Thread: How probable is exointelligence?

Hello Friends:

The Search for Extraterrestrial Intelligence (SETI) incorporates the use of radio telescopes to search for extraterrestrial intelligence. Of course, the extraterrestrial intelligence searched for must have developed technology that sends out radio signals. How likely is it that not only has life originated and evolved beyond the earth but that that life has developed technology much like ours?

Since we have only one known example of a planet that has undergone such evolution, the earth, we must look to this planet for clues to this question. What factors have contributed to the current existence of intelligent life on earth, and does evolution anywhere in the cosmos move in the direction of ever increasing cognitive ability on the part of a sizable number of species?

It seems to me that evolution, at least here on earth, has moved in that direction. Some of the earliest species, one-celled animals, had no brains at all. Multicellular animals much later evolved rudimentary brains that enabled those animals to move about looking for food or avoid being the food of some other animal. Recently in geological history species such as dolphins and primates, including humans, have evolved with elaborate brains that confer survival advantages. Brains are very complex, and evolution would take longer to produce brains with greater complexity.

But must evolution take this course, or could it have been completely different? My guess is that yes, evolution seems destined to move in the direction of ever increasing cognitive abilities on the part of many species. If I'm right, the species on other planets probably have evolved intelligence like ours assuming that there has been enough time for that evolution to progress that far. They may very well have radio-wave technology that could be detected by SETI.

What is the opinion of the biological sciences?

Jagella

I think its ridiculous to think that there is no extraterrestrial life, when there is billions of systems resembling our sun system, and there are million sightings, they cant all be fake, and they are pointing to extraterrestrial intelligence. We are looking for them with satellites and telescopes, and they might be around us already. In my opinion there is no way that they developed similar technologies we have, and they are probably lot more intelligent than us...

The problem is trying to reach a good understanding from a sample size of one.

While a case can be made for intelligent species being an inevitable outcome of evolution the facts seem to suggest otherwise. Millions of species have existed on the Earth. One of these advanced to the point where it could embrace technology. One. Out of millions.

I would say it is almost certainly somewhere between 0 and 100%.

Originally Posted by John Galt

The problem is trying to reach a good understanding from a sample size of one.

While a case can be made for intelligent species being an inevitable outcome of evolution the facts seem to suggest otherwise. Millions of species have existed on the Earth. One of these advanced to the point where it could embrace technology. One. Out of millions.

This leads to a question, what are your thoughts about competition between different species? Is it possible some species evolved in ways where it was specifically more advantageous to not be in a competitive role with a more apt rival?

Originally Posted by John Galt

The problem istrying to reach a good understanding from a sample size ofone.

That's for sure. Since we know of onlyone instance of a planet with intelligent life, we are forced tospeculate.

Originally Posted by John Galt

While a casecan be made for intelligent species being an inevitable outcome ofevolution the facts seem to suggest otherwise. Millions of specieshave existed on the Earth. One of these advanced to the point whereit could embrace technology. One. Out of millions.

Actually, other species including chimps and octopuses have been known to use tools not to mention hominid species that make up the human family tree. Also, although only one species on earth has ever evolved radio technology, that species numbers in the billions, has adapted to life throughout much of the earth, and dominates the planet. It sure seems that evolution results in cognitive ability given enough time.


But thanks for the healthy dose of skepticism. I believe more research may be needed to answer the question of how probable intelligent life is here on earth and beyond it.


Jagella

Originally Posted by stander-j

Is it possible some species evolved in ways where it was specifically more advantageous to not be in a competitive role with a more apt rival?

Of course. If competition can be avoided, it may be to your advantage. If you and a more intelligent, charming, and attractive man are attempting to woo a woman, getting him out of the picture will increase your chances of passing down your DNA.

Jagella

Originally Posted by stander-j

This leads to a question, what are your thoughts about competition between different species? Is it possible some species evolved in ways where it was specifically more advantageous to not be in a competitive role with a more apt rival?

Not only is it common for evolution to work towards evading competition, but it is almost universal (here on Earth). This is why we talk of organisms occupying a specific ecological niche. By being extremely well adapted to exploiting a specific mode, they avoid the competition from other organisms that might do better in other situations.

On intelligent life off Earth, we must also consider the Fermi Paradox.
Fermi paradox - Wikipedia, the free encyclopedia

Originally Posted by Jagella

Actually, other species including chimps and octopuses have been known to use tools not to mention hominid species that make up the human family tree. Also, although only one species on earth has ever evolved radio technology, that species numbers in the billions, has adapted to life throughout much of the earth, and dominates the planet. It sure seems that evolution results in cognitive ability given enough time.

Your 'evidence' can also be used for the counter argument. although many species have developed very primitive technology only one has 'embraced' technology to that extent it is essential to its existence. The evolutionary pathway that led to us was contingent upon an unknown number of singular events. There is every reason to suspect these are vanishingly rare since only one species has ever made this transition.

Originally Posted by John Galt

The problem is trying to reach a good understanding from a sample size of one.

The best way is to look for causality in the results of that sample. If we can assume that the fundamental natural laws are the same throughout the universe, then we can work from there.

