Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
Wildlife Analysis GmbH, Zurich, Switzerland.
Nat Ecol Evol. 2019 Sep;3(9):1359-1364. doi: 10.1038/s41559-019-0968-1. Epub 2019 Sep 2.
Many studies document negative inbreeding effects on individuals, and conservation efforts to preserve rare species routinely employ strategies to reduce inbreeding. Despite this, there are few clear examples in nature of inbreeding decreasing the growth rates of populations, and the extent of population-level effects of inbreeding in the wild remains controversial. Here, we take advantage of a long-term dataset of 26 reintroduced Alpine ibex (Capra ibex ibex) populations spanning nearly 100 years to show that inbreeding substantially reduced per capita population growth rates, particularly for populations in harsher environments. Populations with high average inbreeding (F ≈ 0.2) had population growth rates reduced by 71% compared with populations with no inbreeding. Our results show that inbreeding can have long-term demographic consequences even when environmental variation is large and deleterious alleles may have been purged during bottlenecks. Thus, efforts to guard against inbreeding effects in populations of endangered species have not been misplaced.
许多研究记录了近交对个体的负面影响，保护稀有物种的努力通常采用减少近交的策略。尽管如此，自然界中很少有明确的例子表明近交会降低种群的增长率，并且近交对野生动物种群水平的影响程度仍存在争议。在这里，我们利用一项长达近 100 年的 26 个重新引入的阿尔卑斯野山羊（Capra ibex ibex）种群的长期数据集，表明近交大大降低了每个个体的种群增长率，尤其是在环境更恶劣的种群中。与没有近交的种群相比，平均近交程度较高（F≈0.2）的种群的增长率降低了 71%。我们的研究结果表明，即使环境变化很大，有害等位基因可能在瓶颈期被清除，近交也会对种群产生长期的人口统计学后果。因此，保护濒危物种种群免受近交影响的努力并没有错。
