I've read the book. And afterwards I felt very compelled to believe what he had to say, but overtime, more and more examples start pointing to an over simplific

I've read the book. And afterwards I felt very compelled to believe what he had to say, but overtime, more and more examples start pointing to an over simplification of what is possible. Horses may have herd dominance, but what about the ox? or the donkey? or the water buffalo? or the yak?