Europa Dope (Re: why 'Martians' should be bipeds...)

[Phil Bigelow <bigelowp@juno.com>]

Solar System critters may all have the same basic plan, no matter on
which planet/moon they evolved.  Cross-planetary innoculation via
meteorites would be rare, but all it takes is one successful "jab" with
that meteoritic hypo and then all bets are off.

There are 3-4 Martian meteorites that have been observed to fall in
recent decades.  Assuming that one Martian meteorite falls per decade,
that equals roughly 100,000 Martian falls per million years.  Over a few
billion years, that means that a lot of  tonnage from the red planet has
landed on Earth.

If one or two spore-rich Earth meteorites made it all the way to Europa a
couple billion years ago, then we may have some rather interesting
expatriated Earth/Martian biology awaiting the arrival of our hot eager
ice probe.

The Long Duration Exposure Facility (LDEF), a NASA research satillite
launched by the shuttle in the 1980s, showed that certain bacterial
spores can remain viable in space for at *least* 6 years, provided that
the spores are shielded from ultraviolet radiation.  The spores remained
relatively uneffected by other types of danger (e.g., hard vacuum, heat,
cold, X-rays, gamma rays, and cosmic rays didn't harm the spores on the
Facility).

Yes, I do have a question for the list:  What is the current opinion on
the monophyly of all Earth life?

<pb> (the first Europa Dope)
--



On Fri, 01 Jul 2005 21:14:16 +0200 David Marjanovic
<david.marjanovic@gmx.at> writes:
> > In human ancestors, standing upright freed our hands to do other 
> things, 
> > specifically to carry things, like bananas and prey. Before long 
> we were 
> > fashioning stone into tools and weapons; vines and sinew into 
> string and 
> > rope; skins and leaves into garments and adornments. This led to 
> trade, 
> > greed, invention, the moon landing and MTV. So quadrupedal aliens 
> in 
> > hi-tech ware doesn't cut it for me.
> 
> You're merely arguing that _some_ sort of grasping organ is needed. 
> I just 
> say "elephant trunk". Or "spider monkey tail". And those are just 
> the 
> mammals. Nothing requires that such a grasping organ have evolved 
> from a 
> walking organ, and I don't think the number is too constrained 
> either.
> 
> > They were unprotected and apparently naive about life's littlest 
> denizens. 
> > Even in the late 60s we were cautious enough to quarantine our 
> astronauts 
> > [...]
> 
> Which was of course rather silly. It's not like any virus could just 
> infect 
> any cell. It needs to have the right surface proteins so the virus 
> can 
> attach in the first place, and that's just the start. Now remember 
> that our 
> 20 (OK, 22) amino acids are a _highly_ arbitrary selection of all 
> amino 
> acids that _could_ in principle occur in functional proteins... 
> besides, who 
> needs amino acids, perhaps glycolipids or whatever can do the tricks 
> just as 
> well... While we are at it, viruses need to replicate inside cells. 
> This 
> requires DNA and RNA. There doesn't appear to be a special reason 
> why we 
> have just these four bases and not any others. Pyridine bases could 
> bind 
> metal ions and conduct all sorts of interesting enzyme activities 
> without 
> proteins...
> 
> > PS. Do you think they'll ever do an invasion movie where the 
> aliens want 
> > our gold, want to force us to their religion and we give them 
> syphyllis?
> 
> Syphilis? How many _mammal_ species can get syphilis?
> 
> -------------------------------------
> "First let me say that I'm a big fan of carbon-based life. Some of 
> my best 
> friends are carbon-based."
> -- David Harry Grinspoon 
> 
> 
>