Question

In what way are homologous organs evidence for evolution?

Answer 1

Homologous organs are those organs which have same basic structure, but perform different functions. For example, the forelimbs of humans, cheetahs, whales and bats have the same basic structure. But humans use forelimbs for grasping, cheetahs for running, whales for swimming and bats for flying. The presence of homologous organs indicate that all these forelimbs have evolved from a common ancestral animal which had a 'basic design' of limb.