Geographic distribution of mitochondrial DNA variations among grivet (Cercopithecus aethiops aethiops) populations in Central Ethiopia

Since mitochondrial DNA (mtDNA) are maternally inherited without recombination, geographic distribution of mtDNA in semiterrestrial cercopithecines is considered to be influenced by female philopatry. I examined the effect of sex difference in migration patterns on geographic distribution in a habitat whose environment has changed frequently. I investigated ten groups (n = 77) of grivets (Cercopithecus aethiops aethiops) along a 600-km stretch of the Awash River, Ethiopia. I examined the mtDNA distribution among natural local populations whose nuclear variation was already shown to have a widely homogeneous distribution. RFLP analysis of whole mtDNA genome using 17 enzymes identified ten haplotypes in five clusters (haplogroups). Sequence divergence within haplogroups ranged from 0.17%-0.38%, while divergence between haplogroups ranged between 1.0%-2.5%. Haplogroups were distributed in blocks which ranged from 120-250 km along the Awash River. The haplotype distribution pattern of males indicated that they migrate between the boundaries of these blocks. Moreover, a clumped distribution pattern suggests the history of matrilineal distribution by group fission and geographic expansion.