Professor Joel Cohen (Cohen, 1995), from Rockefeller University, New York, writing in Science, has calculated that between 1860 and 1991, the human population quadrupled. Over that same period, energy usage increased by ninety-three-fold. So the problem isn’t actually the number of people, per se, but rather the amount of energy needed to maintain us in the way that we have become accustomed to.
The per capita energy use is escalating rapidly, exacerbating the problem of a geometric rise in population. And, as resources run low, we must work harder to keep the population elevated. Of course if any kind of large scale disaster should strike, we will be much less resilient to the trauma than if we were living on the ground. Elephants can die of starvation.
The energy flow, upon which we are so reliant, leaves behind some rather unpleasant side-effects. The three greatest causes of extinction at present are global warming, habitat destruction and eutrophication. Each one of these is directly a consequence of our attempts to maintain the human carrying capacity on the planet.
Global warming stems from our use of fossil fuels, in industrial processes, including the Haber-Bosch process, used to produce fertilizers for agriculture, on which some forty percent of the world’s population depends for their very existence. The industrial revolution, hailed by adherents to the Enlightenment philosophy of Hume and Condorcet, has set in motion a technological spiral of consumption.
Habitat destruction is carried out to clear areas for crop plants and animal husbandry. Rainforest in the Amazon, equivalent to the area of France, has been cleared for cattle ranching alone. Swamps are drained and forests felled to convert land for industrialized food production. Habitats are also fragmented by human infrastructure. Meanwhile our desperate need for water leads us to dam rivers and flood areas of important biodiversity.
Eutrophication is a silent killer. Here, the powerful fertilizers used to force the soil into greater productivity, leach out into the water, and horrifically distort natural habitats, leading to huge species loss and the crippling of sustainable ecosystem function.
And so instead of the three horsemen of the Malthusian apocalypse, famine, disease and war, we have introduced these three new destructive characters: global warming, habitat destruction and eutrophication. It is ironic that in our efforts to free ourselves from the original Malthusian checks, we have engineered three equally blood-thirsty killers across the globe.
What have these deadly dragoons, unleashed by humans in pursuit of that utopia, done to our Biosphere? David Woodruff (2001) estimates that current extinction rates are fifty to five hundred times higher than background. The International Union for the Conservation of Nature (IUCN, 2001) reported that over fifty percent of animal species are vulnerable, endangered or critically endangered. A quarter of all mammals, a third of all fish and up to a third of all plants are predicted to face extinction in the next few decades.
Please take the time to read this last paragraph again, slowly and out loud. If there is someone else in the room or on the bus, don’t be put off. They need to hear it. Gary Snyder, writing in 1990, summed up the appropriate reaction powerfully when he wrote “The extinction of species, each one a pilgrim of four billion years of evolution, is an irreversible loss. The ending of the lines of so many creatures with whom we have travelled this far is an occasion of profound sorrow and grief. Death can be accepted and to some degree transformed. But the loss of lineages and all their future young is not something to accept. It must be rigorously and intelligently resisted.”