What are the main differences between the out-of-Africa model and the multiregional evolution model?

The debate regarding the emergence of Homo sapiens centers on two primary models: the out-of-Africa model and the multiregional evolution model.1

Out-of-Africa Model

Also known as the single-origin or replacement model, this theory posits that H. sapiens evolved solely in Africa approximately 315,000 years ago. According to this view, modern humans subsequently migrated into Eurasia and other regions, replacing indigenous archaic hominin populations with little to no interbreeding. This model is widely supported by molecular genetic data, particularly studies of mitochondrial DNA, which suggest a common descent from a small African population.12

Multiregional Evolution Model

The multiregional model, or regional continuity model, rejects the idea of a unique African origin for modern humans. Instead, it proposes that discrete archaic populations of Homo evolved locally into H. sapiens in Africa, Asia, and Europe. Proponents argue that these populations maintained species unity through periodic interbreeding across wide areas, resulting in modern human diversity through long, quasi-separate evolutionary histories in different regions.12

While evidence of limited interbreeding between H. sapiens and archaic groups like Neanderthals has been identified, the out-of-Africa model remains the most widely accepted explanation for human origins.12