The Biological Species Concept and Human Evolution.
Paul R Ehrlich wrote his paper, 'Has the Biological Species Concept Outlived Its Usefulness' in December 1961, publishing it in the pages of Systematic Zoology , 10(4):167-176 (DOI: 10.2307/241164). The concept was supposedly decisively refuted by Sokal and Crovello in 1970 (Sokal, R.R. & Crovello, T.J., 'The Biological Species Concept: A Critical Evaluation,' The American Naturalist , 104(936):127-153 , March-April 1970). The biological species concept (hereinafter BSC) was developed by the Russo-American geneticist, Theodosius Grigorievich Dobzhansky (1900-75) in 1935 ('A Critique of the Species Concept in Biology,' Philosophy of Science , 2(3):344-355 , DOI: 10.1086/286379) and developed by the German biologist Ernst Mayr (1904-2005) in (e.g.) his Systematics and Origin of Species , New York, NY: Columbia University Press, 1942, and defended in Chapter 2, ' The biological species concept ', of Species Concepts and Phylogenetic Theory: A Debate ,