Alfred Russel Wallace (1823 – 1913) was an English Naturalist, best remembered for being the co-discoverer of the theory of evolution by natural selection.
Wallace derived the core ideas of the theory independently of Darwin, not knowing Darwin had already developed the idea in much more depth.) Wallace, who was doing field work abroad, sent an account of his thinking to Darwin, who recognised the overlap with his own theory. Darwin arranged to have Wallace's acount read at the same scientific meeting as a précis of his own theory, ahead of the publication of his book length ccount (i.e., The Origin of Species) rather than taking advantage of Wallace's absence by publishing ahead of him.
Unlike Darwin, who had family money to support his work and could focus on his research, Wallace had to earn his living by selling specimens he collected or writing popular accounts of his work. Wallace undertook extensive fieldwork in South America (but unfortunately much of his collection from there was lost in a shipwreck when being sent back to Britain) and in the Malay Archipelago – the many islands between Asia and Australia.
Wallace had to stop collecting when ill with fever, and it was during this break that he recorded his ideas on evolution that he sent to Darwin (whom he considered the only person likely to take them seriously).
Wallace recognised a distinct, and quite abrupt, shift in the pattern of fauna as one moved though this Archipelago – a kind of boundary that did not correspond to where the largest distances were betwen island groups. This is now known as the Wallace line and considered important evidence that the geography of the region had changed since the types of animals present had arrived there.
Darwin lobbied the govenment to have Wallace's contributions recognised by the award of an annual pension which gave him financial security at the end of his life. Besides his scientfiic work, Wallace was also active in social reform causes and the spiritualist movemement.
