Tuesday, March 31, 2026

What Happened to the Population Bomb?

Only you older readers have clear memories of 1968, but I remember it well. That was nearly 60 years ago, and it was a pivotal year in my career. I also remember it because of a book that was published that year, a work that had widespread societal as well as personal impact. 

Paul Ehrlich was the author of The Population Bomb (1968), the book just mentioned. He was born in Philadelphia in 1932, and after graduating from Pennsylvania University in 1953, he received the Ph.D. degree in Entomology (the scientific study of insects) in 1957 from the University of Kansas. From 1959 to 1968, he was a professor at Stanford University.

When Ehrlich’s soon-to-be bombshell book was first released in May 1968, it was initially ignored—no major newspaper reviewed it for four months. Its rise to prominence came through a different route entirely. In February 1970, Johnny Carson invited Ehrlich onto the Tonight Show, and the book soon became a bestseller.

The book received the Bestsellers Paperback of the Year Award in 1970, selling over two million copies. It raised general awareness of population and environmental issues as well as influencing public policy in the 1960s and 1970s.

It should be noted that Paul, with the assistance of his wife Anne, wrote the first draft in about three weeks, based on his lecture notes. The publisher, though, insisted on listing only Paul's name—a decision Ehrlich later called a mistake he was “stupid enough to go along with.” Anne was genuinely the co-author from the beginning.

Paul died on March 13 at the age of 93, and Anne, his wife for 71 years, is still living and now 92 years old.

Why would a biology professor be qualified to write a book about human overpopulation? The answer is found in his emphasis on “coevolution,” about which he wrote a landmark paper in 1964. That work, co-written with botanist Peter Raven, was titled “Butterflies and Plants: A Study in Coevolution and published in the journal Evolution.

Ehrlich’s entomology background trained him to think in terms of populations, limits, adaptation, and ecological relationships rather than just individual organisms. That perspective made it easier for him to frame human population growth as part of a larger biological system with finite resources.

In his ecological studies, Ehrlich repeatedly saw that when a population (of any species) undergoes exponential growth, it then experiences a subsequent crash as it has grown beyond what its environment can support. Since his research led him to believe that to be true, then humanity, he thought, was due to experience a cataclysmic downsizing of the population.

As it turned out, Ehrlich's dire prophecy proved self-defeating. The alarm he sounded was taken seriously enough to trigger responses that averted the catastrophe he foresaw for the 1970s.

Ehrlich himself was a keynote speaker at the first Earth Day on April 22, 1970, helping to shape the day's sense of urgency. In addition, the Green Revolution, international family planning initiatives, and agricultural investment in vulnerable regions also contributed substantially to staving off the outcome he feared.*

Although there were an impressive 8-9 million people at the No Kings protests on March 28, that is far less than half the number estimated to have participated in the first Earth Day activities. However, the latter covered a very broad range of activities while the No Kings figure refers to concentrated, single-day marches and rallies, which makes comparison tricky.

What was averted in the 1970s has been coming true in the 2020s. Since what he predicted in 1968 didn’t come true in the 1970s, Ehrlich changed his position during that decade and later. In the present decade, however, what is happening in the Global South resonates powerfully with his original warning.

The population explosion Ehrlich feared in 1968 largely did not materialize in the wealthy nations he was most focused on, but population growth now is concentrated in the poorest and most climate-vulnerable regions, primarily in Sub-Saharan Africa and other vulnerable regions of the Global South.**

The main issue now is climate-related disasters displacing millions—what many now call “climate refugees.” Drought, desertification, erratic rainfall, and crop failures is displacing large numbers of people primarily in the Sahel region (Mali, Niger, Chad, Burkina Faso) and the Horn of Africa (Somalia, Ethiopia, Eritrea).

Next month, Earth Day will be termed Earth Week, with major activities beginning on April 18 and continuing through April 25. Those activities will likely be much smaller but potentially more important than the No Kings activities on March 28. What will you do for humanity and for Mother Earth that week?

_____

 * The Green Revolution refers to a series of agricultural research and development initiatives, spanning roughly the 1940s through the 1970s, that dramatically increased food production in developing countries, particularly in Asia and Latin America. It was led principally by American agronomist Norman Borlaug, who won the Nobel Peace Prize in 1970.

