Department of Biology, Indiana State University, Terre Haute, Indiana 47809, USA.
Am Nat. 2010 Aug;176(2):E40-9. doi: 10.1086/653659.
Models of thermal adaptation assume that warm-adapted and cold-adapted organisms can achieve the same fitness, yet recent comparative studies suggest that warm-adapted organisms outperform cold-adapted ones. We explored how this thermodynamic effect on performance might influence selective pressures on thermal physiology. In the absence of a thermodynamic effect, natural selection favors a thermal optimum for performance that closely matches the mean (or modal) body temperature. When warm-adapted organisms outperform cold-adapted organisms, natural selection can favor a thermal optimum that exceeds the mean body temperature. The optimal mismatch between the thermal optimum and the mean temperature increases as does the variation in body temperature within generations. This result holds regardless of whether performance affects fitness through fecundity or survivorship. The selective pressures generated by a thermodynamic effect might explain the substantial mismatch between thermoregulatory behavior and thermal physiology that has been observed in some species.
热适应模型假设，温暖适应和寒冷适应的生物可以达到相同的适应性，但最近的比较研究表明，温暖适应的生物表现优于寒冷适应的生物。我们探讨了这种对性能的热力学效应如何影响对热生理学的选择压力。在没有热力学效应的情况下，自然选择有利于与平均（或模态）体温非常匹配的性能最佳温度。当温暖适应的生物表现优于寒冷适应的生物时，自然选择可以有利于最佳温度超过平均体温。随着世代内体温变化的增加，热最佳温度与平均温度之间的最佳不匹配程度也会增加。无论性能是通过繁殖力还是存活率影响适应性，结果都是如此。热力学效应产生的选择压力可能解释了一些物种中观察到的热调节行为和热生理学之间的显著不匹配。
