The current study finds that societies which historically engaged in plough agriculture today have lower fertility. We argue, and provide ethnographic evidence, that the finding is explained by the fact that with plough agriculture, children, like women, are relatively less useful in the field....

Powerful currents have reshaped the structure of families over the last century. There has been (i) a dramatic drop in fertility and greater parental investment in children; (ii) a rise in married female labor-force participation; (iii) a significant decline in marriage and a rise in divorce; (iv)...