Scientists conducted a replicated, globally synchronized evolution experiment with the plant Arabidopsis thaliana lasting 5 years in over 30 outdoor experimental gardens in various climates in Europe, the Levant, and North America.[6][1] In each of 360 small plots, they planted a genetically diverse population of several hundred plants native to the temperate zone.[1][6] They observed rapid and repeatable adaptation across climates, with allele frequency changes being parallel in replicates in the same climates but different in contrasting climates.[6] Some changes in allele frequency are explained by strong selection pressure ranging from -46% to +60%.[6] Genomic analysis revealed a polygenic architecture of adaptation with both known and novel variants associated with environmental stress response, CAM5 and HEAT SHOCK FACTORs, timing of germination and spring flowering (CYTOCHROME P450s and TSF).[6] In warm climates, populations with predictable evolutionary changes survived up to 5 years, while those with chaotic genetic changes died out, especially in the hottest and driest locations, after 3 years.[1][5][6] These findings show that rapid climate adaptation is possible, but its limits depend on the environment and genetic diversity.[6][5]