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Offline jellyjan

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Communicating With Aliens
« on: 27/01/2008 10:54:24 »
I know the subject may seem slightly immature but there are two questions behind this topic.

1) How could we possibly scientifically communicate with aliens? 

2) What else besides light can travel through space(vacuum)?


 

Offline syhprum

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« Reply #1 on: 27/01/2008 12:05:27 »
I do not think we can communicate with aliens to any great degree unless they have similar senses to us and live in a similar environment.
We have 'alien' creatures living amongst us with well developed senses such as Chimpanzees and dolphins but we can only have very limited communication with them.

All things can move thru space!, electromagnetic radiation at the speed of light and objects with mass at any speed up to that limit
 

Offline Soul Surfer

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« Reply #2 on: 27/01/2008 18:58:45 »
Basic mathematics is something common to all lifeforms with advanced technology so the generally accepted route to communication is via mathematics.  this allows the generation of basig symbols which are developed and elaborated to enable communication.  This would apply to any lifeform however it was constructed.  A good example of this process is described in the book and film "contact" by Carl Sagan.
 

Offline opus

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« Reply #3 on: 27/01/2008 20:07:40 »
Greetings Earth people- 4467832256?
 

Offline DoctorBeaver

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« Reply #4 on: 27/01/2008 22:44:46 »
Basic mathematics is something common to all lifeforms with advanced technology so the generally accepted route to communication is via mathematics.  this allows the generation of basig symbols which are developed and elaborated to enable communication.  This would apply to any lifeform however it was constructed.  A good example of this process is described in the book and film "contact" by Carl Sagan.

But if they had neither sight nor hearing, how could we communicate the mathematics to them, or vice versa? It's not easy to tap Morse code on someone's arm if they are 10 squillion miles away.
 

Offline turnipsock

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« Reply #5 on: 27/01/2008 22:58:05 »
Doesn't Voyager 1 have a naked scientist type logo on the side and there is some mathimatical progression involved somewhere. This was done incase some aliens came across it.

Voyager 1 is a real hero. It's still going and is expected to keep sending back data until at least 2020...that's 43 years after it launch! I'll be happy if my 76 merc lasts that long.

is that your phone number Opus? if it is, I'm phoning you tomorrow.
« Last Edit: 27/01/2008 23:01:44 by turnipsock »
 

Offline DoctorBeaver

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« Reply #6 on: 27/01/2008 23:33:40 »
Doesn't Voyager 1 have a naked scientist type logo on the side and there is some mathimatical progression involved somewhere. This was done incase some aliens came across it.

Voyager 1 is a real hero. It's still going and is expected to keep sending back data until at least 2020...that's 43 years after it launch! I'll be happy if my 76 merc lasts that long.

There are all sorts of things on Voyager, but you are correct. It does have that Leonardo DaVinci Naked Scientists thingy on it. However, if our aliens have neither sight nor hearing, they wouldn't be able to perceive any of the stuff we sent.
 

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« Reply #7 on: 28/01/2008 00:57:01 »
We cannot even be sure how large the aliens would be.  Is the voyager going to look like a speck of sand, or like something the size of a mountain, in which case, at what scale will they view what they see (maybe they will pay more attention to the surface texture of the metal than to the symbols writ large on the side).

As has been mentioned - mathematics is a logical connection between things, but although we do have a domestic set of symbols we conventionally use to describe mathematics, these symbols are by no means universal, but merely inventions of our own.  The underlying relationships may be universal, but if they don't understand the symbols, then the relationships we may believe they describe are meaningless to them.

In any case, one of the problems with mathematics is that it is too universal (in the nature of the relationships - not in the symbolism).  Meaning is derived from understanding large similarities combined with small differences.  If all things are totally similar, there is no meaning.  This is the difference between DNA, which has lots of irregularities, and so lots of information; and a simple polymer, that has no irregularities, and so no meaningful information.
 

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« Reply #8 on: 28/01/2008 01:38:15 »
I think the problem with communicating with aliens (without two way interactive communication) is a little like the questions of whether there is a God.  We need to send them something that demonstrates that there is intelligence out there in the universe (i.e. us).  The problem is not unlike our looking out to the universe around us, and arguing whether the complexity/simplicity of that universe is proof of a Godlike intelligence, or is just proof of our own intelligent understanding of natural phenomena.  So too, if an alien life were to see the voyager craft floating in space towards them (or even crashing down upon their heads - for it may indeed be a space hazard for them), they could argue endlessly as to whether the complex patters on the craft really represent alien intelligence (i.e. us), or whether it is just a natural phenomena they have to find an explanation for.

