What is going on here is the substantial impact of absolutely staggering infant and child mortality. Under these assumptions, by age 10, fully 50% of all children born are already dead; only about 45% of all children make it to adulthood as we generally define it (around 18 years). And as a reminder that is only for live births – we have not yet considered miscarriages, stillbirths or maternal mortality. This enormous child mortality rate is not an accident of a particular ancient society, but in fact an absolute constant for all pre-industrial societies, be they hunter-gatherers, pastoralists or farmers, be they urbanized or not, ‘civilized’ or not, ‘western’ or not. For all societies, everywhere at every time before about 1750 (and in most places for a long time after that) it was simply a fact of life that half, HALF of all children died
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stares at a wall
