| 要旨 |
Considering current rapidly changing environments, understanding evolutionary population dynamics is required for prediction of population fates in changing environments. Long-term population dynamics and spatial and temporal distributions across environments depend on a balance among selection, gene flow and genetic drift. Adaptation to local environments for peripheral populations may be limited by gene flow from the central populations. Limited gene flow could lead to rapid local adaptation at peripheral.
Picea sitchensis has rapidly extended or shifted its range along with the Holocene postglaciation. This species may reveal the relationship between gene flow and adaptation and of the historical dynamics. The degrees of adaptation of populations in similar climates but with different levels of gene flow is studied to determine the degree to which gene flow limits adaptation, and thus range expansion. Our objective is to understand the roles of gene flow in the adaptation and evolution of species’ range, using P. sitchensis as a model species. Specific interests are 1) the tradeoff between gene flow and adaptation, 2) the historical dynamics and the range expansion during the last deglaciation. We approach these issues using analyses of both genetic markers and quantitative traits for the assessment of gene flow and adaptation, respectively.
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