Our overcrowded planet is struggling to cope


If we are to survive, we must ensure our human footprint does not exceed the capacity of the planet to support us.

You go to the doctor with severe pain in your abdomen. You want her to give you something for your pain, but you also want her to figure out what is wrong. In personal health care, each of us wants to alleviate the symptoms and cure the cause of our illnesses.

All too often in modern society we are content to address symptoms and then ignore the causes of our problems. Increasingly, the cause behind global problems is continuing growth in the human population. It is time to take reducing population growth seriously.

In my lifetime, human numbers have more than doubled, from 2.5 billion people to more than 6 billion people. This growth is without precedent in human history. The litany of challenges directly attributable to this growth is staggering.

For example, governments may have bungled the response to hurricane Katrina, but the causes of the disaster are clear. More humans on Earth burning more fossil fuels alter atmospheric chemistry. Consensus among climate scientists is that this alteration contributes to increasing intensity and numbers of tropical storms. Also, more people living in America means more people living in places vulnerable to natural disasters, like the Gulf Coast.

Outside of the Gulf Coast, no matter how good our disaster relief may be, more people mean more wildfires, more floods, more mudslides, more floods. Witness deaths in the Philippines from mudslides or, in Kashmir, from earthquakes. Globally, many more people now live in places vulnerable to natural disasters. We could avoid living in those places when there were fewer of us.

Illegal immigration to the United States results in calls for a “big fence” between the United States and Mexico, or calling out the National Guard to bolster the Border Patrol. Rapid population growth in Mexico and Central America degrades rural resources, causing desperate people to migrate. No fence or cadres of the Guard will stop the pressure this population growth places on America.

Tropical forests are destroyed in South Asia and South America. More people mean growing global demand for wood fibers from these resources. At the same time, growing poor populations resort to slash-and-burn agriculture for survival in the same forests. More people, more deforestation.

Conservation biologists believe extinctions of plant and animal species are increasing at unprecedented rates. The root cause: growing human numbers. To have space to grow food or build shelters, humans crowd out animals from their natural habitats. Poor people see those very same animals as food resources. Rapidly growing human populations mean fewer resources for other species.

Even rising energy prices are an artifact of growing human numbers and increasing industrialization. The rapidly growing demand for oil from 1.2 billion Chinese, mimicking high energy use in developed countries, means we all will have to pay more for energy.

Suburban sprawl and wildland subdivision, declining ocean fish stocks, increasing threats of global influenza pandemics, African civil wars, traffic congestion, air and water pollution, groundwater depletion, solid waste disposal problems – the list of problems for which population growth is the cause goes on.

There are strategies to address the symptoms of these problems, but those are only quick fixes, the global equivalent of an aspirin to treat serious illness. Until we address the root cause, these problems are only going to grow. The root cause is human population growth.

Of course we know that populations cannot continue to increase forever. Various experts project the population to have peaked by 2050 at about 7.5 billion, or to have reached 10.5 billion by that point and be still growing. The assumptions behind the different projections are unprovable. The key point is that we cannot afford to leave the outcome to chance. Chance leaves us simply hoping for benign population futures while fearing catastrophic outcomes. The alternative is to take control, to make sure to the best of our abilities that the human footprint does not exceed the capacity of the planet to support us.

We know how to address the problem. But the how does not matter until we recognize the absolute necessity of ending population growth. It is in all of our interests to start sooner rather than later.

Mark W. Anderson is the coordinator of the ecology and environmental sciences program at the University of Maine.