Introduction to the Biometry-Saltationism Debate

The Mendelian rediscoveryMendelian rediscovery at first only increased the discord between the biometric (represented mainly by WeldonWeldon, Walter Frank Raphael and Pearson) and saltationist (represented mainly by BatesonBateson, William) viewpoints on evolution. The biometriciansbiometrician held that evolution occurred continuously, with natural selectionselectionnatural acting on individual differencesindividual differences (as DarwinDarwin, Charles Robert had postulated). On the other hand, the saltationists held that evolution occurred discontinuously by the action of mutationsmutation. To the biometriciansbiometrician, heredity could be understood through Galton’sGalton, Francis ancestral law.ancestral law The saltationists disagreed and insisted that heredity was explained though Mendel’sMendel, Gregor Johann laws.