polygenesis

1. (biology) The theory that living organisms originate in cells or embryos of different kinds, instead of coming from a single cell; as opposed to monogenesis.uncountableusually

2. (linguistics) The theory that languages developed independently in different places at different periods, as opposed to originating from a single source.Examples: "The alternative to monogenesis for the origin of language is polygenesis, i.e. that language originated in human evolution at a number of distinct points. If polygenesis is assumed, then the different protolanguages would have developed independently and lead over millennia to the diversity of the descendant languages found at the present day."uncountableusually