Alfred Russel Wallace

Alfred Russel Wallace OM, FRS (8 January 1823 – 7 November 1913) was an British naturalist, explorer, geographer, anthropologist, and biologist.

He did extensive fieldwork, first in the Amazon River basin and then in the Malay Archipelago, where he identified the Wallace Line dividing the fauna of Australia from that of Asia. He is best known for independently proposing a theory of natural selection which prompted Charles Darwin to publish on his own theory. Wallace was also one of the leading evolutionary thinkers of the 19th century who made a number of other contributions to the development of evolutionary theory, including the concept of warning colouration in animals, and the Wallace effect, a hypothesis on how natural selection could contribute to speciation by encouraging the development of barriers against hybridization. He was also considered the 19th century's leading expert on the geographical distribution of animal species and is sometimes called the "father of biogeography".[1]

Wallace was strongly attracted to unconventional ideas. His advocacy of Spiritualism and his belief in a non-material origin for the higher mental faculties of humans strained his relationship with the scientific establishment, especially with other early proponents of evolution. In addition to his scientific work he was a social activist who was critical of what he considered to be an unjust social and economic system in 19th-century Britain. His interest in biogeography resulted in his being one of the first prominent scientists to raise concerns over the environmental impact of human activity.

Source: Wikipedia