不同经度地区北草蜥的喜好体温和热耐受性

在外温动物热生理特征的进化理论中,“静态”和“易变”是两个持续争论的对立观点。热生理学特征的种内变异是检验此类假设的最有力证据。本研究比较了不同经度地区北草蜥的热环境和热生理特征,以检验“静态”和“易变”假设。东部沿海地区(宁德)的环境温度高于内陆地区(贵阳),与之相适应,沿海地区北草蜥的喜好体温也高于内陆地区。然而,两地区蜥蜴的上临界温度和下临界温度无显著差异。尽管这些热生理学特征的种群间变异趋势并不一致,但是喜好温度随环境温度变化而改变的结果符合“易变”假设的预测。此外,本研究表明蜥蜴的喜好体温存在沿经度方向的地理变异。

Preferred body temperature and thermal tolerance of the northern grass lizard Takydromus septentrionalis from localities with different longitudes

"Static" and "Labile" views of the evolution of thermal physiology in ectotherms have been debated for decades. The most powerful evidence to test the static and labile hypotheses should come from intra-specific studies on thermal physiology. To test these two hypotheses, I compared thermal environments and physiology of a Chinese lacertid lizard Takydromus septentrionalis from two populations with different longitudes. Corresponding to the higher ambient temperatures at the eastern coastal locality, the preferred body temperature of lizards from the coastal locality was higher than that of lizards from the inland locality. Unlike preferred body temperatures, critical thermal maximum (CTmax) and critical thermal minimum (CTmin) did not differ between lizards from the two localities. Although not all characteristics of thermal physiology in T.septentrionalis underwent parallel changes between the populations, the shift of preferred body temperatures as a result of acclimatization to local thermal environments is consistent with the predictions of the labile hypothesis. In addition, this study adds a case that the preferred body temperature of lizards may change along a longitudinal gradientActa Zoologica Sinica 52(3):478-482,2006].