Sieg Annette E, O'Connor Michael P, McNair James N, Grant Bruce W, Agosta Salvatore J, Dunham Arthur E
Department of Biology, Drexel University, Philadelphia, Pennsylvania 19104, USA.
Am Nat. 2009 Nov;174(5):720-33. doi: 10.1086/606023.
Power scaling relationships between body mass and organismal traits are fundamental to biology. Compilations of mammalian masses and basal metabolic rates date back over a century and are used both to support and to assail the universal quarter-power scaling invoked by the metabolic theory of ecology. However, the slope of this interspecific allometry is typically estimated without accounting for intraspecific variation in body mass or phylogenetic constraints on metabolism. We returned to the original literature and culled nearly all unique measurements of body mass and basal metabolism for 695 mammal species and (1) phylogenetically corrected the data using the fullest available phylogeny, (2) applied several different regression analyses, (3) resampled regressions by drawing randomly selected species from each of the polytomies in the phylogenetic hypothesis at each iteration, and (4) ran these same analyses independently on separate clades. Overall, 95% confidence intervals of slope estimates frequently did not include 0.75, and clade-specific slopes varied from 0.5 to 0.85, depending on the clade and regression model. Our approach reveals that the choice of analytical model has a systematic influence on the estimated allometry, but irrespective of the model applied, we find little support for a universal metabolic rate-body mass scaling relationship.
体重与机体特征之间的幂缩放关系是生物学的基础。哺乳动物体重和基础代谢率的汇编可追溯到一个多世纪以前，它们既被用来支持也被用来质疑生态代谢理论所提出的通用四分之一次幂缩放。然而，这种种间异速生长的斜率通常是在不考虑体重的种内变异或代谢的系统发育限制的情况下进行估计的。我们回到原始文献，挑选了695种哺乳动物几乎所有独特的体重和基础代谢测量数据，并且（1）使用最完整的可用系统发育对数据进行系统发育校正，（2）应用几种不同的回归分析，（3）通过在每次迭代中从系统发育假设中的每个多歧分支中随机选择物种对回归进行重采样，以及（4）在不同的进化枝上独立进行这些相同的分析。总体而言，斜率估计的95%置信区间通常不包括0.75，并且特定进化枝的斜率根据进化枝和回归模型的不同在0.5到0.85之间变化。我们的方法表明，分析模型的选择对估计的异速生长有系统性影响，但无论应用何种模型，我们几乎找不到对通用代谢率 - 体重缩放关系的支持。
