Question

What structure has become useless through evolution but still exists,

typically in a much reduced form?

Answer 1

A "vestigial structure" or "vestigial organ" is an anatomical feature or behavior that no longer seems to have a purpose in the current form of an organism of the given species. Often, these vestigial structures were organs that performed some important functions in the organism at one point in the past.

Step-by-step explanation: