Teplitsky Céline, Mills James A, Alho Jussi S, Yarrall John W, Merilä Juha
Ecological Genetics Research Unit, Department of Biological and Environmental Sciences, PO Box 65, FI-00014 University of Helsinki, Helsinki, Finland.
Proc Natl Acad Sci U S A. 2008 Sep 9;105(36):13492-6. doi: 10.1073/pnas.0800999105. Epub 2008 Aug 29.
Ecological responses to on-going climate change are numerous, diverse, and taxonomically widespread. However, with one exception, the relative roles of phenotypic plasticity and microevolution as mechanisms in explaining these responses are largely unknown. Several recent studies have uncovered evidence for temporal declines in mean body sizes of birds and mammals, and these responses have been interpreted as evidence for microevolution in the context of Bergmann's rule-an ecogeographic rule predicting an inverse correlation between temperature and mean body size in endothermic animals. We used a dataset of individually marked red-billed gulls (Larus novaehollandiae scopulinus) from New Zealand to document phenotypic and genetic changes in mean body mass over a 47-year (1958-2004) period. We found that, whereas the mean body mass had decreased over time as ambient temperatures increased, analyses of breeding values estimated with an "animal model" approach showed no evidence for any genetic change. These results indicate that the frequently observed climate-change-related responses in mean body size of animal populations might be due to phenotypic plasticity, rather than to genetic microevolutionary responses.
对当前气候变化的生态响应多种多样，在分类学上分布广泛。然而，除了一个例外，表型可塑性和微进化作为解释这些响应的机制，其相对作用在很大程度上尚不清楚。最近的几项研究发现了鸟类和哺乳动物平均体型随时间下降的证据，这些响应在伯格曼法则的背景下被解释为微进化的证据，伯格曼法则是一条生态地理法则，预测恒温动物的温度与平均体型之间呈负相关。我们使用了来自新西兰的个体标记红嘴鸥（Larus novaehollandiae scopulinus）数据集，记录了47年（1958 - 2004年）期间平均体重的表型和遗传变化。我们发现，虽然平均体重随着环境温度的升高而随时间下降，但用“动物模型”方法估计的育种值分析没有显示出任何遗传变化的证据。这些结果表明，动物种群平均体型中频繁观察到的与气候变化相关的响应可能是由于表型可塑性，而不是遗传微进化响应。
