Define vestigial organs. Write name of some vestigial organs in human body and write the names of those animals in whom same organs are functional.

Explanation

(i) Degenerated or underdeveloped useless organs of organisms are called as vestigial organs.
(ii) Appendix is a vestigial organ in humans, but is fully functional in ruminants.
(iii) Muscles of ear pinna are vestigial in humans but are useful in monkey for movement of ear pinna.