While a case can be made for intelligent species being an inevitable outcome of evolution the facts seem to suggest otherwise. Millions of species have existed on the Earth. One of these advanced to the point where it could embrace technology. One. Out of millions.

I think of it like this: life naturally tends to move toward complexity. Life's competition is just like the field of cryptography. One side devises a more sophisticated cipher, the other devises a more sophisticated way of cracking ciphers. So the first side has to up its complexity. The inevitable ending point is high intelligence. It's not really and ending point, .... exactly, but the first species to get there begins evolving faster than its peers (because evolution of ideas goes faster than genetic evolution - the host doesn't have to die.)


Probably the first life form stored its hydrocarbons by just dropping them, in simple form, on the ground around it. No need to protect them from anyone. As the population increased, they started stealing from each other, so sooner or later some of them started trying to devise better "locks" for their storage, and protecting them. Complicated proteins start to form in order to achieve that elusive situation where the owner can get to their hydrocarbons, but nobody else can..... just like cryptography. Do you see how, in a situation like that, the complexity could start increasing to no upper end? But there is an end, because when intelligence arrives it replaces the Darwinistic selection process with something new. We're back to just one life form again. It solidifies its lead very quickly over the others, and has only itself to compete with again.

My personal theory is that one of three things happens next. (In this case there's a sample set of zero, because we're not quite there yet.) Either

1) - That species wipes itself out completely, leaving nature to start again from scratch.

or

2) - Achieves technological immortality and stops bearing new offspring, completely and utterly ending Darwinistic selection forever in its history.

or

3) - Simply starts limiting its population on purpose, even without technological immortality, and makes life for the few who do live on its planet so easy that no selection pressures exist, which also stops the Darwinistic selection process.

In all three options the process ends. In #1 it starts over. In #2, and #3 it simply ends and we forget about it. There is no option for it to continue.

If I'm right about this, and if it's kind of a natural law of sorts, then nearly every planet that gets life going on it for a long enough time will eventually arrive at one of those three destinations. Anyone alien who falls into category #1 is likely to be dead before we meet them (too small a window). Any alien from options #2 or #3 would find us too savage to be worth the trouble of trying to open relations with us, though they may stop by from time to time to observe us out of curiosity.

I think of it like this: life naturally tends to move toward complexity.

You need to demonstrate that. You cannot just assume it, unless you are willing to categorise the argument that follows as mere speculation.

Originally Posted by John Galt

Originally Posted by Jagella

Actually, other species including chimps and octopuses have been known to use tools not to mention hominid species that make up the human family tree. Also, although only one species on earth has ever evolved radio technology, that species numbers in the billions, has adapted to life throughout much of the earth, and dominates the planet. It sure seems that evolution results in cognitive ability given enough time.

Your 'evidence' can also be used for the counter argument. although many species have developed very primitive technology only one has 'embraced' technology to that extent it is essential to its existence. The evolutionary pathway that led to us was contingent upon an unknown number of singular events. There is every reason to suspect these are vanishingly rare since only one species has ever made this transition.

Trans-generation memory is the trait at the core of it all. We don't just use tools by instinct (or at least our level of instinctive tool use doesn't greatly exceed that of a chimp). It can also be described as the trait of "super fast evolution", at least as it pertains to our minds and survival skills. Other animals evolve survival skills as genetically imprinted instinct .... a much slower process.

It stands to reason that the first species to get there would begin to progress so rapidly that it quickly out competes all the others, vanquishing them before they ever have the chance.

Originally Posted by John Galt

I think of it like this: life naturally tends to move toward complexity.

You need to demonstrate that. You cannot just assume it, unless you are willing to categorise the argument that follows as mere speculation.

I'll give it a shot.

1) - Cryptography is attempting to achieve the same basic task as life, in that a cryptographer wants to store information in a form where they can get at it, but nobody else can, while life is trying to store hydrocarbons in a form where it can get at it, but nobody else can.

2) - The task of storing something in a form where you can get at it but nobody else can has given rise to quite a lot of complexity in a fairly short time span since the discipline of cryptography emerged.

3) - This method (of competing by increasing complexity) appears to be the only strategy that works.

Therefore:

4) - Any entity that is attempting to be successful in this type of competition, and wins, would used that strategy. (Whether the entity is intelligent or not.)

How likely is it that not only has life originated and evolved beyond the earth but that that life has developed technology much like ours?

I think its likely that somewhere in the universe among trillions of planets, at some point in time in the last billion years, several civilization used radio for a certain number of years.

What factors have contributed to the current existence of intelligent life on earth

The diversification advantage, the colony mechanism and multi-cellular advantages, and of these advantages is the advantage to be aware of the environment which requires to be more precise the processing of signals.
Keep in mind that single cell organism are still very numerous on earth. Animals have a different set of advantages and disadvantages, among the advantage is the ability to perceive a food source or a danger, and to move towards that food source or away from the danger. Single cell organism have other advantages that offset their reduced perception. Also note that our cells are not aware nor can they see anything, we, that is the interaction between those cells, are aware of the objects that surrounds us, and this awarness is due to re-cognition of patterns, patterns that are a representation/construct of the exterior reality.

and does evolution anywhere in the cosmos move in the direction of ever increasing cognitive ability on the part of a sizable number of species?

