Most interesting paper for which the results are long overdue and sadly too late - given the plight of yet another large mammal.

The case of the distinctiveness of C. cottoni having been overlooked is not an isolated one. Another is the antelope Roberts' Lechwe, Kobus robertsi, dismissed as a "Red lechwe". There are likely other such victims of the persistence of typological taxonomy in mammalogy. The case of the "overlooked" southwest African desert warthog is yet another notorious example.

There are sound arguments that the Phylogenetic Species Concept (PSC) is the operational surrogate of Simpson's ESC (Evolutionary Species Concept). Indeed, a large literature has debated these issues. Ultimately, it is a matter of how one employs real data, from extant populations (museum specimens permitting) to evaluate the evolutionary histories of lineages.

The crux of the science at stake here is that these species exhibit independent evolutionary histories; in the case of C. cottoni and C. simum these lineages have been on distinct trajectories for much of the Pleistocene. Too bad that too much impetus is placed on whether such organisms "look similar".

you can download papers on lechwe taxonomy and species concepts etc from my website:
https://sites.google.com/...