Ofcourse, the dichotomy between intelligence and natural is not that simple, and much of what is regarded as intelligent or unintelligent is probably down to prejudice.  Honey bees can manufacture sophisticated, and mathematically elegant, hives - yet we do not accord them a high intelligence.
« Last Edit: 28/01/2008 01:42:17 by another_someone »
 

Offline Pumblechook

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« Reply #9 on: 28/01/2008 13:32:58 »
There has been threads on radio communication over vast distances and the calculations show that transmitters thousands of times more powerful than we have now would be required.

Even the SETI groups admit that aliens would not be able to hear our flea power transmissions and they are relying on aliens having much more powerful ones.
 

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« Reply #10 on: 28/01/2008 14:48:51 »
There has been threads on radio communication over vast distances and the calculations show that transmitters thousands of times more powerful than we have now would be required.

Are you sure about this?

I have absolutely no doubt that this is true of narrow spectrum transmissions, but I am thinking of very wide spectrum transmission with massive data redundancy allowing effective reconstruction even when the signal to noise ratio is minute (after all, the problem with distance is not that the signal will not reach the distance, only that the signal to noise ratio would be so extreme that you would need a very complex level of signal processing to obtain any useful information with those signal to noise ratios).

Ofcourse, as for SETI - the point is, unless they know how to decode the encoding mechanism, it may well not be possible for them to understand the signal even though they would be receiving it.
 

lyner

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« Reply #11 on: 28/01/2008 16:56:30 »
Quote
We cannot even be sure how large the aliens would be.  Is the voyager going to look like a speck of sand, or like something the size of a mountain, in which case, at what scale will they view what they see (maybe they will pay more attention to the surface texture of the metal than to the symbols writ large on the side).
Actually, if we assume basic life processes as being similar to ours then we can. We do have some idea about upper and lower size limits. Any creatures of fly size would be, necessarily, limited in brain power (numbers of cells / memory elements)  and, for engineering reasons, they would need to build ships around the size of human's space ships  in order to leave a planet of  Earth-like  size.
Also, there are upper limits to size, based on strength of materials  available for skeletons etc.
Evolutionary processes would probably produce successful species on a not-too-dissimilar size to us on any planet which could support similar biochemistry.
That is unless they are based on some bizarre chemical basis which we haven't  though of yet. Which is not impossible, of course.
I could imagine a range of body masses spanning a ratio of, perhaps, ten to one? Certainly not more than 100:1.
 

Offline syhprum

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« Reply #12 on: 28/01/2008 17:10:40 »
If we took a ludicrously optimistic case of an Earth sized planet orbiting a Sun type star in the 'Goldilocks' zone say ten light years away and received coherent signals from it of such strength that a one bit per second communication channel could be set up.
Assuming they were transmitting something like a 'CQ' what could we do about it, we can no longer afford to buy time on large telescopes now that we waste our money on wars!
How many twenty year contacts could be run before any meaningful information could be exchanged, all we could glean is that at least there are 'Aliens' out there that can build radio equipment
 

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« Reply #13 on: 28/01/2008 18:14:45 »
Actually, if we assume basic life processes as being similar to ours then we can.

I don't like assumptions - but then, I suppose the real problem, and one that has never been properly answered, is what do we define as life?  It may be that you could argue that we define life as being composed of processes like ours, and if it was not of processes such as ours, we would disqualify it from being called living.

We do have some idea about upper and lower size limits. Any creatures of fly size would be, necessarily, limited in brain power (numbers of cells / memory elements)  and, for engineering reasons, they would need to build ships around the size of human's space ships  in order to leave a planet of  Earth-like  size.

I don't actually believe the human animal is that bright at all - it is human society that is intelligent.

So the question should not be about whether a fly could be as intelligent as a human, but whether a society of flies (or similar sized life form) could be as intelligent as humans.

Bear in mind that the human being is not themselves a monolithic entity, but just a collection of cooperating cells.  Not flies, but bees, are also strongly cooperative, and so can achieve far more than any single bee or fly could attain on their own (although their is no doubt that the number of cells in a human society exceeds the number of cells in a single bee society).

If a living entity could find novel ways of cooperating at a cellular level, then maybe what we consider an animal might not even exist, yet the collective intelligence of all those cells could still be leveraged.