Probably imo given enough time and room for diversity.


Though experiment: Lets say life started 80 million years ago on a planet thats 10 light years away, and that it followed the exact same pattern as on earth, we could expect to detect radio waves in a few billion years from now. Except will humans still be around then? If we dont expand into a space faring civilization I have doubts that we would still be around for some reason or another. If all thats left for some reason are underground microbes they wont know that other planet uses radio waves.

Originally Posted by John Galt

Your 'evidence'can also be used for the counter argument. although many species havedeveloped very primitive technology only one has 'embraced'technology to that extent it is essential to its existence. Theevolutionary pathway that led to us was contingent upon an unknownnumber of singular events. There is every reason to suspect these arevanishingly rare since only one species has ever made thistransition.

Your point is well taken, John, but Ithink you may be a bit shortsighted. With enough time, othertool-using species might very well start to depend on their tools forsurvival especially if their tools enable them to adapt to placesbeyond their home range.


Jagella

Nobody knows exactly how life starts, so it's a complete wild guess. Not even worth discussing.

Originally Posted by Jagella

Your point is well taken, John, but Ithink you may be a bit shortsighted. With enough time, othertool-using species might very well start to depend on their tools forsurvival especially if their tools enable them to adapt to placesbeyond their home range.

Well they might do so. But quite complex mental equipment has been around for a couple of hundred million years and very complex brains for at least fifty million years and yet we see only a single species which has embraced technology. If this were so likely it sems it should have happened earlier or more than once.

My central point - and the one made by Harold - is that we simply don't know and currently don't have enough information to make an informed decision. I suggest rather than being shortsighted I am seeing microscopically, macroscopically and across the entire EM range, looking for data that would enhance our understanding. I rule out nothing. I simply refuse to even reach a provisional conclusion. It wouldn't be scientific.

Originally Posted by Harold14370

Nobody knows exactly how life starts, so it's a complete wild guess. Not even worth discussing.

Yeah, we don't know much about how abiogenesis works.

However we do know quite a bit about how life evolves once it has started. That's pretty well documented stuff. And intelligence has actually appeared in a fairly wide variety of species. Crows and ravens, for example, which aren't even mammals, have done well on quite a few intelligence tests.

http://en.wikipedia.org/wiki/Corvidae#Intelligence

http://news.nationalgeographic.com/news/2006/06/060606-crows.html


Since birds are descendants of the dinosaurs, that indicates that, if not for their (near) extinction event, it's quite possible that they would have eventually arrived where we are now.

Add to that the cephalopods (squids and octopi) which are even further from humans biologically, but have evolved quite high levels of intelligence.

Originally Posted by icewendigo

Though experiment: Lets say life started 80 million years ago on a planet thats 10 light years away, and that it followed the exact same pattern as on earth, we could expect to detect radio waves in a few billion years from now. Except will humans still be around then? If we dont expand into a space faring civilization I have doubts that we would still be around for some reason or another. If all thats left for some reason are underground microbes they wont know that other planet uses radio waves.

Yes, this problem of time differentials between the eras of the existence of intelligent species in different parts of the cosmos makes the question of intelligent life in the universe even harder to answer. Not only are we separated by space, but we are separated by time. We may have missed that civilization ten light years away if it perished ten years before we developed the radio technology to pick up signals from their planet. The last signals would have been missed by us right before we started to listen!

Jagella

Originally Posted by John Galt

Originally Posted by Jagella

Your point is well taken, John, but Ithink you may be a bit shortsighted. With enough time, othertool-using species might very well start to depend on their tools forsurvival especially if their tools enable them to adapt to placesbeyond their home range.

Well they might do so. But quite complex mental equipment has been around for a couple of hundred million years and very complex brains for at least fifty million years and yet we see only a single species which has embraced technology. If this were so likely it sems it should have happened earlier or more than once.

I can think of some reasons for there being only one radio-wave-technology producing species here on earth aside from such a species being unlikely to evolve. The earth has a long life ahead of it--billions of years--and I think there may be a chance of more technological civilizations ahead created by other species. We may simply be the first such species on earth to evolve advanced technology.

Another perhaps disturbing reason is that homo sapiens has a habit of wiping out other species that may also have a chance of developing advanced technologies. Some paleontologists think we may be responsible for the extinction of the neanderthals by killing them off. If neanderthals had survived, I think its very possible they would have advanced technology by now.

Originally Posted by John Galt

My central point - and the one made by Harold - is that we simply don't know and currently don't have enough information to make an informed decision. I suggest rather than being shortsighted I am seeing microscopically, macroscopically and across the entire EM range, looking for data that would enhance our understanding. I rule out nothing. I simply refuse to even reach a provisional conclusion. It wouldn't be scientific.

Well, scientists often speculate if there is a dearth of evidence. That's OK as long as we recognize we are only engaging in speculation. Speculation can lead to some educated guesses that might be tested some day.

Jagella

The Drake Equation was created to help estimate the number of detectable extraterrestrial civilizations in the Milky Way galaxy. The eponymous Frank Drake's parameters were plugged in to the equation and returned N = 10 as the approximation. However, many of his peers were inclined to believe that the values he used for each variable in the equation (with one or two exceptions) were high estimates, which would increase the value of the approximation as well.

