California Department of Fish and Wildlife, 715 P Street, Sacramento, CA.
the Behavioral and Molecular Ecology Research Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211.
J Hered. 2021 May 24;112(3):260-275. doi: 10.1093/jhered/esab013.
Though mule deer (Odocoileus hemionus) persist in robust populations throughout most of their North American distribution, habitat loss, unregulated hunting, and other factors have reduced their historical range in México. Two of the 6 putative subspecies inhabiting México's deserts and Baja California peninsula are of conservation concern, occupying islands in the Pacific Ocean (Odocoileus hemionus cerrosensis on Cedros Island: endangered) and Sea of Cortés (Odocoileus hemionus sheldoni on Tiburón Island: threatened). Focusing on the desert southwest (n = 448), we sampled Tiburón (n = 22) and Cedros (n = 15) Island mule deer using contemporary samples and natural history museum specimens to complete a phylogeographic evaluation of the species complex, and assess the phylogeography of these insular subspecies. Both insular subspecies formed endemic haplotype lineages, consistent with island biogeographic theory. Bayesian skyline plots were consistent with Holocene demographic expansion. Cedros Island deer were genetically most similar to adjacent mainland Baja California deer, but exhibited a suite of unique haplotypes and reduced genetic variation. Tiburón Island deer haplotypes unexpectedly nested within a mainland lineage found in distant New Mexico, rather than the adjacent mainland Sonoran lineage. Such findings suggest the importance of postglacial climate fluctuations and biotic community turnover in the phylogeographic history of mule deer in the desert southwest. Our genetic data corroborates cultural, archaeological, and phenotypic evidence supporting Cedros and Tiburón deer endemicity and subspecies status. Reduced genetic variation, divergence from mainland populations, and demographic trends on both islands indicate that conservation, monitoring, and management are critical to ensure persistence of these endemic insular subspecies.
尽管骡鹿（Odocoileus hemionus）在其北美的大部分分布地区都保持着强劲的种群数量，但栖息地的丧失、无管制的狩猎以及其他因素导致其历史分布范围在墨西哥减少。在墨西哥的沙漠和下加利福尼亚半岛栖息的 6 个假定亚种中有两个亚种受到保护关注，它们占据着太平洋（Cedros 岛上的 Odocoileus hemionus cerrosensis：濒危）和科尔特斯海（Tiburón 岛上的 Odocoileus hemionus sheldoni：受威胁）的岛屿。我们专注于西南沙漠地区（n = 448），使用当代样本和自然历史博物馆标本对 Tiburón（n = 22）和 Cedros（n = 15）岛的骡鹿进行采样，完成了对物种复合体的系统地理学评估，并评估了这些岛屿亚种的系统地理学。这两个岛屿亚种都形成了地方性单倍型谱系，与岛屿生物地理学理论一致。贝叶斯天空线图与全新世的人口扩张一致。Cedros 岛的鹿在遗传上与邻近的下加利福尼亚半岛的鹿最相似，但表现出一系列独特的单倍型和减少的遗传变异。Tiburón 岛的鹿的单倍型出人意料地嵌套在新墨西哥州遥远的大陆谱系中，而不是邻近的大陆索诺兰谱系中。这些发现表明，在西南沙漠地区骡鹿的系统地理学历史中，后冰河时代的气候波动和生物群落更替具有重要意义。我们的遗传数据证实了文化、考古和表型证据，支持 Cedros 和 Tiburón 鹿的特有性和亚种地位。遗传变异减少、与大陆种群的分化以及两个岛屿上的人口趋势表明，保护、监测和管理对于确保这些特有岛屿亚种的持续存在至关重要。
