Question

Darwin observed a variety of beaks in small black birds inhabiting Galapagos Island. Explain what conclusions did he draw and how.

Answer 1

Darwin's finches are a classic example of adaptive radiation. Their common ancestor arrived on the Galapagos about two million years ago. During the time that has passed, Darwin's finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behaviour. Changes in the size and form of the beak have enabled different species to utilize different food resources such as insects, seeds, nectar from cactus flowers as well as blood from iguanas.

This variation helped Darwin arrive at his understanding that the finches and other birds had adapted to the islands and specific environments where they live, leading to the theory that species are not fixed and unchanging; instead, they evolve over time from common ancestors.