mtDNA haplotype network and map.
(A) Median-joining haplotype network of mtDNA HVRI locus generated using Network 4.5. Each cluster is color coded to display the inferred geographic origin of individuals; (i) purple representing western Cameroon and eastern Nigeria (north of the Sanaga River and west of the Mbam River), (ii) green representing central Cameroon (north of the Sanaga and east of the Mbam), and (iii) orange representing southern Cameroon (south of the Sanaga). Haplotypes cluster into two main groups (1 and 2), and 4 sub-groups (1A, 1B, 2A and 2B). (B) Pie charts show the frequency distribution of mtDNA haplogroups (1A, 1B, 2A and 2B) across the study area.