In the Paleolithic Age we had to get food by hunting animals or gathering plants. We did not have a stable or dependable food supply.It was dangerous because we were always on the move and it was dangerous to be hunting because the animals were dangerous.
One of our changes that helped us was that we were able to plant seeds and harvest crops.
Early farmers also learned how to domesticate animals or raise them for peoples needs.
These two thing helped because we could have a stable food supply and our farmers could help us for our needs.