Return to North Glen or Reading List or Credo

(Excerpt from Overshoot: The Ecological Basis of Revolutionary Change by William Catton)

CIRCUMSTANCE: The Age of Exuberance is over, population has already overshot carrying capacity, and prodigal Homo sapiens has drawn down the world's savings deposits.
CONSEQUENCE: All forms of human organization and behavior that are based on the assumption of limitlessness must change to forms that accord with finite limits.

Human communities once relied almost entirely on organic sources of energy—plant fuels and animal musclepower—supplemented very modestly by the equally renewable energy of moving air and flowing water. All of these energy sources were derived from ongoing solar income. As long as man's activities were based on them, this was, as church men said, "world without end." That phrase should never have been construed to mean "world without limit," for supplies can be perpetual without being infinite.
Then the earth's savings, and new ways to use them, began to be discovered. Mankind became committed to the fatal error of supposing that life could thenceforth be lived on a scale and at a pace commensurate with the rate at which treasure was discovered and unearthed. ... what amounted to a "detritus ecosystem." Detritus, or an accumulation of dead organic matter, is nature's own version of ghost acreage.

Detritus ecosystems are not uncommon. When nutrients from decaying autumn leaves on land are carried by runoff from melting snows into a pond, their consumption by algae in the pond may be checked until springtime by the low winter temperatures that keep the algae from growing. When warm weather arrives, the inflow of nutrients may already be largely complete for the year. The algal population, unable to plan ahead, explodes in the halcyon days of spring in an irruption or bloom that soon exhausts the finite legacy of sustenance materials. This algal Age of Exuberance lasts only a few weeks. Long before the seasonal cycle can bring in more detritus, there is a massive die-off of these innocently incautious and exuberant organisms. Their "age of overpopulation" is very brief, and its sequel is swift and inescapable.

When the fossil fuel legacy upon which Homo colossus was going to thrive for a time became seriously depleted, the human niches based on burning that legacy would collapse, just as detritovore niches collapse when the detritus is exhausted. For humans, the social ramifications of that collapse were unpleasant to contemplate. The Great Depression was, as we have seen, a mild preview. Detritus ecosystems flourish and collapse because they lack the life-sustaining biogeochemical circularity of other kinds of ecosystems. They are nature's own version of communities that prosper briefly by the drawdown method.

The phrase "detritus ecosystem" was, of course, not widely familiar. The fact that "bloom" and "crash" cycles were common among organisms that depend on exhaustible accumulations of dead organic matter for their sustenance was not widely known. It is therefore understandable that people welcomed ways of becoming colossal, not recognizing as a kind of detritus the transformed organic remains called "fossil fuels," and not noticing that Homo colossus was in fact a detritovore, subject to the risk of crashing as a consequence of blooming.

Read a much larger extract from "Overshoot"
And there are links to many other seminal writings on the important matters which now face us

Return to North Glen or Reading List or Credo