Population Growth: Boom or Bust?

It took tens of thousands of years for the first humans to migrate from Africa across the world. In that time, the Neanderthals disappeared, ice ages came and went, and agriculture first took root. In a lecture tonight at BU, demographer Joel Cohen, a professor of populations at New York’s Rockefeller University, where he is Abby Rockefeller Mauzé Professor, and at Columbia University, will cover all those millennia in about an hour.

Cohen is this year’s Frederick S. Pardee Center for the Study of the Longer-Range Future Visiting Professor of Future Studies. He will give the first of five lectures in a series titled The Human Population: Past, or Passing, or to Come today at 6 p.m. at the School of Management. Other lectures will follow over the next two weeks, looking into the future of human population growth and development and posing questions about how many people the Earth can support and whether sustainable development and democracies are compatible.

After whisking the audience through the ages of human population growth, noting that it took until 1900 to reach 1.6 billion people and just 100 years more to hit 6 billion, Cohen will discuss “the fact that there are really two planets on this Earth: the rich world and the poor world.” Between 80 and 85 percent of the Earth’s population lives in the latter, according to Cohen.

A member of the National Academy of Sciences since 1997, Cohen specializes in using mathematical and statistical models to research the ecology, epidemiology, and social organization of human and nonhuman populations. He has written 13 books, including Educating All Children: A Global Agenda, published this year by MIT Press. “Joel Cohen is arguably the leading demographer in the world,” says University Provost David Campbell, a member of the Pardee advisory board that chose this year’s visiting professor.

Cohen’s second lecture, which will take place on Tuesday, October 2, will peer half a century into the future, a period during which Cohen estimates that the Earth will have to accommodate three billion more people, mostly in the urban centers of poorer countries.

His third lecture will pose a big question, also the title of one of his books: how many people can the Earth support? Estimates made in the last 50 years have ranged from one billion (in which case we’re already overbooked) to more than a trillion, Cohen notes. He says this question can be answered only after factoring in issues such as technology, water resources, and disease. When asked about his own conclusions, he quipped, “I’m just interested in the questions. You can answer them.”

The fourth lecture will look at the benefits of providing high-quality education to every child on Earth — higher quality of life, more effective governance, a world economic boost, and a lower birthrate in resource-poor nations — and why universal education has been so hard to achieve.

Finally, Cohen will parse buzzwords like sustainability, globalization, and democracy and explore the tensions among them.   

“The last topic is one I have never spoken about before, anywhere,” he says. “It’s something I’ve been thinking about for some time, but haven’t had the courage or the opportunity to go into until now. I’m really looking forward to getting some critical comments on it.”

The Pardee Center for the Study of the Longer-Range Future was established in 2000 by a $5 million gift from Frederick S. Pardee (SMG’54, GSM’54). Past Pardee Visiting Professors have included Nobel Laureates Amartya Sen and Murray Gell-Mann. Joel Cohen’s lectures will take place in the SMG auditorium, 595 Commonwealth Ave., as follows:

The Human Population to Now, Monday, October 1, 6 to 7:30 p.m.

The Human Population to 2050, Tuesday, October 2, 6 to 7:30 p.m.

Human Carrying Capacity of the Earth, Tuesday, October 9, 6 to 8 p.m.

Educate All Children Well to Prepare for an Uncertain Future, Wednesday, October 10, 6 to 7:30 p.m.

Sustainability, Globalization, National Democracies: Are They Compatible? Friday, October 12, noon to 1:30 p.m.

Chris Berdik can be reached at cberdik@bu.edu.