Discussion Questions: Evolution of the Eye

In order to support the hypothesis that a complex eye could have evolved through intermediate stages, one must demonstrate that those intermediate stages each offered some selective advantage over their predecessors. Discuss how work shown in this video clip demonstrates this series of intermediate advantages in eye evolution.

Mentioning the eyes of flatworms and chambered nautilus as examples of "intermediate" stages in eye evolution does NOT imply that the human eye evolved from the precise kind of eyes now found in those living forms. Discuss why, then, these examples are mentioned in the video.