Digest Number 713

--- In spacesettlers@yahoogroups.com, "victoriatangoman"
wrote:

> > >> A sustainable ecosystem, base on Terran life, cannot exist in
a
> space
> > >> settlement smaller than the surface area of a planet.
> > >
> > >With all due respect, there isn't a shred of evidence for this
> view.
> >
> > An understanding of population dynamics in biological systems
> would help to
> > appreciate my point. I'm proposing an Autopoiesis model from
space
> > colonisation, not an Allopoiesis model. Perhaps, therein lies
the
> confusion.
>
> That was very clear from the outset, and was easily deduced from
the
> lines of arguments you were advancing. My input into this point is
> that you're making autopoisis synonymous with sustainable.

To catch my own errors, I meant sustainable over an indeterminate
time. A Habitat's ecosystem may be autonomous and sustainable in
bursts of perhaps years, decades or centuries, who knows, before it
may need to be tweaked or have inputs introduced.

To
> sustain an ecosystem in a Habitat one could involve human
oversight,
> technology, and external resources.

Sorry, I went into automatic rebuttal mode and went too far. The
Habitat ecosystem could control its processes and be self-sustaining
and the human oversight might be a fail-safe mechanism. The
technology could be built into the ecosystem and still comply with
the definition you seek. The introduction of external resources
would clearly be out of bounds within your definition.

It's clear that the larger the Habitat the more complexity we can
introduce into the ecosystem.

BioSpere II made a good run of it considering its limitations. It
was too small in size, too varied in environment, too ambitious in
scope, and a first attempt. Clearly there is more to be learned but
the next experiments should be designed to isolate specific factors
and thoroughly understand them before we try to replicate the whole,
or create a process to mimic the whole.

If this logic doesn't appeal to you you should really lay out your
case of WHY an autopoiesistic system is NECESSARY. To state it is
and offer no support for the assertion is not convincing. To
categorically preclude the possibility of an ecosystem that is
smaller in scale than Earth's requires evidence to support that
position and a rationale why techology and innovation can't overcome
obstacles.

> While an autopoiesistic system is an admirable goal to aim for, it
> is by no means a necessary precursor to Habitat construction.

On further reflection, I'm not even sure that it is an admirable
goal. One of the potential benefits of orbital living might be
ecosystem design. This is impossible on Earth because the sheer
inertia of Earth's ecosystem and the scale of inputs required.

There is nothing inherently "good" about autopoiesis nor anything
inherently "bad" about allopoiesis.

TangoMan