[meteorite-list] Panspermia and Mars back contamination

[Mexicodoug]

"Pathogens and their hosts are, quite literally, made for each other."

I understand this statement but disagree with it in the terms of the 
current debate. It presupposes our thoughts from our experience with 
life on earth and the equilibrium life has here. At a basic level we 
are just bags of sugars, proteins and fats. Detritus on earth can be 
eaten by millions of organisms - just about any organic materials and 
then there are even critters that can deal with sulfur and nitrogen 
bases in extreme environments.

How many microorganisms can live in detrital composts on Earth? What 
prevents them from eating organisms that are alive? It is more a one 
way protection developed by the living host in this convergence, but 
not necessarily a handicap for the invasive. If the host had no basis 
for an immune response, microorganisms would eat people alive just as 
easily as detritus on Earth, like the massacre that happened during the 
Spanish Conquest of Native America.

I guess the question you might raise is: But if Martian microbes had 
nothing like flesh to eat how would they suddenly become human 
flesh-eating nanobacteria or whatever, here? Given the harsh Martian 
environment they ought to be fairly omnivore and if we are presupposing 
some kind of cellular life (this being subject to another debate) I 
don't see it as far fetched. Really, if the "Martian pathogen" found 
anything at all to eat on the smorgasbord of
 earth it could trash our 
ecosystem by hitting any level of our equilibrium without being harmful 
at all directly to humans. It might even be passive and like our oceans 
and be super-photosynthetic, and as an example peacefully co-exist 
except for non-stop peeing of cyanide or something such, into the 
oceans...a la movie Sunshine (2007), the greenhouse in the Icarus 1.

Best wishes,
Doug

PS, the good thing is ... scientists, instead of our immune systems, 
probably could devise treatments fairly easily, pretty much due to the 
absence of "being made for each other" (= able to fight back via 
convergent evolution) cited.


-----Original Message-----
From: Chris Peterson <clp at alumni.caltech.edu>
To: meteorite-list at meteoritecentral.com
Sent: Sat, 6 Jun 2009 1:05 am
Subject: Re: [meteorite-list] Panspermia and Mars back contamination


>The whole fear that return samples from Mars, either 
>by robotic mission or manned, seems thoroughly irrational to me. 
 
I think that's a little extreme, but I certainly agree with you that 
any life on Mars is very unlikely to be pathogenic. On Earth, only a 
tiny percentage of microbes are pathogens, and the majority of those 
have evolved as such in concert with our own evolution. Pathogens and 
their hosts are, quite literally, made for each other. 
 
Still, some microbes are incredibly hardy, and the potential that 
something from either planet might become an invasive=2
0species on the 
other (with unknown environmental consequences) should at least be 
taken into consideration when designing missions. If nothing else, any 
cross contamination could thoroughly ruin the quality of science that 
can be performed. 
 
Chris 
 
***************************************** 
Chris L Peterson 
Cloudbait Observatory 
http://www.cloudbait.com 
 
----- Original Message ----- From: "Rob McCafferty" 
<rob_mccafferty at yahoo.com> 
To: <meteorite-list at meteoritecentral.com> 
Sent: Friday, June 05, 2009 5:38 PM 
Subject: Re: [meteorite-list] Panspermia and Mars back contamination 
 
> 
> On a more realistic note...(though I applaud the jocularity) 
> 
> The whole fear that return samples from Mars, either by robotic 
mission or > manned, seems thoroughly irrational to me. 
> 
> The very idea that a microbe that MAY exist on present day Mars that 
will > have spent 3 Aeons adapting to a cold, dry, low atmospheric 
pressure, slow > metabolic existence would thrive inside a human body 
seems, frankly > ludicrous. 
> 
> On earth, extremophiles can only exist in their own little niches 
because > once they are out of them, they either die from conditions or 
competition > from better adapted organisms. 
> 
> Given the opportunity to go to Mars, I'd be there like a shot and I'd 
take > my chances. 
> 
> As for Greg's Martian Champagne. I20can't help feeling we have an idea 
for > the latest "trendy" craze to part overpaid footballers (soccer 
players) > from their cash. 
> I reckon you could get these self centred egotists to pay £300 ($500) 
for > a glass of "Rock Rose" or "Selene Rum" (registered trade marks, 
patent > pending) as they attempt to impress their friends/one night 
stands and > probably make enough money in a month to retire on in 
London. 
> 
> I'm gonna be rich 
> 
> Rob 
 
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