Published Jan. 1, 1999
My first novels had all dealt with historical themes, and involved the past returning to disturb the present. With Double Helix I decided to try something different. The action is all present-day and deals with a problem that’s usually displaced into the future and treated as science fiction—over-population. But of course you can argue that this is a contemporary problem, the problem that underlies all the others.
I set much of the novel in Florida because it’s a location that seems to sum up the contemporary world: although the ending of the book, in a Brazilian favela, closer to the life most of the world's inhabitants know. At the centre of the story is a sexually selective contraceptive, a contraceptive that would allow only the birth of males. This, of course, is the most brutal solution to the population problem, since total population is ultimately dependent on the number of females. And it’s a solution which is already being implemented, especially in Asia, either by the abandonment of female children or infanticide. This isn’t a pleasant theme, and because I wanted to treat it objectively—rather than being ‘politically correct’—it’s the least popular of my books. Still, over-population—and all the calamities that flow from it—is not a problem that’s going away.
THE POPULATION PROBLEM
The Growth of the World’s Population
In 1900, the population of the world was 1.5 billion people; by the end of the 20th century it was 6.1 billion, an increase of 400%. Today, world population is around 7.2 billion, though the rate of increase has now slowed, so that estimates to the end of this century foresee a rise of only 50% to about 11 billion: which, I fear, must make one suspicious of the word “only.”
This should be seen in context. A table of population estimates prepared by the US Census Bureau shows that world population in 10,000 B.C. was around 1-10 million (high estimate-low estimate); over the next ten thousand years, that is, to 1 A.D it increased to 170-400 million. Over the next thousand years, that is, to the end of 1000 A.D. the number increases to 254-345 million; over the next five hundred years, to 1500 A.D., it rises to 425-540 million; over the next 250 years, to 1750, it increases to 600-679 million; and over the following 200 years, to 1950, the number rises incredibly to 2,400-2,558 million, an increase many times greater than the human population in the preceding 11 thousand-plus years. And then, I’m afraid, things gets serious. Over the subsequent fifty years, from 1950 to 2000, the population of the world rose from 2.5 billion to 6 billion people. The last part of this series—from 1750 on—is called “the modern rise in population.”
Examined more closely, it’s hard to find grounds for reassurance in any aspect of this. First, it’s worth noting where the greatest population growth has occurred. In 1900, the population of France was 38 million, Mexico 12 million. By the year 2000, France had a population of 58.9 million, while Mexico’s population had grown to 97 million. This is broadly indicative. Since 1950, Asia, Latin America and Africa—the “less developed world”—have seen the greatest population increases, and that will continue into the future. In 1950, the population of Africa was about 9% of the world’s population, but by 2050 this will increase to 24%. As part of these trends, the world has also seen a remarkable increase in urbanization and population density. In 1950, about 30% of the world’s population lived in cities; this is now about 50%. In the developed world, from 1950 to 2000, population density has grown from 15 to 23 people per square kilometre, while in poorer countries the increase has been from 9 to 40. The population density of the Netherlands is 400 people per square kilometre; in Bangladesh, 1050.
The Consequences of Over-Population
But who cares? After all, people are a good thing, and we all love babies. In considering this question, it’s important not to see population growth in isolation; it interacts with many other social, economic and political variables. For example, population growth is often cited as a reason for the extraordinary strain on the world’s resources, and the degradation of the global eco-system; and so it is. But of course this is not divorced from patterns of consumption. Less than 20% of the world’s population is responsible for over 50% of global carbon dioxide emissions. In China, population increased by a little over 10% between 1900 and 2003 but carbon emissions increased by over 80%. Both affluence, and the technological means of acquiring it, are crucial to the status of the world’s environment—as environmentalist are quite right to point out. But there’s a difficulty. It’s hard to imagine development in the less developed world—where population has enormously increased and is still increasing—without increasing consumption. And it’s hard to imagine that such increasing consumption will be matched, in the developed world, by anything like an equivalent decrease. Ultimately, the accession to “developed world” status for the “less developed world”—given the enormous populations involved—must involve a tremendous strain, possibly breakdown, of world ecological systems. In the same way, it’s worth looking at the original anxiety about overpopulation: famine.
