There's also the fact that throughout the history of civilization we have to spend more time working to exist as population density increases. India 70 hour average working week, European cave man 20 hour working week, one mammoth is a lot of food.
There's also the fact that throughout the history of civilization we have to spend more time working to exist as population density increases. India 70 hour average working week, European cave man 20 hour working week, one mammoth is a lot of food.