Re: Alien bacteria and biosphere II

[David@interworld.com (David Levine)]

Timothy van der Linden wrote:
> 
> >>By the way, I note there is concern about alien biologies
> >>overwhelming our biologies.  I think it depends upon how
> >>advanced the "exo-bacteria" are.  There is also the
> >>possibility of OUR bacteria completely overwhelming the
> >>local ecosystem.  This is, of course, undesirable.  But
> >>not dangerous to us.
> >
> >I supposed we havn't been talking about the Earth plague risk much.  Nasty
> >environmental impact stament.  "Ah, well we could whipe out an entire
> >planetary ecosphere."   F.O.E. would nuck NASA as a premtive strike!
> 
> Yes, if we have bad luck the planet will be rotting away after a few years.
> 
> >I don't really think the risks are due to sophistication of bacteria.  Just
> >the fact they might each be about the same level of sophistication, but
> >inconpatable with the evolved checks and balences of the other ecology.
> >Sort of like how Kudzu and fire ants (remember them Dave? ;) ) are taking
> >over the southeastern U.S.  They arn't better or worse, but different
> >enough to not have a effective local opponent.
> 
> Even if they are less sophisticated, the hazard of killing us is possible,
> just because we have evolved beyond them too far.

Yes, the worst possible scenario: they kill us off, and we
kill them off.

Of course, this assumes that alien life would be based off
of DNA.  I assume it will be - but I suppose there could
conceivably be other structures which could self-replicate,
compact themselves, and do all of the other things DNA
does...

If alien life ISN'T based on DNA, it would be unlikely that
biocontamination would occur in either direction.  Chemical
reactions (i.e. allergies, as someone - - Kelly? - - noted
earlier) would be the biggest problem...

David