We presently assume that life can only exist on Earthlike planets (we have changed out mind on this several times).  Certainly, it is reasonable to assume that Earthlike life could only exist on an Earthlike planet - but then, we are back to what we consider to be life?

I am not sure whether I accept your limitation on the size of a spacecraft.  It rather depends on what criteria you are using.

Certainly, if one is talking about present rocket technologies (and there has been much debate in other threads about whether rockets are really an ideal technology for space launches), the smaller the rocket, the less fuel needs to be carried, and so you have a feedback of being able to even further scale back the size of the overall rocket.

There might be issues about the degree of protection that a small spacecraft may offer its occupants - but that also depends on how much protection they need.

Even within our own experience, we do produce much smaller launch vehicles for unmanned launches (although the smallest are not likely to reach orbital altitudes).  Ofcourse, we have ourselves been limited to existing human scale technologies to achieve that.  I would ask that if we were able to use nano-scale technologies, is it really the case that we could not create very much smaller launch vehicles for nano-scale or micro scale payloads?

Also, there are upper limits to size, based on strength of materials  available for skeletons etc.

Yes, but that is because skeletons were evolved to handle Earth's gravity, and to produce life forms of a given scale within that gravity.

Trees, that do not rely on bone, are capable of growing much higher.  Even life that does rely on bones, in particular, marine life, is also not so constrained on size.

I would think it as likely that the real limitation on size probably has less to do with structures (other structures can be used) as the availability of energy, which if radically different from that available on Earth, would imply a much hotter environment, which would preclude the development of Earthlike life.

I could imagine a range of body masses spanning a ratio of, perhaps, ten to one? Certainly not more than 100:1.

Not sure what you mean by this?

Blue Whales are up to 170 tonnes, and heavy as I may be, I am still well under 1% of that body mass.

If you are saying that you cannot imagine something 100 times heavier than a Blue Whale, I am not even sure that is true, but the limiting factor, in my opinion, is not the size of a single animal, but rather the amount of total biomass an environment can sustain (which goes back to my question about energy, as well as the amount of space available), and what proportion of that biomass can reasonably be vested in one organism (bearing in mind that the organism must feed on something, and if it feeds on other organisms, then there must be a substantial proportion of the biomass of the planet vested in the food organisms - and the only way around this is if even the largest of organisms were lithotrophs, but then, is this evolutionarily viable?).
 

Offline opus

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« Reply #14 on: 28/01/2008 19:53:56 »
No earth-being turnipsock- I'm trying to communicate mathematically!
 

lyner

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« Reply #15 on: 29/01/2008 10:28:32 »
Quote
Trees, that do not rely on bone, are capable of growing much higher.  Even life that does rely on bones, in particular, marine life, is also not so constrained on size.
But they don't need to carry enough muscle to move them around!
Quote
Blue Whales are up to 170 tonnes, and heavy as I may be, I am still well under 1% of that body mass.
Woops - I forgot about  sea organisms. However, their technology could be a bit limited if, as with humans, they need fire to get started.
Quote
Not flies, but bees, are also strongly cooperative, and so can achieve far more than any single bee or fly could attain on their own (although their is no doubt that the number of cells in a human society exceeds the number of cells in a single bee society)
This is true, but there are many more possible interconnections between the cells of a complex brain than between the brains of 'simple' individuals. I think this is relevant where sophisticated ideas and tasks come into play.

There is something else to consider about aliens. The more different they are, from us, the less 'interested' we would be in what they had to say to us. It is probably true to say that, if they looked a lot like us, we would be much more empathic (or, possible suspicious). The conspiracy theorists would just love it if they looked like people dressed up.

Initial 'messages', would have to be extremely simple - prime numbers sent in binary form or musically related frequencies. etc. etc.
« Last Edit: 29/01/2008 10:31:26 by sophiecentaur »
 

Offline syhprum

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« Reply #16 on: 30/01/2008 19:33:24 »
Although on a much smaller scale than communicating with aliens dozens of light years away I have had a taste of it trying to make travel arrangements in Melbourne.
Although E.mails zip across in under a second the 11 hour difference in local time means that one never gets a reply in less than 24 hours.
 

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« Reply #17 on: 30/01/2008 20:27:36 »
Quote
Trees, that do not rely on bone, are capable of growing much higher.  Even life that does rely on bones, in particular, marine life, is also not so constrained on size.
But they don't need to carry enough muscle to move them around!

