From time immemorial, the human population on Earth has been remarkably stable. Over extended periods and many generations, the number of births almost perfectly equaled the number of deaths. Women bore many children but most were lost before reaching adulthood. Plagues, famines, and infections kept populations in check, and some control over births was exercised through abstinence, breastfeeding, and infanticide.
About three hundred years ago, this all began to change. Plagues became less frequent and less virulent. Sanitation and nutrition improved. And in some small, rural villages in France, toward the end of the eighteenth century, couples began to systematically limit the numbers of children they birthed. We don’t know how they achieved this or why; we know that birth patterns changed in a way that can be explained only by deliberate control.
The reduction in human births and deaths—the “Demographic Revolution”—has touched every community on Earth. The French controlled births before they controlled death and so the French population grew slowly in the nineteenth century. The British brought their births under control a century after the declines in mortality, and in the century in which births outstripped deaths, the British Isles exploded with people who spread out over the empire.
The Demographic Revolution isn’t over. Humans are still in the midst of dramatic reductions in both births and deaths, as Paul Morland explains in Tomorrow’s People. Morland is a senior member of St. Anthony’s College, University of Oxford, and this is his second popular book on demography. He cuts through the complexities by telling a story of the human race in ten numbers: infant mortality, population growth, urbanization, fertility, aging, old age, population decline, ethnic change, education, and food.
Morland shows how different mixes of births and deaths within and between countries are shared through migration, and what that means for the future of nations and states. And although the developed world is fixated on living as long as possible, Morland shows that our future depends not on extending life spans, but on the birth rate, which continues to decline. Group survival is determined by the production of children. At a time of almost perfect birth control, births are no longer determined by biology, but by culture and, particularly, religion—any and all of them—because most religions promulgate the idea that life is worth reproducing. In a world that is dominated by secular values, there is only one developed country birthing enough children to replace its adults. (Have you guessed which? Read on to find out.)
Why do we moderns wish to live forever but not wish to have children? Morland can’t answer this question; no discipline has been able to answer it. But he gives us a view of what happens to countries when its people live ever-longer lives and have ever-fewer children.
Morland’s story begins with death at birth. In Swedish villages two hundred years ago, more than 40 percent of infants died within a month of birth. Who can imagine such loss? And yet this rate of death was typical worldwide. Today, the U.S. infant mortality rate of 5.5 per 1,000 is high compared to Western Europe’s, but that’s half what it was in 1980. Eliminating death at birth has been the largest contributor to quality and quantity of life. Women today everywhere give birth with some confidence that they will survive the birth and that their babies will survive to adulthood.