Humans are diverse and complicated beings. When I was in high school biology class we learned that bacteria, placed in a petri dish with an ample supply of food, would multiply until either the food ran out or they polluted their little environment so badly that their numbers fell back to be equal to or below their original population. Eventually, without additional food input, they would all die. This model, while instructive, is an extremely simplistic model of life on earth. Unlike the bacteria we have constant energy input from the sun and a wealth of mineral and energy resources which will sustain us and the other life forms for a long time to come, though how many of us will be sustained will vary, and the out-of-control increase in population we are currently experiencing is, by far, our biggest challenge yet.
Human diversity and the complexity of the global economy present non-catastrophic options. As we climb the steep curve of the population explosion we get a clearer view of the events and changes that will occur as population reaches a peak and we begin the journey down the other side of the curve. Many of us often think about the possible (probable) calamities that will reduce our population – wars, epidemics, and famine. Natural and man-made disasters in recent times have not made much difference to the global population, however. We also don’t often think about the less disastrous scenarios that could occur, perhaps because in the media the “doom and gloom” stories bring more attention, higher ratings, and better sales. From movies, books, and documentaries about planetary-scale disasters, written from both scientific and purely fictional angles, it is clear our society is more and more fixated on apocalyptic events, but reality is rarely so extreme, and recent events of huge size have still made virtually no dent in world population. What kind of changes are we already seeing that do not involve specific disasters and yet have real potential to measurably reduce population?
Birth rates have already been declining in both developed and developing countries. As standards of living and education rise in a country, and infant mortality declines, family sizes also tend to decline. More educated citizens may delay or avoid having offspring, or decide to have fewer children, as they gain an understanding of the population problem we are facing. People less worried about having children around to take care of them in their old age also have fewer children. India, one of the most populated and fastest growing countries is now making serious efforts to reduce their birthrate using a variety of approaches. Individual governments may make policies to attempt to increase or decrease their birth rates, but such measures rarely have a big effect compared with educational and economic influences. Inevitably birthrates will fall below replacement level and stay that way for at least one or two generations, and the sooner that condition is achieved the more time we will have to address the overpopulation problem, and the better the chance our children and grandchildren will have of living good lives.
Declining birth rates are becoming increasingly prevalent in many countries due to economic decline. Recent research on population changes in the U.S. during the current global recession have revealed that, as people are less economically well off they hold off on having children and have fewer children just to cope with declining income and standard of living. Regions seeing larger economic declines also experience greater declines in birth rates as people recognize that they can’t afford the extra “mouths”.
Larger scale disasters, natural and man made, will occur as there are more people to be harmed. If the population was still small in, for example, Bangladesh, there would not be the population pressure that has pushed millions into living just feet above sea level in the country, which is mostly river delta. A cyclone moving into this area easily endangers millions of people. Recent flooding in Pakistan, in which many people are physically out of reach of rescue and aid efforts, also shows how disasters will worse in human terms because there are a lot more people affected. Similarly, while it wouldn’t seem reasonable to live in an area both below sea level and directly adjacent to the largest river on the continent, tens of thousands of people were doing just that in New Orleans when hurricane Katrina hit, and the economy of the region still hasn’t recovered. Long and wide-ranging economic effects of such disasters will reduce birthrates and this may eventually mitigate the population problem to some extent.
Overpopulation itself will indirectly lead to man made disasters that will, in turn, depress economies and motivate smaller families. The Deep Water Horizon disaster is a clear example of this. There was a time when drilling such oil wells was not technically feasible, but the needed technology was developed to satisfy the growing demand for energy, and fossil fuel was still cheaper to obtain than other types even at the radically higher cost of drilling such wells. The economic impact went far beyond the people who worked in the fishing and oil industries of the Gulf, proving that, as we pursue increasingly risky methods required by less and less accessible resources the accidents will become bigger and more devastating and the effects more widespread. The blockage of any of the handful of shipping channels through which major proportions of the world’s oil and gas are shipped could cause large price increases and serious economic problems for large populations who depend on those commodities. The economic effects will increase faster than the scale of these types of disasters, and could reach global proportions, creating or exacerbating worldwide recessions. As we’ve seen, however, birth rates will be reduced during these recessions. Eventually, overlapping disasters could lead to a decades-long recession that persists until we are years into the down-side of the population spike.
Can average humans learn and understand enough to mitigate the negative effects of the population explosion? In the early 1970’s, seeing the population explosion already in motion, I made the personal decision not to have children. I was not alone then, and even more people are making a similar decision now based on a growing understanding of the population problem. It remains to be seen how much effect this will have on the challenges we will face resulting directly and indirectly from overpopulation, but the net effect will be similar to that of conservation efforts: it will buy time for more education and innovation, and increased efforts to reduce birthrates, energy consumption rates, and total pollution of the environment as we muddle our way towards a sustainable situation.
In the end, at a sustainable and stable level, countries’ birth rates will hover near replacement levels. The average global birth rate must inevitably move towards a no-growth, strictly-replacement level. Population movements will continue to be driven by economic differences as demand for workers in the below-replacement level countries will drive higher levels of compensation and attract workers from other countries, especially those whose birth rates are above replacement levels or have lower standards of living. A sustainable population will most likely be somewhere in the middle of demographers and other scientists’ predictions. While some predict that, with innovations in food production, energy conservation, and other areas, the earth could sustain 10 billion humans, I seriously doubt that is possible without the large scale commercialization of some new energy technology like fusion power, and possibly not even then. On the other hand, to think that the human population would be nearly wiped out is unrealistic as well. Given the uncertainties around future energy supplies and other conditions, it is possible that sustainability could be achieved at a level of a billion people or so with our current technologies. Members of the current population spike will live for decades, and that means life expectancies could drop precipitously and death rates could soar in the latter half of the 21st century, but no solution to this seems forthcoming.
The most likely scenario includes repeated and/or long running economic recession, and redefinition of the term “growth”. Adjusting the population downward will mean a big paradigm shift from the current concept of “growth” as necessary to economic health, and it is possible that the term “growth” will be re-defined to mean growth in technology, improvement in average levels of education, increase in intellectual productivity, and other measures of quality as opposed to quantity.
In any event, awareness of the population explosion, long-range plans, and focused mitigation efforts are increasing, but more is needed today. If we are to avoid or minimize the impact of the doom and gloom scenarios many are predicting we need concerted efforts to increase awareness, improve education and increase innovation, and reach a global understanding and agreement on this problem. This is the biggest challenge humanity has ever faced. Whether we are up to the challenge remains to be seen, but it requires our best and most constant efforts today and every day. Please communicate with your government representatives and anyone else to increase our communal understanding of this huge problem, do what you can in your personal life to address any aspect of the problem, and help everyone understand how our energy, pollution, immigration, and a host of other problems are directly traceable back to overpopulation. Give people a message of hope, but a message conditioned on taking serious action now. The clock is running and the population explosion is already here, with the big spike soon to come. Our efforts will determine how well our children and grandchildren will do, and may define their ultimate survival.
As always, I welcome your comments. — Tim