But human beings have been moving trees around with their own muscles since many millennia.

True, it would take a fair amount of muscle to get a tree to run for any distance at 30mph, but simply moving around at a very slow pace would not take that much muscle, and as I said, we humans have provided the muscle to do that for some time (long before we invented the steam engine).

As I said, I don't really believe the limiting factor is structural, but energy - it takes a lot of energy to move a tree, and one or two trees can be moved by the odd animal (elephants do it quite well), but to supply every tree with the power to move would require a good deal of energy (one elephant per tree in the world would be an infeasible undertaking).

Woops - I forgot about  sea organisms. However, their technology could be a bit limited if, as with humans, they need fire to get started.

Why did we need fire?

Certainly, the industrial revolution required fire; and even the bronze age revolution did require fire.

It is conceivable that a submarine life could have used submarine volcanoes or even mid oceanic vents as an alternate heat source.

There were two things that we have that whales lack.  Firstly, we have fingers (so any marine intelligent life would have to develop appendages that could have a similar dexterity to our fingers - octopuses are not that bad - maybe the closest, but still some way off).

Then, what really does distinguish us from whales.  The most important things is our weakness.  We had to use our brains simply because we lacked the brawn to do otherwise.  This is why an intelligent life form cannot be the largest life on the planet - if it had that much brute force on its side, it would never have the driving force to need to develop any substantial technology.

This is true, but there are many more possible interconnections between the cells of a complex brain than between the brains of 'simple' individuals. I think this is relevant where sophisticated ideas and tasks come into play.

It is not the number of connections that matter, it is the speed of information transfer that matters (not that, in the design that life uses on the planet, for that too, it is still true that bandwidth is better for shorter distances than for longer ones).

Moving away from carbon based cellular life, and looking at electronic components, it is still true that components that are connected with short pieces of wire can sustain higher transmission bandwidth than components that are separated by longer distances (e.g. by wireless networks); but nonetheless, there are advantages also to having components are are more widely dispersed that communicate over lower bandwidth transmissions.

Even with regard to carbon based cellular life, while it is true that cells that are in intimate proximity to each other have a much higher information bandwidth, the logical conclusion to this is that a single organisms that contains the same number of cells as 6 billion humans should have more intelligence than 6 billion humans that are separated from each other, and have to use relatively low bandwidth communication (e.g. speech) to communicate with each other.  Clearly, the evidence seems to be the contrary, that there is an optimum balance between have small blocks of cells with high speed communication between them, and those blocks then more widely dispersed, and using low speed communication between the individual blocks.  Exactly what defines where this optimum unit size lies is not something I would claim to properly understand, but I have no reason to believe that the size of a human being necessarily defines that optimum (it must to some extent depend on what the relative difference between the speed of communication between adjacent cells and more widely separated bodies, and anything that effects the relationship between the speed of those two levels of communication must impact upon the ideal unit size for an individual unit).

There is something else to consider about aliens. The more different they are, from us, the less 'interested' we would be in what they had to say to us. It is probably true to say that, if they looked a lot like us, we would be much more empathic (or, possible suspicious). The conspiracy theorists would just love it if they looked like people dressed up.


Indeed - this goes back to what I was saying above - if it is very unlike us, we would probably disqualify it as life, even though it may well function similarly to life in an abstract sense.

Initial 'messages', would have to be extremely simple - prime numbers sent in binary form or musically related frequencies. etc. etc.

So if you received a set of pulses that amounted to a primary number in binary form, how would you know it was from a living entity (or, more precisely, from an intelligent living entity).  Many things, such as the patterns of petals on a flower, use the Fabroccini numbers - does that prove flowers are intelligent?  Are prime numbers somehow more intelligent than Fabroccini numbers?
 

Offline Saganist

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« Reply #18 on: 31/01/2008 07:13:47 »
Hi guys,

I think communication with the far reaches of the multiverse are far more attainable than physically getting around the cosmos. I picture some sort of video conferencing with far removed neighbors.

I do some 3D chat at newbielink:http://www.cybertown.com/main_ieframes.html [nonactive]. This involves the use of avatars. Since trying this type of limited virtual reality, I feel that this type of communication would be a basis for interstellar interaction.

My best guess is that signals carrying information would be far easier to send to far reaches of the cosmos, than physical travel. Somehow I see this type of faster-than light-communications as involving the sending of signals via extra dimensions.

