Individuals that inhabit broad elevational ranges may experience unique environmental challenges. Because temperature decreases with increased elevation, the ectotherms living at high elevations have to manage limited activity time and high thermoregulatory effort. The resting metabolic rate (RMR) of a postabsorptive animal is related to its total energy requirements as well as many other fitness traits. Mesquite lizards (Sceloporus grammicus) living on La Malinche Volcano, Mexico, inhabit a wide elevational range with some populations apparently thriving above the tree line. We measured the RMR of lizards from different elevations (i.e., 2,600, 3,200, and 4,100 m) at four ecologically relevant temperatures (i.e., 15, 25, 30, and 35 °C) and found that RMR of mesquite lizards increased with temperature and body mass. More importantly, lizards from the high‐elevation population had mass specific RMR that was higher at all temperatures. While the higher RMRs of high‐elevation populations imply higher metabolic costs at a given temperature these lizards were also smaller. Both of these traits may allow these high elevation populations to thrive in the face of the thermal challenges imposed by their environment.

中文翻译：

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静息代谢率随山地蜥蜴的升高而增加。

居住在高海拔范围内的个人可能会遇到独特的环境挑战。由于温度随着海拔的升高而降低，因此生活在高海拔地区的等温放热必须管理有限的活动时间和较高的温度调节力。吸收后动物的静息代谢率（RMR）与它的总能量需求以及许多其他健康特征有关。豆科灌木蜥蜴（Scoloporus grammicus）居住在墨西哥的拉马林奇火山（La Malinche Volcano）上，海拔高度范围广，一些种群显然在林线以上繁茂。我们在四个与生态相关的温度（即15、25、30和35°C）下测量了不同海拔（即2,600、3,200和4,100 m）的蜥蜴的RMR，发现豆科灌木蜥蜴的RMR随着温度和温度的升高而增加。身体质量。更重要的是，来自高海拔种群的蜥蜴的体重比RMR在所有温度下都更高。虽然高海拔人群的较高RMR意味着在给定温度下较高的代谢成本，但这些蜥蜴也较小。这两个特征都可以使这些高海拔人群在面对其环境带来的热挑战时challenges壮成长。