For example, you may come across information during your research about homology. Homology is a similarity of structural features between organisms, even though the structures may serve different purposes for each organism. It is evidence for evolution because there is no overriding mechanical or biological reason for them to be so similar structurally; therefore, they likely developed from a common ancestor. One example is the similarity between the human arm, cat forelimb, whale front flipper, and bat wing.

After conducting your research, select one argument that is used to support the theory of evolution and create a discussion board entry to explain the argument and to describe whether or not you think the argument is valid and why or why not you think so.