Bos primigenius or Bos taurus?

There is some confusion about which name is the proper scientific name for the aurochs, Bos primigenius or Bos taurus. In this post, I am going to investigate the question which of those names is the legitimate scientific name for the aurochs. 

If one considers domestic cattle and aurochs different species because the former has been domesticated, the case is clear which scientific names they should have: the aurochs would be Bos primigenius, described by Bojanus in 1827, and domestic taurine cattle would be Bos taurus, described by Linnaeus in 1758. But there is no scientific consensus on whether domestic animals and their wildtypes should be regarded as one species or separate species. I tend to not regard domestic animals as taxa that need a proper scientific name at all (go here for my post on that). 

So, if aurochs and domestic cattle would be one species, with the aurochs being the wildtype and domestic cattle man-made modified versions of the aurochs created by artificial selection, what is the proper scientific name for that species? This is now where it becomes tricky. 

Due to the rule of priority of the ICZN, the first name used to describe a species has priority. In this case, Bos taurus would be the proper scientific name of the species containing aurochs and domestic cattle because it is the earlier name. However, in 2003 the ICZN decided that 17 names of wildtypes that are pre-dated by names for domestic forms should be conserved, including Bos primigenius (opinion 2027). However, to complicate the issue, Linnaeus actually referred to the aurochs in his description of Bos taurus from 1758. He mentioned the aurochs as “ferus urus” (= “wild aurochs”) living in Poland. Apparently, he was not aware of the fact that the aurochs probably already had died out when he described the species (go here for the youngest aurochs remains currently known). This is taxonomically not relevant however, Linnaeus definitely described the aurochs and domestic cattle as one species in 1758. 

Referring to the aurochs as Bos taurus is therefore definitely legitimate. However, I prefer to follow opinion 2027, also because Bos primigenius at least has a holotype (the Haßleben specimen), while Bos taurus does not. Therefore, it is up to ones’ preference whether to use Bos primigenius or Bos taurus for the species that contains the aurochs, and also depending on your opinion on the taxonomic status of domestic animals in general.