First contact would be most interesting. I am sure the first non-random signal we receive will be very strange in content indeed.

I imagine there will be quite a learning curve in both species reaching some common communication exchange. But if this happens, then some sort of exchange of virtual realtiy chat platform could be shared. Instead of going to Zula Prime in the Nth galaxy or them coming here, we meet in our computers and assume avatars.

We can recreate a virtual  earth environment for them to explore and they could create a Zula Prime virtual environment to check out. They can show us what they look like by their avatars and we do the same.

Cheers.

Saganist
 

lyner

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« Reply #19 on: 31/01/2008 11:57:20 »
Organisms evolve to fit their surroundings in competition with other organisms. OK you can move a tree with human muscles but that's not a big organism; it's a small organism doing some work on a big object. Humans can also run around, defend themselves and chase prey. A 10m human would be no use as a predator; it would have to photosynthesise and would need no brain. 'Intelligence' develops where it is necessary / advantageous; carnivores and omnivores do better when they are intelligent. 'Too much' intelligence is wasted on herbivores so they don't tend to be that smart -just be strong or run fast, which isn't a good starter for 'civilisation' or technology.
Where there has been evolution in isolation -  Australia / Galapagos Islands / the sea etc. we find that species develop in parallel fashion, with predators and prey all taking up equivalent roles. There are certain optimum arrangements for given circumstances and these are what develop favourably. There is no reason to suppose that carbon-based  life on  another planet with 'Goldilocks' conditions would end up developing in a wildly different fashion. I agree that you can dream up all sorts of life forms but Chemistry has to rule. You need complex molecules for 'life' and there is nothing quite so useful as Carbon for this under Earthlike conditions. Is there evidence of alternative complex molecules existing under wildly different conditions in the same way as we can detect the presence of Methane etc. all over the place?
Speculation is only worth while when it is based on a hint of reason or we'll have fairies at the bottom of the garden.
Wales and Fingers: We didn't do well BECAUSE we had fingers; our evolutionary path gave us rudimentary fingers and a crude ability to use them, all in the same process and we ended up with what we have now. Whales'  ancestors actually DISCARDED what could have been fingers when they took to the sea and needed flippers, not hands. It seems that organisms. once committed to a particular path, carry on in that direction, changing only when circumstances change radically.
Potential candidates for Alien civilisations need to have gone through similar processes to what we have been through and in similar timescales, too. Any 'top' organism has to reach a level before there is some extinction event which gives another organism the chance to get to the 'top'.
What do I mean by 'top'? I suppose I mean to be successful reproducers and to  want to and to be able to communicate with other similar organisms. There are loads of other prolific species which don't give a monkey's about the others except as potential danger of dinner.
I guess it is that majority  that we should be looking for, but we will have to go there to find them; they wouldn't have invented Radio.
On the subject of brain size, there is a definite upper limit on human brain size and that is imposed by the restrictions of the female birth canal and on the necessity of  having and supporting a skull to protect it whilst we are walking about.
« Last Edit: 31/01/2008 12:00:52 by sophiecentaur »
 

another_someone

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« Reply #20 on: 01/02/2008 02:48:56 »
Organisms evolve to fit their surroundings in competition with other organisms.

Agreed, but all that means is you cannot say how an organism will evolve until you know the environment.

OK you can move a tree with human muscles but that's not a big organism; it's a small organism doing some work on a big object.

That is not the point I was making - only that it is not beyond nature to create muscles capable of moving trees (ofcourse, why would a tree have such muscles itself is another matter).

Humans can also run around, defend themselves and chase prey. A 10m human would be no use as a predator; it would have to photosynthesise and would need no brain.

Trees don't run around, and humans may not have attained 10 metres in height, but various dinosaurs have various claims of size that exceed that (exact maximum sizes seem somewhat mired in controversy - the largest complete seems to be a Brachiosaurus at around 12m tall, but various partial finds of sauropods have been speculated to be up to 18m tall, and 40m long).

Nature can, in the right conditions, be extrely diverse.

'Intelligence' develops where it is necessary / advantageous; carnivores and omnivores do better when they are intelligent. 'Too much' intelligence is wasted on herbivores so they don't tend to be that smart -just be strong or run fast, which isn't a good starter for 'civilisation' or technology.

This is a common stereotype, but I'm not sure how valid it is - but again, it depends on what you consider to be intelligence.

Certainly, animals that have a wider range of food sources will tend to have more curiosity, because they will try new things to see if they are edible.  This has nothing to do with whether they specifically are hunters or not.