While I can fully empathize with astronomers (and amateurs) for wanting to quantify the probability of encountering extraterrestrial life, I take exception to the Drake Equation because its variables are based on assumptions that are very narrow and arbitrary with respect to the scope of the universe. Due to our extremely limited knowledge and understanding about the universe and abiogenesis, I think that most (if not all) attempts to apply conventional statistics and probability to life outside our own planet will be inaccurate, and that speculation about extraterrestrial life serves no practical purpose - only entertainment. I wish this wasn't the case. This is a topic that I (along with so many others) am painfully curious about, but it seems to me that the only assumption we can even come close to making safely is that life evolving elsewhere is probable by merit of the universe being as large and full of matter/energy as it is.

If anyone else has some insights that are more optimistic or different than mine, I would be interested to hear them.

Originally Posted by Saturn

If anyone else has some insights that are more optimistic or different than mine, I would be interested to hear them.

Perhaps one reason for optimism is that the more we learn about the universe, the less special we and our planet turn out to be. It wasn't that long ago that Copernicus revealed that the cosmos is more easily thought of as not being geocentric. The earth is just another planet in the solar system. The sun is just another star in an immense galaxy, and the Milky Way is merely another galaxy among billions. Since we are not special, then we are probably not alone.

Originally Posted by Jagella

Perhaps one reason for optimism is that the more we learn about the universe, the less special we and our planet turn out to be. It wasn't that long ago that Copernicus revealed that the cosmos is more easily thought of as not being geocentric. The earth is just another planet in the solar system. The sun is just another star in an immense galaxy, and the Milky Way is merely another galaxy among billions. Since we are not special, then we are probably not alone.

Agreed. Given the vastness of outer space and our solar system's relatively standard existence in it, I also find it difficult to believe that the conditions for life are unique to us. To clarify something I said earlier, I don't believe that speculating about the existence of extraterrestrial life is pointless - only that it is impractical to speculate about its qualities and to assume that it shares any characteristics with life from Earth. We know for certain that the life here develops in accordance with its environment, and since we have NO idea what environments that other life in the universe may have evolved in are like, we have to be prepared to accept that other life may not even remotely resemble anything that we would recognize as "alive" (that is, assuming life elsewhere evolves in a similar manner as life does here - not an unreasonable assertion, I don't think).

That being said, I still find it to be an interesting thought exercise to consider how life may have evolved in different locations with different initial conditions.

Originally Posted by Saturn

We know for certain that the life here develops in accordance with its environment, and since we have NO idea what environments that other life in the universe may have evolved in are like, we have to be prepared to accept that other life may not even remotely resemble anything that we would recognize as "alive" (that is, assuming life elsewhere evolves in a similar manner as life does here - not an unreasonable assertion, I don't think).

That being said, I still find it to be an interesting thought exercise to consider how life may have evolved in different locations with different initial conditions.

There are some constants. If Darwinistic selection is occurring in order to allow evolution, then the life forms are part of each others' environments. They should be at war against each other, and the most complex life forms tend to win those wars. Or I guess that depends how you measure "Winning". Cockroaches aren't overly complex I guess. In Darwinistic selection, the winners are the ones who continue to the next round.


As mentioned, the first being to evolve trans-generation memory, and cognitive problem solving ability enters into a new dimension of self improvement where the improvements are happening so rapidly, literally millions of times faster than they are for the species that only experience genetic improvement, that the competition isn't really a "competition" anymore. Unless by pure random chance, two or more species got there at exactly the same epoch in history, that first species would shore up its position so well that no other species ever has the chance to join it.

Hence, we should expect to only ever find exactly one intelligent species capable of producing radio waves on any planet.

Originally Posted by Saturn

it seems to me that the only assumption we can even come close to making safely is that life evolving elsewhere is probable by merit of the universe being as large and full of matter/energy as it is.

No, that's not safe to assume. What ever number you speculate is the probability of life evolving, I can speculate one that is a few orders of magnitude smaller.

Originally Posted by Saturn

To clarifysomething I said earlier, I don't believe that speculating about theexistence of extraterrestrial life is pointless - only that it isimpractical to speculate about its qualities and to assume that itshares any characteristics with life from Earth. We know for certainthat the life here develops in accordance with its environment, andsince we have NO idea what environments that other life in theuniverse may have evolved in are like, we have to be prepared toaccept that other life may not even remotely resemble anything thatwe would recognize as "alive" (that is, assuming lifeelsewhere evolves in a similar manner as life does here - not anunreasonable assertion, I don't think).


That being said, I still find it to bean interesting thought exercise to consider how life may have evolvedin different locations with different initial conditions.

I believe our own solar system provides some significant clues about life and what planets it may exist on. As far as we know, earth is the only planet on which life originated and evolved. That includes the nine planets in the solar system and their moons. It seems to me that since there is evidently no life on the other planets and any of the moons in the solar system, then life may be rather rare in the cosmos. Hot temperatures and cold temperatures may make life impossible. A lack of a solid surface may make life impossible. Liquid water may well be vital to the existence of life—no liquid water, no life.


