Changing environmental conditions cause changes in the distributions of phenotypic traits in natural populations. However, determining the mechanisms responsible for these changes-and, in particular, the relative contributions of phenotypic plasticity versus evolutionary responses-is difficult. To our knowledge, no study has yet reported evidence that evolutionary change underlies the most widely reported phenotypic response to climate change: the advancement of breeding times. In a wild population of red deer, average parturition date has advanced by nearly 2 weeks in 4 decades. Here, we quantify the contribution of plastic, demographic, and genetic components to this change. In particular, we quantify the role of direct phenotypic plasticity in response to increasing temperatures and the role of changes in the population structure. Importantly, we show that adaptive evolution likely played a role in the shift towards earlier parturition dates. The observed rate of evolution was consistent with a response to selection and was less likely to be due to genetic drift. Our study provides a rare example of observed rates of genetic change being consistent with theoretical predictions, although the consistency would not have been detected with a solely phenotypic analysis. It also provides, to our knowledge, the first evidence of both evolution and phenotypic plasticity contributing to advances in phenology in a changing climate.

中文翻译：

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选择和进化在改变马鹿分娩日期中的作用。

环境条件的变化导致自然种群表型性状的分布发生变化。但是，确定造成这些变化的机制，尤其是表型可塑性相对于进化反应的相对贡献，是困难的。据我们所知，尚无研究报告证据表明进化变化是对气候变化表型反应最广泛的基础：育种时间的延长。在野生马鹿种群中，平均分娩日期在4年中增加了近2周。在这里，我们量化了塑料，人口和遗传成分对这一变化的贡献。特别是，我们量化了直接表型可塑性在温度升高中的作用以及种群结构变化的作用。重要的，我们表明，适应性进化可能在向更早的分娩日期转变中发挥了作用。观察到的进化速率与对选择的反应一致，并且不太可能归因于遗传漂移。我们的研究提供了一个罕见的观察到的遗传变化速率与理论预测相符的例子，尽管仅通过表型分析并不能检测出一致性。就我们所知，它还提供了进化和表型可塑性的第一个证据，这有助于在不断变化的气候中促进物候学的发展。我们的研究提供了一个罕见的例子，说明观察到的遗传变化速率与理论预测相符，尽管仅通过表型分析仍无法检测出一致性。就我们所知，它还提供了进化和表型可塑性的第一个证据，这有助于在不断变化的气候中促进物候学的发展。我们的研究提供了一个罕见的观察到的遗传变化速率与理论预测相符的例子，尽管仅通过表型分析并不能检测出一致性。就我们所知，它还提供了进化和表型可塑性的第一个证据，这有助于在不断变化的气候中促进物候学的发展。