Which ship did Charles Darwin sail on to the Galapagos?

HMS Beagle, and Darwin was not the naturalist - he was, in effect, a gentleman companion for the captain. Robert FitzRoy wanted an educated dining companion of his own class to talk to across a long voyage, because naval discipline forbade fraternising with his officers and the previous captain of the Beagle had shot himself.

The voyage was meant to last two years and took nearly five, and Darwin was seasick for most of it. He also did not have his revelation on the Galapagos: he failed to label which island his finches came from, had to reconstruct it afterwards from other people's specimens, and the birds were identified as distinct species by the ornithologist John Gould in London after he got home. The islands mattered enormously in retrospect and much less at the time.

FitzRoy's own story is the sad one. He was a devout literalist who came to be appalled at his part in the theory, reportedly stood at a public debate holding a Bible above his head, and later founded the Meteorological Office and invented the weather forecast - for which he was mocked in Parliament and in the press. He killed himself in 1865.