If we listen to the news out of Washington, we may think that the gravest threat to humanity comes out of Syria, or maybe this week it's Iraq. The global "terrorist threat" is a red herring, a distraction, an excuse for war, repression, and domestic spying. But that doesn't mean that there are no real threats to our future. The biggest may be human numbers, combined with the capitalist life style, based on profligate consumption. There are two good reasons to throw yourself into a global movement for environmental sanity. One is reconnection to nature, to people, to your own soul. The other is that everything we hold dear may depend upon it.
Before we learned empathy, before we learned to share and to wait our turn, before we learned to provide for others and to trust that our needs would be provided in turn--we were Terrible Two-year-olds. Everything was me, my and mine.
Before humanity, Gaia was a diverse and wondrous beast, a many-headed Hydra, with different local faces in mountain and forest and desert and ocean environments, every acre a unique ecosystem.
Henry David Thoreau spoke of teaching the earth to say "beans" instead of "grass" -- "this was my daily work." The history of humanity on this planet has been to divert the Earth's primary productivity from the diverse cycles and epicycles in the tangled bank that is nature, to align the primary productivity in the service of man, to feed and clothe and house us, to provide our comfort and transportation and amusement.
As humans spread out of Africa some 60,000 (or was it 200,000?) years ago, every place that we appeared, the charismatic megafauna would disappear, and humans would replace them at the top of the food chain. Giant bears in Europe, Giant Sloths in South America, Mastodons and Sabre Tooth Tigers in North America, Great Awks in Iceland, 7-foot Kangaroos and 3-ton Wombats in Australia, 8-foot Moas in New Zealand (the original Big Bird). All the largest animals that thought they were safe from predation succumbed to the chiseled flint spearheads and the clever tricks and traps of small bands of humans. Ecosystems were made over in our service.
For thousands of years, we humans thought only of me, my and mine. We understood that as we domesticated the planet there would be victims. There are winners and losers in the game of life. It is our mission, our destiny to make sure we are among the former.
Recent centuries have seen an acceleration of this process, impressive increases in the conversion of grass to beans. Hunting and gathering yielded to agriculture, then factory farms. Monoculture has replaced the tangled bank. Greater triumphs for humanity, greater losses for the lower plants and animals that we displace.
We all live in artificial environments, "Little we see in nature that is ours," wrote Wordsworth over 200 years ago, and I daresay he never saw Walmarts or even Manhattan. We take a moment to remember the plight of the dying birds and the frogs, the poor frogs -- the world's amphibian populations have been disappearing at the rate of more than 3% per year. We miss nature, we truly do, but we imagine all the same that their loss is our gain. Man is no longer dependent on the ecosystem that birthed us. We can live in an engineered world. We will cover the Earth with farms and factories and housing, and human life will go on, even if what we know as Nature is dead as a Dodo.
What if it isn't true? What if human life is more dependent on a functioning ecosystem than is apparent? We are already coping with a precipitous decline in pollinating insects by renting out mobile beehives to our farmlands. We don't really know to what extent our farms are dependent on the ambient ecology. Bacterial communities recycle carcasses into nutrients. Wetland ecologies purify water. Oceans buffer our atmosphere.
California grows half of the produce consumed in the United States, and continues to do so by mining a fossil water table which is down 40 feet in the last 40 years. The American Midwest is the breadbasket not just for the US of A, but for much of the world; and there a rich layer of topsoil, laid down over tens of thousands of years, is being washed into the Mississippi in a few decades.
Putting a dollar value on "ecosystem services" may be an absurdity, but here is a study that sought to catalog some of the value of Nature, and stopped when they got to a number that was twice the economic output of the entire world.
We don't know how much we can grow or how many people we can support on this planet sustainably, because we've never tried. But there has been one small-scale experiment that may be instructive. In the late 1980s, visionary scientists constructed Biosophere II [link] in the Arizona desert. It was conceived as a self-contained microcosm of Planet Earth (re-named "Biosophere I"), complete with farmlands, forest, wetlands, a desert, a miniature ocean with coral reef and a tropical jungle modeled on the Amazon -- all in an enclosed dome that covered 3 acres. The biological community was engineered to be a closed, self-sufficient artificial ecosystem, recycling oxygen with its plants and purifying water in its wetlands. There was solar energy aplenty.