The contribution of genetic and environmental effects to Bergmann's rule and Allen's rule in house mice

Data associated with the manuscript, "The contribution of genetic and environmental effects to Bergmann's rule and Allen's rule in house mice". Abstract: Distinguishing between genetic, environmental, and genotype-by-environment effects is central to understanding geographic variation in phenotypic clines. Two of the best-documented phenotypic clines are Bergmann's rule and Allen's rule, which describe larger body sizes and shortened extremities in colder climates, respectively. Although numerous studies have found inter- and intraspecific evidence for both ecogeographic patterns, we still have a poor understanding of the extent to which these patterns are driven by genetics, environment, or both. Here, we measured the genetic and environmental contributions to Bergmann's rule and Allen's rule across introduced populations of house mice (Mus musculus domesticus) in the Americas. First, we documented clines for body mass, tail length, and ear length in natural populations, and found that these conform to both Bergmann's rule and Allen's rule. We then raised descendants of wild-caught mice in the lab and showed that these differences persisted in a common environment and are heritable, indicating that they have a genetic basis. Finally, using a full-sib design, we reared mice under warm and cold conditions. We found very little plasticity associated with body size, suggesting that Bergmann's rule has been shaped by strong directional selection in house mice. However, extremities showed considerable plasticity, as both tails and ears grew shorter in cold environments. These results indicate that adaptive phenotypic plasticity as well as genetic changes underlie major patterns of clinal variation in house mice and likely facilitated their rapid expansion into new environments across the Americas. Supplemental data files are provided below. Code associated with the analysis of these data can be found on GitHub at https://github.com/malballinger/Ballinger_allenbergmann_AmNat_2021.

与手稿《家鼠中贝格曼法则（Bergmann's rule）与艾伦法则（Allen's rule）的遗传与环境效应贡献》相关的数据。
摘要：区分遗传效应、环境效应以及基因型-环境互作效应，是理解表型梯度地理变异的核心所在。目前已有两类得到广泛验证的表型梯度模式——贝格曼法则与艾伦法则，前者指寒冷气候下生物体型更大，后者指寒冷气候下生物附肢更短。尽管已有大量研究为这两种生态地理模式提供了种间与种内证据，但我们对这些模式在多大程度上由遗传、环境或二者共同驱动的机制仍不甚明晰。
本研究针对美洲地区引入的家鼠（Mus musculus domesticus）种群，量化了贝格曼法则与艾伦法则的遗传与环境贡献。首先，我们记录了自然种群中体重、尾长与耳长的梯度分布特征，发现其符合贝格曼法则与艾伦法则。随后，我们将野生捕获家鼠的后代饲养于实验室统一环境中，证实这些表型差异依然存在且具有可遗传性，表明其具备遗传基础。最后，我们采用全同胞实验设计，在温暖与寒冷两种环境下饲养家鼠。结果显示，体型相关的可塑性极弱，提示贝格曼法则在家鼠类群中是由强烈的定向选择塑造而成。然而附肢表现出显著的可塑性：在寒冷环境下，尾与耳的长度均显著缩短。上述结果表明，适应性表型可塑性与遗传变化共同构成了家鼠表型梯度变异的主要模式，且可能助力家鼠快速扩散至美洲的各类新环境。
下文提供补充数据文件。本研究数据分析相关代码可在GitHub平台获取，链接为https://github.com/malballinger/Ballinger_allenbergmann_AmNat_2021。