[Smokin' Joe]

Maybe someone can throw in a timeline which would put that idea in perspective, but I wonder how much of this was related to the development of technology which enabled more efficient hunting of upland animals, herd forming herbivores, and possibly domestication of dogs for hunting partners and guards.

It could be something as simple as the development of improved hide tanning methods and better shoes.

I know that may seem a stretch, but new horizons become available to those who adapt, and the most simple seeming technologies often make that possible.

[Does so]

"Maybe someone can throw in a timeline which would put that idea in perspective..."

From memory:

1) "domesticated dogs" were present about 100,000 years ago

2) A population bust—which left only 10,000 humans—occurred around the time of this population "explosion".