Heterozygosity drops and linkage disequilibrium rises with distance from Africa. Serial founder model explains these genome-wide patterns in human populations. Archaic introgression loci appear in Homo sapiens genomes. Serial founder model assumes no archaic admixture but remains valid with it. Genetic differentiation forms intercontinental clusters and intracontinental clines. Non-African populations carry reduced genetic variation from founder bottlenecks. Serial founder serves as null model to detect archaic admixture signatures. Archaic admixture compatible with out-of-Africa expansion patterns. Worldwide populations cluster genetically by continent.