141 replies to this topic

[BillP]

From the article link below.  Interesting.

 

"Our evolutionary history shows that many key adaptations – not just intelligence, but complex animals, complex cells, photosynthesis, and life itself – were unique, one-off events, and therefore highly improbable."

 

"Surprisingly, many critical events in our evolutionary history are unique and, probably, improbable."

 

"There are places where evolution repeats, and places where it doesn’t. If we only look for convergence, it creates confirmation bias. Convergence seems to be the rule, and our evolution looks probable. But when you look for non-convergence, it’s everywhere, and critical, complex adaptations seem to be the least repeatable, and therefore improbable."

 

https://theconversat...universe-124706

 

[Shorty Barlow]

This is a bit of a numbers game as I see it, but without enough information. Convergent evolution probably isn't an inevitability, but it is a distinct possibility, and has happened here. A lot of astronomers now seem to believe there are far too many filters to make a Drake Equation scenario of thousands of galactic civilisations viable in a galaxy the size of the Milky Way. So we could very well be the most advanced (or only) life in our galaxy. Larger galaxies may have slightly more chances at producing advanced life or even advanced civilisations. I don't know anything about statistics, but maybe a galaxy twice the size of the Milky Way could potentially produce two civilisations. And there are a lot of galaxies. 

 

https://www.youtube....h?v=ub747pprmJ8

 

Fermi did have a point; where's ET? lol

[rekokich]

The author’s conclusion is this:
“Intelligence seems to depend on a chain of improbable events. But given the vast number of planets, then ... it’s bound to evolve somewhere.”

 

Habitable planets are extremely common:
https://science.scie...nt/366/6463/356

 

Fermi Paradox is a false dichotomy which violates informal logic:
https://www.cloudyni...i-paradox-r3162

 

On the whole (with isolated exceptions), evolution consistently progresses toward more complex life forms because increased abilities confer better survivability.

 

History and science show that excessive self-regard never served humanity well in the past.

[Old Man]

Does this mean the "facts" that Georgie Boy presents on the television series "Ancient Aliens" is just not true?   .

  No small wonder I have only ever seen one unidentifiable flying object in my lifetime, back in 1958. Now my hopes of that have been dashed. 

 

          Mike

[Shorty Barlow]

https://www.cloudyni...i-paradox-r3162

 

op cit:

 

With relatively high confidence, we know the following:

 

-Probability of complex organisms increases with the passage of time.

-Evolutionary pressures favor the emergence of the brain and intelligence.

 

 

I'm not confident that the probability of complexity increases with time. Complexity seems to be more of a by product of biosurvival. 

 

Does evolution really favour intelligence? How many intelligent organisms are on this planet compared to unintelligent organisms? It could be stated that insects are more successful than us in sheer numbers, and they are far older,  but they mainly possess only an instinctive or rudimentary intelligence, or so it seems to me. And I include social insects (ants, termites, wasps, bees) in that category.

[Shorty Barlow]

Does this mean the "facts" that Georgie Boy presents on the television series "Ancient Aliens" is just not true?   .

  No small wonder I have only ever seen one unidentifiable flying object in my lifetime, back in 1958. Now my hopes of that have been dashed. 

 

          Mike

Yeah, well, his best mate is Erich von Däniken. What do you expect? lol

[TOMDEY]

Interesting --- certainly would seem that humanoids very similar to us would be extraordinarily unlikely... but intelligence itself could be (relatively) common --- unless that particular trait is not fit for survival ---which indication we seem to have right here aka an inherently suicidal species --- propensity for wars etc.

 

But, but... even ants routinely go to war!    The jury is still out, no doubt cannibalizing a neighboring tribe --- and there is no justice in the animal kingdom!    Tom

[Shorty Barlow]

Interesting --- certainly would seem that humanoids very similar to us would be extraordinarily unlikely... but intelligence itself could be (relatively) common --- unless that particular trait is not fit for survival ---which indication we seem to have right here aka an inherently suicidal species --- propensity for wars etc.

