Honors Biology (HBio) Evolution Practice Exam

Analogous traits come from convergent evolution: different species facing similar environmental challenges evolve features that look alike and serve similar functions, but these traits do not come from a recent common ancestor. The statement that fits this idea is that the trait arises independently in separate lineages due to similar selective pressures. For example, wings used for flight in insects and in birds evolved separately from different starting structures, yet both enable flight. By contrast, traits that are inherited from a common ancestor and kept across descendants are homologous, such as the same basic forelimb bone pattern found in humans, cats, whales, and bats. So the best description of an analogous trait is independent origin in response to similar selective pressures.