** The Progress Network posted “The Underpopulation Bomb” in their March 26 newsletter. It is largely critical of Ehrlich’s “prophecy of catastrophe” in The Population Bomb and, contrastingly, writes of the current concern with underpopulation and pronatalism. That article, and the Progress Network itself, is overly focused on the wealthy West and negligent of the population and ecological issues of the Global south.

Note: Research assistance provided by Claude (Anthropic).

 

14 comments:

  1. In the opening paragraph above, I mention "personal impact." I am writing here to say a word about that. When June and I married in 1957, we decided that we wanted to have four children, and we picked out names for all four of them. After 15 months our first child, a son, was born, and in November 1960, his baby sister was born.

    Then we planned to have two more children many years later. But with the emphasis on the dangers of overpopulation and the publishing of Ehrlich's book in 1968, we began to question whether we should complete our family plan. We decided to proceed as planned, in spite of critical comments by those who thought having more than two children was irresponsible. We countered by saying we were going to raise those children to help solve the world's problems rather than making them worse--and we think we did that.

    Our daughter born in 1970 is a professor and administrator at a major state university, and our son born in 1972 is a social studies teacher in the largest high school in the state of Maryland. Last year he was awarded the National Board Certification, "the most respected professional certification available in education." At our bimonthly Zoom family chat last night, he said he tells his students that he might not have been born (for the reasons stated above).

    ReplyDelete
    Replies
    1. Leroy, I appreciate your personal comment about family planning. I can't say I was that intentional about being a parent myself. I will say that a spin-off of Ehrich's writings was a 1972 book — "Limits to Growth" — which became very influential for me. It, along with "Diet for a Small Planet" and "Small is Beautiful", led me in 1976 to run for Congress.

      There was a follow-up in 2012: "2052: A Global Forecast for the Next Forty Years" — which looked back 40 years to 1972 and ahead to 2052. It is very sobering to know that our behavior today may cause serious problems for future generations. I like the comfort of believing that everything is self-correcting, but I know this is wishful thinking. I do find evidence that throughout history, many people have identified problems and developed ways to cope with and manage them, if not solve them.

      Delete
  2. Ehrlich’s book is a follow-up of Malthus’s Essay on the Principle of Population, published in 1798. Malthus predicted that human population growth would eventually outgrow the food supply, but this has not happened, at least so far, because of advances in agricultural technology. Climate change may yet prove Malthus correct.
    The current size of the human population is straining our planet’s resources, but if the earth’s population peaks in a few decades, the demand for the earth’s resources may begin to subside. Many European and East Asian nations already have declining populations. The U S birth rate is now below the replacement level, and 2025 was the first year in decades during which more people left the U S than entered it. If this continues, U S population will also begin to decline.
    The biggest threat, however, is climate change, and I am afraid we may have already passed the “tipping point.”
    Eric Dollard

    ReplyDelete
  3. Local Thinking Friend Johannes Tredoux emailed me the following brief comments.

    "Thanks, Leroy! Very helpful, enlightening, and tragic, considering what is happening in the global south."

    ReplyDelete
  4. In 1968 started my degree at Wye College, the School of Agriculture and Horticulture for the University of London, UK. I was aware of Ehrlich's thesis. I was also aware of the 'Green Revolution.' Norman Borlaug, from Iowa and father of the Green Revolution, won the Nobel Peace Prize in 1970. He perhaps saved a billion people, more than any other in history. In 1972-1976 I worked on a PhD in plant genetics at the University of Wales, Aberystwyth. My fellow graduate students and I were inspired by Borlaug. Perhaps you could do a blog on Borlaug sometime Leroy!

    In 1986 Borlaug founded the World Food Prize. I have a friend from Wye College days, Miles Hillmann who is writing a book "The Super-Seeders" on a recent winner of the World Food prize - Dr Geoffrey Hawtins for his work on gene banks. Malthus and Ehrlich were pessimistic but warned us. Scientists like Norman Borlaug prevented their gloomy prophecy coming to pass.