 

But, but... even ants routinely go to war!    The jury is still out, no doubt cannibalizing a neighboring tribe --- and there is no justice in the animal kingdom!    Tom

I've heard there are some pacifist hippy ants somewhere. Unless they've become extinct.

[Ron359]

"Our evolutionary history shows that many key adaptations – not just intelligence, but complex animals, complex cells, photosynthesis, and life itself – were unique, one-off events, and therefore highly improbable."

 

I'm not gonna waste time reading the whole article.  Because at least from that statement it is very evident that the author doesn't understand the Theory of or process of Evolution and therefore his conclusion is baseless.  Evolution itself is based on non-unique, non-one off events.   Evolution itself is a process of biologic change to meet new changing conditions.  Evolution from simple to complex life forms is caused by many events each building on the other.  If each were unique and "one-off",  then only extinction could occur and all life would end or never progress beyond one-cell.   

 

His second statement harkens back to 'pre-scientific thought' based on catastrophism, Biblical stories and the Earth is unique and 'common sense' that Earth is the center of the Universe.   

 

To  make an analogy of evolution to the progress of scientific knowledge.  If Issac Newton were a unique, one-off event or person, then he could not have made the discoveries he did and said, "I stand on the shoulders of giants."   And he also stands on the 'shoulders' of one-cell amoeba and other single celled organisms, sponges, fish, amphibians, reptiles, early mammals, Cro Magnon etc., etc. etc.

 

The central tenant of all evolutionary geology and biology is:  "The present is the key to the past."   

Edited by Ron359, 18 October 2019 - 10:40 PM.

[llanitedave]

Evolution never told ME that!

 

Intelligence evolved at least twice on Earth, with primates and with cetaceans.  Interestingly, both trends occurred independently, but over roughly the same time frame.  A number of other evolutionary lines are at least "semi-intelligent":  Canines, equids, corvids, some parrots, elephants, and maybe even octopi.

 

So while any given random "earthlike" planet that develops life would probably not evolve it along the same lines as terrestrial life, complexity and intelligence are far from out of the question.  The timelines may be different and the forms it takes may be different, but I see no real reason for it to be particularly rare.

 

(Although no doubt it would be less common than simple, bacteria-equivalent life)

[llanitedave]

https://www.cloudyni...i-paradox-r3162

 

op cit:

 

With relatively high confidence, we know the following:

 

-Probability of complex organisms increases with the passage of time.

-Evolutionary pressures favor the emergence of the brain and intelligence.

 

 

I'm not confident that the probability of complexity increases with time. Complexity seems to be more of a by product of biosurvival. 

 

Does evolution really favour intelligence? How many intelligent organisms are on this planet compared to unintelligent organisms? It could be stated that insects are more successful than us in sheer numbers, and they are far older,  but they mainly possess only an instinctive or rudimentary intelligence, or so it seems to me. And I include social insects (ants, termites, wasps, bees) in that category.

It's likely that the odds of any single evolutionary lineage developing intelligence are quite low, but the more lineages that exist, the more complex the ecosystem, and the greater the biodiversity, the greater the odds would be that at least some of those diverse evolutionary directions would include the acquisition of intelligence.

 

Many worlds may never evolve beyond the level of prokaryotes, but... they might.

[Joe1950]

I've heard there are some pacifist hippy ants somewhere. Unless they've become extinct.

Bet they smoke grass!

 

 

It seems the ‘odds against’ approach are fully based (biased) on what happened here on earth. Sure it’s possible, but one cannot eliminate an almost countless number of other ‘alien’ evolutionary scenarios that would likely follow a different path than here. 

 

Why would alien life and intelligence have to hurdle the same barriers that got life to where it is. Even here on earth, alternate biologies could have resulted in intelligent life... and still can. 

 

Evolution is is a process that seeks out the best routes to success, not a process confined to stumbling onto one lucky break after another. It’s more like lightning which sends out many feeler paths and then, at the last micro-second chooses the most promising route.

 

Anyway, show me any object, process, condition etc. in the universe that is singularity unique. 

