We need a larger population so we will have more geniuses to solve our environmental problems.
Having additional people to work on problems does not necessarily lead to solutions. Consider what happened to the people of Easter Island after this lush, 64-square-mile subtropical Pacific island, some 2,000 miles west of Chile, was colonized by Polynesians some 1,500 years ago. Even as the population soared to around 20,000, all those minds couldn’t solve the tiny island’s resource problems. The large forest of towering palm trees that graced the land was harvested more rapidly than it regenerated. Once they were gone, there was no way to build canoes for porpoise hunting, and without the forest to absorb and meter out rainfall, streams and springs dried up, unprotected soil eroded away, crop yields dropped, and famine struck the once-rich island. Unlike most premodern peoples, the islanders apparently didn’t limit their fertility. Instead, as food supplies became short they switched to cannibalism, which turned out to be an effective-if not very attractive-method of population control. A common curse became, “The flesh of your mother sticks between my teeth.”
Can’t today’s population, with its knowledge of the histories of past civilizations and billions of working minds, help us avoid the fate of the Easter Islanders, and the Henderson Islanders (who completely died out on one of the Pitcairn islands in the South Pacific), the classic Mayans, the Anasazi (Native Americans who built the vast pueblos of Chacon Canyon), and others who destroyed the environmental supports of their societies? We wish the answer were yes. Yet the billions of human minds we have today are not stopping society from destroying its resources even faster than earlier civilizations destroyed theirs.
But that aside, perhaps the larger point is that environmental rather than genetic differences determine what proportion of a population will display genius. It’s very hard to become the next Mozart if one is starving to death on the outskirts of Port-au-Prince. Having more people today is not the solution for generating more geniuses. Creating environments in which the inherent talents of people now disadvantaged-by race or gender discrimination, poverty, or malnutrition-can be fully expressed, is.
Feeding the world’s population is a problem of distribution, not supply.
Of course, if everyone shared food resources equally and no grain were fed to animals, all of humanity could be adequately nourished today. Unfortunately, such scenarios are irrelevant. Although people in developed countries could eat lower on the food chain-that is, by consuming less meat and more grain-and might be willing to make such sacrifices to improve the environment, it is as unrealistic to think we will all suddenly become vegetarian saints as it is to think we will suddenly trade in our cars for bicycles or go to bed at sunset to save energy.
But even if everyone were willing to eat a largely vegetarian diet today, with only a small supplement from fish and range-fed animals, and food were equitably distributed to everyone, today’s harvests could feed about 7 billion such altruistic vegetarians, according to calculations by the Alan Shawn Feinstein World Hunger Program at Brown University and our group, the Center for Conservation Biology, at Stanford. Since the world’s population is nearly 6 billion already, that is hardly a comforting number.
We needn’t worry about future food supplies because scientific breakthroughs (as yet unimagined) will boost grain yields around the world.
Analyses of food-production trends over the past few decades suggest that there certainly is cause to worry about maintaining food supplies. While it is true that the most important indicator of human nutrition, world grain production, has roughly tripled since 1950, what food optimists overlook is that the Green Revolution has already been put in place in most suitable areas, and most of the expected yield gains have been achieved. Consequently, grain production increases have failed to keep up with population growth since 1985, and we’ve seen no productivity gains in absolute terms since 1990. Meanwhile, grain reserves have shrunk severely. A new kit of tools to expand food production is required to carry us into the future, yet no such kit appears to be on the horizon. And even if some unanticipated breakthrough were to be made, it would take years if not decades to develop and deploy new crop varieties-years during which demand would continue rising as the population expanded.