The Yucatan Peninsula (YP) is a biotic province located in southeastern Mexico, delimited mainly by climatic variables. One endemic species of the YP is the Yucatan deer mouse Peromyscus yucatanicus. It is considered a member of the P. mexicanus species group, but some morphological characters and habitat preferences separate it from them. Herein, the DNA barcoding identification of P. yucatanicus, intraspecific relationships, and the level of genetic differentiation among its geographical distribution were examined. Sequences of the mitochondrial cytochrome c oxidase subunit 1 gene were used for the phylogenetic, demographic history, and genetic structure analysis. In addition, an ecological niche model was built and transferred to 6000 years ago in order to explore the current and past environmental suitability of the species. Results showed that P. yucatanicus was monophyletic and its phylogenetic relationships unresolved. Intraspecific analyses showed signatures of a scenario of demographic stability followed by population growth, and three genetic haplogroups were identified. Paleontological, paleoclimate, and the results presented here are useful to hypothesize that P. yucatanicus likely diverged in the Pleistocene and invaded the south of YP after the Last Glacial Period with the arrival of the current vegetation in the late Pleistocene—early-middle Holocene, and its demographic population was stable during the remaining Holocene epoch with slight growth at the late-middle Holocene resulting in the major precipitation changes that provided more plant coverage.

中文翻译：

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墨西哥尤卡坦半岛特有的 Peromyscus yucatanicus（啮齿目：仓鼠科）的 DNA 条形码和人口统计历史

尤卡坦半岛 (YP) 是位于墨西哥东南部的一个生物省，主要由气候变量划定。YP 的一种特有物种是尤卡坦鹿鼠 Peromyscus yucatanicus。它被认为是 P. mexicanus 物种组的成员，但一些形态特征和栖息地偏好将其与它们分开。在此，研究了P. yucatanicus 的DNA 条形码识别、种内关系以及其地理分布之间的遗传分化水平。线粒体细胞色素 c 氧化酶亚基 1 基因的序列用于系统发育、人口统计历史和遗传结构分析。此外，还建立了一个生态位模型并将其转移到6000年前，以探索该物种当前和过去的环境适宜性。结果表明，P. yucatanicus 是单系的，其系统发育关系尚未解决。种内分析显示了人口稳定之后人口增长的情景特征，并确定了三个遗传单倍群。古生物学、古气候和此处提供的结果有助于假设 P. yucatanicus 可能在更新世分化并在末次冰期之后随着当前植被在晚更新世 - 早中全新世的到来而侵入 YP 南部，其人口数量在剩余的全新世时期稳定，在全新世晚期中期略有增长，导致降水发生重大变化，提供了更多的植物覆盖。种内分析显示了人口稳定之后人口增长的情景特征，并确定了三个遗传单倍群。古生物学、古气候和此处提供的结果有助于假设 P. yucatanicus 可能在更新世分化并在末次冰期之后随着当前植被在晚更新世 - 早中全新世的到来而侵入 YP 南部，其人口数量在剩余的全新世时期稳定，在全新世晚期中期略有增长，导致降水发生重大变化，提供了更多的植物覆盖。种内分析显示了人口稳定之后人口增长的情景特征，并确定了三个遗传单倍群。古生物学、古气候和此处提供的结果有助于假设 P. yucatanicus 可能在更新世分化并在末次冰期之后随着当前植被在晚更新世 - 早中全新世的到来而侵入 YP 南部，其人口数量在剩余的全新世时期稳定，在全新世晚期中期略有增长，导致降水发生重大变化，提供了更多的植物覆盖。