vonHoldt Bridgett M, Cahill James A, Fan Zhenxin, Gronau Ilan, Robinson Jacqueline, Pollinger John P, Shapiro Beth, Wall Jeff, Wayne Robert K
Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA.
Sci Adv. 2016 Jul 27;2(7):e1501714. doi: 10.1126/sciadv.1501714. eCollection 2016 Jul.
Protection of populations comprising admixed genomes is a challenge under the Endangered Species Act (ESA), which is regarded as the most powerful species protection legislation ever passed in the United States but lacks specific provisions for hybrids. The eastern wolf is a newly recognized wolf-like species that is highly admixed and inhabits the Great Lakes and eastern United States, a region previously thought to be included in the geographic range of only the gray wolf. The U.S. Fish and Wildlife Service has argued that the presence of the eastern wolf, rather than the gray wolf, in this area is grounds for removing ESA protection (delisting) from the gray wolf across its geographic range. In contrast, the red wolf from the southeastern United States was one of the first species protected under the ESA and was protected despite admixture with coyotes. We use whole-genome sequence data to demonstrate a lack of unique ancestry in eastern and red wolves that would not be expected if they represented long divergent North American lineages. These results suggest that arguments for delisting the gray wolf are not valid. Our findings demonstrate how a strict designation of a species under the ESA that does not consider admixture can threaten the protection of endangered entities. We argue for a more balanced approach that focuses on the ecological context of admixture and allows for evolutionary processes to potentially restore historical patterns of genetic variation.
根据《濒危物种法》(ESA)保护具有混合基因组的种群是一项挑战,该法案被视为美国有史以来最有力的物种保护立法,但缺乏针对杂交种的具体条款。东部狼是一种新确认的类似狼的物种,高度混杂,栖息于五大湖地区和美国东部,该地区此前被认为仅在灰狼的地理分布范围内。美国鱼类和野生动物管理局认为,该地区存在东部狼而非灰狼,是取消灰狼在其整个地理分布范围内的ESA保护(除名)的理由。相比之下,来自美国东南部的红狼是最早受ESA保护的物种之一,尽管与郊狼杂交,但仍受到保护。我们使用全基因组序列数据来证明,东部狼和红狼缺乏独特的祖先,如果它们代表长期分化的北美谱系,这是意料之外的。这些结果表明,将灰狼除名的论点是无效的。我们的研究结果表明,《濒危物种法》下不考虑杂交情况的严格物种指定会如何威胁到对濒危实体的保护。我们主张采取一种更平衡的方法,该方法侧重于杂交的生态背景,并允许进化过程有可能恢复遗传变异的历史模式。