Natural selection drives emergent genetic homogeneity in a century-scale experiment with barley

• 成果类型: Article
• 署名作者: Landis, Jacob B.; Guercio, Angelica M.; Brown, Keely E.; Fiscus, Christopher J.; Morrell, Peter L.; Koenig, Daniel
• 署名单位: University of California System; University of California Riverside; University of California System; University of California Riverside; University of Minnesota System; University of Minnesota Twin Cities
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10770
• DOI: 10.1126/science.adl0038
• 发表日期: 2024-07-12
• 关键词: bulk-hybrid population; flowering time; sequence; domestication; arabidopsis; EVOLUTION; rice; adaptation; distance; protein

摘要

Direct observation is central to our understanding of adaptation, but evolution is rarely documented in a large, multicellular organism for more than a few generations. In this study, we observed evolution across a century-scale competition experiment, barley composite cross II (CCII). CCII was founded in 1929 in Davis, California, with thousands of genotypes, but we found that natural selection has massively reduced genetic diversity, leading to a single lineage constituting most of the population by generation 50. Selection favored alleles originating from climates similar to that of Davis and targeted loci contributing to reproductive development, including the barley diversification loci Vrs1, HvCEN, Ppd-H1, and Vrn-H2. Our findings point to selection as the predominant force shaping genomic variation in one of the world's oldest biological experiments.