Final answer:
The Multiregionalism Model of human evolution posits that gene flow through interbreeding among different populations of Homo sapiens prevented them from becoming separate species by maintaining genetic connectivity.
Step-by-step explanation:
According to the Multiregionalism Model, gene flow prevented local populations of pre-modern Homo sapiens from becoming separate species. Gene flow refers to the transfer of genetic variation from one population to another, which would have occurred through interbreeding among different populations of early humans. This model suggests that continuous gene flow between geographically separated populations contributed to a single, interconnected species with regional variations.
The Multiregionalism Model is contrasted by the Out of Africa model, which suggests that modern humans first emerged in Africa and then spread across the globe, replacing other human species. The diversity observed in modern humans according to the Multiregionalism Model is attributed to local adaptations to diverse environments and the persistence of gene flow between geographically dispersed groups.