infer physiological vulnerability to future warming. We performed CTmax experiments on tadpoles from 14 populations using a fully factorial experimental design of two holding temperatures (8 and 15°C) and two experimental starting temperatures (8 and 15°C). This design allowed us to investigate the acute effects of transferring organisms from one holding temperature to a different experimental starting temperature, as well as fully acclimated responses by using the same holding and starting temperature. We found that most populations exhibited beneficial acclimation, where CTmax was higher in tadpoles held at a warmer temperature, but populations varied markedly in the magnitude of the response and the inferred physiological vulnerability to future warming. We also found that the response of transferring organisms to different starting temperatures varied substantially among populations, although accounting for acute effects did not greatly alter estimates of physiological vulnerability at the species level or for most populations. These results underscore the importance of sampling widely among populations when inferring physiological vulnerability, as population variation in acclimation capacity and thermal sensitivity may be critical when assessing vulnerability to future warming. 

【摘要】 全球高等教育机构的科学家们都认识到了通过与公众利益相关者交流来分享他们的热情, 解释他们的科学研究, 并鼓励中小学生进入科学领域的重要性。然而, 如果不直接考虑学生和教师的观点和兴趣, 科学家可能会围绕自己的目标来设计活动, 从而限制了其对学校利益相关者 (即学生、教师、辅助人员、学生家长和其他看护者) 的影响力。我们根据自然科学和社会科学的研究, 描述了如何将地域的概念扩展到生物物理学之外, 来帮助学校利益相关者以有意义地参与活动。本研究描述了我们开发的多维 PLACE 框架, 以整合所有利益相关者在参与计划中的观点、知识和价值观。该框架是围绕利益相关者为确保成功的合作关系而应在早期讨论的主题所构建的。我们建议科学家确定并使用具有包容性的教学方法、采取以对话式交流方法为框架的语言、建立以参与为中心的目标和动机、应用关于地域的丰富文化知识 (即学科、个人或经验知识), 以及利用有意义的指标进行参与评估。 我们还介绍了两个案例研究, 以说明 PLACE 框架的组成部分, 以及如何利用它建立科学家和学校之间强有力的、成功的合作关系。 【翻译: 胡怡思; 审校: 聂永刚】