Following human occupation, the house mouse has colonised numerous islands, exposing the species to a wide variety of environments. Such a colonisation process, involving successive founder events and bottlenecks, may either promote random evolution or facilitate adaptation, making the relative importance of adaptive and stochastic processes in insular evolution difficult to assess. Here, we jointly analyse genetic and morphometric variation in the house mice (Mus musculus domesticus) from the Orkney archipelago. Genetic analyses, based on mitochondrial DNA and microsatellites, revealed considerable genetic structure within the archipelago, suggestive of a high degree of isolation and long-lasting stability of the insular populations. Morphometric analyses, based on a quantification of the shape of the first upper molar, revealed considerable differentiation compared to Western European populations, and significant geographic structure in Orkney, largely congruent with the pattern of genetic divergence. Morphological diversification in Orkney followed a Brownian motion model of evolution, suggesting a primary role for random drift over adaptation to local environments. Substantial structuring of human populations in Orkney has recently been demonstrated, mirroring the situation found here in house mice. This synanthropic species may thus constitute a bioproxy of human structure and practices even at a very local scale.

中文翻译：

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奥克尼岛小鼠的遗传结构：隔离促进形态多样化

在人类占领之后，家鼠在许多岛屿上定居，使该物种暴露在各种各样的环境中。这种涉及连续的创始人事件和瓶颈的殖民化过程可能会促进随机进化或促进适应，使得适应性和随机过程在孤立进化中的相对重要性难以评估。在这里，我们共同分析了来自奥克尼群岛的家鼠（Mus musculus domesticus）的遗传和形态变异。基于线粒体 DNA 和微卫星的遗传分析揭示了群岛内相当大的遗传结构，表明岛屿种群的高度隔离和长期稳定性。基于第一上磨牙形状量化的形态测量分析，揭示了与西欧人群相比相当大的差异，以及奥克尼群岛的显着地理结构，这在很大程度上与遗传差异的模式一致。奥克尼的形态多样化遵循布朗运动进化模型，表明随机漂移在适应当地环境方面的主要作用。最近，奥克尼的人口结构得到了证实，这反映了在家鼠身上发现的情况。因此，即使在非常局部的范围内，这种共人类物种也可能构成人类结构和实践的生物代理。表明随机漂移在适应当地环境方面的主要作用。最近，奥克尼的人口结构得到了证实，这反映了在家鼠身上发现的情况。因此，即使在非常局部的范围内，这种共人类物种也可能构成人类结构和实践的生物代理。表明随机漂移在适应当地环境方面的主要作用。最近，奥克尼的人口结构得到了证实，这反映了在家鼠身上发现的情况。因此，即使在非常局部的范围内，这种共人类物种也可能构成人类结构和实践的生物代理。