Greater sensitivity in fish reproductive stages reveals vulnerability to climate change Physiological responses to temperature can provide a window into climate change vulnerability of species. How warm will it get relative to a species' ability to tolerate heat? One complication in answering this question is that an organism's temperature tolerance can change throughout its life span, and organisms in early life stages may be more sensitive to cold and heat extremes than adults (the stage commonly measured) (1, 2). On page 65 of this issue, Dahlke et al. (3) report comparisons of the thermal tolerance limits of almost 700 freshwater and marine fish species at four life stages. Their findings confirm that embryos, and the reproductive adults who produce them, tolerate narrower temperature extremes than larvae and nonspawning adults, with thermal breadths (the difference between upper and lower thermal tolerance) that are narrower by an average of 20°C. As a result of this difference, projected climate vulnerabilities of fishes are greater than previously thought.

中文翻译：

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鱼什么时候会受热？

鱼类繁殖阶段的更高敏感性揭示了对气候变化的脆弱性 对温度的生理反应可以为了解物种的气候变化脆弱性提供一个窗口。相对于一个物种的耐热能力，它会变得多么温暖？回答这个问题的一个复杂问题是，生物体的温度耐受性会在其整个生命周期中发生变化，生命早期阶段的生物体可能比成人（通常测量的阶段）对极端寒冷和炎热更敏感 (1, 2)。在本期第 65 页，Dahlke 等人。(3) 报告了近 700 种淡水和海洋鱼类在四个生命阶段的耐热极限比较。他们的研究结果证实，与幼虫和未产卵的成虫相比，胚胎以及产生它们的生殖成虫能够耐受更窄的极端温度，热宽度（上限和下限之间的差异）平均缩小 20°C。由于这种差异，预计鱼类的气候脆弱性比以前认为的要大。