So why is earth so full of life in an otherwise dead or nearly dead solar system? Some people argue that we live on a “privileged planet” upon which conditions are “just right.” We live in what some call a Goldilocks zone that isn't too hot or too cold. Thanks to the moon's gravity, our planet is tilted in such a way as to maintain reasonably stable temperatures on its surface. Jupiter acts like a giant vacuum cleaner sucking up most of the asteroids and comets that might wreak havoc with earth by colliding with it.


I think there may be some merit to this argument. After all, if life is so abundant in the cosmos, then why does it seem so rare right here at home?


Jagella

Originally Posted by kojax

the competition isn't really a "competition" anymore. Unless by pure random chance, two or more species got there at exactly the same epoch in history, that first species would shore up its position so well that no other species ever has the chance to join it.

Hence, we should expect to only ever find exactly one intelligent species capable of producing radio waves on any planet.

Kojax

Have you ever encountered the science fiction books written by David Brin?
He introduces a concept he calls 'uplift'. In this, a dominant intelligent species seeks out what he calls 'presentient' animals and genetically alters them to make them intelligent. They also have genes inserted to ensure love and loyalty to the dominant species. The new intelligence then becomes servant to the older.

While this is fiction, I see nothing in theory to prevent it ever happening. Perhaps one day, humans will 'uplift' chimps, gorillas, orang utan etc, and make them intelligent. Then there will be more than one intelligent and technological species on Earth.

Originally Posted by kojax

There are some constants. If Darwinistic selection is occurring in order to allow evolution, then the life forms are part of each others' environments. They should be at war against each other, and the most complex life forms tend to win those wars. Or I guess that depends how you measure "Winning". Cockroaches aren't overly complex I guess. In Darwinistic selection, the winners are the ones who continue to the next round.

I am inclined to agree that there may be some constants if Darwinistic selection applies. However, I also think it's possible that there would be an absence of competition and "war" amongst the different species, as suggested by skeptic in reference to David Brin's books. Whatever the evolutionary reason may be, some species could survive/thrive by forming advanced symbiotic relationships with each other instead of competing for dominance and resources, or the intellectually superior species may evolve the capacity to appreciate the long term (potential) gain by cultivating intelligence in less advanced species, instead of merely preying on them to satisfy primal needs. Perhaps there would even be some who follow some kind of a "moral" imperative to protect and look after less advanced species for no immediate or direct gain. That's not dissimilar from the work done by naturalists right here on planet Earth. See what I mean? Interesting thought exercise.

Originally Posted by Harold14370

Originally Posted by Saturn

it seems to me that the only assumption we can even come close to making safely is that life evolving elsewhere is probable by merit of the universe being as large and full of matter/energy as it is.

No, that's not safe to assume. What ever number you speculate is the probability of life evolving, I can speculate one that is a few orders of magnitude smaller.

That's just it, I don't assign probability to life evolving. That has been the entire point of everything I've posted in this thread so far - that we lack sufficient information to accurately quantify it. The assumption is in reference to mathematics, which has been used to prove the existence of something without contradicting mathematical logic. It is a weak assumption...hence my phrase of choice "the only assumption we can even come close to making safely".

Originally Posted by Jagella

I believe our own solar system provides some significant clues about life and what planets it may exist on. As far as we know, earth is the only planet on which life originated and evolved. That includes the nine planets in the solar system and their moons. It seems to me that since there is evidently no life on the other planets and any of the moons in the solar system, then life may be rather rare in the cosmos. Hot temperatures and cold temperatures may make life impossible. A lack of a solid surface may make life impossible. Liquid water may well be vital to the existence of life—no liquid water, no life.


So why is earth so full of life in an otherwise dead or nearly dead solar system? Some people argue that we live on a “privileged planet” upon which conditions are “just right.” We live in what some call a Goldilocks zone that isn't too hot or too cold. Thanks to the moon's gravity, our planet is tilted in such a way as to maintain reasonably stable temperatures on its surface. Jupiter acts like a giant vacuum cleaner sucking up most of the asteroids and comets that might wreak havoc with earth by colliding with it.


I think there may be some merit to this argument. After all, if life is so abundant in the cosmos, then why does it seem so rare right here at home?


Jagella

It's hard to say exactly why Earth's conditions were the most optimal of the planets for life to evolve on (as opposed to one of the other terrestrial planets that have different temperatures, compositions, etc but are also still protected by Jupiter), but I agree with you that it is a good place to start when considering where else we may find life. It's also important to remember that other planets in the solar system may have been more hospitable to life in the past than they are now. It will be really great when we have the technology to explore the solar system. Conducting surveys of other celestial objects nearby may yield more information as to what this place was like in its nascent (and intermediary, for that matter) stages. If we are really lucky, we may find some clues to the genesis of life, or some evidence that would confirm/refute the presence of life (current or not) on any other object in this solar system. Until then, we can only speculate. Are you familiar with theories that suggest life on Earth was transplanted here? Lack of physical evidence aside, what is your opinion of such theories?