 

On a distant planet....

B: Hey Ekk, yo Ekk!

E: What’s up Bleem?

B: Check this out. I just picked it up on the sub-space link from Earth.

E: What, more on the dude with the big hair?

B: No, no. This article says it could be highly probable that THEY are the only intelligence in the universe!

E: WHAT? Not back to that again. Didn’t they learn anything from that Ptolemy dude?

B: Guess not Ekk. Strange creatures, man.

E: You got that right pal. And they have the nerve to wonder why none of us communicate with them. Hello!

Edited by Joe1950, 18 October 2019 - 11:41 PM.

[TOMDEY]

I've heard there are some pacifist hippy ants somewhere. Unless they've become extinct.

Rumor has it they succumbed to ~Reefer Madness~ Here's a picture of them harvesting the weed. >>>

Attached Thumbnails

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[Shorty Barlow]

Bet they smoke grass!

 

 

It seems the ‘odds against’ approach are fully based (biased) on what happened here on earth. Sure it’s possible, but one cannot eliminate an almost countless number of other ‘alien’ evolutionary scenarios that would likely follow a different path than here. 

 

Why would alien life and intelligence have to hurdle the same barriers that got life to where it is. Even here on earth, alternate biologies could have resulted in intelligent life... and still can. 

 

Evolution is is a process that seeks out the best routes to success, not a process confined to stumbling onto one lucky break after another. It’s more like lightning which sends out many feeler paths and then, at the last micro-second chooses the most promising route.

 

Anyway, show me any object, process, condition etc. in the universe that is singularity unique. 

 

On a distant planet....

B: Hey Ekk, yo Ekk!

E: What’s up Bleem?

B: Check this out. I just picked it up on the sub-space link from Earth.

E: What, more on the dude with the big hair?

B: No, no. This article says it could be highly probable that THEY are the only intelligence in the universe!

E: WHAT? Not back to that again. Didn’t they learn anything from that Ptolemy dude?

B: Guess not Ekk. Strange creatures, man.

E: You got that right pal. And they have the nerve to wonder why none of us communicate with them. Hello!

I bet they smoke a lot of grass lol. I'm no expert but I thought evolution was a process of stumbling onto lucky breaks. 

[Shorty Barlow]

Rumor has it they succumbed to ~Reefer Madness~ Here's a picture of them harvesting the weed. >>>

Definitely some spaced out ants.

[Joe1950]

I bet they smoke a lot of grass lol. I'm no expert but I thought evolution was a process of stumbling onto lucky breaks. 

True. I worded my opinion unclearly. 

 

The way I read the article is that the authors require alien life to stumble onto the same lucky breaks we did. That would be highly unlikely and like winning a multitude of lotteries.

 

I’m saying there may be many paths available that aren’t a carbon (no pun intended) copy of what happened here. Alien intelligence may have stumbled onto an entirely different set of lucky breaks to get where they are. That would open up more possibilities. 

 

Just my humble opinion. 

 

ADDED:

​It’s likely the most important question in human history. Aside from ‘Who are Rey’s parents?” Right now, we have no information that would tip the scales either way. A lot depends on finding any sign of life, anywhere else in the solar system or galaxy.

 

At this point, as far as I am concerned, it would be a much, much bigger discovery if we somehow find we are alone in the universe or even the galaxy. And very disconcerting. Thinking that a series of events under just the right conditions with staggering odds against it is hard to comprehend. And that it happened with such a staggering number of stars and planets in the observable universe.

 

Nature doesn’t seem to work that way with anything else. Nature seems to favor the rule rather than the exception. Why would intelligent life be the exception? 

 

I hope I’m around to witness some kind of evidence, either way. Right now it’s conjecture.

Edited by Joe1950, 19 October 2019 - 02:48 AM.

[rekokich]

-Probability of complex organisms increases with the passage of time.
The first known forms of life were unicellular prokaryotic archaea around deep ocean hydrothermal vents. It took about 4 billion years of gradually increasing complexity before multicellular and highly intelligent bipeds could begin reaching for the stars. The probability of humans “appearing” 4 billion years ago was essentially zero. One million years ago, it was already “pretty good” because the complexity of our organism could not arise without all the intervening layers of complexity which evolved during the passage of time.

