After a severe draught in the Galapagos islands Darwin

Last updated: 6/22/2023

After a severe draught in the Galapagos islands Darwin observed a change in Daphne beaks depth Which statement about the beak size of finches on the island of Daphne Major during prolonged drought is true Mean bank depth Percentag In each dans 12 9 10 Beak All Daphne hirde 1975 11 depth mm Total number of birds 753 12 13 14 Drought in 1977 12 Mean beak depth 1879 Survivors Total number of birds 00 9 10 Beak depth mm 11 12 13 Each bird evolved a deeper stronger beak as the drought persisted Each bird s survival was strongly influenced by the depth and strength of its beak as the drought persisted The frequency of the strong beak alleles increased in each bird as the drought persisted Each bird that survived the drought produced only offspring with deeper stronger beaks than seen in the previous generation