Around 12,000 years ago, what was the main effect of population pressure and changing climate conditions on modern humans

At the early stage of development humans lived as nomads, they would stay in one place until they ran out of provisions that were available and then moved elsewhere. But when the groups of humans started to get bigger and the climate conditions started to change. Around the Neolithic era - about 13 or 5 thousand years ago - humans faced a new challenge.

Groups of humans were bigger, it was harder to fins food for everybody, so they began to domesticate plants and animals, such as sorghum, rice, groundnuts, and yams. They started to live in semi-subterranean houses built of stone and wood because now they didn't have to change places very often. Later it came animal domestication, it started with goats, sheep, pigs, and cattle.

This change of way of living changed the course of human history and made our lifestyle possible.