the horse and EU/UK demand for meat and hides
Native Americans had been hunting bison as their primary game animal since about 10,000 years ago when 34 other large mammal species went extinct at the end of the Pleistocene. Although their subsistence patterns diversified into gardening and the gathering of various plant resources, bison still played a large part in the diet of native Americans when Europeans discovered the Americas in 1462, especially in the plains. What was it, then, that caused such a drastic change in native American behavior and led to large scale hunting of the North American bison? The prevailing theory is that it was the re-introduction of the horse into North America that was the key to the role of the native American in the decline of bison populations.