Originally Posted by Saturn

Are you familiarwith theories that suggest life on Earth was transplanted here? Lackof physical evidence aside, what is your opinion of suchtheories?

Yes, I'm familiar with the idea of panspermia. I'd say that these theories are credible considering that about twelve years ago the scientific community discovered an asteroid from Mars that was initially thought to include fossilized evidence for martian microorganisms. If we wish to know how life got started anywhere in the cosmos, though, then panspermia won't help much because it only tells us where life came from rather than how it originated.


Coincidentally, I was just recently thinking that we humans may try using panspermia or microorganisms from the earth to seed other planets and moons. That way we might be able to determine which planets or moons can harbor life even if life did not originate on those worlds. Such an experiment may help us understand the conditions necessary for life to exist.


Jagella

Originally Posted by Jagella

Originally Posted by Saturn

Are you familiarwith theories that suggest life on Earth was transplanted here? Lackof physical evidence aside, what is your opinion of suchtheories?

Yes, I'm familiar with the idea of panspermia. I'd say that these theories are credible considering that about twelve years ago the scientific community discovered an asteroid from Mars that was initially thought to include fossilized evidence for martian microorganisms. If we wish to know how life got started anywhere in the cosmos, though, then panspermia won't help much because it only tells us where life came from rather than how it originated.


Coincidentally, I was just recently thinking that we humans may try using panspermia or microorganisms from the earth to seed other planets and moons. That way we might be able to determine which planets or moons can harbor life even if life did not originate on those worlds. Such an experiment may help us understand the conditions necessary for life to exist.


Jagella

thats some smart thinking there

Originally Posted by Jagella

Originally Posted by Saturn

To clarifysomething I said earlier, I don't believe that speculating about theexistence of extraterrestrial life is pointless - only that it isimpractical to speculate about its qualities and to assume that itshares any characteristics with life from Earth. We know for certainthat the life here develops in accordance with its environment, andsince we have NO idea what environments that other life in theuniverse may have evolved in are like, we have to be prepared toaccept that other life may not even remotely resemble anything thatwe would recognize as "alive" (that is, assuming lifeelsewhere evolves in a similar manner as life does here - not anunreasonable assertion, I don't think).


That being said, I still find it to bean interesting thought exercise to consider how life may have evolvedin different locations with different initial conditions.

I believe our own solar system provides some significant clues about life and what planets it may exist on. As far as we know, earth is the only planet on which life originated and evolved. That includes the nine planets in the solar system and their moons. It seems to me that since there is evidently no life on the other planets and any of the moons in the solar system, then life may be rather rare in the cosmos. Hot temperatures and cold temperatures may make life impossible. A lack of a solid surface may make life impossible. Liquid water may well be vital to the existence of life—no liquid water, no life.


So why is earth so full of life in an otherwise dead or nearly dead solar system? Some people argue that we live on a “privileged planet” upon which conditions are “just right.” We live in what some call a Goldilocks zone that isn't too hot or too cold. Thanks to the moon's gravity, our planet is tilted in such a way as to maintain reasonably stable temperatures on its surface. Jupiter acts like a giant vacuum cleaner sucking up most of the asteroids and comets that might wreak havoc with earth by colliding with it.


I think there may be some merit to this argument. After all, if life is so abundant in the cosmos, then why does it seem so rare right here at home?


Jagella

Very good observation. Life on earth was created and evolved from the conditions and materials on this planet. Life on earth is suited for earth, not by chance or cosmic luck but, because energy and matter created life and that life came into existence by, and conformed to, the conditions and materials in, on and around planet earth. That does not make our patch and surroundings in space a Goldilocks zone, it only makes it our Goldilocks zone.

I suspect that we are either all alone or life forms just about everywhere, while a rather large range in veritable stability allows more life forms to be created and/or evolve.

Originally Posted by skeptic

Originally Posted by kojax

the competition isn't really a "competition" anymore. Unless by pure random chance, two or more species got there at exactly the same epoch in history, that first species would shore up its position so well that no other species ever has the chance to join it.

Hence, we should expect to only ever find exactly one intelligent species capable of producing radio waves on any planet.

Kojax

Have you ever encountered the science fiction books written by David Brin?
He introduces a concept he calls 'uplift'. In this, a dominant intelligent species seeks out what he calls 'presentient' animals and genetically alters them to make them intelligent. They also have genes inserted to ensure love and loyalty to the dominant species. The new intelligence then becomes servant to the older.

While this is fiction, I see nothing in theory to prevent it ever happening. Perhaps one day, humans will 'uplift' chimps, gorillas, orang utan etc, and make them intelligent. Then there will be more than one intelligent and technological species on Earth.

Originally Posted by Saturn

I am inclined to agree that there may be some constants if Darwinistic selection applies. However, I also think it's possible that there would be an absence of competition and "war" amongst the different species, as suggested by skeptic in reference to David Brin's books. Whatever the evolutionary reason may be, some species could survive/thrive by forming advanced symbiotic relationships with each other instead of competing for dominance and resources, or the intellectually superior species may evolve the capacity to appreciate the long term (potential) gain by cultivating intelligence in less advanced species, instead of merely preying on them to satisfy primal needs. Perhaps there would even be some who follow some kind of a "moral" imperative to protect and look after less advanced species for no immediate or direct gain. That's not dissimilar from the work done by naturalists right here on planet Earth. See what I mean? Interesting thought exercise.

