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，正经历频发的生境改变，近年的生境变化或已导致本土动植物类群衰退。暗型小更格卢鼠（Microdipodops megacephalus）与苍白型小更格卢鼠（M. pallidus）为大盆地沙漠内的生态特化类群，是评估该脆弱区域生态系统健康水平、推演其生物地理历史的理想研究生物。本研究利用新开发的核编码微卫星位点（nuclear-encoded microsatellite loci），分析了空间隔离的小更格卢鼠类群内部及类群间的遗传变异模式，并评估了基因流、种群动态趋势与遗传完整性。研究结果证实，大头小更格卢鼠至少存在3个遗传分化显著的演化单元，而苍白型小更格卢鼠则存在2个此类单元。这3个大头小更格卢鼠演化单元的种群动态历史存在显著差异，自分化以来彼此间几乎未发生基因流；同理，2个苍白型小更格卢鼠演化单元也具有不同的种群动态历史，且未发生基因交流。小更格卢鼠属（Microdipodops）所有类群的当代有效种群规模均较低（<500），提示每个遗传谱系均难以应对持续变化的环境压力，因此面临局部灭绝风险。本研究结果表明，小更格卢鼠属的各个类群均应被视为独立的保护与管理单元，以保护这些高度特化的类群——它们是大盆地沙漠生态系统多样性的重要组成部分。