The same thing happened around 1000 years ago when we reached New Zealand and Madagascar.
Most of the damage of the Anthropocene may already have been done.
Unless global warming gets sufficiently bad, in which case that will be the worst damage.
Maybe, but the opposite situation is also possible. You can wipe the preys if you remove the predadors. We had see this in New Zealand for example where Tasman devil has protected decens of species of smaller marsupials, extinct in the continent but not here. This is the same big scale experiment that we are playing currently in Africa. In one or other case the result is the same, almost all european big mammal fauna vanished; and a replace is still missing for the equivalent of european elephant, european rhinos or north american cheetah.
https://en.wikipedia.org/wiki/Quaternary_extinction_event#Hu...
North America and Europe underwent dramatic climate change as several hundred feet tall ice sheets covering large parts of the land mass melted and temperatures rose suddenly which would explain why megafauna went completely extinct in NA/Europe.
Then there is also human factor of hunting these animals for meat and leather but it was probably a combination of factors.
- North American horses (several species)
- North American camels
- Giant Bison
- Tapirs (several North American species)
- Llama's (several North American species)
- Stag Moose
- Gomphotheres (several species, similar to elephants)
Several other species of North American megafauna, such as North American lions and giant beavers likely went extinct due to human activities even though there's no evidence they were hunted directly. e.g. The extinction of most of their prey likely did the lions in.
It's actually quite shocking what humans with rocks, sticks, and empty bellies were able to do. There can be little doubt that the domestication of animals for food has spared countless other species from a similar fate over the last ten thousand years.