As human beings continue to disturb their environments, they impact not only the distribution of plant and animal species, but also the distribution of individuals (and thus their genomes) within these species. Many "weedy" species can frequently be moved long distances intentionally or unintentionally by humans, and it is important to understand the extent to which human activity can shuffle the gene pool of a given species. Earlier studies have shown that genomes in the plant model organism thale cress (Arabidopsis thaliana) may be geographically shuffled in Europe, an area experiencing relatively high levels of human activity, but geographically structured in central Asia, with relatively low levels of human activity. This study will identify different Arabidopsis thaliana genomes by typing genetic variation, and will examine the geographic location of these genomes in order to understand both natural and human impacts on its gene pool. Natural impacts include the contraction and expansion of Arabidopsis thaliana's range during the advance and retreat of Pleistocene glaciers; human impacts include the human caused movement described above.
Broader impacts of this study will include highlighting the extent to which human activities can affect other species, a critical issue as we continue to profoundly alter environments. This study will also enhance Arabidopsis thaliana as a model organism by identifying geographic areas in which its gene pool has been minimally impacted by humans, and providing seed from these areas to the global research community.
