Climate change and temporal trends in body size: the case of rodents

A reduction in body size has been proposed as the third universal ecological response to global warming, after species distributional shifts and phenological changes. However, some recent studies raise doubts about the validity of this pattern, in particular for endotherms. Within this context, here we analyzed data on body mass (mb) for 17 rodent species, covering (at least) the last six decades, together with data on temperature change and basal metabolic rate (BMR) for each species. We found that: 1) ten species (58.8%) showed no significant changes in mb, while the remaining seven species (41.2%) decreased their size during the 20th century; 2) phylogenetic generalized linear mixed models indicate that there is a significant and negative effect of the year of collection on mb; 3) the correlation coefficient between mb and the year of collection (ryear) was not correlated with species mean mb, species distributional range, the length of the time series, or the change in ambient tempe...体型减小已被提出为应对全球变暖的第三种全球性生态响应，仅次于物种分布范围变化与物候变化。然而近期多项研究对该模式的有效性提出了质疑，尤其针对恒温动物（endotherms）。在此研究背景下，本研究分析了覆盖至少过去60年的17种啮齿类物种的体重（body mass，mb）数据，并同步纳入了各物种对应的温度变化与基础代谢率（basal metabolic rate，BMR）数据。本研究结果显示：1）10个物种（占比58.8%）的体重未出现显著变化，剩余7个物种（占比41.2%）在20世纪间体型有所减小；2）系统发育广义线性混合模型（phylogenetic generalized linear mixed models）结果表明，采样年份对体重存在显著负向影响；3）体重与采样年份的相关系数（r_year）并未与物种平均体重、物种分布范围、时间序列长度或环境温度变化……