Aspects of Global Overpopulation
by Nathan R. Hoot ‘01
Over 6 billion humans currently inhabit our planet, and this figure increases by nearly 80 million every year. In fact, the world population experienced a net increase of approximately 13 people during the last few seconds since you began reading this article. The world population has not always seen such rapid growth – as a species, it took us 123 years to double our numbers from 1 billion to 2 billion, while we spent a mere 12 years increasing from 5 billion to 6 billion. Moreover, current estimates suggest that our population will reach the 7 billion mark by the end of the decade.
Such breakneck proliferation of our species is not due to increased birth rates; in fact, the worldwide fertility rate has been falling in recent times. However, advances in sanitation practices and discoveries in modern medicine have decreased infant mortality while increasing the average human life span. These factors have caused the death rate to decrease even faster than the birth rate, resulting in the population explosion that our planet has experienced in recent history.
While these statistics might be interesting and surprising, how could overpopulation possibly affect us? Thomas Malthus published a work entitled Essay on the Principle of Population in which he noted that the population of any species increases at a geometric rate, while its food supply increases at an arithmetic rate. Thus, the population rises at a rate directly proportional to the current number of inhabitants, but the available food supply continues to grow at an unchanging rate.
In fact, the Malthusian principle has already begun to demonstrate its effects in our world. Sadly, available sustenance is not evenly distributed throughout the planet, so humans living in countries such as ours remain ignorant of the effects of overpopulation. The ideas of Malthus seem so distant and farfetched when we live in a society of plenty, where people can eat their fill and enjoy luxuries. However, depending on how fast you read, approximately 15 to 25 people in the world have died of hunger since you picked up this article. These people are far better qualified than we are to confirm the harsh accuracy of Malthus’ concept.
In a world of limited resources, lack of nourishment represents just one of our concerns. Humans must have places in which to live, so overcrowding looms as another potential future problem. The population density of urban areas steadily increases, while the amount of natural, unused land continues to decrease to meet the demands of a growing population. If population continues to increase at the current rate, then by the year 2750 each human being would theoretically have a mere two-by-two foot patch of land in which to live.
As humans, we are not only numerous, but we tend to be heavy consumers as well. Forest land is being stripped of timber at a terrifying rate, while oil and coal supplies are beginning to dwindle, and industries pollute our fresh water supplies. Our consumption of natural resources must slow in order to avoid exhausting them entirely. Preferably, humans will even be able to leave portions of natural land untouched so that other species might continue to coexist on this planet with us.
The human population seems to be currently experiencing exponential growth. However, biological populations which depend on limited resources for sustenance cannot maintain exponential growth – instead, they exhibit a pattern of logistic growth as resources become exhausted and the population approaches the carrying capacity of its habitat. Unfortunately, estimating the parameters of this logistic growth equation – the approximate capacity of our planet and the rate at which the population is approaching that maximum – would be rather difficult to estimate reliably.
Unless the conditions of our system are dramatically altered, nature will forcibly cause the rate of population growth to slow by some means, because when a population reaches the carrying capacity, the birth rate will equal the death rate. As one possibility, we humans must slow down our birth rate, and modern medical advances such as contraceptives represent a positive step towards this goal, limiting the number of unwanted pregnancies. If we fail to decrease the birth rate, then natural means will cause the death rate to increase to match the birth rate. However, the means which nature will use remain unknown – possibly greater numbers of people will starve to death due to the Malthusian principle, or perhaps overcrowding in cities will lead to increased epidemic disease, reducing our population by that means.
Lastly, one must note that the intention of this article is not to instill pessimism and fear in the reader. Rather, the goal is to inform people, making them aware that as a population, we are rapidly expanding while subsisting on limited means. As an advanced race, our technology originated medicine and amenities to enable us to live longer, and therefore the looming problem of overpopulation is largely due to our own advancements. However, such an innovative population holds the potential to use this same technology to remedy the problem that it created – perhaps we will develop new forms of engineering and architecture to create efficient living space, while advances in agriculture might enable us to greatly increase our available food supply, and new forms of manufacturing and consumption could help us to use natural resources more effectively, allowing us to coexist peacefully with rugged, untouched land and wild species.
For the time being, no one knows what the future holds. As we face the unknown, we must remember that we are not merely a species whose numbers must be "culled down." Rather, every inhabitant of this planet, as well as every new child that is added to our world, is a fellow human being – somebody’s son, somebody’s sister, somebody’s friend. As long as the more fortunate people work to serve those who have less, our future remains bright. Life was never meant to be easy, so we must remember – the glory of man is not in the success, but in the struggle.