It always seemed kind of shocking to me that you could cross-breed cattle and bison. However, according to Wikipedia[1]: The bovine family (Bovidae) diverged

It always seemed kind of shocking to me that you could cross-breed cattle and bison. However, according to Wikipedia[1]: The bovine family (Bovidae) diverged from the common ancestral line with water buffalo and African buffalo about 5 to 10 million years ago. Thereafter, the family lineage of bison and taurine cattle does not appear to be a straightforward "tree" structure as is often depicted in much evolution, because evidence of interbreeding and crossbreeding is seen between different species and members within this family, even many millions of years after their ancestors separated into different species. So it sounds like they've been colliding all along. [1]https://en.wikipedia.org/wiki/Bison#Evolution_and_genetic_history https://en.wikipedia.org/wiki/Bison#Evolution_and_genetic_hi...