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Hands and brains

ReplyTo: Kelly

>> Of the total budget spend by companies. You said only 5% was used for R&D, I
>> say about 80% is used by getting the raw materials. Here on Earth those raw
>> materials are difficult to obtain, in space it may be much easier (just
>> scoop the surface) and thus less manpower is needed.
>Most industries don't spend 80% on raw material (probably more like 10% -
>30%) the bulk is in labor costs.  So automation will have a big effect.

OK, I'm wrong. But I don't understand how you can say that automation will
decrease the cost dramatically, since you are saying that automats need a
lot of maintenance and take a lot of efford to build.

>> Like a hairdresser, shoemaker, tailor, dentist, doctor, cook? Are these the
>> jobs you mean?
>> I wonder if we can come up with more than 100 or 1000 completely different
>> jobs that are needed in a starship.
>Well it takes 10,000 to operate an aircraft carrer, and far more than that to
>maintain it.  Add in other professions to maintain the entire civilization
>needed to support them, and you get millions.

Are there 10,000 people on one single "boat"?
There are only 100-200 people needed to operate a submarine and they are
able to live more than 1 year isolated from the outside world.

>> On the bottom of the sea, I can imagine, but in a high radiative field is
>> hard to believe, the DNA would be mutated beyond repair within seconds. Can
>> you recall the source? 
>Several sources.  Its an old story of some interest.  Last I remember for
>sure was Science.  They were studing the cell repair mecanisms that allow the
>bacteria they were studying to repair their genetic and tissua damage that
>fast.  (No not in secounds!)  They were fairly sure it developed to allow the
>bacteria to repair themselves fast enough to survive high temperatures, and
>woundered if it could be transfered to humans.  I think they said the cell
>repair rates were high enough to allow the bacteria to survive thousands of
>times the human fatal radiation dosage.  (Effectivly the radiation couldn't
>kill them untill it physically cooked them!)

100 Times, I can believe, even cockroaches can survive that (Of course they
have a better armour than bacteria). Now I only wonder how radiation levels
can be that low in reactors. I guess these bacteria had found a well
shielded place behind some bolds.

>The latest NASA reports say differently.  The Magelin probe showed the
>thinner crust during its radar scans.

It may be thin, I wasn't arguing that (It's no wonder if the surface
temperature is 450 degree Celcius, the cooling down of the core is much slower).
All I said was that most of the higher temperature was due to the greenhous

>> There are is a lot of dust and posionous gasses, which create a very dense
>> atmosphere (90 bar). This dense atmosphere full of greenhouse gasses (much
>> worse than CO2) and the higher radiation level are the main reasons for the
>> higher surface temperature.
>Given the debacle about greenhouse effect predictions on earth I'm cynical
>about predictions on alien worlds.

Forget the predictions, it is proven than several gasses like CO2 and SO2
have very well insulating properties. So the fact that these gasses are
present in abundance on Venus means that a greenhouse-effect is responsable
for the high temperature.

>Also its generally agreed that if earth
>was where Venus is, it would not become dramatically hotter.  (Well not as
>dramatic as Venus.  You could still live here.  But you'll want to move north
>a bit. ;)  )

Yes, but that is because Earth has a biosphere. If Earth had to do without
that and it would be moved to the place of Venus, then is would heat up and
once the greenhouse-effect took over there wouldn't be a way back.

>Unless you sell or to the developed world like the third world does.  Expect
>them to scream as their economies fold.

Maybe it's time for them to get their own economies...

>> My misunderstanding, but can food be kept for 20 years?
>Sure.  We kept some cold war rations around for that long without
>refrigeration.  With high tech, you can keep normal foods almost indefinatly.
> (Give or take a few problematic fruits like apples.)

