Skip to Content.
Sympa Menu

permaculture - Re: [permaculture] Lions and elephants on the Great Plains?

permaculture@lists.ibiblio.org

Subject: permaculture

List archive

Chronological Thread  
  • From: Ben Martin Horst <benjamin_horst@myrealbox.com>
  • To: permaculture <permaculture@lists.ibiblio.org>
  • Subject: Re: [permaculture] Lions and elephants on the Great Plains?
  • Date: Thu, 18 Aug 2005 22:02:04 -0700

In regard to "ecological holes:"

The late great evolutionary biologist Stephen J. Gould wrote extensively on "punctuated equilibrium" in biological evolution. In a nutshell, the concept is that the evolutionary process is generally rather slow. Species tend to reach a sort of equilibrium with each other; once in such a balanced state, species change only slowly, if at all. It is only when something unusual happens that the evolutionary process really revs up, before settling back down to equilibrium. The process is a bit like the classical succesion model in a forest after a fire or logging: sudden explosive growth occurs to start healing the land, and eventually new trees grow and the system settles back into equilibrium again. "Ecological holes" are to evolutionary history what a temporary clearing is to an old-growth forest.

Example 1: Undersea volcanoes create a remote chain of islands where open sea existed before. Over the course of a few centuries, the islands are colonized by windblown or floating seeds and by only a few vagrant pigeons and finches, and a few lizards and tortoises that managed to survive the ocean crossing on a lump of driftwood. Once ashore, the plants and animals find a variety of unused niches. They diversify rapidly to fill those niches, and in a matter of a very short time (geologically speaking) their descendents look and act very different from their ancestors and each other. That's more-or-less what happened on Pacific islands like the Hawaiian chain and the Galapagos. The few species that colonized the islands diversified into a wide variety of species unlike anything on the mainland. Darwin's finches all developed different bills to feed on new, unused seeds, and iguanas started swimming around in the ocean and eating seaweed.

Example 2: 65 million years ago, give or take, an asteroid or comet hit what is now the Yucatan. Major ash plumes fanned out across the globe, forest fires ignited on a massive, perhaps global, scale, and giant tsunamis raced across the oceans and penetrated mile upon mile inland. There's argument about whether the impact took out the dinosaurs all by itself or not, but it seems pretty clear that it certainly did major damage to ecosystems across the globe. In any case, most dinosaurs, all pterodactyls and plesiosaurs, and a host of other reptiles and amphibians, to say nothing of plants, all disappear from the fossil record about this time. Ecologies that had remained fairly stable for millions of years were virtually destroyed. Over the next few million years, however, there was an explosive growth in new critters emerging. The few dinosaur survivors filled many of the available aerial niches that the pterosaurs had left (we call them birds today). Mammals, which for millions of years had been little shrew-like beasties, saw an explosion of speciation and diversification. Other plant and animal orders experimented with similar wild and crazy diversification. The same pattern holds true for all of the mass extinctions throughout Earth's history: relatively stable ecosystems are devastated by something (sudden buildup of toxic gases in the atmosphere, catastrophic volcanism, and meteors are among the various causes), countless species go extinct, and the remaining species start picking up the pieces with wild and crazy abandon, developing and diverging into things unimaginable before.

Today we're in the midst of a human-induced mass extinction, and we probably haven't seen the worst of it yet. Whole ecosystems and bioregions are tattered, shattered, or outright destroyed. In the long run, we probably don't need to worry about the ecological survival of the Earth: it has proved remarkably resilient and creative in the past, and it will again. Gaia will play with new assemblages of species and develop plenty of new ones to fill all the gaping holes we've left. The problem for us is that even though the coming burst of ecological creativity and speciation will be speedy in geological terms, it will be unimaginably long in human terms: the hundreds of thousands of years at the least, but more likely four or five million. A little late for Homo sapiens.

As I understand it, that's where permaculture comes in. We use careful observation of ecosystems and our access to many species, both native and non, to begin filling enough of those holes to allow us to survive while Gaia does her work at filling all the rest. If we're successful, the coming millenia might just see not only countless plant and animal species unforeseen to us today, but also a lot of new human species filling a wide range of ecological niches.

PS. "Buffalo Commons" is a phrase that has been around since the mid-70's, as I recall. It was originally a proposal that the US stop subsidizing that intensive cattle-ranching across the Great Plains and turn the majority of it into a national park. The basic rationale is that maintaining "civilization" on the Great Plains is a net loss for the US, at least economically, so it might as well be used for something else, like restoring native ecosystems. A variation on the idea proposed by a few Indigenous activists is to cede these Great Plains territories to an autonomous Indigenous People's state, in exchange for their relinquishment of Native land claims elsewhere (Paiutes from Nevada could give up their claims there and receive inalienable sovereign rights to lands in South Dakota, for example). A google search on the phrase will probably come up with lots of hits. Note that when I use the phrase it's not in support of either of these or any other specific proposal, just an affirmation that it would be a darn good idea to start reintroducing some bison and other decimated native species back to big swaths of their former range.



That's great! Buffaalo Commons could become a new code word for the revitalization of Rural America and, of course, of suburban, wild and urban areas indirectly impacted by such an effort.

The concept of various species naturally causing holes in ecosystems is interesting. On a scale more manageable and less invasive than with herds of sabre-toothed tigers and mastodons, tolerance for and possibly encouraging this to happen within ecosystems, holes fillable by natural selection and succession, or by Man, might be a good thing as increased diversity and randomness might eventually result, as if they were giant edge zones, though not necessarily readily apparent as such.

_______________________________________________
permaculture mailing list
permaculture@lists.ibiblio.org
http://lists.ibiblio.org/mailman/listinfo/permaculture









Archive powered by MHonArc 2.6.24.

Top of Page