Data from: Populations at risk: conservation genetics of kangaroo mice (Microdipodops) of the Great Basin Desert

The Great Basin Desert of western North America has experienced frequent habitat alterations due to a complex biogeographic history and recent anthropogenic impacts, with the more recent alterations likely resulting in the decline of native fauna and flora. Dark (Microdipodops megacephalus) and pallid (M. pallidus) kangaroo mice are ecological specialists found within the Great Basin Desert and are potentially ideal organisms for assessing ecosystem health and inferring the biogeographic history of this vulnerable region. Herein, newly acquired nuclear-encoded microsatellite loci were utilized to assess patterns of variation within and among spatially discrete groups of kangaroo mice and to evaluate gene flow, demographic trends, and genetic integrity. Results confirm that there are at least three genetically distinct units within M. megacephalus and two such units within M. pallidus. The three units of M. megacephalus appear to have different demographic histories, with effectively no gene flow among them since their divergence. Similarly, the two units of M. pallidus also appear to have experienced different demographic histories, with effectively no gene exchange. Contemporary effective population sizes of all groups within Microdipodops appear to be low (<500), suggesting that each genetic lineage may have difficulty coping with changing environmental pressures and hence may be at risk of extirpation. Results of this study indicate that each Microdipodops group should be recognized, and therefore managed, as a separate unit in an effort to conserve these highly specialized taxa that contribute to the diversity of the Great Basin Desert ecosystem.北美西部的大盆地沙漠（Great Basin Desert）因复杂的生物地理历史与近期人为活动干扰，经历了频繁的生境扰动。近期的生境变化大概率导致了该区域本土动植物种群的衰退。暗袋鼠鼠（Microdipodops megacephalus）与淡色袋鼠鼠（M. pallidus）是大盆地沙漠特有的生态特化物种，亦是评估该脆弱区域生态系统健康状况、推演其生物地理历史的理想模式生物。本研究利用新开发的核编码微卫星位点（nuclear-encoded microsatellite loci），对空间隔离的袋鼠鼠类种群内部及种群间的变异模式展开评估，并分析其基因流、种群动态趋势与遗传完整性。研究结果证实，暗袋鼠鼠（M. megacephalus）内至少存在3个遗传分化显著的演化单元，淡色袋鼠鼠（M. pallidus）内则存在2个此类演化单元。暗袋鼠鼠的3个演化单元具有截然不同的种群历史，自分化以来彼此间几乎不存在有效基因交流；同理，淡色袋鼠鼠的2个演化单元也呈现出差异化的种群历史，且二者间同样无有效基因交换。当前所有魁鼠属（Microdipodops）类群的有效种群规模均较低（<500），这表明每个遗传谱系均难以应对持续变化的环境压力，因此面临局部灭绝的风险。本研究结果表明，应将每个魁鼠属类群视为独立的演化单元进行分类认定与管理，以保护这些高度特化的类群——它们对维持大盆地沙漠生态系统的物种多样性具有重要贡献。