Giblets: Killing and cloning mammoths!

I've loved seeing the back and forth about the destruction of the huge animals in North America 12,900 years ago. In the last few decades the idea of humans causing ecological destruction became popular. While this no doubt has happened at times similar to how Jared Diamond explains in his book Collapse (which I haven't read...) I think the theory immediately got over applied to every kind of ecological collapse.

http://greatplainshistory.blogspot.com/2009/04/megafauna-fires-and-black-blizzards.html

It was applied to the extinction of mega fauna in North America. 12,900 years ago, humans were somewhat new in North America (those dates keep getting pushed back), and around this time, the destruction of thirty plus species of large animals were wiped out. This is where the Mastodon, Mammoth, Sabre Toothed Tiger, different species of lions, camels, dire wolves, sloths, giant beavers, horses, sloths, stag-moose and others died out.

http://rewilding-symposium.weebly.com/

One article claimed that the variety of mega fauna in North America 13,000 years ago was greater than the variety of mega fauna in the wild unpopulated areas of Africa, and probably similar in terms of animal interactions. Pretty sweet.

http://scinewsblog.blogspot.com/2011/11/did-humans-or-climate-change-kill-off.html

So of course these little human Clovis peoples walked around North America and Canada, destroying all the mega fauna. It seems to me that you'd need a lot of people to do all that hunting. Like several million. If you look at the history of Great Britain, you'll see that they didn't kill all the bears on that tiny little island until historic times. How many times bigger is North America than Great Britain? Probably like 75 times bigger.
giant bison

http://dinosaurs.about.com/od/Dinosaurs-by-State/tp/The-Dinosaurs-And-Prehistoric-Animals-Of-New-Mexico.htm

It took the Brits until recently (10th century-ish, no one knows) to wipe out all the bears on that tiny island. There are 11 states in the US that are larger than Great Britain. So these Clovis guys wiped out 36 species of animals that were all human sized or bigger just to eat them?

http://ccsbio.blogspot.com/2012/04/rewilding.html

Similarly, if you think humans wiped out the North American animals, why didn't they wipe out all the African animals? Many animals still roam the African savanna.
brontotherium

http://dinosaurs.about.com/od/Dinosaurs-by-State/tp/The-Dinosaurs-And-Prehistoric-Animals-Of-North-Dakota.htm

Or the 'new' other option is a Comet! As funny as it is to say, I wouldn't be surprised if this were the case. The linked article makes the case. Or at least reports on the research that makes the case.
http://www.sciencedaily.com/releases/2012/09/120918111320.htm

http://philosophers-stone.co.uk/wordpress/2012/06/extraterrestrial-object-crashed-into-earth-13000-years-ago-new-evidence-supports-the-controversial-cosmic-impact-theory/

Anyway, for me, and my disbelieving ways... I just can't believe the "we evil humans killed them all" stuff. Not in this case. Frankly I'm amazed at the professionals that attempted to persuade others that it was the case. Couldn't they have put in the disclaimer "this is what we think based on the evidence that we have, which consists of taking what happened in some other places, and agreeing that it must have happened here as well because we got nothing else."