The scariest thing about Halloween last year was not the 6-year old goblins running around Boulder neighborhoods, although some of them were pretty scary. It was the fact that October 31 was designated as the official day when the human population reached 7 billion. For many people, this fact doesn’t mean much. But it has an ominous meaning. The human population continues to grow and grow and grow and grow.
This latest number means that we have added the most recent billion people to the human population in less than 12 years. It took about 3 million years for the human population to reach 1 billion at around 1800 (or about 200,000 years if you just count our modern species, Homo sapiens sapiens). It means that the human population has doubled in the past 44 years (or less). But in prehistory, it took 100,000 years or more to double. At this rate, we will reach about 13 billion by 2050 and 25 billion by the end of this century. Most population experts dismiss this possibility, but population experts in 1925 said that the human population would never reach 2.5 billion. We passed that number in 1949.
My mother, who is 95, and her sister, who is 98, have both seen the world population quadruple in their lifetimes. I was born in 1938, and it has tripled in my lifetime. Before now, no human being ever saw that happen. This is a unique time in human evolutionary history.
Demographers say this growth will not continue. They project much lower numbers. But at a meeting of the American Association for the Advancement of Science in 1991, I asked Paul Demeny, an internationally recognized demographer and editor of Population and Development Review, how he arrived at much lower population projections than I have stated here. He said, “This requires the informal insertion of unspecified assumptions.” Most of us call this (wink) a “fudge factor.”
In my opinion, the lower numbers are a lot of hot air and wishful thinking unless, of course, we have large die-offs of the human population. This is likely to happen because there is no evidence that the human population as a whole will voluntarily limit its fertility. Certain individuals and societies have limited fertility in the past and are doing so now, but in general, the human population will continue to grow until mass mortality intervenes.
What are the possible sources of mass mortality?
• Global warming caused by human activities leading to climate changes that result in forest fires, deforestation, loss of glaciers and polar ice, severe weather, crop failures, reduction in the availability of fresh water, and intolerable heat levels increasingly incompatible with human life;
• Catastrophic loss of many plant and animal species on which humans depend including exhaustion of world fisheries;
• Increasing contamination of air and water with toxic materials produced by industrial society;
• Epidemic disease exacerbated by chronic and acute malnutrition and famine conditions in the most vulnerable populations;
• Epidemic mass conflict and violence resulting from desperate competition for increasingly limited resources.
Are these things in the future? No. They are happening now. If you like what the 20th century brought us in terms of war, famine, pestilence, and ecological destruction, you will love the rest of this one. It will be worse.
The scariest thing about the current political campaign for the U.S. presidency is that all the leading Republican candidates reject not only these widely known facts and reasonable approaches to solving these critical problems, they are all against all forms of effective fertility control that Americans want, need, or are currently using. They compete with each other for the most medieval policy and attitude toward women. They reject increasingly certain observations and projections of global climate change as a hoax. They dismiss the certain consequences of these ominous changes as “pseudoscience.” They make it increasingly difficult to consider increasingly urgent and necessary responses to these changes.
Unfortunately, the list of horrible problems given above is not the worst part. The worst part is in understanding the dynamic interactions of what is happening.
Humans have been a successful species because we can adapt to almost any ecosystem. “Adaptation” is something that has survival value. But many of our adaptations have become maladaptive. They do not have survival value. Although our bodies have not changed much in 200,000 years, our cultural adaptations have allowed us to survive and dominate the planet in ways that have become extremely maladaptive. I call these “malignant maladaptations.”
We humans have become a pathological process — a malignancy — in the planetary ecosystem. The human species now displays all the major characteristics of a malignant process.
A malignant process continues until the host organism ceases to function — it dies. Our “host organism” is the global biosphere. It won’t die, but we are altering it so that it cannot sustain either humans or many other species. Sooner or later, that is the end of us.
This is not an analogy. You don’t die from an analogy. It is a diagnosis. It is a hypothesis. A hypothesis explains reality and predicts events. This hypothesis/diagnosis explains what is happening, and it predicts that we will keep doing what we are doing until there are not enough of us left to do it. I would like to be proven wrong.
The difference between us and a cancer is that we can think, and we can decide not to be a cancer.
We have a presidential election coming up. We can choose to think — or not. We can choose candidates and public officials who value thought and facts, who understand the global ecological realities we face, and who lead us in the direction of reasonable responses that have survival value for us and other species, or we can choose leaders who deny both facts and thought and who want to lead us right over the cliff just ahead. This election is about that choice.
Warren M. Hern is a population epidemiologist who practices medicine in Boulder and has academic affiliations with the University of Colorado Boulder and the University of Colorado Denver Health Sciences Center.