Charles Darwin. Engraving of Charles Robert Darwin (1809-1882), British naturalist. As a young man Darwin briefly studied medicine then trained in the clergy, but his interest was in natural history. In 1831 he set sail as naturalist on HMS Beagle, which was to provide the fieldwork for his famous book: Origin of Species (1859). His theory of natural selection suggested that natural variation in a species creates a wide range of individual traits, some more useful than others. Competition to survive provides a driving force for evolution in the form of natural selection. His theory fuelled bitter controversy. Portrait engraved in 1871.