Medium Ground Finch
The medium ground finch of Daphne Major in the Galápagos Islands became famous through Peter and Rosemary Grant's long-term study documenting evolution in action.
The medium ground finch of Daphne Major in the Galápagos Islands became famous through Peter and Rosemary Grant's long-term study documenting evolution in action. During the 1977 drought, 85% of the population died - not because they were poorly adapted, but because random chance determined which individuals survived.
The drought killed plants that produced small seeds, leaving only large, hard seeds requiring strong beaks to crack. Birds with slightly larger beaks survived not because of superior genetics, but because random developmental variation gave them the right tool at the right time. When the population rebounded, average beak size had shifted significantly through both selection and random sampling of survivors.
Notable Traits of Medium Ground Finch
- Beak size varies in response to food availability
- Subject of longest-running field study of evolution
- Demonstrated natural selection and drift operating on observable timescales