    ReplyDelete
    Replies
    1. Thanks for your very pertinent comments, Andrew. -- It was perhaps before you started reading my blog posts, but here is a link to the blog article I posted about Borlaug back in December 2029:
      https://theviewfromthisseat.blogspot.com/2019/12/the-man-who-fed-world.html .

      I don't know that Malthus and Ehrlich were especially pessimistic, they were just going with the information and the status of the world at the time they were writing. But as I tried to say, at least Ehrlich's "gloomy prophecy" was to a large extent self-defeating prophecy.

      Borlaug and Ehrlich knew each other, and according by Claude, "they agreed on the problem more than history usually acknowledges, differed on solutions, and Borlaug himself refused to let his Nobel moment be used as a simple rebuttal to Ehrlich's warnings."

      Delete
  5. A Thinking Friend in New Mexico sent the following comments:

    "I remember being in high school when the book came out. My school quickly began to have conversations about zero population growth. As a result, my wife and carried over the desire to limit our family to two. It is interesting that his predictions did not come true until the 2020s. Is it possible that his book made a significant difference.

    ReplyDelete
    Replies
    1. I think his book definitely made a significant difference, which is largely what I meant by calling the prediction he made in the book was a self-defeating prophecy.

      Delete
  6. And then this, from a Thinking Friend in Arkansas:

    "Thank you for this excellent piece, or should I say reminder. Born in 1959, I do not remember Ehrlich or the book, but I remember a time when many were talking about overpopulation of the planet. Was it Ehrlich that prompted this response?

    ReplyDelete
    Replies
    1. Yes, I think it was certainly Ehrlich that caused the talk about overpopulation, even though that had died down considerably by the time you were in college, largely because of the Green Revolution. But far-sighted people realized that the increased production of food in the 1970s was not going to be a permanent solution.

      Delete
  7. This afternoon, I received an email from a local Thinking Friend with these comments:

    "I remember Ehrlich and his thesis. I agree that he may well have been the impetus for changes made after his book was published. My current concern, with draught, food shortages and gang violence in so many territories in Africa and the Americas, is that there will be armed intervention to halt migrations instead of humanitarian efforts to assist our sisters & brothers who are in desperate need. As you noted, it's already heading in that direction."

    ReplyDelete
  8. "Understanding the fragility of our planetary home: The legacy of Paul Ehrlich" is the name of a March 31 article on website of the Bulletin of the Atomic Scientists."

    ReplyDelete
  9. I remember the book vaguely and the first Earth Day. We can rejoice that population growth has slowed in some areas, but as you say, has not slowed in the areas who can least afford it. I wonder how the increased impact of climate change will affect the Green Revolution for food production in the future. Will they cancel each other out with negative results predominating?

    ReplyDelete
  10. Well, I actually have a reason to be a little late posting this time, and it relates directly to the subject. My daughter, with whom we live, had a baby Tuesday, March 31. I now have three children and three grandchildren, with a good chance of having no more. So, with a surprise baby I went over the replacement number of 2.1, but with just three grandchildren I am under the grandchild replacement number of 4.2. Which is to say, this is both a global issue and a very personal issue for all of us.

    Borlaug is often cited as the very reason that the population bomb did not explode shortly after the book was written. His green revolution greatly increased both crop yields and nutritional value around the world. However, it came with a great hidden cost. Subsistence farming was replaced by complex hybrid seeds and procedures, including heavy use of nitrogen fertilizer. As we watch anthropogenic global warming and what some are already calling WW III in the middle east, we may finally be in the midst of the explosion of the population bomb. Global warming was already heading us slowly towards a population disaster, and now the war crimes of America and Israel are causing Iran to drastically cut the world supply of fossil fuels; which might look good for global warming, but is a disaster for the green revolution, which depends on fossil fuel for both tractors and fertilizers. It is planting season over much of the world, and crops may not get planted without enough fuel and fertilizer. I have seen estimates that we might be heading for starvation for as many as two billion people. Yes, that is "billion" with a "b." Smaller numbers in shorter timeframes are still urgent, but since it may take years to get LNG back online in the middle east, the final tally may be much higher. Here is a sample report from NBC: https://www.nbcnews.com/world/iran/iran-war-shatter-global-food-security-rcna265585

    ReplyDelete