Alfred Russel Wallace

Alfred Russel Wallace was born in England on 8 January 1823 and began fieldwork in the Amazon basin before moving to the Malay Archipelago, where he identified the faunal divide still called the Wallace Line - the boundary separating Asian and Australasian animal origins across Indonesia. His 1858 paper on evolution through natural selection was published alongside extracts from Darwin's work, spurring Darwin to abandon his larger manuscript and quickly write the abstract that became On the Origin of Species in 1859. Wallace became the 19th century's leading expert on the geographical distribution of animal species, sometimes called the father of biogeography, and worked on warning coloration, the Wallace effect in speciation, and the idea that natural selection in later human evolution acted chiefly on mental faculties rather than physical form. His 1869 account The Malay Archipelago remains both popular and highly regarded, though his later advocacy of spiritualism and belief in a non-material origin for higher human consciousness strained his standing among scientists. He died 7 November 1913, having also been a social activist, an advocate for socialism, and