Darwin and Wallace are at the heart of understanding evolution and natural selection. Watch as Hank talks about their wonderful (if not seasick-inducing) trips around the world and how theories of evolution "evolved" through history....

Has access to modern medical care thrown a wrench into the 'survival of the fittest' basis of evolution? New research says no -- we're still evolving.

This lesson will introduce the process of natural selection. It is 3 of 5 in the series titled "Natural Selection."