Similar forms often evolve repeatedly in nature, raising long-standing questions about the underlying mechanisms. Here, we use repeated evolution in stickleback to identify a large set of genomic loci that change recurrently during colonization of freshwater habitats by marine fish. The same loci used repeatedly in extant populations also show rapid allele frequency changes when new freshwater populations are experimentally established from marine ancestors. Marked genotypic and phenotypic changes arise within 5 years, facilitated by standing genetic variation and linkage between adaptive regions. Both the speed and location of changes can be predicted using empirical observations of recurrence in natural populations or fundamental genomic features like allelic age, recombination rates, density of divergent loci, and overlap with mapped traits. A composite model trained on these stickleback features can also predict the location of key evolutionary loci in Darwin’s finches, suggesting that similar features are important for evolution across diverse taxa.

类似的形式在自然界中经常反复演变，引发了有关潜在机制的长期问题。在这里，我们在刺鱼中使用重复进化来确定大量基因组位点，这些位点在海水鱼类定居淡水栖息地期间反复发生变化。当从海洋祖先实验建立新的淡水种群时，在现存种群中重复使用的相同位点也显示出快速的等位基因频率变化。显着的基因型和表型变化在 5 年内出现，这得益于常设的遗传变异和适应性区域之间的联系。变化的速度和位置都可以使用自然种群中复发的经验观察或基本基因组特征（如等位基因年龄、重组率、不同位点的密度以及与映射特征的重​​叠）来预测。