北草蜥热适应性的生理基础

The Physiological Bases of Thermal Adaptation in the northern Grass Lizard,Takydromus Septentrionalis

以宁德和舟山两个北草蜥种群为研究对象,测定其在相同环境条件下的行为和生理的差异,推测其适应气候变化的潜在对策.在个体水平上,测定了北草蜥的热敏感性,包括不同地理种群的耐受高温（CTmax）和耐受低温（CTmin）,不同温度下的疾跑速度,在生理生化水平上,结合不同温度下呼吸代谢数据来研究种群对热环境的适应.研究结果表明,不同分布区的北草蜥种群的耐受高低温差异显著,舟山蜥蜴的CTmin小于宁德个体,但其CTmax大于宁德个体.两个草蜥种群从18~28℃疾跑速度都随着环境温度的升高而增加,但从28~38℃过程中随温度的升高开始下降,且在相同温度下,舟山北草蜥的跑速较宁德北草蜥快.同样,两个种群的呼吸代谢率均随着温度的升高而呈增加,舟山种群的呼吸代谢水平在不同温度水平均高于宁德种群.呼吸代谢的种群间差异与个体体重差异有关,因为,去除体重差异因素后两个种群的呼吸代谢率无显著差异.

The behavioral and physiological differences between populations of the lizards from two geographically- separated localities of Ningde and Zhoushan are measured,and predictd its potential strategies by which the animal adapt to climate changes. At an individual level,the thermal sensitivity,including critical thermal maximum（ CTmax）,critical thermal minimum（ CTmin）,and sprint speed at different temperatures are measured in different geographic populations. The between- population differences of respiratory metabolism are also determined to examine the adaptation of this lizard in response temperature changes.T. septentrionalis from the two geographic localities show significant differences in CTmax and CTmin.Lizards from Zhoushan had lower CTmin,but higher CTmax than those from Ningde. The sprint speed increases with the increasing temperatures from 18 ℃ to 38 ℃,decrease at the temperature range of 28-38 ℃ in both populations. Moreover,lizards from Zhoushan ran faster than those from Ningde group at same temperatures. The respiratory metabolism increase as the temperature increase in both populations,with higher metabolic rate in Zhoushan lizards than Ningde lizards. However,this between- population difference in respiratory metabolism disappeares after controlling for individual weight,suggesting that the respiratory metabolism was correlated with individual weight.