Alfred Russel Wallace
(1823—1913) naturalist, evolutionary theorist, and social critic
British naturalist, who in 1848 went on an expedition to the Amazon, and in 1854 travelled to the Malay Archipelago. There he noticed the differences between the animals of Asia and Australasia and devised Wallace's line, which separates them. This led him to develop a theory of evolution through natural selection, which coincided with the views of Charles Darwin; their theories were presented jointly to the Linnaean Society in 1858.