Domestic cattle: domesticated from what?

[Sattua]

From what kind of animal are today’s domestic cattle–by which I mean standard farm cows and bulls–descended? Are all varieties (Holstein, Black Angus…) the same species? Are the standard cattle in Africa the same species? In Asia? Are cattle in Africa descended from a different animal than cattle in Asia? Which of the two are European cattle–or are they something else again?

[caveman]

From Wikipedia

Cattle were originally identified by Carolus Linnaeus as three separate species. These were Bos taurus, the European cattle, including similar types from Africa and Asia; Bos indicus, the zebu; and the extinct Bos primigenius, the aurochs. The aurochs is ancestral to both zebu and European cattle. More recently these three have increasingly been grouped as one species, sometimes using the names Bos primigenius taurus, Bos primigenius indicus and Bos primigenius primigenius. Complicating the matter is the ability of cattle to interbreed with other closely related species. Hybrid individuals and even breeds exist, not only between European cattle and zebu but also with yaks, banteng, gaur, and bison, a cross-genera hybrid.

[bibliophage]

Straight Dope Staff Report by SDSTAFF Colibri on What did cows evolve from?