permaculture

[John Schinnerer <eco_living@yahoo.com>]

Aloha,

> Theory sort of 
> requires that they stop multiplying when they've reached equilibrium
> with their food source.

No, actually, many (most?) species will go well past equilibrium on
their initial feeding/reproducing binge, then 'crash' (humans not
excepted).  If they've displaced previous species while doing so and
are quicker to recover, they'll continue to dominate if food supply can
recover.

Over a large time scale this cycle of crash and recovery will look like
something we might call "equilibrium," and the cycles may become less
extreme/very mellow over time.  On shorter time scales it will look
like population explosion/food source decimation/food source recovery;
repeat; repeat;....

Species will not only go past long-term equilibrium in the short term;
they may also push their food sources into crashing mode as well.  That
is, by the time the species population starts to crash from lack of
food, the food they eat (or resources it requires to survive) has been
so depleted that it may not recover, or at least not recover "quickly
enough" for the species to also survive - especially if there are other
faster-moving species waiting for space and time to spread.

I doubt that what they do in one ecosystem can be any certain or
necessarily even useful indication of what they'll do in another
ecosystem (not according to permaculture ways of thinking, anyhow -
complex systems, many many many variables, etc.) - and, I'd err on the
side of caution, looking at the worst consequences in one place as at
least possible in another.  


=====
John Schinnerer, MA
-------------------------
- Eco-Living -
Cultural & Ecological Designing
People - Place - Learning - Integration
john@eco-living.net
http://eco-living.net

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