Nagy Kenneth A
University of California, Department of Ecology and Evolutionary Biology, 621 Young Drive South, Los Angeles, CA 90095-1606, USA.
J Exp Biol. 2005 May;208(Pt 9):1621-5. doi: 10.1242/jeb.01553.
The field metabolic rates (FMRs) of 229 species of terrestrial vertebrates, all measured using the doubly labeled water method in free-living individuals, were evaluated. Daily rates of energy expenditure were as low as 0.23 kJ per day in a small reptile (gecko), to as high as 52 500 kJ per day in a marine mammal (seal). This is a range of nearly six orders of magnitude. More than 70% of the variation in log-transformed data is due to variation in body size (expressed as body mass). Much of the remaining variation is accounted for by thermal physiology, with the endothermic mammals and birds having FMRs that are about 12 and 20 times higher, respectively, than FMRs of equivalent-sized, but ectothermic, reptiles. Variation in log(body mass) within each of these three taxonomic classes accounts for over 94% of the variation in log(FMR), and results from nonlinear regression analyses using untransformed data support this conclusion. However, the range of residual variation in mass-adjusted FMR within classes is still more than sixfold (ratio of highest over lowest). Some of this variation is associated with affiliations with lower taxonomic levels (Infraclass: eutherian vs metatherian mammals; Family: passerine, procellariform and galliform birds vs other birds), some is associated with habitat (especially desert vs nondesert), and some with differences in basic diet preference and foraging mode and season. The scaling slopes for FMR often differ from BMR slopes for the same Class of animals, and most differ from the theoretical slope of 0.75. Differences among slopes and intercepts that were detected using conventional regression analyses were largely confirmed upon reanalysis using Independent Contrasts Analysis to adjust for phylogenetic biases.
对229种陆生脊椎动物的野外代谢率（FMRs）进行了评估，所有数据均采用双标水法在自由活动的个体中测得。小型爬行动物（壁虎）的每日能量消耗率低至每天0.23千焦，而海洋哺乳动物（海豹）则高达每天52500千焦。这一范围相差近六个数量级。对数转换后的数据中，超过70%的变异是由于体型差异（以体重表示）。其余大部分变异由热生理学解释，恒温的哺乳动物和鸟类的FMRs分别比同等体型的变温爬行动物高出约12倍和20倍。这三个分类类群中，每个类群的对数（体重）变异占对数（FMR）变异的94%以上，使用未转换数据进行的非线性回归分析结果支持这一结论。然而，各类别中质量调整后的FMR残余变异范围仍超过六倍（最高值与最低值之比）。其中一些变异与较低分类水平的分类归属有关（下纲：真兽亚纲与后兽亚纲哺乳动物；科：雀形目、鹱形目和鸡形目鸟类与其他鸟类），一些与栖息地有关（特别是沙漠与非沙漠），还有一些与基本饮食偏好、觅食方式和季节差异有关。FMR的标度斜率通常与同一类动物的基础代谢率（BMR）斜率不同，且大多与理论斜率0.75不同。使用传统回归分析检测到的斜率和截距差异，在使用独立对比分析重新分析以校正系统发育偏差后，基本得到证实。
