Source: Joel E. Cohen, Abby Rockefeller Mauzé Professor of Populations, Rockefeller University; Professor of Populations, Columbia University; Head of the Laboratory of Populations, The Earth Institute at Columbia University and Rockefeller University.
Roberta Balstad: …session we're addressing various aspects of the issue of human behavior, social behavior, religious, cultural, institutional behavior, and trying to understand how we reconcile the individual and the society in the course of implementing sustainable development. I'm very pleased to introduce our first speaker today. Professor Joel Cohen is Professor of Populations at both the Rockefeller University and Columbia University. And he is the Director of the Laboratory of Populations which also exists in both places. Joel combines opposites in his work and in his life. He is the recipient of two PhDs, he holds a PhD. in applied mathematics and a PhD in population and public health, both from Harvard University. He is a member of the National Academy of Sciences, and he has written hundreds of articles and a dozen books, most of which were prize winning books. He will be speaking today on Education in Developing Countries. Joel.
Joel Cohen: Thank you, Roberta. I'd like to thank Jeff Sachs and John Mutter and the organizing committee for inviting me, and I'd like to thank you for sticking around to converse with us.
There are two parts to my talk. One is I'd like to set the context, and the second is I'd like to explain how the context makes education in developing countries and elsewhere very important. We live on our world, one planet but two different worlds. There's a rich world and a poor world. The rich world has an average income of about 26,000, the poor world about 4,500. Less than one in five on the planet live in the rich world, more than four or five out of six live in the poor world. The rich world is increasing a tenth of a percent per year in population, the poor world fifteen times faster. The poor world has three times the rate of HIV/AIDS. An infant born in the poor world has ten times the chance of dying within the first year of life compared with an infant born in the rich world. The total fertility rate, the average number of children, born per lifetime of a woman in the poor world is twice that in the rich world. A newborn baby lives ten years shorter on average in the poor world, has half a chance compared with the rich world of living in a city, and something not widely recognized is that the population density is about two and a half times greater, the number of people per square kilometer. You might not think that here in New York City, but in fact the wide open spaces are in the rich world, not the poor world.
So I want to tell you a summary of where we're going in the next fifty years with population, and the details are in the article in Scientific American called “Human Population Grows Up,” which everybody got with your packet, the first article.
It's projected that we'll go to 9.1 billion people, but if women have half a child more than anticipated in this continuing fall of fertility we'll go to one and a half billion more. If women have half a child less, we'll go to almost one and a half billion less. In other words, a one child difference in behavior per woman means a three people billion difference by 2050, which emphasizes the importance of what we do right now. That increase of three billion will not be uniformly distributed over the Earth. It will be entirely concentrated, except for a few percent, in the poor countries. And here is an illustrative comparison. On the left we take twenty-five countries of the extended EU, on the right twenty-five countries of what would be imprecisely called the Middle East, north Africa and western Asia. In 1950 Europe had twice the population of north Africa, 350 million versus 163 million. By 2000 the Middle East had more population than Europe. By 2050 the Middle East will have three times the population of Europe. That's a colossal change in one century. That change is reflected in an enormous difference in age structures. These things are called age pyramids. The width of the bar is the number of people, like that's, I don't know, 35 million people wide, and the lowest bar is people age zero to four, the next bar is age five to nine, fifteen [he meant to say “ten”] to fourteen, up to ninety-five to a hundred. When the pyramid, this is today's pyramid in the Middle East, when the bottom bar is wider than the bar just above it, it means that more people are being born in the last five years than in the five to ten years before that, and that's more than the people who were born ten to fourteen years before that, because everybody gets one year older each year among those who survive. And what you see is a middle aged bulge here in Europe, most people in the middle age groups, and a very wide bottomed pyramid here, meaning extremely rapid growth. If you go to 2050 this bulge will have aged up to the top, continuing contraction in Europe, Europe will in fact be decreasing in total population size, while the Middle East has an enormous youth bulge down here. So there will be a shift not only in numbers, but a shift in age composition. These are the people of school age, compare, and these are the people of military age, compare.