UMR 7179 CNRS/MNHN, Département d'Ecologie et de Gestion de la Biodiversité, 57 rue Cuvier, Case postale 55, 75231 Paris Cedex 5, France.
J Exp Biol. 2012 Jul 15;215(Pt 14):2465-70. doi: 10.1242/jeb.069765.
Amphibians are ideal taxa with which to investigate the effects of climate change on physiology, dispersal capacity and distributional ranges as their physiological performance and fitness is highly dependent on temperature. Moreover, amphibians are among the most endangered vertebrate taxa. Here we use the tropical clawed frog, Xenopus tropicalis, as a model system to explore effects of temperature on locomotor performance. Our analyses show that locomotion is thermally sensitive, as illustrated by significant effects of temperature on terrestrial exertion capacity (time until exhaustion) and aquatic burst speed (maximal burst swimming velocity and maximal burst swimming acceleration capacity). Exertion performance measures had relatively lower temperature optima and narrower performance breadth ranges than measures of burst speed. The narrow 80% performance breadths confirm predictions that animals from stable environments should display high thermal sensitivity and, combined with the divergent temperature optima for exertion capacity and burst speed, underscore the vulnerability of tropical species such as X. tropicalis to even relatively small temperature changes. The temperature sensitivity of locomotor performance traits in X. tropicalis suggests that tropical ectotherms may be impacted by predicted changes in climate.
两栖动物是研究气候变化对生理学、扩散能力和分布范围影响的理想分类群，因为它们的生理表现和适应能力高度依赖于温度。此外，两栖动物是最濒危的脊椎动物类群之一。在这里，我们使用热带爪蟾（Xenopus tropicalis）作为模型系统来探索温度对运动表现的影响。我们的分析表明，运动对温度敏感，表现在陆地用力能力（精疲力竭所需的时间）和水生爆发速度（最大爆发游泳速度和最大爆发游泳加速度能力）方面受到温度的显著影响。用力表现测量值的最佳温度较低，表现幅度范围较窄，而爆发速度测量值的最佳温度较高。80%表现幅度较窄的范围证实了这样的预测，即来自稳定环境的动物应该表现出较高的温度敏感性，并且结合用力能力和爆发速度的不同最佳温度，突出了热带物种（如 X. tropicalis）对即使是相对较小的温度变化的脆弱性。X. tropicalis 运动表现特征的温度敏感性表明，热带变温动物可能会受到预测气候变化的影响。
