Mitochondrial DNA population structure of roan and sable antelope: implications for the translocation and conservation of the species

Mitochondrial DNA (mtDNA) control region sequences were analysed to determi ne the geographical genetic structure of Hippotragus niger (sable antelope) and H. equinus (roan antelope). Analyses by AMOVA, minimum evolution netwo rks, parsimony, neighbour joining and maximum likelihood show that the roan antelope populations are geographically partitioned and that their phyloge ography corresponds well with subspecific boundaries. In sharp contrast, ho wever, our sequence data group all the sable antelope into two well-delinea ted maternal clades. One comprising specimens from the strictly east Africa n H.n. roosevelti, and a second geographically diverse group which includes H.n. niger (South Africa, Zimbabwe), H.n. variani (Angola), and H.n. kirki i (Zambia, Malawi). The differences in the genetic population structure sug gest that distinct extrinsic and intrinsic factors have shaped the phylogeo graphy of these two closely related antelope species. In the absence of obv ious extrinsic barriers to gene flow, we suggest that behavioural differenc es may be responsible, at least in part, for the contrasting spatial patter ns detected among geographical localities. Although our data reflect only t he maternal phylogeny of these important game species, they nonetheless sug gest that different management strategies should be applied. We recommend t hat roan antelope be translocated only within the currently defined subspec ies boundaries, while in the case of sable antelope, conservation measures should focus on preserving the genetic integrity of the east African and so uthern African sable populations. Implicit in this is that translocations o f animals between populations comprising these two distinct maternal geneti c clades should be actively discouraged.