Fertility versus productivity: A model of growth with evolutionary equilibria

We develop a quantitative model that is consistent with three principal building blocks of Unified Growth Theory: the break-out from economic stagnation, the buildup to the Industrial Revolution, and the onset of the fertility transition. Our analysis suggests that (i) the escape from the Malthusian trap was triggered by the demographic catastrophes in the aftermath of the Black Death, (ii), household investment in children ultimately raised wages despite an increasing population, and (iii) rising human capital, combined with the increasing elasticity of substitution between child quantity and quality, reduced target family size and contributed to the fertility transition.