Can Neuroscience and Darwinism help reframe the population explosion?
By Charles Donelan
According to the United Nations, the world’s population will exceed seven billion for the first time on Halloween 2011, and pundits everywhere are discussing this remarkable achievement in procreation. Some say it’s a wonderful thing; others say we’re all doomed, but everyone agrees about one aspect of the situation: while seven billion may be just a number, the rate of population increase in recent years is astonishing. Although this rate peaked at some point in the 1960s, the world’s human population has been on a remarkable roll in the last half century, adding billion after billion at a record rate. To be more specific, the total has gone from three billion in 1959 to four billion in 1974 to five billion in 1987 and six billion in 1998.
Nothing remotely like this has ever happened before, and a lot of people are wondering what the consequences of sharing the planet with all these people will be. With another three billion predicted on the way in this century, the ensuing demand on the earth’s natural resources may prove unsustainable. After all, the burden of human presence, especially in urban areas, has put a disproportionate and seemingly dangerous strain on resources. Still, societies for many centuries have generally viewed population growth as an unalloyed good—population growth tends to bring power and prosperity with it. Today, this view might seem naïve, but it remains a potent force, especially when it comes in the guise of fundamentalism, whether religious or economic. In other words, if you are among the righteous in the eyes of God or Mammon, then more of your own kind is a blessing, and the unrighteous take up too much food and space.
On the other extreme, there are the neo-Malthusians, those chicken littles for whom the sky is always falling and the population bomb is always about to explode. Thomas Malthus, the eighteenth-century English economist and population theorist, did the world a great service by identifying natural resources necessary for human existence as a salient point in any discussion of population growth, but he also set his cause back by insisting that the constant spread of humanity would only be kept in check by famine, disease, violence, and disaster. Despite the fact that Malthus and many other pessimists like him have been proven false by history, popular accounts of the population explosion continue to repeat Malthus’ characteristic mixture of fear mongering and moral outrage.
In the middle ground between these two stand the sober-minded population scientists of today, who see both promise and peril in the current situation. For instance, Joel E. Cohen, mathematical biologist, argues that humanity’s future depends on three things: access to voluntary contraception, universal education, and adequate food for mothers and children under five. If we manage to achieve these modest goals—which Cohen claims are both mutually reinforcing and globally affordable—our species stands a chance of surviving, despite the population increases of the last fifty years. Without them, increasing population will inevitably mean increasing misery, especially for the more than three billion people internationally who currently live on less than two dollars a day.
“So on the day of eight billion, it’s likely that humans will still be reckless jackasses, even as they become less violent and make room for more people.”
As useful as these statistically based coping strategies may be, they hardly address many of the deeper questions aroused by contemplation of the upcoming day of seven billion. For example, what is driving the steep rate of increase? And how will the changing social circumstances of a dramatically more crowded world affect human behavior in the future? Speculation in these areas finds support elsewhere, primarily in innovative long-range histories of human behavior such as Stephen Pinker’s Better Angels, and in the work of evolutionary biologists such as Melvin Konner and David Dobbs.
For Konner and Dobbs, the rise in population might be explained through reference to a certain propensity towards recklessness in human beings, a kind of “jackass gene” that has kept our species moving out of its comfort zone and into new and unpredictable situations with confidence for millennia. In The Evolution of Childhood, Konner draws on anthropology, neurobiology, and evolutionary theory to paint a panorama of evolutionary advantages all concentrated in, of all things, adolescence. For many reasons that are not immediately apparent, the impulse behind our disproportionate investment in the amusement, distraction, and absurd risk-taking of young adults corresponds with the adaptive behaviors that led to all sorts of crucial breakthroughs in pre-history, from shell fishing to cooking with fire. Without the senseless daring that leads teenagers to drive too fast and skateboard in traffic, no one would have had the nerve to dig up and eat the first clam or roast the first meat.
Still, Stephen Pinker’s assertion that humans have experienced a significant downturn in their level of violence, especially in modern times, would contradict these claims for the efficacy of a jackass gene. But once we apply the logic used by David Dobbs in his recent article on the “Beautiful Brains” of teenagers (National Geographic Maagazine 10/11), it’s possible to set even Pinker’s pacifying progress theory into some kind of larger pattern that’s compatible with the continued elevation of the adolescent attitude in human affairs. If Pinker is right, and humans have become less violent as their population has increased, then the answer is right in front of us—if we look at the data on teens and risk. Apparently, the problem with teenagers is not that they cannot judge risk. In study after study, they perform as well as adults in tests requiring them to assess the riskiness of activities and situations. What makes them such high risk-takers is the way that they respond to social rewards. When there are other teens in the room—or the car—their presence overrides the ordinary calculation of risk/reward ratios, causing teens to seek approval even when the costs may be high.
If the one thing that’s changed the most for human beings in the last fifty years is the relative availability of access to other human beings, then it stands to reason that, given the high value we all put on social recognition, attention, even of the negative kind, is one natural resource we’ll never run out of. So on the day of eight billion, it’s likely that humans will still be reckless jackasses, even as they become less violent and make room for more people.
Charles Donelan is Arts Editor at the Santa Barbara Independent and teaches AP English at the Laguna Blanca School. He writes frequently on a wide variety of topics in the arts, and is the author of A Marketable Vice: Romanticism and Male Fantasy in Byron’s Don Juan (Macmillan).
The views expressed in ecoView are those of the author and are not necessarily those of Ecology Global Network. EGN does not verify the accuracy or science of these articles.



