 

-Evolutionary pressures favor the emergence of the brain and intelligence

In its fundamental form, applicable to humans, animals, neural network circuits, and AI software, intelligence is the ability to store memories and use them to solve problems. Since basic survival is the ultimate problem for all living things, evolutionary pressures favor those who possess the ability to retain and rationally process previous experiences.  This does not mean that intelligent individuals are incapable of irrational interpretations, or that less intelligent species can not have much higher birth rates and population densities than humans.

[Shorty Barlow]

True. I worded my opinion unclearly. 

 

The way I read the article is that the authors require alien life to stumble onto the same lucky breaks we did. That would be highly unlikely and like winning a multitude of lotteries.

 

I’m saying there may be many paths available that aren’t a carbon (no pun intended) copy of what happened here. Alien intelligence may have stumbled onto an entirely different set of lucky breaks to get where they are. That would open up more possibilities. 

 

Just my humble opinion. 

 

ADDED:

​It’s likely the most important question in human history. Aside from ‘Who are Rey’s parents?” Right now, we have no information that would tip the scales either way. A lot depends on finding any sign of life, anywhere else in the solar system or galaxy.

 

At this point, as far as I am concerned, it would be a much, much bigger discovery if we somehow find we are alone in the universe or even the galaxy. And very disconcerting. Thinking that a series of events under just the right conditions with staggering odds against it is hard to comprehend. And that it happened with such a staggering number of stars and planets in the observable universe.

 

Nature doesn’t seem to work that way with anything else. Nature seems to favor the rule rather than the exception. Why would intelligent life be the exception? 

 

I hope I’m around to witness some kind of evidence, either way. Right now it’s conjecture.

That's just it, we have too little information. I can understand evolution is based on random mutation, anything else tends to either end up as teleology or it gets a bit Arthur Koestler. Not that I'd rule out alternative models of evolution entirely, but a little evidence for them would help. Otherwise, as you say, it's also in the realms of conjecture.

 

As for ET, I'm tending to swing towards the 'life is rare' scenario, rather than a universe teeming with little green men. I doubt we could ever prove there is not, has never been, and will never be, any other life outside of our own biosphere.

 

If there is advanced life though, lets just hope they're friendly and don't have blasters!

Edited by Shorty Barlow, 19 October 2019 - 07:01 AM.

[Shorty Barlow]

-Probability of complex organisms increases with the passage of time.
The first known forms of life were unicellular prokaryotic archaea around deep ocean hydrothermal vents. It took about 4 billion years of gradually increasing complexity before multicellular and highly intelligent bipeds could begin reaching for the stars. The probability of humans “appearing” 4 billion years ago was essentially zero. One million years ago, it was already “pretty good” because the complexity of our organism could not arise without all the intervening layers of complexity which evolved during the passage of time.

 

-Evolutionary pressures favor the emergence of the brain and intelligence

In its fundamental form, applicable to humans, animals, neural network circuits, and AI software, intelligence is the ability to store memories and use them to solve problems. Since basic survival is the ultimate problem for all living things, evolutionary pressures favor those who possess the ability to retain and rationally process previous experiences.  This does not mean that intelligent individuals are incapable of irrational interpretations, or that less intelligent species can not have much higher birth rates and population densities than humans.

So where do the stromatolites fit into this lol? I'm wondering about the time scale. In a universe of around 14 billion years old, is 4 billion years of gradually increasing complexity an average?

 

In other words, is complex life developing on Earth precocious or a bit of a slacker?

 

I think it needs a better definition of 'evolutionary pressures' to claim that 'it' favours intelligence. It seems to me that intelligence and social strategies are coping mechanisms that are essentially a by-product of survival.

