U.S. Geological Survey, Idaho Cooperative Fish and Wildlife Research Unit, University of Idaho, 875 Perimeter Drive, MS 1141, Moscow, ID, 83844, USA.
Sci Rep. 2022 Jan 11;12(1):535. doi: 10.1038/s41598-021-04449-4.
The genetic composition of an individual can markedly affect its survival, reproduction, and ultimately fitness. As some wildlife populations become smaller, conserving genetic diversity will be a conservation challenge. Many imperiled species are already supported through population augmentation efforts and we often do not know if or how genetic diversity is maintained in translocated species. As a case study for understanding the maintenance of genetic diversity in augmented populations, I wanted to know if genetic diversity (i.e., observed heterozygosity) remained high in a population of gray wolves in the Rocky Mountains of the U.S. > 20 years after reintroduction. Additionally, I wanted to know if a potential mechanism for such diversity was individuals with below average genetic diversity choosing mates with above average diversity. I also asked whether there was a preference for mating with unrelated individuals. Finally, I hypothesized that mated pairs with above average heterozygosity would have increased survival of young. Ultimately, I found that females with below average heterozygosity did not choose mates with above average heterozygosity and wolves chose mates randomly with respect to genetic relatedness. Pup survival was not higher for mated pairs with above average heterozygosity in my models. The dominant variables predicting pup survival were harvest rate during their first year of life and years pairs were mated. Ultimately, genetic diversity was relatively unchanged > 20 years after reintroduction. The mechanism for maintaining such diversity does not appear related to individuals preferentially choosing more genetically diverse mates. Inbreeding avoidance, however, appears to be at least one mechanism maintaining genetic diversity in this population.
个体的遗传组成会显著影响其生存、繁殖,最终影响其适合度。随着一些野生动物种群数量的减少,保护遗传多样性将成为保护的挑战。许多濒危物种已经通过种群增加的努力得到了支持,而我们通常不知道遗传多样性是否或如何在被转移的物种中得以维持。作为了解遗传多样性在增加的种群中维持的案例研究,我想知道在美国落基山脉的狼群在重新引入 20 多年后,遗传多样性(即观察到的杂合度)是否仍然很高。此外,我想知道是否有一种潜在的机制可以维持这种多样性,即遗传多样性低于平均水平的个体选择遗传多样性高于平均水平的伴侣。我还询问了是否存在与不相关个体交配的偏好。最后,我假设具有平均以上杂合度的交配对其幼崽的存活率会增加。最终,我发现杂合度低于平均水平的雌性不会选择杂合度高于平均水平的伴侣,而狼在遗传关系方面随机选择伴侣。在我的模型中,具有平均以上杂合度的交配对的幼崽存活率并没有更高。预测幼崽存活率的主要变量是它们生命的第一年的捕获率以及配对的年份。最终,遗传多样性在重新引入后 20 多年相对保持不变。维持这种多样性的机制似乎与个体优先选择更多遗传多样性的伴侣无关。然而,近亲繁殖的避免至少是维持该种群遗传多样性的一种机制。