Snakes, which are obligate carnivores, are certainly not more intelligent than elephants, which are pure herbivores.  Whether a gorilla (which is a herbivore) is less intelligent than a chimpanzee (which is an omnivore), I am not sure about.  Chimpanzees do seem to have the greater curiosity, but then we come down to whether curiosity is a measure of intelligence?

One think I believe one may reasonably say about that which we recognise as intelligence, is that it is a social phenomenon: which is why elephants, who though herbivores, are highly social and highly intelligent; while snakes, which are obligate carnivores, lack any social structure, and lack much in terms of intelligence.

Another factor that is relevant would be life expectancy.  There is no point in spending 10 years teaching a juvenile the skills of life, if they only have an 11 year life span.

Where there has been evolution in isolation -  Australia / Galapagos Islands / the sea etc. we find that species develop in parallel fashion, with predators and prey all taking up equivalent roles. There are certain optimum arrangements for given circumstances and these are what develop favourably.

The islands may have been isolated insofar as animal migrations were concerned, but they were not environmentally isolated - they still had the same wider environment to cope with.  Also, even their isolation, insofar as it did exist, was only very transient in evolutionary terms (most of these places were not isolated at the time of the dinosaurs, so they still shared a lot of common history with the rest of the planet, even if the most recent part of that history was slightly divergent).

There is no reason to suppose that carbon-based  life on  another planet with 'Goldilocks' conditions would end up developing in a wildly different fashion. I agree that you can dream up all sorts of life forms but Chemistry has to rule. You need complex molecules for 'life' and there is nothing quite so useful as Carbon for this under Earthlike conditions. Is there evidence of alternative complex molecules existing under wildly different conditions in the same way as we can detect the presence of Methane etc. all over the place?

I am willing, in the absence of specific evidence for alternatives, to accept carbon as the basis of alien life (at least - and this is a key point, for initial alien life).

The main issue is that while the thing we associate most with life is carbon, in fact carbon alone would simply not be enough.  We have a complex mix of carbon, hydrogen, oxygen, phosphorous, ..., all the way down to trace amounts of iron and chromium.  All of these are critical for life as we live it, but if the ratio of the abundance of these lesser elements was different, then what difference would that make to the life as it existed?

For instance, as has been discussed on a number of other threads on this forum, the importance of vitamin D to all animal life (I don't believe it only applies to vertebrates, or even with the inclusion of animals with exoskeletons, although I may be wrong about this).  What vitamin D does is help manage the transport of calcium.  What would happen on a planet with more, or less, calcium than exists on our planet?

Bear in mind that the conditions on Earth are not mandated by our being 93 million miles from a medium sized star - they are as much to do with the conditions that formed our moon, which might have been very different elsewhere in the universe.

Even on this planet, just a few tens of millions of years ago, oxygen levels in the atmosphere were much higher than they are today (and earlier on, no oxygen was at all), so all of this makes an enormous difference to the amount of energy available for life, and so what kind of life can exist.

Speculation is only worth while when it is based on a hint of reason or we'll have fairies at the bottom of the garden.

The fact of the matter is we do not have any hint of reason that extraterrestrial life exists at all, so taking that logic, one could argue that all speculation, of whatever form, concerning extraterrestrial life is futile, otherwise we might have fairies at the end of the garden.

The questions we are asking are not "does extraterrestrial life exist?", much less are we asking "what form does extraterrestrial life take?", the question is "what are the limiting parameters that might dictate the possible forms that extraterrestrial life might take?".  We are indeed working largely with an absence of evidence, so does this, in your view, make the question futile?

Wales and Fingers: We didn't do well BECAUSE we had fingers; our evolutionary path gave us rudimentary fingers and a crude ability to use them, all in the same process and we ended up with what we have now.

Whales'  ancestors actually DISCARDED what could have been fingers when they took to the sea and needed flippers, not hands. It seems that organisms. once committed to a particular path, carry on in that direction, changing only when circumstances change radically.

Yes, but without those rudimentary fingers, we would not have learnt to manipulate objects, and with that ability to manipulate so we developed evolutionary pressures to become ever more dexterous in our manipulations.  Had we not manipulated in the first place, there would be no basis upon which the evolutionary pressure could have applied.

Yes, whales needed flippers more than they needed fingers, and this limited their ability to develop tools (although not so much their ability to develop language).

