who studied medicine in Edinburgh followed by theology at Cambridge University, intending a career in the Church. However, his interest in natural history led him to accept an invitation in 1831 to join HMS Beagle as naturalist on a round-the-world voyage. After his return five years later he published works on the geology he had observed. He was also formulating his theory of evolution by means of natural selection, but it was to be 20 years before he published The Origin of Species (1859), prompted by similar views expressed by Alfred Russel Wallace. Among his later works was The Descent of Man (1871). See also darwinism.

http://darwin-online.org.uk/ The complete works of Charles Darwin online