HMS Beagle. Engraving of HMS Beagle, the ship that carried Charles Darwin during the voyage that inspired his theory of evolution. Darwin (1809- 82) joined the crew of the Beagle on 27 December 1831 as an unpaid naturalist for a five-year voyage. Despite being only 30 m long and weighing 235 tonnes, the vessel circumnavigated the world. The expedition mainly studied the South American coast, collecting hydrological, geological and meteorological data. From his observations Darwin noted that some fossils closely resembled organisms which still lived in the same area. He also noted the links between distinct but similar species in different areas.