OK, indefinatly, so a humble 60 years would be possible for a single way
mission :)

>> Why have these organisms never evolved beyond a single cell?
>> And if they did as you suggest, why did they change to use oxigen?
>Algae poluted the atmosphere with so much oxegen everything was killed off.
> To survive the remaining life forms had to adapt to oxegen or avoid oxegen
>rich areas (its hard to evolve multi celular when you in those little
>enclaves.).  Even now our cell nucleus is destroyed by oxegen contamination.
> But we do the best we can. ;)

Oh, I thought you were referring to those bacteria living near sea-vulcanos.
An organism (like algae) that gets all its energy from direct sunlight is
not likely to evolve to a multicellular moving organism, because it takes to
much energy to move.
So besides the reason that organisms had to use oxygen because otherwise
there was no place to stay.

>In a world without photosyntisis the non-oxegen forms could still dominate.

How? If they used chemicals for their energy, then the supply of those
chemicals better be almost infinite. Most of the chemicals that organisms
use these days are recycled by using photosyntesis. Only a small fraction of
chemicals is freed by vulcanos, hardly enough to sustain a group of lifeforms.

>We were preditors before we had brains.  Our ability to track game, and run
>for extreamly long distences without tiring, are our bigest adaptation for
>hunting.  Thou naturally we wouldn't be nearly as good at it without our

No, we were apes before we had big brains, and apes are no preditors.
(I never said that intelligent live could not come from wolves, but if it
would they need to change their claws first)

>> ---- Imagine you have a hand with a thumb and a
>> single finger, that would mean a serious handycap all things you could
>> normally do, would not be able or very hard, even many years after you had
>> become customed to it. (And we don't have a solid finger like crabs do)
>But what if you had 6 claw/hands like crabs doi?  In general our hands are
>very good for what we use them for, but their are many alternatives with
>stregths and weakness over ours.  Ours is not the only design that would
>work, or even the best of all possible hands (we've tested robots with

Crabs have 8 legs and 2 claws (or scissors) the legs are made for walking
(and that's just what they do ;) ).

A larger brain needs a larger body, larger bodies need larger legs. Having
more than 4 legs will mean a disadvantage because of the extra weight.
Even if they had more legs they probably couldn't miss more than 2 of them
to permanently free them for hands.

Also it would be unlikely that animals that stand on 4 legs would have only
a stump to stand on. Having a few small extremeties at each leg gives much
more stability.

So while there are creatures with more than 4 legs, they aren't likely to
support a big brain.
That leaves only 2 legs to support the hands. If these 2 hands want to do
anything constructive, they better have more than 2 fingers.

I also wonder if creatures with gills (using oxigen in the water) could have
a large brain. In the water you would need very large gills to get enough
oxigen for that brain. Only very large underwater animals could have a big
brain, but what would the advantage be for them? They already are at the top
of the food-chain.

>> So while an organism gets some usefull "hands" it also gets a smarter brain
>> to use that "hand". Once the brain gets bigger it may be usefull for other
>> purposes too, like better perception, better remembering, better learning.
>Most of our enlarged brain isn't devoted to our hands.  Dolphins brains are
>even larger (proportionally) than ours.  (Thou they are not evolved for
>inteligence.)  We are not the only model the universe could use.

Indeed, most of our brain isn't devoted to anything as far as we know. I
meant that a large part is devoted to what you can do with your hands.
Suppose you have a large brain, but no hands/legs to make use of it. There
would not be any advantage then to have a bigger brain, so it would not evolve.

(By the way I couldn't find the meaning of "chavanist", are you sure you
spelled it right? (I've an idea of the meaning though))

About Dolphins, they are a species that went back to the sea after living on
land, they are also air-breathing. So that may explain some of the size of
the brain.
You said proportionally, but for intelligence only the absolute size is
impotant. Besides that, dolphins are almost the same size we are. So if they
have big brains, they have to use them somehow otherwise it would be a bad
evolutionary design which is unlikely. I really wonder what a "fish" could
do when it was intelligent. It only could use its beak to construct something.

Since Dolphins don't seem more intelligent than the average dog, I've some
doubts about the real size of their brain, but I haven't any numbers at my
diposal to check it. (The latter really is a problem to me, the ideas are
clear but the numbers to back it up are often hard to find.)