Human predators outpace other agents of trait change in the wild
Human predators outpace other agents of trait change in the wild
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DOI：
10.1073/pnas.0809235106
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发表时间：
2009-01-20
影响因子：
11.1
通讯作者：
Wilmers, Christopher C.
中科院分区：
文献类型：
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作者：
Darimont, Chris T.;Carlson, Stephanie M.;Wilmers, Christopher C.
野生种群的可观察特征不断地被环境和包括捕食者在内的众多自然选择因素所塑造和重塑。与大多数捕食者形成鲜明对比的是，人类现在通常会利用高比例的猎物种群，并以大量处于生殖年龄的成年动物为目标。因此，受到渔民、猎人和植物收割者一致而强烈的“收获选择”的生物可能会在表型上表现出特别迅速和戏剧性的变化。然而，所开发的类群中表型变化的速率相对于其他系统从未进行过比较。在这里，我们表明，40个人类收获的系统的平均表型变化比研究报告的变化要快得多，不仅研究了自然(n=20个系统)，而且研究了其他人类驱动的(n=25个系统)扰动，分别比它们快300%和50%。因此，收获的生物体表现出一些在野生种群中观察到的最突然的特征变化，为表型变化的速度提供了新的认识。这些变化包括与大小相关的特征平均下降近20%，生活史特征变化近25%，在商业开发的系统中变化最快，因此具有深远的保护和经济意义。具体地说，对大小或生活史介导的生态动态产生暂时性快速和重大影响的广泛潜力可能会危及种群、行业和生态系统。
The observable traits of wild populations are continually shaped and reshaped by the environment and numerous agents of natural selection, including predators. In stark contrast with most predators, humans now typically exploit high proportions of prey populations and target large, reproductive-aged adults. Consequently, organisms subject to consistent and strong 'harvest selection' by fishers, hunters, and plant harvesters may be expected to show particularly rapid and dramatic changes in phenotype. However, a comparison of the rate at which phenotypic changes in exploited taxa occurs relative to other systems has never been undertaken. Here, we show that average phenotypic changes in 40 human-harvested systems are much more rapid than changes reported in studies examining not only natural (n = 20 systems) but also other human-driven (n = 25 systems) perturbations in the wild, outpacing them by > 300% and 50%, respectively. Accordingly, harvested organisms show some of the most abrupt trait changes ever observed in wild populations, providing a new appreciation for how fast phenotypes are capable of changing. These changes, which include average declines of almost 20% in size-related traits and shifts in life history traits of nearly 25%, are most rapid in commercially exploited systems and, thus, have profound conservation and economic implications. Specifically, the widespread potential for transitively rapid and large effects on size- or life history-mediated ecological dynamics might imperil populations, industries, and ecosystems.