In this edition of "The Story of Man and His World," Free explained why evolution is a credible theory. Since fossils demonstrate how Earth's species have changed over the years, there's no reason to believe that they sporadically appeared fully-formed via supernatural events. Second, the human body contains several leftover relics from primitive ancestors, such as the tailbone and the appendix. Neither of these structures serve a real purpose to us today. You can also see how parts of the human body, like our fingernails and our spines, were inherited by animals that came before us. If you experience difficulty imagining how human beings evolved from worm and fish-like creatures, consider how a human fetus develops from a tadpole-shaped creature to a baby within nine months. Finally, Free pointed out, artificial breeding shows how evolution works on a smaller scale.
Read the full story in "The Proofs of Evolution"