The United Nations has identified Monday as the day world population hits 7 billion. Many find the Halloween date appropriate given the frightening prospect of this demographic milestone. As if 7 billion weren't scary enough, the U.N. projects 10 billion people by 2083, the addition of roughly three more Indias.
But the parents of the 7-billionth person should not be afraid for their child's future. In spite of the daunting challenges facing the world, including global warming, rising food prices and a billion people in poverty, the 7-billionth child will almost surely have a better life than the 3-billionth or 6-billionth child.
How will the world cope with this many people? Consider what the world looked like in 1960, when the population hit 3 billion. Falling infant and child mortality caused population growth rates to surpass 2% per year in the 1960s, probably for the first time in history. At 2% growth, the world would double in 35 years, and that is roughly what happened — world population grew to 6 billion in 1999. World population will not come close to doubling again in 39 years. Indeed, it may never double again. Fertility has fallen rapidly, with many developing countries at or near the replacement fertility rate of 2.1. The world's population growth rate has been falling since its peak in the 1960s, and we may never get much above the 10.1 billion people projected for 2100.
So we've just been through the fastest population growth the world will ever see. It's a good time to look back and see how the world survived it.
There were gloomy predictions in the 1960s about the consequences of rapid population growth, the most famous appearing in Paul Ehrlich's 1968 book, "The Population Bomb." He wrote that "the battle to feed humanity is already lost, in the sense that we will not be able to prevent large-scale famines in the next decade."
Happily, Ehrlich was wrong. World food production grew faster than population during the last 50 years. Food production per person in 2009 was 41% higher than in 1961.
No country generated more fear about overpopulation than India. But food production there has grown faster than population since the Green Revolution of the late 1960s. Food production per person in India today is 37% higher than in 1961, although there are 2.6 times more people.
Although there are still serious problems with food distribution and malnutrition, we have done remarkably well at feeding the extra 4 billion people added since 1960. This should make us optimistic about feeding the 3 billion more to be added in the next 70 years.
Increased food supply is one reason that children around the world today are the healthiest ever born. An Indian baby born in 2011 has almost double the probability of surviving the first year of life as a baby born in 1960.
The 7-billionth child will also be better educated than a child born in 1960. Big increases in education in the developing world are one of the most impressive accomplishments of the last 50 years, especially given unprecedented growth of school-age populations. Only about one-third of Indian girls born in 1960 completed primary school, compared with about three-fourths of those born in 1990. For an Indian girl born in 2011 the rate will be even higher.
The probability that a child will grow up in poverty has been going down. For developing countries as a whole, the percentage living below the World Bank's $1.25-per-day poverty line fell from 50% in 1981 to 25% in 2005. India's poverty rate fell from 60% in 1981 to 42% in 2005 and can be expected to keep falling.
Not all countries have done as well as India. But even in sub-Saharan Africa, the region with the poorest economic performance, poverty rates have fallen, education has increased and food production per person has been rising (albeit slowly) since the 1980s.
None of this is meant to deny the enormous challenges we face. We survived the population bomb through hard work and creativity, and we will need more of it to continue to feed the world and reduce poverty. But the remarkable experience of the last 50 years teaches us that we should not be afraid to celebrate the birth of the 7-billionth child.
By David Lam, a professor of economics at the University of Michigan and president of the Population Assn. of America.