East didn't meet west

Pigs, sheep and water buffalo were domesticated separately in the east and in
the west, genetic analysis has revealed. Daniel Bradley of Trinity College
Dublin came to a similar conclusion about cattle in 1994, after studying their
mitochondrial DNA. Now he has found “striking” differences in the genetic
profiles of other modern animals from different parts of the world. “This
duality runs right through sheep, pigs and water buffalo. There is the same
theme of east and west,” Bradley says.