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.

中文翻译：

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北美沙漠西南部塞德罗斯和蒂布隆岛骡鹿的系统地理学

尽管骡鹿（Odocoileus hemionus）在北美分布的大部分地区都存在于强大的种群中，但栖息地丧失、不受管制的狩猎和其他因素已经减少了它们在墨西哥的历史范围。居住在墨西哥沙漠和下加利福尼亚半岛的 6 个假定亚种中的两个受到保护关注，它们占据太平洋中的岛屿（塞德罗斯岛上的 Odocoileus hemionus cerrosensis：濒危）和科尔特斯海（蒂布龙岛上的 Odocoileus hemionus sheldoni：受到威胁）。以西南沙漠 (n = 448) 为重点，我们使用当代样本和自然历史博物馆标本对 Tiburón (n = 22) 和 Cedros (n = 15) 岛骡鹿进行了采样，以完成对该物种复合体的系统地理学评估，并评估这些岛屿亚种的系统地理学。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。贝叶斯天际线图与全新世人口扩张一致。塞德罗斯岛鹿在基因上与邻近的大陆下加利福尼亚鹿最为相似，但表现出一系列独特的单倍型并减少了遗传变异。蒂布龙岛鹿的单倍型出人意料地嵌套在遥远的新墨西哥州发现的大陆血统中，而不是邻近的大陆索诺兰血统。这些发现表明，冰期后气候波动和生物群落更替在西南沙漠骡鹿的系统地理历史中的重要性。我们的遗传数据证实了支持 Cedros 和 Tiburón 鹿的地方性和亚种状态的文化、考古和表型证据。减少遗传变异，