Population

Overpopulation: Why ingenuity alone won’t save us

We are running out of tricks to squeeze more from a planet already bursting its seams.

Children at Dadaab receive a supplemental meal in an effort to give them caloric intake they need to grow and survive. (Los Angeles Times)

It’s easy to grasp that in a national park, balance must be maintained between predators and prey, lest the ecosystem crash. But when we’re talking about our own species, it gets harder. The notion that there are limits to how much humanity this parkland called Earth can bear doesn’t sit easy with us.

The “nature” part of human nature includes making more copies of ourselves, to ensure our genetic and cultural survival. As that instinct comes in handy for building mighty nations and dominant religions, we’ve set about filling the Earth, rarely worrying that it might one day overfill. Even after population quadrupled in the 20th century, placing unprecedented stress on the planet, it’s hard for some to accept that there might be too many of us for our own good.

A recent essay in the New York Times by University of Maryland geographer Erle C. Ellis, argued that population growth is actually the mother of invention, that it inspires new technologies to sustain ever more humans and to coax more from the land. And as Pope Benedict XVI wrote in his 2009 encyclical “Caritas in Veritate,” “On this Earth there is room for everyone … through hard work and creativity.”

In 2011, I visited the Vatican’s Pontifical Academy of Sciences, which had warned in 1994 that it was “unthinkable to sustain indefinitely a birthrate beyond 2.3 children per couple…. The contrary demographic consequences would be unsustainable to the point of absurdity.” Nevertheless, the church still encouraged population growth.

With a billion humans already malnourished, I asked the academy’s director where would we get food for nearly 10 billion by midcentury? Clearing more forests for farming would be disastrous. Beset by floods and erosion, China alone has been spending $40 billion to put trees back. And force-feeding crops with chemistry has backfired on us, with nitrogen runoff that fouls rivers, deadens New Jersey-sized chunks of the oceans and emits large quantities of two greenhouse gases: carbon dioxide and nitrous oxide.

The answer, I was told, would be through increased yields using new genetically modified crops from the centers of the Green Revolution: the International Maize and Wheat Improvement Center in Texcoco, Mexico, and the International Rice Research Institute in the Philippines.

The Green Revolution’s high-yield, genetically selected strains more than doubled grain harvests during the 1960s. It is often cited as having triumphed over dire predictions of famines caused by population growth outpacing food production, which were famously made by economist Thomas Robert Malthus in “An Essay on the Principle of Population” and echoed by his latter-day analogues, Paul and Anne Ehrlich, who wrote “The Population Bomb.”

However, when I went to the maize center in Texcoco and to the rice institute in the Philippines, I found no food scientists who agreed with that triumphalist scenario. Instead, I learned, Green Revolution founder Norman Borlaug had warned in his 1970 Nobel Peace Prize acceptance speech that his work essentially had only bought the world time to resolve overpopulation.

Read more at the Los Angeles Times

Overpopulation Is Not the Problem? Really? | Robert Walker published 9-18-2013

Last week, the New York Times published an opinion piece titled, “Overpopulation is Not the Problem.” Written by Erle C. Ellis, an associate professor of geography and environmental systems at the University of Maryland, the column dismisses as “nonsense” concerns that, “… by transforming the earth’s natural landscapes, we are undermining the very life support systems that sustain us.”

Wow. That’s a relief. When scientists around the world are warning that humanity is in danger of exceeding “planetary boundaries” and causing irreparable harm to the environment and its ability to sustain existing life forms, including human life, it is refreshing — in the extreme — to hear that we have nothing to worry about.

While acknowledging that we live on a finite planet with finite resources, Ellis insists that there “is no such thing as a human carrying capacity.” Other species on this planet suffer massive die-offs when their numbers exceed what nature can sustainably provide, but modern humans, according to Ellis, are an exception to that rule. Humans, in his words, do not have to “live within the natural environmental limits of our planet.”

In support of that bold proposition, he notes that at numerous times in the past 200,000 years humans have altered the natural environment so as to increase the carrying capacity for our species. When we hunted large animals to near extinction, we found ways to hunt and consume smaller species. When our hunter-gather lifestyles did not produce enough food, we domesticated animals and began growing crops. When traditional farming was not producing enough, we manufactured fertilizer and began irrigating our crops. And because we expanded our carrying capacity in the past, we can do so again in the future.

However, as anyone on Wall Street will tell you, past performance does not guarantee future results. The fact that a value of a stock has doubled or tripled in the past does not mean that it can go on doubling or tripling on into the future. In nature, as in the financial world, there are limits to exponential growth on a finite planet. Sooner or later, what goes up ultimately comes down. And many times it comes down with a crash or a bang. Bubbles burst.