Tables from: "Natural selection on the Arabidopsis thaliana genome in present and future climates"
Through the lens of evolution, climate change is an agent of natural selection that forces populations to change and adapt, or face extinction. Current assessments of the risks associated with climate change, however, do not typically take into account that natural selection can dramatically impact the genetic makeup of populations. We made use of extensive genome information in Arabidopsis thaliana and measured how rainfall-manipulation affected the fitness of 517 natural lines grown in Spain and Germany. This allowed us to directly infer selection at the genetic level. Natural selection was particularly strong in the hot-dry Spanish location, killing 63% of lines and significantly changing the frequency of ~5% of all genome-wide variants. A significant proportion of this selection over variants could be predicted from the climate (mis)match between experimental sites and the geographic areas where variants are found (R2=29-52%). Field-validated predictions across the species range indicated that Mediterranean and Western Siberia populations — at the edges of the species' environmental limits — currently experience the strongest climate-driven selection, and Central Europeans the weakest. With rapidly increasing droughts and rising temperatures in Europe, we forecast a wave of directional selection moving North, putting many native A. thaliana populations at evolutionary risk.