DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology and Entomology, University of Pretoria 0002, South Africa.
Integr Comp Biol. 2011 Nov;51(5):676-90. doi: 10.1093/icb/icr053. Epub 2011 Jun 20.
Climate change is one of the major issues facing natural populations and thus a focus of recent research has been to predict the responses of organisms to these changes. Models are becoming more complex and now commonly include physiological traits of the organisms of interest. However, endothermic species have received less attention than have ectotherms in these mechanistic models. Further, it is not clear whether responses of endotherms to climate change are modified by variation in thermoregulatory characteristics associated with phenotypic plasticity and/or adaptation to past selective pressures. Here, we review the empirical data on thermal adaptation and acclimatization in endotherms and discuss how those factors may be important in models of responses to climate change. We begin with a discussion of why thermoregulation and thermal sensitivity at high body temperatures should be co-adapted. Importantly, we show that there is, in fact, considerable variation in the ability of endotherms to tolerate high body temperatures and/or high environmental temperatures, but a better understanding of this variation will likely be critical for predicting responses to future climatic scenarios. Next, we discuss why variation in thermoregulatory characteristics should be considered when modeling the effects of climate change on heterothermic endotherms. Finally, we review some biophysical and biochemical factors that will limit adaptation and acclimation in endotherms. We consider both long-term, directional climate change and short-term (but increasingly common) anomalies in climate such as extreme heat waves and we suggest areas of important future research relating to both our basic understanding of endothermic thermoregulation and the responses of endotherms to climate change.
气候变化是自然种群面临的主要问题之一，因此最近的研究重点一直是预测生物体对这些变化的反应。模型变得越来越复杂，现在通常包括感兴趣生物体的生理特征。然而，与变温动物相比，恒温动物在这些机制模型中受到的关注较少。此外，恒温动物对气候变化的反应是否受到与表型可塑性和/或对过去选择压力的适应相关的体温调节特征的变化的影响尚不清楚。在这里，我们回顾了恒温动物中热适应和驯化的经验数据，并讨论了这些因素如何在气候变化反应模型中变得重要。我们首先讨论了为什么体温调节和高温下的热敏感性应该共同适应。重要的是，我们实际上表明，恒温动物耐受高温和/或高温环境的能力存在相当大的差异，但更好地理解这种差异对于预测对未来气候情景的反应可能至关重要。接下来，我们讨论了为什么在对异温恒温动物的气候变化影响进行建模时应考虑体温调节特征的变化。最后，我们回顾了一些将限制恒温动物适应和驯化的生物物理和生化因素。我们既考虑了长期的、定向的气候变化，也考虑了气候的短期（但越来越常见）异常，如极端热浪，并提出了与我们对恒温动物体温调节的基本理解和恒温动物对气候变化的反应有关的重要未来研究领域。
