Schleicher was an advocate of the polygenesis of languages. The British atheist leader Charles Bradlaugh was also interested in the theory of polygenesis. According to Morton's theory of polygenesis, races have been separate since the start. Many oral traditions feature polygenesis in their creation stories. Genesis of subtropical soils with stony horizons in NE Argentina&colon; Autochthony and polygenesis. Polygenesis is not to be confused with the wave theory, originally propounded by Johannes Schmidt.