[Mitrovarr]

I don't really think intelligent life is probably that rare, exactly. A lot of those mutations listed above are 'easier', in an evolutionary sense, than you'd think. Photosynthesis, in particular, seems like a near inevitability in a world in which life forms have access to light, and isn't really that complicated chemically (not in its simplest forms) and shouldn't be that hard to evolve. Likewise, gene transfer should be pretty easy. Life forms can share genes completely by accident. Come up with a mechanism for accelerating that, and there you are, very simple multi-organism reproduction (the other term is censored, hah). Everything else is just added complexity.

 

The real hurdle seems to be advanced multicellularity and possibly animal forms, but after those evolved, life kind of went crazy. It's hard to imagine a post-cambrian explosion world that doesn't eventually hit intelligent life.

 

As far as why we don't see intelligent life in the universe, I favor other solutions. One is that intelligent life is short-lived (in biological terms) - since it involves fairly large, long lived animals (at least as far as we know, but it seems likely given the general requirements of a brainlike structure), it requires significant planetary stability to survive. Intelligent life that develops technology may be doomed to self-destruct; intelligent life that doesn't might be naturally short-lived, perishing a few tens of millions of years after arising from simple natural causes. There is plenty of time for most worlds to gain, and eventually lose, intelligent life.

 

The other possibility is that long-distance space travel is simply impossible in any significant form. Maybe there really is nothing better than rockets, and inherent limitations in the lifespans of equipment and computers mean that things like generation ships and immortal sentient AIs traveling the stars either don't actually work in practice or are at least rare enough we don't encounter them.

Edited by Mitrovarr, 19 October 2019 - 11:22 AM.

[rekokich]

So where do the stromatolites fit into this lol? I'm wondering about the time scale. In a universe of around 14 billion years old, is 4 billion years of gradually increasing complexity an average?

 

In other words, is complex life developing on Earth precocious or a bit of a slacker?

 

I think it needs a better definition of 'evolutionary pressures' to claim that 'it' favours intelligence. It seems to me that intelligence and social strategies are coping mechanisms that are essentially a by-product of survival.

Stromatolites were formed by photosynthetic cyanobacteria which first appeared between 2.3 and 2.6 billion years ago. Apparently it took about 1.5 billion years of increasing complexity before the appearance of photosynthesis.

 

Partially knowing only Earth's example of evolution, there is no way to define the average time frame for the appearance of a highly intelligent species on exoplanets. Anywhere between several billion years and never is a reasonable first estimate.

 

Yes, ability to survivel and capacity to propagate are the fundamental evolutionary pressures.

[llanitedave]

That's just it, we have too little information. I can understand evolution is based on random mutation, anything else tends to either end up as teleology or it gets a bit Arthur Koestler. Not that I'd rule out alternative models of evolution entirely, but a little evidence for them would help. Otherwise, as you say, it's also in the realms of conjecture.

 

As for ET, I'm tending to swing towards the 'life is rare' scenario, rather than a universe teeming with little green men. I doubt we could ever prove there is not, has never been, and will never be, any other life outside of our own biosphere.

 

If there is advanced life though, lets just hope they're friendly and don't have blasters!

The big leap seems to me to be between "life" and "life with advanced technology."  The latter would certainly occur rarely, but the former may indeed be fairly common.  I'm still hoping we may find some signs of it on Mars, or failing that, Europa.  As for advanced, space-travelling life, we wouldn't need to search every planetary system.  If any such civilization has evolved in the last few million years, they're likely to be close by, out in our Oort Cloud.

[llanitedave]

I don't really think intelligent life is probably that rare, exactly. A lot of those mutations listed above are 'easier', in an evolutionary sense, than you'd think. Photosynthesis, in particular, seems like a near inevitability in a world in which life forms have access to light, and isn't really that complicated chemically (not in its simplest forms) and shouldn't be that hard to evolve. Likewise, gene transfer should be pretty easy. Life forms can share genes completely by accident. Come up with a mechanism for accelerating that, and there you are, very simple multi-organism reproduction (the other term is censored, hah). Everything else is just added complexity.

