The growing human population

“. . . and God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it, and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth...”

For millennia this anthropocentric view of the world from the Bible’s book of Genesis has dominated the attitudes of monotheistic religions and explains, as well as anything, our forthcoming existential plight. 

Over 200 years ago, Thomas Malthus wrote “An Essay on the principle of Population,” which insisted that human population increased in geometric fashion whereas food and other resources grew only in arithmetic progression. The result of this difference, he believed, would be starvation and misery if not somehow corrected. Although food production has grown considerably since 1800 and population growth has been somewhat curtailed by war, famine, disease and natural disaster, Malthus’ theory still remains plausible enough today to affect our thinking.

In 1968, “The Population Bomb” by Anne and Paul Ehrlich predicted that the end of the world was drawing nigh unless humanity significantly changed its ways. The book fueled a good deal of controversy for a few years and was also a major factor in turning people’s attention to better protecting our environment. But the Ehrlich’s thesis seemed too dour; others with the idea that modern technology could cope with an increased population came to prominence and the organization that the Ehrlichs founded, Zero Population Growth, fell out of favor. In 2002, the group changed its name to the more optimistic sounding Population Connection, which continues to this day; but in the half century since “The Population Bomb” was published, world population has more than doubled from 3.6 billion to 7.7 billion.

In 10,000 B.C., world population was less than 4 million people. By 1800, it had increased to about one billion. Since then it has grown more than sevenfold. In 1939, at the start of World War II, world population was still below 2 billion people, but a major cause of the war was Germany’s perceived need for more liebensraum (room for living). Now, 80 years later with nearly four times as many people, population pressures are more severe than ever and continue to grow.

One factor affecting the overall surge in population has been the increase in life expectancy. Since 1970, life expectancy in North America and Europe has increased by nearly 10 years and in the rest of the world on average by more than 15. Most demographers estimate that, barring unprecedented world catastrophe, population will not level off until it reaches at least 11 billion people before the next century. 

Those who believe that we can cope with three or four billion more people are overlooking ecological constraints. Environmental deterioration is accelerating. Global warming is starting to obliterate a significant portion of our most valuable land, our sea coasts. Unless we reverse current trends, in the next 50 years the homes of more than a billion people will be under water. In just the last 60 years, we have destroyed more than a quarter of the world’s rainforests. Flooding, wildfires and desertification continue to reduce arable land throughout the world. We are grossly overfishing the oceans and poisoning our seas with acids and plastic that threaten the food chain. We are exterminating a significant portion of the other creatures that inhabit the planet. Potable water, already scarce in much of the world, is becoming scarcer. We’re even starting to run short of sand.

At the same time, people everywhere including those in developing countries are demanding more creature comforts. Per capita consumption of natural resources, growing since the start of the Industrial Revolution, continues to increase every year. 

Currently, approximately 1.6 million abortions are performed annually in the United States and about 55-60 million worldwide, a surprisingly large number, but only a tiny fraction of 7.7 billion and probably not a major factor in reducing overall world population. However, when women have control over their fertility through education, contraception and improved women’s rights, birth rates inevitably go down.

Our situation becomes more aggravated the more people we add to the world. Some may say that increasing population improves the economy (more jobs, more consumers, etc.), but this is analogous to a Ponzi scheme. Ultimately, growth has limits and it behooves us to work toward a stable situation.

What is the optimum size of the human population? Some have suggested we could accommodate 12 billion people! In “The Population Bomb,” the Ehrlichs recommended fewer than 2 billion (as in the 1930s). But even if we greatly reduce our ecological footprint we may still have to reduce our numbers much below our current level just to survive.

Lakeville architect and landscape designer Mac Gordon writes frequently on environmental matters.