He blames it all on human hunting which makes more sense to me than pathogens when you consider it wasn't just mammoths that were made extinct but also many other large mammals. I should note here that Ward claims that hunting was THE reason for the extinction of large mammals and that climate change had only a secondary role if any. He has some pretty good proofs for this theory too.
What I like about the Ward theory is that it flies in the face of all the liberal excuse makers for native hunting. The liberal theory is that native hunters were and are "natural conservationists" and lived in harmony with the nature. It was only when the evil European came along that things got out of balance.
Of course this is bull but I have heard it everywhere I have lived or traveled, even in Africa. Because natives didn't have the means to drive every animal to extinction does not mean they are or were natural conservationists. When given the means they killed everything they could. The Ice Age mammals are a case in point. There are others too. Elk in Eastern Washington state were most likely all extirpated in pre-Columbian times by native hunters. There are many more examples, some a lot more recent.
These people seem to forget that we were all at one time "native hunters". The distance in time that separates us from what they like to call native hunters is nothing in evolution terms. All humans are the same. They killed everything they could with little thought of tomorrow. It wasn't until very recently we learned the value of conservation. It wasn't a native value, not matter what the skin color of the 'natives'. It was something learned through a culmination of knowledge that was passed on through mostly European derived cultures and didn't really even begin to be recognized until the 18th century and then only in the most educated, enlighten spheres. It wasn't until the late 19th and early 20th century that conservation became recognized more or less universally and mostly through the efforts of those evil people of European decent.