In 1831 a British science expedition set sail. For the next five years Charles Darwin served as naturalist aboard the H.M.S. Beagle.
Studying fossils in South America, Darwin noticed a similarity between certain extinct animals and modern species. The expedition ventured worldwide and Darwin studied plants and animals, collecting specimens along the way.
The Galapagos Islands became a keen interest for him as he recorded the variations of plants and animals like what he had seen in South America. From these observations Darwin would later develop his theories of evolution.