LAUSR

Evolution Adaptation to new environments often occurs in similar ways across different colonization events. Stickleback fish represent a classic example of this, in which repeated colonizations of freshwater have resulted in the loss of pelvic hind fins. Previous work has shown that a pelvic enhancer gene is involved. Xie et al. now show that this gene lies within a region of the genome that is prone to double-stranded DNA breakage owing to a high thymine-guanine content. This enhanced region of breakage could lead to enhanced mutation rates that facilitate repeated adaptations to new environments. Science , this issue p. [81][1] [1]: /lookup/doi/10.1126/science.aan1425