Charles Darwin took a Bible with him on HMS Beagle and planned to become a clergyman, but he came back a scientist. The young Darwin was mad about beetles and geology, but he was an indifferent student who thought entering the clergy would give him a quiet life in which he could pursue his study of the natural world.

His five year expedition to South America and the Galapagos islands would never have happened if his persuasive relative Josiah Wedgwood had not convinced his father that 22 year old Charles, a recent university graduate with no clear purpose in mind, should accept the job of scientist aboard HMS Beagle. The Beagle's assignment was to produce better maps for British ships.

A test for intelligent design?

Credit: FINNIN/AMNH DENNIS

Darwin kept his theory secret for 21 years

Credit: TRUST HEIRLOOMS DARWIN

Darwin went out carrying a pistol in addition to his Bible, and shared a small cabin with two other men. Both a good self promoter and a careful scientist, he sent back massive, carefully collected specimens …