British naturalist who developed a theory of evolution by means of natural selection at the same time as Charles Darwin. Wallace, who did most of his work with insects in the Amazon and the Malay Archipelago, concluded that bio¬ logical evolution must be governed by a mechanism that closely resembled the theory proposed by the economist Thomas Robert Malthus (1766-1834): Variations that helped a species to survive would be perpetuated in future generations. Wallace published a book on the subject, On the Law Which Has Regulated the Introduction of New Species (1855).
Wallace soon came into contact with Darwin through a mutual friend. Realizing that Darwin’s work predated his own, Wallace agreed to combine his work with that of the older man, and they presented their ideas together in July 1858. Wallace continued to present his ideas in books such as Malay Archipelago (1869), Contributions to the Theory of Natural Selection (1870), and Island Life (1880). Later in life, he took a strong stand as an antiracist, declaring that all people, regardless of race, had similar inherent intellectual capacities.