AP BIOLOGY

Detailed explanation-1: -Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures. Examples of vestigial structures include the human appendix, the pelvic bone of a snake, and the wings of flightless birds.

Detailed explanation-2: -Charles Darwin listed a number of putative human vestigial features, which he termed rudimentary, in The Descent of Man (1871). These included the muscles of the ear; wisdom teeth; the appendix; the tail bone; body hair; and the semilunar fold in the corner of the eye.

Detailed explanation-3: -Like your appendix, vestigial structures are structures that do not have a function today, like whales’ hind legs, goosebumps, dewclaws, and your ear muscles. They did have a function in our ancestors and are a major piece of evidence supporting the theory of evolution, which states that organisms change over time.

Detailed explanation-4: -The existence of vestigial organs can be attributed to changes in the environment and behaviour patterns of the organism in question. As the function of the structure is no longer beneficial for survival, the likelihood that future offspring will inherit the “normal” form of the structure decreases.