Potential candidates for Alien civilisations need to have gone through similar processes to what we have been through and in similar timescales, too.

You have yet to show any evidence for this statement.

Certainly, there does need to be a similarity in the processes, but similarity in a broad sense, and similar in a specific sense, are two different things.  I am not saying you are wrong, only that the statement seems to lack specific evidence, and so I would take it as merely speculative (given what you said earlier about drawing conclusions in the absence of evidence).

Any 'top' organism has to reach a level before there is some extinction event which gives another organism the chance to get to the 'top'.
What do I mean by 'top'? I suppose I mean to be successful reproducers and to  want to and to be able to communicate with other similar organisms. There are loads of other prolific species which don't give a monkey's about the others except as potential danger of dinner.

Very few for which this statement is absolute, although there is a wide degree of variation to the extent that it is true of different species.

It is said there are about as many rats in the country as there are humans, and probably even more mice.  Both of these animals can communicate and socialise well.  Both mice and rats tend to thrive in the presence of man, which is why their population sizes tend to be proportionate to the human population.


On the subject of brain size, there is a definite upper limit on human brain size and that is imposed by the restrictions of the female birth canal and on the necessity of  having and supporting a skull to protect it whilst we are walking about.

You are ofcourse talking about a placental bipedal animal.  For a quadruped, or marsupial, or even an egg laying animal, that statement is totally false.

Yes, there are good evolutionary reasons why greater intelligence is more common in placental animals - mostly because placental birth is already such a high investment that a parent makes in its offspring, that they are the group of animals that were most likely to further increase their investment in their young by giving them a long training period.  If, in another environment, there was a marsupial or egg laying animal that was also forced, for other reasons, to place a high investment in their young, it might be that they would have formed an even larger brain over time.
« Last Edit: 01/02/2008 02:50:45 by another_someone »
 

lyner

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Communicating With Aliens
« Reply #21 on: 01/02/2008 18:23:39 »
This is all interesting enough but it is not helping us to converge on some sort of final statement on the matter.
The original question involved communication with other lifeforms. That implies Technology, which implies a Need for technology on the part of the lifeform. Trees get no net advantage from developing technology. Neither do cows, or most other herbivores. It is only when you need to be inventive because of competition that you start to develop significant culture and technology. Is it really just chance that made the hominids progress at technology where the apes didn't? Or was it because of their particular niche in the ecology of a couple of million years BC?
We seem to be the 'smartest' so far, in this respect and (post hoc, I admit) we can sort of explain why.  Our technology outshines the technology of any other organism we know, by a huge factor; we are clearly a bit of an exception. What has made us exceptional? Luck; being around at the right time and being around long enough, before some extinction event, to get as far as we have. One hefty asteroid and things could all be back where they started - tiny creatures running about in the forest amongst the ruins of Homo  Sapiens' world.
I, personally, think we are much more likely to come across some humble lifeform, relatively near than end up having a conversation with an advanced one a really long way away.
 

Offline opus

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« Reply #22 on: 01/02/2008 19:31:59 »
Lots of excellent points there anothersomeone- made me think.......
 

another_someone

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« Reply #23 on: 01/02/2008 19:35:05 »
The trouble is (and this is where we got sidetracked before), you are using different concepts, and blithely assuming they all are unavoidably interlinked.

You are talking about intelligence and technology as if they were one and the same thing.  You are also assuming that all technology will inherently lead to telecommunication, or that telecommunication need be associated with other technological advances.

Being 'smart' is about being 'smart' in the context of your environment - there has been much debate about how 'smart' dolphins are (and in fact, arguably, whales and dolphins are capable of telecommunication, if you allow that sending information over hundreds, or thousands, of miles using sound amounts to telecommunication - in an underwater environment, the use of radio would be a technological backward step.

If you want to simply constrain the discussion to radio frequency electromagnetic transmissions (which is all that we seem to be looking for at present), then we should constrain ourselves to that, without asking how intelligent, or 'smart', or even 'civilised' the organism making the transmission is.
 

Offline syhprum

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« Reply #24 on: 02/02/2008 07:24:04 »
The only meaningful conversations across interstellar distances would be between 'aliens' that had a much longer lifetime than us and a vastly different concept of time.
There is a remote chance that if we were in the right position between two systems that were communicating we might eavedrop on such a conversation but would we recognise it as such ? as the data rate would be very low by our standards 
 

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« Reply #24 on: 02/02/2008 07:24:04 »

 

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