This was the great fear of Robert Malthus (1776-1834), perhaps the oldest name to be associated with “overpopulation.” He was writing at the end of the 18th century, just as the modern rise in population got underway, and believed that population would eventually outstrip food supplies. More recently, Paul Ehrlich (1932-), in a widely-read warning, The Population Bomb (1968), saw the possibility of world famines as early as the 1970s and 1980s. These didn’t happen. World food supplies have increased faster than world population. And famine is a complex phenomenon involving food distribution, poverty and government—it can be persuasively argued, indeed, that there’s never been a famine in a democratic society. But there are limits here. Democratic societies come under increasing strains as population increases. We can expect no significant increases—or at least increases on the same scale as population increases—in the world’s arable lands. Modern agricultural practices already strain agricultural resources, both of soil and water. In developed societies, the degradation of food supplies—in terms of their safety and appeal—has led people toward foodstuffs that are produced by far less intensive (and productive) methods. Even if the world doesn’t experience famine, the food supply, and its health, is likely to become an increasingly difficult issue; catastrophes can’t be ruled out.
An Ideal Population?
What should the world population be? The answer to this question obviously depends on what your ideals are. For example, if you accept current consumption standards as ideal, then the population that the United States can sustain over the long term is perhaps 50 million—about a fifth or a sixth of what it is today. For the earth as a whole, assumptions about what might constitute an “ideal” life would probably include the guarantee of a basic physical life for everyone, basic human rights, and allow for the development of complex, creative societies with diverse cultures that are capable of supporting a high level of science and technology. What would the population of such a world be? It’s obviously hard to say, but estimates usually work backwards from current levels of energy consumption (roughly 13 terrawatts), about two-thirds of which supports the billion or so “rich” earthlings, and project population trends and possible energy conservation against this. If you assume a per capita energy use of 7.5 kilowatts—about the average of “rich” nations today, though only two-thirds of the US level—a world population of 11 billion would mean energy consumption over six times what it is now, and probably certain ecological disaster. On the other hand, if you imagine a drop in the energy consumption of the “rich” nations to 3kw (from about 12kw in the U.S.) and a rise in the consumption of the “poor” nations from about 1kw to 3kw—which is certainly more equable—this would still leave an end-of-century world population of 11 billion consuming twice what is consumed today. On the other hand, a world that used 6 terrawatts, about half of what we use today, would imply a total population of between 1.5 to 2 billion people, roughly the world’s population in 1900-1930: certainly enough to support high level cultures and societies. The exact number is, in any case, not important. What is clear is that both population and consumption must be brought down very sharply. As they fall (supposing they do) a level of population consistent with ecological stability will be found.
How to Lower Population
The levels of population growth that mark “the modern rise in population”—the rise in world population since 1750—were exceptional and clearly unsustainable; and they haven’t been sustained. On a global scale, the peak growth rate came around 1965, and was about 2%; this is now about 1%. In richer countries, the growth rate has already declined to 0.3%. However, in the world’s poorest countries, the rate is still around 2.2% and is not expected to decline even to 1.5% before 2050. Note, by the way, how small these numbers are, at least as percentages. But one of the great discoveries of Malthus was that a population growth rate even very slightly above 0% will, eventually, become exponential, and so it has.
How can world population come down? Population growth (or decline) is always a function of the relationship between the birth rate and death rate: the number of people being born vs the number of people dying. It was a change in this relationship that caused the great “modern” population rise. In Europe before 1750, both birth rates and death rates were high. Since there’s an upper limit to the birth rate (defined by the reproductive capacities of women), the only way the population could have substantially grown was a decline in the death rate; indeed, since the birth rate also began falling sharply toward the end of the nineteenth century, the decline in the death rate had to be particularly steep. Why did the death rate come down?
