ObscureDragom on November 17, 2009, 06:54:55 pm
First lets explain the broad wackyness of life by pointing out the "Poles" of life.

Most Freshwater animals cannot survive in Saltwater and most Saltwater animals cannot survive in Freshwater.

Most Anaerobic life cannot exist in contact with oxygen and most Aerobic life cannot exist without oxygen.

All form of life on earth use left-handed amino acid strings and finds right-handed amino strings toxic, We assume the same is true for life based on right-handed amino strings.

Now the human body is a Freshwater, Anaerobic, left-handed amino string environment.

With every descriptor in that line the number of alien virus's, fungi and bacteria that can even try to make a human a host drops by 50%.  So we have 12.5% of all alien infectious agents left in the competition.

Now the human body is also 37.0 C, under 1 G of pressure and already teams with dozens of different forms of life.

Those descriptors are the real kickers as they reduce the number by more then 50%.  Lets just make a broad guess like 85%.   Brings us down to 0.04% of infectious agents, or 1/2,500

Now this is the number chance the infection can get in the front door.

Now it has to be able to survive any range of formidable immune responses from a fever of 41.1 C to white blood cell  absorption to rejection of tissue (mostly skin).

Assuming 50% chance of success of these measures we come to 0.005% or 1/20,000

Just not betting odds.  And I'm being kinda generous.

JasonAW3 on November 18, 2009, 02:53:15 pm
So.  What does everyone say?  Burn the heretic?  Or make him wear a funny hat?

What if he already wears a funny hat?

I don't like hats, but if that's the rule on this site...


Hey, I'm all for funny hats, but will it fit inside his helmet as we make him dance a jaunty Irish Jig on the surface of Mars?





terry_freeman on November 19, 2009, 03:55:20 am
It is an error to assume that the probability distribution of both parts of a two-valued choice is 50-50. What if there are factors which skew life toward aerobic and left-handed proteins, etc?

ObscureDragom on November 23, 2009, 11:12:20 pm
It is an error to assume that the probability distribution of both parts of a two-valued choice is 50-50. What if there are factors which skew life toward aerobic and left-handed proteins, etc?

First there is the useful paradox of the environment of the human body is curiously anaerobic, despite the fact humans themselves are aerobic.

Second there is the possibility of using a different element other then Oxygen, like those funky subterranean bacterial mats that get by converting Sulfur into Sulfuric Acid to power their biology.

Yes there could be such factors, and of course those factors could actually skew in the opposite direction at the same time.

By which I mean that while 90% of all life in the universe could use left-handed amino acids, it is equally likely that 90% of all life in the universe uses right-handed amino acids.

Ah, xenobiology, the one true science.
« Last Edit: November 23, 2009, 11:20:37 pm by ObscureDragom »

wdg3rd on November 28, 2009, 10:25:44 pm

First there is the useful paradox of the environment of the human body is curiously anaerobic, despite the fact humans themselves are aerobic.

Pretty much every life-form that survived the introduction of oxygen to Earth's atmosphere is aerobic.  It's how they survived,  The only place you can find anaerobic life-forms is around volcanic vents or in canned food (and in government labs, but that's another story)

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By which I mean that while 90% of all life in the universe could use left-handed amino acids, it is equally likely that 90% of all life in the universe uses right-handed amino acids.

Actually, there is plenty of evidence that ultraviolet light (and a few other bands) tend to skew the twist of amino acids and the proteins made from them.  Other-handed life may be rare.

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Ah, xenobiology, the one true science.

It's not a science unless there is mathematics to back it up.  Get a census of Jovian frogs and hydrogen-based squids (whether sentient or not) and we''ll work on turning xenobiology into a science.
Ward Griffiths        wdg3rd@aol.com

Men will never be free until the last king is strangled with the entrails of the last priest.  --  Denis Diderot

 

anything