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Re: Hands and brains
Re: David@interworld.com (David Levine)
> > >
> > > About Dolphins, they are a species that went back to the sea after
> > > land, they are also air-breathing. So that may explain some of the size
> > > 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
> > > have big brains, they have to use them somehow otherwise it would be a
> > > evolutionary design which is unlikely. I really wonder what a "fish"
> I would disagree that only absolute size is important. I'm
> not positive, but I'm assuming elephant brains are quite
> larger than human brains. While social and intelligent
> animals, they're certainly not more intelligent than human
> beings. Perhaps the absolute size of a certain section
> of the brain? Like the cerebellum? I don't know enough
> about elephant anatomy to say whether or not one part of
> an elephant brain is larger than another part. Actually,
> my instinct tells me that there is some sort of minimum
> constant k=c*s, where s is size and c is connectivity (i.e.
> number of neural connections per brain cell)... so that
> creatures with smaller brains could still be intelligent if
> they had a higher density of connections. Well,
> actually, another possibility is that there is simply a minimum
> number of connections...
Yeah, Its assumed that you need a minimum size to have enough cells, for
enough interconnections, to get a complex enough brain; But you also need a
big enough brain to body ration so the brain has enough excess power to spare
Dolphin Brains are bigger in size and ratio than human brains. But human
brains use a larger fraction (10%) on intelegence. Dolphins sonar cortex is
as large as the human visual cortex (30% of human brain), so even though the
intelegence centers are far smaller, the total brain is larger.
> Re: email@example.com (Ric & Denisse Hedman)
> >>Well it takes 10,000 to operate an aircraft carrer, and far more than
> >>maintain it. Add in other professions to maintain the entire
> >>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.
> The average Aircraft Carrier today has a crew of around 5000. I'm not sure
> of the number but about 1/2 are there to take care of the planes and fly
> them. 1/2 of the other 1/2 are there to maintain the systems to launch and
> retrieve the planes. The rest run the ship. During Viet Nam some carrier
> up to 8000 crew.
Opps. I knew Carrier crews were half for the ship, and half for the flight
wing. But I couldn't remember if it was 5000 total, or by section. After I
sent the E-mail I started to wounder about 10,000
> Re: firstname.lastname@example.org (Kevin C Houston)
> On Sun, 28 Jan 1996, Timothy van der Linden wrote:
> > ReplyTo: Kelly
> > >Well it takes 10,000 to operate an aircraft carrer, and far more than
> > >maintain it. Add in other professions to maintain the entire
> > >needed to support them, and you get millions.
> How many of those are actually maintaining the boat, and how many are
> training to use the weapons that boat is carrying. ----
No, they generally train crews before they send them out. Fewer ships sink
that way. ;)
> -----you keep bringing up
> the military model Kelly, Are you assuming we are going to have to fight
> someone/thing. I'll say again, the military is a bad example, many of
> the people are engaged in specialized activity which has nothing to do
> with the maintainance of the boat. Another large part of the crew is
> engaged in activity to repair any damage that the enemy will inflict on
> them. both groups would not be needed in a star-ship (given the fact
> that we have written off weapon systems as unescessary, our only defense
> upon meeting a hostile ship would be to surrender or self-destruct)
I still think the military systems are the best example we have. Certianly
the starship will be acting like an aircraft carrier. (Yes a large fraction
of the starships crew will be engaged in specialize jobs not related to
maintaining the ship. Otherwise why send them?) Also only the military
operates large numbers of specialized people, in extreamly isolated,
hostile/toxic areas, and gets them out again alive. Also they have done a
goodly fraction of the exploration of this planet.
I'm not saying we need the ship organized along military ranks, but our
equipment will probably be much more like military gear, than anything else.
Heavy, tough, built to operate in extreamly bad areas with little civilized
infastructure to support them. Some of the equipment may very well be
derived from military equipment. (Who else will have decades of bio-warfare
experence in their systems designs?)
Oh, the starship woun't be armed (though with the power of its engines and
interstellar laser com, that might be a debatable point!), the landers and
rovers would be armed and armored. I was talking about making sure the
equipment could handel an attack by a pack of Tyronasaurus Rex's, and no one
seemed to object.
> > > >> 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
> > > (Give or take a few problematic fruits like apples.)
> > OK, indefinatly, so a humble 60 years would be possible for a single way
> > mission :)
> Even if we can keep such foods, my carrots example shows that it's
> cheaper in both mass and space to grow many foods rather than carry them .
I did a detailed breakdown of groceries per 20 years vs a selfsustaining farm
and found the break even point was 20-30 years (depending). I CAN'T FIND
IT!! Its probably in the LIT Newsletters, so if Dave finishes the search
engine I can find it that way. Or I might figure out where I put it on my
hard drive. Anyway I'll forward that when I can find it.
> >> >In a world without photosyntisis the non-oxegen forms could still
> you could have photosynthesis, without having oxygen. in our system,
> plants break down water into hydrogen and oxygen, the hydrogen is tacked
> onto a CO2 subunit, and then built up into carbo-hydrates. It is no
> large stretch of the imagination to envision a system where the [Plants]
> break down H2S and release S2 into the atmosphere tacking the hydrogen
> onto a CO2 etc etc
Interesting. I hadn't thought of that. I had though of fully chemosynthesis
based ecologies like we have here in the deep ocean. But never a different
type of photosynthesis.
> > (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))
Sorry, I keep forgeting you don't always now informal english.
