Avoiding the Crowds: Overpopulation and Its Impact on the Environment

Kristen Traband


Technology has allowed the human population to grow exponentially over the last millennium. Advances in travel, medicine, and quality of life have allowed human beings to spread to all corners of the globe, to take advantage of the Earth’s abundant resources, and to lead longer and more fulfilling lives. Human beings are the Earth’s dominant species, and we have developed the ability to manipulate our environment to meet our needs and desires; our exploding population is an illustration of this dominance. As the human population grows, however, problems are arising. Concerns about the way in which human beings negatively impact the environment have been raised, and many people are wondering just how big of a human population the Earth can possibly sustain. As time goes by, it is becoming more and more apparent that if humanity wishes to continue to live comfortably and retain our position at the top of the food chain, then we will have to find some kind of homeostasis at which both humanity and the environment can coexist.

The first question to address on the issue of population growth is whether the human population is indeed growing; while most demographers suggest that the human population will continue to grow at an alarming rate, other calculations point in the opposite direction. A 2003 United Nations report assumed the world fertility rate to be 1.85, meaning that number of children born per woman across the world is, on average, 1.85 (Wattenberg). Over time, this fertility rate would lead to a population decline, as the fertility rate needed to sustain the current population is 2.0 or 2.1 (for every two people that procreate, their two children replace them; the 0.1 accounts for children who may die before they are able to reproduce). While this report claims that the population, will, in time, begin to decline, other calculations project that the human population will continue to grow at alarming rate. Some demographic statistics have shown that the world population is growing at a rate of 1.5 percent, and project that by the year 2020 the world population, currently approximately 6.6 billion, will top 8 billion (Southwick 159). While these population statistics seem to contradict one another, it may be possible to understand population growth in terms of which populations are growing: in more developed countries, the fertility rate has declined, and is on average less than the 2.1 necessary for sustainability. In Europe, the fertility rate is around 1.4; in Japan, it is around 1.3. In less developed nations, conversely, the fertility rate is greater than 2.1, and averages to approximately 2.9 (Wattenberg). Because less developed nations, which include India and China, house the majority of the world population, this could explain the growing population. It also means that in the next few decades, more and more of the Earth’s population will be in poor or developing nations, a development that has the ability to greatly affect the rest of the world.

If we assume that the world population will continue to increase, as most demographers do, the implications of this population explosion are serious. Because we do not know the “tipping point” at which the Earth cannot sustain any more human beings, it is possible that we will unknowingly pass this point and suffer the consequences of overpopulation. The Earth’s resources, already stressed by overuse, could very well dry up, leaving billions of people without food, sources of energy, or a number of other commodities. Increased levels of disease may also occur due to overcrowding in cities, as well as a lack of clean drinking water. As more and more land becomes occupied, more and more disputes may also arise, and nations may go to war with one another to protect their precious property. Global warming, an ill that has already had an impact on the Earth, would undoubtedly become worse as there are more and more energy consuming people inhabiting the Earth. Overpopulation will undoubtedly have negative consequences on the Earth and those that inhabit it.


There are a number of theories detailing how the population may reach a state of equilibrium, even if humans do nothing to proactively change the circumstances. Developed by T.R. Malthus, the Malthusian theory, or “dismal theorem” explains that as the population grows, the poorest classes will be the most adversely affected. The rising cost of living will cause population growth to cease among the most disadvantaged classes, and while the population will continue to grow among the upper classes, members of the lower-middle class will be pushed below the subsistence level in order to make room at the top. This will result in excess deaths among the destitute and excess births among the prosperous until the population eventually levels out (Dolan 59). There is a reason why this projection is known as the “dismal theorem;” the picture it paints of overpopulated society is certainly not pleasant, especially for those who are in the lower classes. If human beings do not seek to alter the course that increasing population is taking us down, it seems as though we are doomed for a fate like the one outline by Malthus.

There are ways in which the population can be effectively controlled, although many are controversial. One suggestion is to make birth control more readily available for people living in less developed countries. This is a contested solution however, as the culture of many developing nations strictly prohibits contraceptives. In the Philippines, for example, women are banned from using birth control by their Catholic faith. While birth control may be an option in some countries, it would not be the most viable option in others. Another suggestion is to limit the number of children a family may have, which would also raise objections. Many people feel as though it is the right of every man and woman to decide how many children they wish to have, and that putting a cap on the number of children each woman may bear would be a serious infringement on human rights. The only acceptable option seems to be educating people around the world about the dangers of overpopulation, and hoping that their increased awareness will help to slow population growth. Still, it will be a tough task to convince families dependent on the labor of their children to run the family farm or work at the company business that they must save the planet by not having more than 2.1, or maybe even less, children. With more immediate concerns and hardship facing citizens of developing nations, it seems as though population control in these countries will be a hard battle to win.

Most demographers agree that population growth will continue to increase over the next few decades, and that the Earth will become precariously close to overpopulation. The dangers of overpopulation are real and imminent, and we could see the effects in as little time as the span of our own lives. Like many issues that plague the relationship between human beings and the environment, we must confront the problems we are causing and develop effective solutions or the fragile balance of life on Earth will undoubtedly be upset.



Dolan, Edwin G. TANSTAAFL: The Economic Strategy for Environmental Crisis. New York: Holt, Rinehart and Winston, Inc., 1974.

Southwick, Charles H. Global Ecology in Human Perspective. Oxford: Oxford Univ. Press, 1996.

Wattenberg, Ben J. “It Will Be A Smaller World After All.” The New York Times. March 8, 2003.

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last updated 04/15/08