Bâtiment d'Anatomie Comparée, UMR 7179-CNRS, Département Adaptations du Vivant, Muséum National d'Histoire Naturelle-Sorbonne Universités (MNHN), 55 rue Buffon, 75005 Paris, France.
Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch 7602, South Africa.
Integr Comp Biol. 2020 Aug 1;60(2):456-466. doi: 10.1093/icb/icaa010.
Temperature is a critical abiotic factor impacting all aspects of the biology of organisms, especially in ectotherms. As such, it is an important determinant of the potential invasive ability of organisms and may limit population expansion unless organisms can physiologically respond to changes in temperature either through plasticity or by adapting to their novel environment. Here, we studied the African clawed frog, Xenopus laevis, which has become invasive on a global scale. We compared adults from an invasive population of western France with individuals from two populations in the native range in South Africa. We measured the thermal dependence of locomotor performance in adults given its relevance to dispersal, predator escape, and prey capture. Our results show significant differences in the limits of the 80% performance breadth interval for endurance with the French population showing a left shift in its limits congruent with the colder climate experienced in France. The French invasive population was introduced only about 40 years ago suggesting a rapid shift in the thermal physiology. Given that all individuals were acclimated under laboratory conditions at 23°C for 2 months this suggests that the invasive frogs have adapted to their new environment. These data may allow the refinement of physiologically informed species distribution models permitting better estimates of future ranges at risk of invasion.
温度是影响生物生物学各个方面的关键非生物因素，尤其是在变温动物中。因此，它是生物体潜在入侵能力的重要决定因素，如果生物体不能通过可塑性或适应新环境来对温度变化做出生理响应，那么温度可能会限制其种群的扩张。在这里，我们研究了已经在全球范围内入侵的非洲爪蟾（Xenopus laevis）。我们比较了来自法国西部入侵种群的成年个体与来自南非本地种群的个体。我们测量了成年个体的运动性能对温度的依赖性，因为这与扩散、逃避捕食者和捕食猎物有关。我们的研究结果表明，在耐力方面的 80%性能幅度区间的限制上存在显著差异，法国种群的限制向左偏移，与法国经历的寒冷气候相一致。法国的入侵种群大约在 40 年前才被引入，这表明其热生理发生了快速转变。考虑到所有个体都在实验室条件下在 23°C 下适应了 2 个月，这表明入侵青蛙已经适应了它们的新环境。这些数据可能允许对生理相关的物种分布模型进行改进，从而更好地估计未来有入侵风险的范围。