If you think about it, to a lesser degree this actually has happened in human evolution. We adopted dogs, horses, mules, and some hunting birds as pets that aided us for a long time in our survival. We didn't deliberately impart them with intelligence, because we didn't know how, but we certainly weren't in competition with them. Even cows and chickens enjoy a somewhat symbiotic relationship with us, though it gets a bit less friendly for them there around the end of their life....

The main problem for these pets is we keep developing mechanical/computer technology that can do their job better than they can. I'm sure we'll even make our own selves obsolete soon. However, I see no good reason we couldn't have discovered Darwinism before modern technology. If we had practiced targeted breeding on our dogs, horses.... etc then maybe we could have gotten them up to our level of IQ before machines stepped in to replace them.

It's an interesting idea anyway. I'll look Mr. Brin up next time I'm at Powells Books.

Originally Posted by gonzales56

Very good observation. Life on earth was created and evolved from the conditions and materials on this planet. Life on earth is suited for earth, not by chance or cosmic luck but, because energy and matter created life and that life came into existence by, and conformed to, the conditions and materials in, on and around planet earth. That does not make our patch and surroundings in space a Goldilocks zone, it only makes it our Goldilocks zone.

Then why are there no Martians enjoying their own Goldilocks zone? Why no Venutions enjoying those lead-melting temperatures? At least here in our own solar system it appears that there is but one Goldilocks zone--the one the earth orbits in. If you'd like to improve your case, then you'll need to cite instances of life existing in conditions like those on other planets.

To do so, I'll recommend again that we seed Mars and some of the moons of Jupiter and Saturn with some of our hardiest microorganisms. If any of them can survive, then we have evidence that other planets or moons can support life.

Originally Posted by gonzales56

I suspect that we are either all alone or life forms just about everywhere, while a rather large range in veritable stability allows more life forms to be created and/or evolve.

I think that life may be fairly common in the cosmos, but intelligent life is comparatively rare.

Jagella

Intelligent life is fairly rare on Earth.

Originally Posted by Jagella

Then why are there no Martians enjoying their own Goldilocks zone? Why no Venutions enjoying those lead-melting temperatures? At least here in our own solar system it appears that there is but one Goldilocks zone--the one the earth orbits in. If you'd like to improve your case, then you'll need to cite instances of life existing in conditions like those on other planets.

To do so, I'll recommend again that we seed Mars and some of the moons of Jupiter and Saturn with some of our hardiest microorganisms. If any of them can survive, then we have evidence that other planets or moons can support life.

I think that life may be fairly common in the cosmos, but intelligent life is comparatively rare.

Jagella

If there is no life that was created and developed on Mars then we are more than likely going to be it IMO. If life is a random reality of energy and matter then all energy and matter should be able to combine in a way which produces life, and that should occur just about everywhere and often enough to where it is abundant IMO.

We really don't have enough data to estimate the probablity of life much less intelligence. We have a sample size of only one for planets we have explored that both have life and have intelligent life. So far as we know the correlation of life to intelligence is 100%. All the planets we know of that have life also have intelligent life. But we also know that for the majority of its biological history Earth did not have intelligent life. So clearly simple math will lead us astray. But what other tool can we use to answer a question of probablity?

Latest astromomical theory suggests that there are vastly more planets than stars and the number of stars is very, very large. So the number of possible homes for life is nearly infinite yet we can only claim to have explored, even using the term loosly, 4 worlds. Of Earth, Venus, Luna, and Mars it appears only Earth has life. That gives a chance of one in 4 of the "goldilocks zone" planets having life. Our sample size is still to low.

And within the past month or so, two pieces of research have emerged, one tending to push up the estimate of possible habitable planets - the other tending to push it down.

On the one hand researchers are suggesting that habitable zones much larger than previously thought may exist around M-type stars (red dwarfs). See here. (For some reason this link isn't working, although I can access it just fine outwith this post. The paper is Cuntz, M. et al "Habitability of super-Earth planets around main-sequence stars including red giant branch evolution: models based on the integrated system approach." International Journal of Astrobiology 11 (1): 15–23 (2012))

On the other hand other researchers report the possibility that planets in the Goldilocks zone may be stripped of their water and become like Venus. See here.

Originally Posted by Sealeaf

what other tool can we use to answer a question of probablity?

So the number of possible homes for life is nearly infinite yet we can only claim to have explored, even using the term loosly, 4 worlds. Of Earth, Venus, Luna, and Mars it appears only Earth has life. That gives a chance of one in 4 of the "goldilocks zone" planets having life. Our sample size is still to low.

If other life was probable, wouldn't it also be probable that there are 10,000's, 100,000's, 1,000,000's, if not billions or trillions of life forms that are super intelligent, been around for millions or billions of years and are so far advanced that it would make our heads spin (immortal, wormholes, time travel, etc.)?

Where are these millions, billions or trillions of different super species at? Hiding? Being very quite? Not moving?

