By examining fossils and by determining their relative and absolute ages, scientists have collected evidence that supports the theory that species changed over time.
Further evidence is derived from living organisms.
In order to determine if species change scientists compare common ancestry, structure, biochemistry, and development of organisms alive today. As you read this section, study this evidence and critically evaluate whether it indicates that species may have arisen by descent and modification from ancestral species. If species change over time, then scientists should be able to cite examples showing that a group of living species may have come from a common ancestor. Let us examine one of many cases for which this seems to be true. Gracing the islands of Hawaii is a family of birds commonly called the Hawaiian honeycreepers.