> > About Dolphins, they are a species that went back to the sea after living
> > land, they are also air-breathing. ----
> > ----- even the lowly prairie dog has a
> rudimentary language. It is sophisticated enough to convey the following
> In short, the prairie dogs gave different vocalizations when a dog, or a
> human approached the nest, and gave different vocalizations when the same
> man wearing different colored jacket walked through. they also gave some
> indication what the direction of approach was. When a man walked in from
> the North, the voalizations were recorded, and played back several days
> later. every member of the prairie dog nest looked, not at the speakers,
> but to the north. and when Hawk warnings are recorded and played back,
> they all look to the sky
Woah?! Neat. I knew a lot of animals and insects had language (certainly my
dog demonstrates that effectivly) but I never heard of the prarie dog tests.
> RE: T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden)
> ReplyTo: Kelly
> >> Of the total budget spend by companies. You said only 5% was used for
> >> say about 80% is used by getting the raw materials. Here on Earth those
> >> 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.
So do people.
Automation allows a few skilled people to do the work of a larger number of
people without automation. It does not allow the automation system to work
by itself without people. As long as their are people to fix and operate it,
automate systems will work well and productivly. Which is why all large
manufacturing industries use them.
> >> Like a hairdresser, shoemaker, tailor, dentist, doctor, cook? Are these
> >> jobs you mean?
> >> I wonder if we can come up with more than 100 or 1000 completely
> >> jobs that are needed in a starship.
> >Well it takes 10,000 to operate an aircraft carrer, and far more than that
> >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.
Submarines are much simpler than carriers, and they seldom operate more than
3 months without coming into port. Actually I can't think of one ever going
a year submurged? (RICK!! ??)
> >> On the bottom of the sea, I can imagine, but in a high radiative field
> >> hard to believe, the DNA would be mutated beyond repair within seconds.
> >> 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
> >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
> >bacteria to repair themselves fast enough to survive high temperatures,
> >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
> >times the human fatal radiation dosage. (Effectivly the radiation
> >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.
No, the bacteria remained directly exposed to the radiation. The only
shielding would be the cooling water batween them and the reactor core.
> >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
> All I said was that most of the higher temperature was due to the greenhous
Sorry, no the greenhouse effect is considered a dabatable effect at all, even
> >> There are is a lot of dust and posionous gasses, which create a very
> >> atmosphere (90 bar). This dense atmosphere full of greenhouse gasses
> >> worse than CO2) and the higher radiation level are the main reasons for
> >> 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.
No it doesn't, it just meen their are insulating gases in the air. It
doesn't even tell you if they are keeping heat in, or out.
> >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
> >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.
No, earth biosphere trims its temperature a bit, but not by hundreds of
degrees! If that were true Earth would have been unable to ever evolve life.
> >Unless you sell or to the developed world like the third world does.
> >them to scream as their economies fold.
> Maybe it's time for them to get their own economies...
True, but screeming and blaming others is so much easier.
> >> 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
> > (Give or take a few problematic fruits like apples.)
> OK, indefinatly, so a humble 60 years would be possible for a single way
> mission :)
Well, you wouldn't starve anyway.
> >> 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
> > To survive the remaining life forms had to adapt to oxegen or avoid
> >rich areas (its hard to evolve multi celular when you in those little
> >enclaves.). Even now our cell nucleus is destroyed by oxegen
> > But we do the best we can. ;)
> Oh, I thought you were referring to those bacteria living near
Some are there, or in stagnent pools (like parts of SanFransico bay) that
have little or no oxegen. But no large ecologies can develop in such
> >In a world without photosyntisis the non-oxegen forms could still
> 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
> chemicals is freed by vulcanos, hardly enough to sustain a group of
Depends on the planets and its chemistry.
> >We were preditors before we had brains. Our ability to track game, and
> >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 not preditors.
We evolved from chimps, which are predators. (Unlike Gorillas.) Those
chimps evolved (after some odd twists) into plains preditors and scavengers.
We developed that (and primative tool making), before our brains expanded
> (I never said that intelligent live could not come from wolves, but if it
> would they need to change their claws first)
They could develop intelegence. A need for that just mean you have complex
problem between you and a steed meal. Wolve greatest problem toward
developing intelegence is that they are to good at what they do. Racoons or
Otters would be a better bet. They depend more on cleverness, and use hands
and some (unfashioned) tools.
> >> ---- 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
> >> 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 ;) ).
They have about 6 - 8 claws, but the inner ones are very small and
specialized for tearing down food for the mouth.
> 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.
???!! You have some strange and unsupported assumptions there. MOst of
earths walking life forms have more than 4 legs. Almost all of the rest have
4. Given that humans are fairly small as animals go, I can't see any
justification in assuming large 4 or six limbed creatures are impossible.
Hell we have predatores in north america that are almost a ton!
> I also wonder if creatures with gills (using oxigen in the water) could
> 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
> of the food-chain.
Gills in water actually need les body mass than lungs in air.
> >> So while an organism gets some usefull "hands" it also gets a smarter
> >> to use that "hand". Once the brain gets bigger it may be usefull for
> >> purposes too, like better perception, better remembering, better
> >Most of our enlarged brain isn't devoted to our hands. Dolphins brains
> >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. --
Actually we do know what all the centers of the brain do, just not how they
> --- 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
The biggest section of the human brain evolved to use the eyes, not hands.
Niether are used in itelegence, that evolved separatly.