You are ignorant of the history of that time. Social pressure did not killed off Buffalo. U.S. government  had a hand in that to starve the plains Indians out and force them to take white man's charity on government reservations. So white settlers could reach gold ares and start settlements. Remember white Buffalo hunters killing thousands for hides and left meat to rot? You remember Jefferson's "manifest destiny" crap?  I call it land grabbing idiots for greed and some moronic legacy of east coast railroad barons and oil mogels. Imminent domain still reins. Keystone Pipeline is now taking away land that whites took from Indians. Perfect karma.