Spatola Gabriella J, Feuerborn Tatiana R, Betz Jennifer A, Buckley Reuben M, Ostrander Gary K, Dutrow Emily V, Velez Alberto, Pinto C Miguel, Harris Alex C, Hale Jessica M, Barnett Bruce D, Mousseau Timothy A, Ostrander Elaine A
National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Biological Sciences, University of South Carolina, Columbia, SC 29028, USA.
National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Curr Biol. 2025 Jan 6;35(1):208-216.e5. doi: 10.1016/j.cub.2024.10.079. Epub 2024 Dec 6.
Free-breeding dogs have occupied the Galápagos Islands at least since the 1830s; however, it was not until the 1900s that dog populations grew substantially, endangering wildlife and spreading disease. In 1981, efforts to control the population size of free-roaming dogs began. Yet, there exist large free-roaming dog populations on the islands of Isabela and Santa Cruz whose ancestry has never been assessed on a genome-wide scale. We thus performed a complete genomic analysis of the current Galápagos dog population, as well as historical Galápagos dogs sampled between 1969 and 2003, testing for population structure, admixture, and shared ancestry. Our dataset included samples from 187 modern and six historical Galápagos dogs, together with whole-genome sequences from over 2,000 modern purebred and village dogs. Our results indicate that modern Galápagos dogs are recently admixed with purebred dogs but show no evidence of a population bottleneck related to the culling. Additionally, identity-by-descent analyses reveal evidence of shared shepherd-dog ancestry in the historical dogs. Overall, our results demonstrate that the 1980s culling of dogs was ineffective in controlling population size and did little to reduce genetic diversity, instead producing a stable and expanding population with genomic signatures of modern purebred dogs. The insights from this study can be used to improve population control strategies for the Galápagos Islands and other endangered endemic communities.
至少从19世纪30年代起，自由繁殖的狗就已占据了加拉帕戈斯群岛；然而，直到20世纪，狗的数量才大幅增长，危及野生动物并传播疾病。1981年，控制自由放养犬数量的工作开始了。然而，在伊莎贝拉岛和圣克鲁斯岛上仍存在大量自由放养的狗，其血统从未在全基因组范围内进行过评估。因此，我们对当前加拉帕戈斯犬种群以及1969年至2003年间采集的历史加拉帕戈斯犬进行了完整的基因组分析，测试种群结构、混合情况和共同祖先。我们的数据集包括187只现代加拉帕戈斯犬和6只历史加拉帕戈斯犬的样本，以及2000多只现代纯种犬和乡村犬的全基因组序列。我们的结果表明，现代加拉帕戈斯犬最近与纯种犬发生了混合，但没有证据表明与捕杀相关的种群瓶颈。此外，同源性分析揭示了历史犬中存在共同牧羊犬祖先的证据。总体而言，我们的结果表明，20世纪80年代对狗的捕杀在控制种群数量方面无效，对减少遗传多样性作用不大，反而产生了一个稳定且不断扩大的种群，具有现代纯种犬的基因组特征。这项研究的见解可用于改进加拉帕戈斯群岛和其他濒危特有群落的种群控制策略。
