Future Projections of the Population Curve


Recently, the human population on this planet surpassed an amazing milestone. In the year 2000 it hit 6 billion, and without a sign of slowing down, continue to increase at an unprecedented pace. After taking nearly 3 million years to reach our first 1 billion, it has taken us only 11 years to raise our population the most recent billion (from 5 to 6). This rate of growth can be graphically interpreted as a J-shape pattern. If the past is any indication of the future, this means that while our rate of growth is high right now (a net increase of almost 87 million annually), it will continue increase to no end. But is there a limit to how big the population on Earth can truly be? While many agree on the J-shape population growth of the past, few ascertain that this trend will continue. In the following I will describe some of the current theories about our species' future population growth.

Some ecologists today consider the rate of population growth amongst humans, an ecological crisis. These ecologists see "excessive consumption as an equally important cause of pollution and environmental deterioration."(Southwick, 161) One such ecologist is Charles H. Southwick, author of Global Ecology in Human Perspective. He believes that while some people are "living longer and fuller lives than ever before", a major portion of our population is living in poorer conditions than ever before. (Southwick, 161) Southwick explains that this is largely due to the fact that our planet is already overpopulated and cannot provide enough materials for all humans to share a reasonable standard of living. "A number of scientists believe we cannot, and some believe we cannot ever ensure adequate food supplies."(Southwick, 161) Moreover, it is not just food that we cannot supply for these unfortunate individuals. We also are currently having trouble supplying adequate housing, health care, education, and many other components of a reasonable standard of living. "If we cannot provide these amenities now for 6 billion people in the world, can we expect to provide them for 8 to 10 billion in the 21st century." (Southwick, 161)

On the opposite end of the argument lie optimistic ecologists like Julian Simon. Simon believes that there is no population crisis and no environmental crisis that is due to the rapid growth of humans. He believes, in what many scientists call, a "tech fix". "He asserts that population growth, economic growth, and a resource rich-world coupled with modern technology will produce greater prosperity and better health for increasing numbers of people." (Soutwick, 160) Simon's theory has come true before. For example, when the growth of our human population started to slow during the time of the nomad, humans realized agriculture could support more people, and thus, the Agricultural Revolution took place. In addition, "advances in agricultural and industrial technology have effectively increased the size of the globe over the last two centuries, in terms of the maximum population which it will support." (Dolan, 58) That is to say, a tech fix for 8 billion people down the road might not be as easy, but there are plenty of brilliant minds currently in the world who could ultimately figure out a solution to the problems that an increase in population bring.

Somewhere in between the optimist and pessimist lie the thoughts of Edwin Dolan. Dolan believes that an increase in population will not lead to an ultimate decline in the standard of living of humans. Many ecologists that side with Southwick contend that an increase in population will result in an increase in pollution. To this theory, Dolan replies, "It is true that without pollution control, more population means more pollution…if you want to control pollution, go at it directly, not via a back-door measure of population controls." (Dolan, 69) In short, Dolan believes that humans can decrease overall pollution while still growing in overall population. Humans just have to be more conscientious of the environment and of what they can do to help.

From these three different points of view we can come to three radical conclusions about the current and future growth of our population. Southwick would claim that leading countries, like the United States, need to step in and deter families from having more children. These countries could provided either economic incentives for fewer children "such as better housing for small families and lower taxes for couples having no more than two children", or they could simply provide their citizens with better education about the problems increases in population bring to our world. These governments could also invest in research to improve contraceptives in order to make them "easier, cheaper, safer, and more widely available." (Southwick, 179-180) According to Southwick, if countries like the United States promote such radical political and economic solutions, the rest of the world will realize the problem at hand and follow suit.

Simon and Dolan would claim that no population controls should be put into place. Since Simon believes there will be an eventual tech fix for the rise in population, he might that the government simply has to invest in the private sector to increase research to better the living standard worldwide. Dolan would assert that population and the living standard are to separate topics entirely. Specifically, he would claim that the pollution and the population problem were not correlated if pollution controls by the government were stressed. (Dolan, 69) If the government were to improve pollution controls it would raise the living standard and make the world more hospitable to a larger human population.


1) Dolan, Edwin G. The Economic Strategy for Environmental Crisis. 1974.

2) Southwick, Charles H. Global Ecology in Human Perspective. Oxford University Press, 1996.


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last updated 5/25/03