The port continued in use, and the young naturalist Charles Darwin arrived with the "Beagle" survey expedition under captain Robert FitzRoy in January 1834. While HMS "Beagle" carried out its hydrographic survey, Darwin explored the local geology in cliffs near the harbour and found fossils of pieces of spine and a hind leg of "some large animal, I fancy a Mastodon". On their return to England, the anatomist Richard Owen revealed that the bones were actually from a gigantic creature resembling the Llama and the camel, which Owen named "Macrauchenia". This was one of the discoveries leading to the inception of Darwin's theory.