I just ran across a link describing this study this morning:
Hunter-gatherers, Westerners use same amount of energy, contrary to theory
“Modern lifestyles are generally quite different from those of our hunter-gatherer ancestors, a fact that some claim as the cause of the current rise in global obesity, but new results published July 25 in the open access journal PLoS ONE find that there is no difference between the energy expenditure of modern hunter-gatherers and Westerners, casting doubt on this theory.
These findings upend the long-held assumption that our hunter-gatherer ancestors expended more energy than modern populations, and challenge the view that obesity in Western populations results from decreased energy expenditure.”
Reading this shocked me, as most anthropological studies I had ever seen made the point that hunter-gatherers typically never worked as hard as modern Westerners. Lee and Devore’s famous studies of the !Kung San living in the desolate Kalahari Desert showed that they spent more time socializing and taking naps than they did in the quest for food. In fact they only looked for food every three or four days.
Years ago, Jared Diamond used this loss of leisure time as one of the reasons he believed the shift to agricultural subsistence was The Worst Mistake in the History of the Human Race.