What are homologous structures ? Give an example. Is it necessary that homologous structures always have a common ancestor. Justify your answer.

What are homologous structures ? Give an example. Is it necessary that

1.	What are homologous structures ? Give an example. Is it necessary that homologous structures always have a common ancestor. Justify your answer.
Answer» Solution :Homologous structures in vertebrates are wings in birds and forelimbs of lizard. They are so named as they have same structural DESIGN but different function. Presence of such organs indicate that these ORGANISMS would have had common ancestor. Various organisms EVOLVED from that ancestor as they had different habits and HENCE, these structures evolved to help them perform different functions. For example : Forelimbs of lizard, frog, bird and man have same structure but help lizard in creeping, frog in juinping, bird in flying and man in PICKING things.