Winter wren populations show adaptation to local climate.
Winter wren populations show adaptation to local climate.
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DOI：
10.1098/rsos.160250
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发表时间：
2016-06
影响因子：
3.5
通讯作者：
Pearce-Higgins JW
中科院分区：
文献类型：
--
作者：
Morrison CA;Robinson RA;Pearce-Higgins JW
大多数关于气候变化的进化反应的研究都集中在气候变暖的物候反应上，只提供了进化适应的微弱证据。这可能是因为物候变化与适应度的联系比气候变化影响的更直接机制更弱，例如极端天气事件期间的选择性死亡，这对相关个人的适应度会产生直接影响。研究这些其他机制可能更有可能显示进化适应的证据。为了测试这一点，我们量化的一个小居民雀形目（冬季鹪鹩Troglodytes troglodytes）的冬季严重程度（霜冻天数）的措施区域人口的反应。年种群增长率与这一指标始终呈负相关，但不同种群达到稳定的点（λ = 1）因地区而异，与历史平均霜冻天数密切相关，为当地适应提供了强有力的证据。尽管如此，丰富的区域变化仍然呈负相关的区域平均数的冬季霜冻日，可能是由于一个时间滞后的进化对气候变化的反应速度。正如伯格曼规则所预期的那样，在寒冷的地区，个体弗伦斯更重，这表明局部适应可能是通过身体大小来调节的。然而，没有证据表明在寒冷的年份，小个体的选择性死亡率，平均身体大小的年度变化与冬季霜冻天数无关，因此通过身体大小的变化或其他机制发生局部适应的程度仍然不确定。
Most studies of evolutionary responses to climate change have focused on phenological responses to warming, and provide only weak evidence for evolutionary adaptation. This could be because phenological changes are more weakly linked to fitness than more direct mechanisms of climate change impacts, such as selective mortality during extreme weather events which have immediate fitness consequences for the individuals involved. Studies examining these other mechanisms may be more likely to show evidence for evolutionary adaptation. To test this, we quantify regional population responses of a small resident passerine (winter wren Troglodytes troglodytes) to a measure of winter severity (number of frost days). Annual population growth rate was consistently negatively correlated with this measure, but the point at which different populations achieved stability (λ = 1) varied across regions and was closely correlated with the historic average number of frost days, providing strong evidence for local adaptation. Despite this, regional variation in abundance remained negatively related to the regional mean number of winter frost days, potentially as a result of a time-lag in the rate of evolutionary response to climate change. As expected from Bergmann's rule, individual wrens were heavier in colder regions, suggesting that local adaptation may be mediated through body size. However, there was no evidence for selective mortality of small individuals in cold years, with annual variation in mean body size uncorrelated with the number of winter frost days, so the extent to which local adaptation occurs through changes in body size, or another mechanism remains uncertain.