Jimmy Doherty in Darwin's garden. Part 1, Dangerous ideas.

Presenter Jimmy Doherty recreates Charles Darwin's experiments used to prove his theory of evolution. Doherty visits Down House where Darwin lived, shows Darwin's sketch of the tree of life and gives a brief history of the development of his theory. The first experiment involves soaking seeds in salt water for a month to prove that seeds are able to cross oceans safely. He also looks at artificial selection by talking to pigeon fanciers. Other experiments involve digging up a patch of turf in Darwin's garden to see what happens, counting different types of grasses in a meadow, and an examination of a chalk cliff to determine the age of the Earth.