Of course there are great scholarly arguments about this, relating to the differing contributions of medicine, public health, nutrition, and other factors. Immunization against small pox, improved sanitation in hospitals (Semmelweis told doctors to wash their hands), public sanitation measures that separated sewage and drinking water—so ending cholera epidemics—all played a part. But in all sexually reproducing mammalian populations (i.e., humans) the ultimate level of the population is not simply a function of the birth rate; it’s a function of the number of children born who live to reproduce themselves. If a woman gives birth to ten children (giving the birth rate a boost) but all of her children die before age twelve, the population won’t grow in the long term—whereas a woman who has four children, all of whom live to give her grandchildren, is spurring real population growth. This means that declines in infant and child mortality were particularly important in the “modern rise of population.” Infants and children are susceptible to relatively simple but very common (usually food-borne) diarrheal and enteric diseases. Among poor, malnourished populations these diseases become killers; so it was, above all, rising living standards and improved nutrition—especially the availability of pathogen-free milk—that made children more resistant to them and allowed them to survive…to reproduce themselves. And there’s an ironic wrinkle here: contraception. Contraception became very widespread toward the end of the nineteenth century. Yes, this meant a decline in the birth rate. But fewer children meant that mothers could pay their offspring more attention, keep them cleaner, breast-feed them longer; smaller family size meant higher standards of living, and especially nutrition—so more children survived to reproduce themselves. It’s counter-intuitive, but contraception was a significant factor in the “modern rise of population.”
All of these factors are at work today in countries with higher birth rates and growing populations; and in those African countries with the highest population growth, they are working with a vengeance. These countries have been able to take advantage of the knowledge and the technological advances historically developed in western countries to bring their death rates down sharply and quickly. But fertility rates, for personal and cultural reasons, are more stubborn. (Note: fertility rates measure the number of children born to a woman over her lifetime, while the birth rate measures the number of live births per 1,000 people: so they’re not quite the same. Because birth rates partly depend on the age composition of the population, they’re not quite as good a measure of the present situation.) From 1950 to 2000, fertility rates in Asia and Latin America declined from 5.9 to 2.5 children per woman, but in Africa the decline has been much smaller, from 6.7 to 5.1. Today, Niger is the country with the highest fertility rate (about 7) and the highest birth rate—over 46—in the world. (Right behind Niger are Mali, Burundi, Somalia, Uganda, Bukina Faso, Zambia, Malawi, Angola, and South Sudan; indeed, with the exception of Afghanistan, Yemen, Iraq, Vanuatu, the Solomon Islands and New Guinea, the highest 50 fertility rates in the world are all in Africa.)
How can population growth in these countries be brought down? Since no one wants to increase the death rate, especially of children, the answer lies in declining fertility. And, at least conceptually, the world knows how to do this. Broadly speaking, the answer is “development.” Part of this is economic; economically secure people have fewer children. But even more important are the provision of basic social services, especially health care and education, and especially to women. People will not have fewer children unless they are sure their children will survive, so better health care is essential: declines in child mortality always precede declines in fertility (though reductions in child mortality will, at least temporarily, increase population.) Education is crucial, including education for women. Education allows parents to see a future for their children, and invest in it—in a crude way, quality is chosen over quantity. Education, and a rising level of literacy and culture, also makes contraceptive practices easier to introduce and spread. Even in Niger, women who finish primary school have a fertility rate a little under 7, but those who finish secondary school have a rate below 5. Everywhere, there is a high statistical correlation between more education and lower fertility rates. Both education and health services come together in the provision of contraceptives, which are of course key to bringing down fertility and birth rates. But contraception must always be seen as interrelated with health and education, and especially the provision of these services to women. Countries with high contraceptive use and high infant mortality simply don’t exist; the one always brings down the other…and then reinforces it: where infant mortality declines, contraceptive use rises, and family size goes down because people have confidence that they’ll have descendants. Health services and education, together with access to contraceptives, trump everything, even apparently resistant cultural variables. The Iranian Revolution increased education and access to health care for all Iranians, including women, and today the Iranian fertility rate is lower than the U.S.
