Vestigial Structures

Vestigial Structures are structures that have lost their original function or seem to have no function at all. (Examples: coccyx, wisdom teeth, appendix, etc.) At one point in time these structures probably had some sort of function, but through the evolution process we may have had no further use for them. Vestigial structures aren't just found in humans they're also found in animals, such as a whale has remnants of a hind leg bones, and pythons have pelvic spurs (Which are thought to be the remnants of legs.) Monkeys have extrinsic ear muscles that allow them to move their ears in all directions. Humans have the same extrinsic ear muscles but for us they have no function. At one time for our ancestors perhaps the ear muscles helped them to locate food or know if an enemy was nearby. With all these vestigial structures, do you ever wonder what their purpose is?

http://evolution.about.com/od/evidence/tp/Vestigial-Structures-In-Humans.htm

Exploring Biology in the Laboratory - page 220 - Murray Paton Pendarvis; John L. Crawley.

http://faculty.uca.edu/johnc/vestigial_struct_c.jpg

http://s3.amazonaws.com/engrade-myfiles/4093608100303480/snake_ancestor.gif