Pupfish

Pupfish

Jawing away: Bahama pupfish study identifies candidate genes driving food-niches

Scientists have studied three closely related pupfish species peacefully co-existing because each, through subtle jaw size differences, has rapidly carved out its own food niche within the last 10,000 years. They have matched DNA changes with differences in jaw size to uncover candidate genes responsible, along with evidence supporting the role of large-effect alleles in crossing larger fitness valleys. More large-effect alleles were required to evolve large jaws than small jaws. Ref. Source 9m.