The Future of World Population
Anyone who considers the problem of world population and inspects the facts that I’ve outlined in this note can scarcely come away from the exercise with anything less than concern. The world’s population, and its growth, is a human, social, historical problem, and isn’t exempt from other human, social and historical tendencies. A graph of human population growth shows a phenomenon that has “gone ballistic,” and phenomena graphed in this way rarely end well. Yes, it’s possible that human population, having reached some vast number—I’ve used one estimate here; others are larger—might level off and gradually decline. But no one should be surprised if it falls as steeply and rapidly as it went up. Concerned about the economic crisis of 2008, Queen Elizabeth asked the director of research at the London School of Economics, “Why did no one see it coming?” He told the Queen: "At every stage, someone was relying on somebody else and everyone thought they were doing the right thing." And so it is with population—though in the event of a too-precipitous decline there may be no one around for the Queen to complain to.
Many kinds of catastrophe, forced by the enormous and rapid rise of the world’s population, could bring that rise to an abrupt end. Some of these, perhaps, have a science-fiction ring to them, but then 11 billion people is a rather science-fiction number. Various eco-disasters are certainly possible; these could be ones we know about now—global warming, for example—but might equally come out of left field. Disease? This is unlikely: the tendency for pathogens is to attenuate themselves, like scarlet fever. But a widespread social breakdown could easily lead to the spread of ancient enemies, like cholera, on a scale that would overwhelm health facilities. Speaking of ancient enemies, I wouldn’t rule out famine. The world’s seed supply is in the hands of ten large corporations (Monsanto, Dupont, Bayer etc.)—are we quite sure they’re good stewards? And perhaps most likely of all is nuclear war. People are enormously complacent about this problem, barely give it a thought, glibly talking of “regime change” in Russia or “challenging” China in the South Pacific Sea. Nuclear war would rather fittingly reverse a graph that has gone ballistic.
Whether any of these possibilities is realized, it’s worth remembering that the final rise of world population—and the possibility of its decline—will take place in a world that’s defined in quite other ways. From a different angle, this highlights the scope of the problem.
Economic Organization. It’s hard not to observe that “the modern rise of population” coincides with the growth of capitalism. Moreover, capitalism clearly shares some of the characteristics of that rise: growth, and then accelerating growth. Indeed, constantly expanding growth is a characteristic of capitalism; could it survive in the context of a sharply declining population that then stabilized but didn’t grow? There would almost certainly be a different aspect to this: declining consumption. Even today, the world is awash in capital; in a less populated world, with much lower consumption, it’s hard to see the outlets for capital that the system requires. Conceivably, then, a major decline in world population would have to go hand-in-hand with massive changes in the forms and organization of economic activity.
The Nation State World power is now organized along national lines. The pressures that arise from continued population growth, and the problems of bringing that growth down, will be felt differently by different nations. Nations will be competing for increasingly scarce resources; they will find themselves in very different demographic positions. Of course it’s possible to imagine these forces bringing nations together, creating a more integrated and co-operative world. But history is against this; much more likely is competition and conflict.
Lives Lived. By this I simply mean how the experience of over-population enters the ordinary existence of ordinary people. People’s lives are much shorter than the historical processes in which they’re caught up; their reaction is to adapt, cope, get on with it. I suspect that over-population was more thought about thirty years ago than it is now. The American birth rate is actually increasing (though the reasons don’t add up to a baby boom) and there’s definite evidence that among the wealthiest Americans women are having more children: a sign of their affluence. Ultimately, a particular generation (or succession of generations) will likely face, in a severe way, the consequences of over-population. By then it will be too late for any but the most drastic action.
All this means that a declining world population, and then its stabilization, will require extraordinary changes, both to accommodate the amazing levels of population that lie ahead—and, even more, in seeing that level decline. Perhaps the best one can do is to wish all those people—in their billions and billions—good luck.