Relationships of the takin (Budorcas taxicolor) and muskox (Ovibos moschatus) have been speculated upon for many years. Morphological and behavioral similarities between these species have led to suggestions that they are closely related. To test the hypothesis that characteristics shared by the takin and muskox stem from a recent common ancestor, we compared sequences of their mitochondrial cytochrome b genes with those of three other species of Caprinae. We present data that may support rejection of the hypothesis of recent common ancestry and suggest that similarities in behavior and morphology in these two species might be attributed to convergent evolution rather than shared phylogeny.