I was just reading Guns Germs and Steel, and Jared Diamond made a convincing argument that humans are most likely responsible. Wherever humans go, the large meg

I was just reading Guns Germs and Steel, and Jared Diamond made a convincing argument that humans are most likely responsible. Wherever humans go, the large megafauna seem to die shortly afterwards. Humans are pretty effective hunters, and hunt in different ways than other animals. Animals evolved to defend themselves from wolves, not spears or being chased off cliffs. The reason megafauna didn't die off in Africa is because humans evolved alongside them. As humans gradually became better hunters, the animals had time to adapt. But now that humans have guns, and that's starting to change too. The alternative hypothesis of climate change doesn't really make sense, because there have been many periods of climate change in the past that didn't wipe out all the megafauna.