...The Black Death led to an improvement in agricultural technology, changed the status of women, and increased wages. This process helped the Industrial Revolution, but the technology boom was not profitable in low-income countries. These findings suggest an underlying problem of development could be the demographic patterns that keep wages low...

...In more detail, Voigtländer and Voth (2013) argued that the scarcity of labour after the Black Death led to a change in agricultural technology. Moving along the wage-rental iso-productivity line, farmers changed from growing crops to tending animals, from arable farming to husbandry. In other words, movement along a smooth production-possibility curve resulted in a discrete change in the underlying technology. Thomas More expressed it most colourfully: “Your sheep that were wont to be so meek and tame, and so small eaters, now, as I hear say, have become so great devourers and so wild, that they eat up and swallow down the very men themselves. They consume, destroy, and devour whole fields, houses and cities.”

This adaptation of agricultural technology changed the role of women in Medieval Europe. Switching from crops to husbandry reduced the demand for strength to push plough and expanded the scope of work that women could do. The result was a change in the status of women in society that economic historians have observed at other times and places. The reduction in ploughing reduced the demand for men’s labour and increased the one for women’s labour. Women’s wages rose and their opportunity for work expanded. They delayed marriage, entered service, and became more independent. This, in turn, led to the European marriage pattern and the family pattern described by Hajnal (1965). It was a unique change in the structure of society, consisting of later marriage of women, separate households for newly-married couples, and increased frequency of single women, later known as spinsters...

...The rise in wages as a result of the Black Death was sustained by a shift in marriage patterns that increased the age of women’s marriage, and reduced the rate of population increase. The adaptation to the initial shock led to a durable rise in people’s income. This, in turn, led to a demand for more meat in their diet, which, of course, was accommodated by more husbandry. The whole pattern fit together with the Black Death as a shock that shifted households and the economy from one demographic equilibrium to another.

This research dovetails with Allen’s argument that the initial innovations of the Industrial Revolution emerged from tinkering by producers to reduce the costs of expensive labour and reap the benefits of cheap power. In response to the awareness that wages were generally high in western Europe, Allen (2009) went to some lengths to show that the small gains from these initial innovations were not profitable in either France or the Netherlands...

...The reasoning presented in this column suggests that attention to demography is a large part of economic development. Short of a plague, the best way to raise wages is to reduce the birth rate by changing the role of women in developing countries, in order to bring them closer to the European marriage pattern. This, of course, is very difficult in areas where radical Islam, like the Taliban in Asia, or Boko Haram in Africa, oppose the education and employment of women. Many problems of economic development may be religious and political.