If "Probability" is going to be used to suggest or sell life as being abundant throughout the universe, then that same probability predicts that there are million, billions or even trillions of extremely advanced life forms that have been around for millions or billions of years.

Every inch of the universe (including our little section), according to the probabilities put forth by these theories, should at least be littered with the signals and sounds of billions or trillions of these super intelligent species.

Heck, according to probability, these species should have already been vacationing in Florida, right?

The entire "probability" thing concerning life in the universe should be thrown out with the bath water IMO. It shoots itself in the foot.

Originally Posted by gonzales56

The entire "probability" thing concerning life in the universe should be thrown out with the bath water IMO. It shoots itself in the foot.

Only because we are currently using a sample size of one for a situation where we don't even understand the constraints on the inputs.

[QUOTE=gonzales56;316940]

Originally Posted by Sealeaf

Where are these millions, billions or trillions of different super species at? Hiding? Being very quite? Not moving?

I think you underestimate the problem of interstellar travel or communication. The galaxy could be teeming with intelligent life, but we may never know about it because it is so far away. I think it may well be a moot point.

Originally Posted by Harold14370

I think you underestimate the problem of interstellar travel or communication. The galaxy could be teeming with intelligent life, but we may never know about it because it is so far away. I think it may well be a moot point.

I do not underestimate anything. If there was just one intelligent life form in our own galaxy that figured out how to travel half the speed of light, it would only take them, their ships or their machines 200,000 years to go from one side of our galaxy to the other side. In fact, it wouldn't be hard for them to arrive at and utilize every useful or interesting planet in our entire galaxy within, lets say, a million years or so.

Communication is also not an excuse or a restriction. It would only take 1 intelligent life form in our galaxy to have broadcasted radio waves for the last 100,000 years for that signal to be heard throughout our entire galaxy.

Now just imagine what it would be like if our galaxy was teaming with intelligent life forms.

gonzales is correct.
Even at one tenth light speed, it would take only a million years to fully colonise the galaxy. Against a background of the 8 billion years that the galaxy has been here, if alien intelligent life was common, it would already be here on Earth, and humanity would probably never have evolved.

Originally Posted by skeptic

gonzales is correct.
Even at one tenth light speed, it would take only a million years to fully colonise the galaxy. Against a background of the 8 billion years that the galaxy has been here, if alien intelligent life was common, it would already be here on Earth, and humanity would probably never have evolved.

"Even" at one tenth the speed? That requires an enormous amount of energy.
Interstellar travel - Wikipedia, the free encyclopedia

Accelerating one ton to one-tenth of the speed of light requires at least 450 PJ or 4.5 ×10¹⁷ J or 125 billion kWh, not accounting for losses. This energy has to be carried along^{[citation needed]}, as solar panels do not work far from the Sun and other stars.

That's about the energy of the biggest nuclear weapon ever detonated.

Harold

As I have said before, this is not my idea. This comes from a SciAm article over 10 years ago, written by two NASA scientists on the topic of interstellar travel. They claim that humanity is likely to be able to travel between stars within 500 to 1000 years at a speed of 0.1 c to 0.2 c. I am not a rocket scientist, but they are.

I know I will get called a crackpot, but I have seen a UFO fairly up close, and can tell you that it looked like nothing humanly possible. They are already here. By the way, it's not April Fool's here yet, so I'm serious.

Originally Posted by Harold14370

Originally Posted by skeptic

gonzales is correct.
Even at one tenth light speed, it would take only a million years to fully colonise the galaxy. Against a background of the 8 billion years that the galaxy has been here, if alien intelligent life was common, it would already be here on Earth, and humanity would probably never have evolved.

"Even" at one tenth the speed? That requires an enormous amount of energy.
Interstellar travel - Wikipedia, the free encyclopedia

Accelerating one ton to one-tenth of the speed of light requires at least 450 PJ or 4.5 ×10¹⁷ J or 125 billion kWh, not accounting for losses. This energy has to be carried along^{[citation needed]}, as solar panels do not work far from the Sun and other stars.

That's about the energy of the biggest nuclear weapon ever detonated.

You ever hear of Project Orion? Thermonuclear propulsion has the ability to reach about 10% the speed of light. We have the technology to accomplish that now but, that is irrelevant. If probability is used to try and dictate that the universe is teeming with life, then that life has to include intelligent life that is far more advanced than we are, and they would not be bound by our own current technologies and/or our own unwillingness at this point in time to explore/travel space.

This is how and why the probability argument concerning life in the universe shoots itself in the foot. It is impossible to have it both ways. Someone cant claim that life has to be abundant outside of earth due to the amount of space and material while also arguing that life outside of earth is someway or somehow incapable of achieving what we wont, cant or have not done.

"Life is there but, it is dumb". I get it... ...... But the very same logic (which might in fact just be madness) that makes one believe that life is abundant throughout the universe also tells us that massive amounts of that life would be highly intelligent and highly advanced. Now, we have to travel to find dumb/simple life forms but, we don't have to travel to see or hear highly intelligent and highly advanced life forms.... Intelligent ETs are the forms of life we should discover first and should have already discovered but, we have not seen or heard from them (as far as we know). That fact is not encouraging IMO.