Mega fauna extinction?

Question

If the human species is responsible for the extinction the of the Mega Fauna and humans started out in Africa, then why did all the mega fauna in Australia become extinct before that of Africa’s?

Answer 1

if we assume it is the humans' fault, then my guess would be that Africa is a lush, expansive habitat that allows for many niche positions, large and small.

On the other hand, Australia is a harsh environment, with little room for error. If humans came around and took the few niche's available, it would put the mega fauna out in the desert without a chance.

Then again, maybe it's the climate & other factors, and humans aren't the only source of extinction!

Answer 2

Apparently, the last of Australia's megafauna died out about 40,000 years ago, which was about the same time Aborigines arrived here. I imagine the main reason they all died out was more due to climate change, or whatever else was going on back then, than human interference.
Just a couple of points to another poster...we don't have polecats in Australia. We have wild cats, but they are just domestic cats that have gone wild and bred etc. Also, I don't know of any marsupials that have died out since foxes etc. have been introduced. There may be a couple but I'm not sure of that, and if there were many, I think it would be well known here. The only animals that I know for sure have become extinct in the last few hundred years, which obviously doesn't include megafauna, are the Tasmanian tiger and the Paradise parrot. The Tasmanian tiger was shot to extinction by farmers, a very sad loss to the world. The Paradise parrot nested in ant hills, so was a target for foxes, and it was another sad loss to Australia and the world.
Foxes and wild cats are very happy to eat rabbits, but they do also kill a lot of birds, lizards and other wildlife. They are way too small to kill most marsupials.

Answer 3

The African fauna evolved gradually, over millions of years, in the presence of (also evolving) homonids. They had ample opportunity to interact and adapt to each other to co-exist (as evidenced by the fact that they did).

In North America and Australia, the fauna had humans thrust upon them (so to speak) over a much shorter time frame. In those cases, humans were an "invasive species" and the local organisms didn't have enough time to adapt before they were driven extinct through human action.

Answer 4

The megafauna in Australia was under pressure and the number of species was dropping before the arrival of humans in Australia (dated anywhere from 120k-40k bp)
The Pliocene fossil record is pretty clear about that.

The nail in the coffin for them was the changes to the envrionment caused by humans mainly a big change in fire regimes and also competition for limited resources like water sources. There's very little eveidence for predation by Aboriginals to date, at most archeological sites the megafauna appear in the record, then artifacts start appearing, but nothing contempraneous.

Australia is a very marginal environment, and the changes humans wrought were huge, but some diprotodons struggled on until about 6000bp, so it wasn't a super quick demise.

Does that help?

Answer 5

Humans introduced some destructive species to Australia that marsupials just can't compete with.
The big one was rabbits in the 19th Century, which took over and simply can't be eradicated without every citizen going out and hunting them, so they introduced predators like foxes and polecats to curb the rabbit problem but now it is even worse, because they prey first on marsupials before they ever get to the rabbits.

Answer 6

Because even though the exploration of Europeans began in Africa, it was far more extensive in Oceania (Australia and other Pacific Islands). Therefore, the damage there occurred much quicker.