 A strong and clear defense of monogenesis was provided by Immanuel Kant (1724–1804) in his essay “Of the Different Human Races,” first published in 1775 and revised in 1777. Kant argued that all humans descend from a common human “lineal root genus” in Europe, which contained the biological “seeds” and “dispositions” that can generate the distinct physical traits of race when triggered by divergent environmental factors, especially combinations of heat and humidity. This, combined with patterns of migration, geographic isolation, and in-breeding, led to the differentiation of four distinct, pure races: the “noble blond” of northern Europe; the “copper red” of America (and east Asia); the “black” of Senegambia in Africa; and the “olive-yellow” of Asian-India. Once these discrete racial groups were developed over many generations, further climatic changes will not alter racial phenotypes (Bernasconi and Lott 2000, 8–22).