不同发育阶段、性别和种类的黑寡妇蜘蛛的耐热性上限

Temperature strongly influences the physiology and behavior of ectotherms. Persistence within different environments can be limited by thermal tolerances. These thermal tolerances can also shift through life stages and differ between sexes. The critical thermal maximum (CTMax) defines the temperature at which animals experience unorganized locomotion or spasms. In this study, we tested if CTMax varied between a native and an invasive widow species. We separately tested if CTMax varied by widow life stage and sex. We predicted that the invasive species would have higher CTMax due to originally inhabiting warmer climates. We also predicted that juveniles and male widows would possess higher CTMax because they are more mobile and could experience a greater scope of thermal extremes throughout landscapes. We did not find a difference in CTMax between the species, but we did find differences across development stages. Temperature of spasms and death decreased with developmental stages, which corresponds with previous studies in spiders. Future studies of ontogenic and interspecific comparisons will be crucial for more broadly understanding how upper tolerances shapes species persistence in changing climates or ability to invade new habitats.

温度强烈影响变温动物的生理和行为。在不同环境中的持久性可能会受到耐热性的限制。这些耐热性也会随着生命阶段的变化而变化，并且在不同性别之间也会有所不同。临界最高温度(CTMAX)定义为动物陷入无组织运动或痉挛时的温度。在这项研究中，我们测试了土生土长的黑寡妇和外来的黑寡妇蜘蛛物种之间的最大CTmax是否存在差异。我们分别测试了CTmax是否因黑寡妇的生活阶段和性别而不同。我们预测，由于最初居住在较温暖的气候下，入侵物种黑寡妇类群的CTMax值会更高。我们还预测，幼年和雄性黑寡妇将拥有更高的CTX，因为他们活动范围更广（流动性更强），在整个景观中可能经历更大范围的极端高温。我们没有发现不同物种之间（本地与外来之间）的CTMax值有差异，但我们确实发现了黑寡妇蜘蛛在不同发育阶段的CTMax值存在差异。黑寡妇蜘蛛发生痉挛和死亡时温度随着发育阶段的提高而降低（热休克蛋白？？），这与以前对（其他？）蜘蛛的研究相一致。未来对个体发育和种间比较的研究对于更广泛地理解最高耐受性如何塑造物种在变化的气候中的持久性或入侵新栖息地的能力将是至关重要的。

Barnes, C. L., Blay, N. W., & Wilder, S. M. (2019). Upper thermal tolerances of different life stages, sexes, and species of widow spiders (Araneae, Theridiidae). J Insect Physiol, 114, 10-14. doi: 10.1016/j.jinsphys.2019.02.004