Quote:
Originally Posted by Ladogaboy
I'm sorry, I still don't buy the goats. Comparing the savannah that once occupied the Sahara to the American Great Plains is a bit of a stretch. Humans were introduced to North America at a time when the animals were no longer equipped to deal with that kind of a pack hunter. The bison were about the only ones who were, and that is why the Europeans saw such a homogenous ecosystem when they arrived. And the Dust Bowl was the result of killing off the buffalo (which had been eating the grasses in much the same way as goats) and poor plant-based agricultural practices. And if you want to say that climate had little to do with it, then, by that logic, the American Great Plains should still to this day look more like the Great Sandy Desert... but it doesn't. The Sahara savannah had none of those factors. If anything, it would have appeared most similar to South central Africa, where the animals are VERY well equipped to deal with pre-modern humans.
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Just on this point:
I would say that millennial long Climate change would be the major factor. Over the time span it can turn plains into desserts and back again. However there is a very valid point that animals can have a significant effect between transitions of grassy or scrub land into desserts. I saw a documentary years ago that i can't recall about an invasive mouse like species i believe in australia. They would eat the seeds of the plants and burrow into the ground disrupting the soil. Of course without natural predators things get out of hand. And year after year you get miles of the ecosystem collapsing into desert. Eradicating the animal saw a rebound of the grassy scrubland into its natural range.
Small things like that can have a big impact on emergent species in transition zones. And the difference between zones will dramatically affect water and temperature. Any foriegn thing that does something unatural to the environment can do this, be it livestock or agricultural practices. I doubt killing buffalo contributed to the dustbowl in any meaningful way over the way it was farmed. However even the buffalo had their place in the health of the plains and predators. Also the plains are not a transitional zone into you get far into the west.