Star Nemesis Giraffe

Are bison Bison?

The two living species of wild cattle generally known as "bison" - American bison Bos bison and European bison or wisent Bos bonasus - have traditionally been in a genus of their own, the eponymous Bison, separate from other close relatives of domestic cattle. Genetic research, however, shows that the two bison are actually within the "true" cattle genus Bos, closely allied to the yaks Bos mutus and Bos grunniens. Keeping them separated in their own genus Bison would render Bos paraphyletic - that is, a lineage that is based around common ancestry but does not include all of that ancestor's descendants. The alternatives would be to split the genus Bos into several more-restricted genera (Poephagus for the yaks and Bibos for the South and Southeast Asian wild cattle) to keep the bison Bison, which is not ideal given the obvious close affinity that these cattle share; or, to lump the bison back into Bos. As should be obvious, the latter is the course followed here, as well as by the American Society of Mammalogists.

Ref:

American Society of Mammalogists. Bos bonasus Linnaeus, 1758. ASM Mammal Diversity Database.

Grange, T, J-P Brugal, L Flori, M Gautier, A Uzunidis, and E-M Geigl. 2018. The evolution and population diversity of bison in Pleistocene and Holocene Eurasia: Sex matters. Diversity 10(3):65.