A five year voyage of exploration around the world. This trip began when Darwin was 22 years old and just graduated from Cambridge with a degree in theology. He sailed as a naturalist on the British Navy's H.M.S. Beagle mapping expedition (1831-1836). His observations on this voyage led him to accept that evolution occurs. Especially important to the development of this understanding was his visit to the Galápagos Islands in the Eastern Pacific Ocean. It was there that he began to understand what causes plants and animals to evolve.