 

The real hurdle seems to be advanced multicellularity and possibly animal forms, but after those evolved, life kind of went crazy. It's hard to imagine a post-cambrian explosion world that doesn't eventually hit intelligent life.

 

As far as why we don't see intelligent life in the universe, I favor other solutions. One is that intelligent life is short-lived (in biological terms) - since it involves fairly large, long lived animals (at least as far as we know, but it seems likely given the general requirements of a brainlike structure), it requires significant planetary stability to survive. Intelligent life that develops technology may be doomed to self-destruct; intelligent life that doesn't might be naturally short-lived, perishing a few tens of millions of years after arising from simple natural causes. There is plenty of time for most worlds to gain, and eventually lose, intelligent life.

 

The other possibility is that long-distance space travel is simply impossible in any significant form. Maybe there really is nothing better than rockets, and inherent limitations in the lifespans of equipment and computers mean that things like generation ships and immortal sentient AIs traveling the stars either don't actually work in practice or are at least rare enough we don't encounter them.

Geology and the abundance of water may be the sticking point.  While the Sun is a rather average star, and there may be a huge number of planets of comparable size, composition, and orbital parameters to Earth, one area where Earth may be special is in the amount of water on it's surface.  There's enough water to soak most of the landscape, and to fill large oceans that can enable plate tectonics and maintain a vigorous water cycle, but there's not so much that the continents are completely inundated.  It seems like there's a fine line between a world that's almost exclusively oceanic and one that's almost exclusively desert.  Life, even intelligent life, might be abundant on the ocean world,  but there would be no way to discover fire, and no opportunity for the "breakout" that leads to advanced technology.  On the desert world, there may be no life at all, or the harsh conditions may prevent it from evolving real complexity.

 

I think this requirement for a fine water balance may in part explain the hypothetical rarity of extra-terrestrial technology.

[sg6]

-Probability of complex organisms increases with the passage of time.
The first known forms of life were unicellular prokaryotic archaea around deep ocean hydrothermal vents. It took about 4 billion years of gradually increasing complexity before multicellular and highly intelligent bipeds could begin reaching for the stars. The probability of humans “appearing” 4 billion years ago was essentially zero. One million years ago, it was already “pretty good” because the complexity of our organism could not arise without all the intervening layers of complexity which evolved during the passage of time.

 

-Evolutionary pressures favor the emergence of the brain and intelligence

In its fundamental form, applicable to humans, animals, neural network circuits, and AI software, intelligence is the ability to store memories and use them to solve problems. Since basic survival is the ultimate problem for all living things, evolutionary pressures favor those who possess the ability to retain and rationally process previous experiences.  This does not mean that intelligent individuals are incapable of irrational interpretations, or that less intelligent species can not have much higher birth rates and population densities than humans.

Unsure of the Intelligence emergence since as best we know the dinosaurs never developed much and they were around for several million years. Certainly a lot more then we have been.

 

We may be a much rarer being then expected. Our solar system seems "unusual" when you look at the others discovered. So far nothing even close to ours. We have a somewhat big moon that has tidal effects of significance. That could likely have infuenced life and development.

 

Simply counting stars and saying there are lots of them so must be lots of aliens doesn't necessarily add up. Have said that if there are 12 factors and each is a simple 1 in 10 probability we need 10¹² stars and the Milky Way is estimated at 10¹¹ stars. So need another 10 Milky Ways.

 

But intelligence is not it seems a requirement for life and and probably not a certainty as an end point.

[Shorty Barlow]

Stromatolites were formed by photosynthetic cyanobacteria which first appeared between 2.3 and 2.6 billion years ago. Apparently it took about 1.5 billion years of increasing complexity before the appearance of photosynthesis.

 

Partially knowing only Earth's example of evolution, there is no way to define the average time frame for the appearance of a highly intelligent species on exoplanets. Anywhere between several billion years and never is a reasonable first estimate.

 

Yes, ability to survivel and capacity to propagate are the fundamental evolutionary pressures.

Several billion years and never is possibly reasonable. Still conjecture based on insufficient evidence, unfortunately.