Distinct body-size responses to warming climate in three rodent species

In mammals, body-size responses to warming climates are diverse, and the mechanisms underlying these differentresponses have been little investigated. Using temporal and spatial datasets of three rodent species distributed across different climatic zones in China, we investigated temporal and spatial trends of body size (length and mass), identified the critical drivers of these trends, and inferred the potential causes underlying the distinct body-size responses to the critical drivers. We found that body mass of all species remained stable over time and across space. Body length, however, increased in one species over time and in two species across space. Generally, body-length variation was predicted best by minimum ambient temperature. Moreover, in two species, body length changed linearly with temperature differences between ancestral and colonisation areas. These distinct temperature–length patterns may jointly be caused by species-specific temperature sensitivities and experience...在哺乳动物类群中，机体尺寸对气候变暖的响应模式存在显著差异，而支撑这些差异化响应的内在机制却鲜有研究。本研究依托中国境内不同气候区分布的3种啮齿类的时空数据集，分析了其机体尺寸（体长与体质量）的时空变化趋势，明确了驱动该趋势的关键因子，并推导了不同物种对关键因子产生差异化体型响应的潜在成因。研究结果显示，所有受试物种的体质量均未随时间或空间梯度发生显著变化。但在体长维度上，1个物种的体长随时间显著增加，另有2个物种的体长则随空间梯度发生显著改变。总体而言，体长的变异以最低环境温度作为最佳预测因子。此外，在2个物种中，其体长随祖先分布区与当前定植区域之间的温度差呈线性变化趋势。这些差异化的温度-体长模式，可能由物种特异性的温度敏感性及其所经历的……共同作用所致。