That smart guy, Carl Zimmer, has written an article on those smart molluscs, the octopus. I like that his conclusion is that we can't really judge their intelligence, because it is different than our own.
That's the same answer I give to questions about the existence of intelligent life in the universe. I suspect that it's there (but rarer than most astronomers seem to think — intelligence is an extremely uncommon adaptive strategy here on Earth, as is probably likewise elsewhere), but that it will be radically different in intent and action than our own, as different as we are from a squid, or a dolphin, or an elephant, to name a few forms that have evolved large brains. Often, the question of alien intelligence is more like, "Are there people like us out there?", and I think the answer to that one is clearly no, almost certainly not. There are too many alternative pathways.
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H.G. Wells put the probability at a million to one. This was then totally buggered in the musical.
Why have you left the white mice out of the list of intelligent inhabitants of this planet? They won't be happy.
Since there are so many cases of convergent evolution, some evolutionists think there might actually be a decent chance an intelligent biped could evolve again if evolution was re-set from the beginning. They wouldn't be homo sapiens, of course, but something like us might be possible. I wouldn't be so quick to dismiss the possibility. It might be unlikely, but not necessarily near-zero.
I certainly agree that the likelihood of finding "people like us" is remote. And I further agree that abstract intelligence of the sort found in homo sapiens is unlikely to appear even in rich biospheres. However, to my mind, the overwhelming argument against the likelihood of 'people like us' is the Fermi Paradox: since we're not already knee-deep in little green men, there must not be any. The basic idea is that the universe is so old and so big, that, if a species capable of interstellar travel had ever evolved in our galaxy, they would have done so thousands or millions of years ago. It would have taken them only hundreds to thousands of years to populate the galaxy the way that kudzu populates a forest, or pigeons populate a city, or Europeans populate a continent. So, we should have played the role of Indians to the interstellar Pilgrims -- but we're still here! Therefore, there must not by any Pilgrims!
Interesting piece. Makes you think more about how human intelligence itself is really a number of different "intelligences," valued differently depending on the environment and cultural context.
Yes, but these exist because of environmental constraints. What constraints could there be on the shape of sapient life?
Actually, when you think about it, tool use is more common than we typically think on Earth. From elaborate nest building in birds to termite-fishing and the use of sticks and bones among primates in displays/attacks, you see tool use expressed throughout the birds and mammals, as you also see communication. The distinguishing characteristic of human tool use and communication is their creativity and the level of conceptualization involved. Its a difference in degree.
Obviously, its a rare thing for all the disparate factors that drove human evolution to be present and active on a single family of species as it was on our ancestors, but giving the numbers involved, the rigorous competition that all life is constantly involved in, and the great benefit that environment-manipulating tool use grants, ruling out the possibility of it developing among other havens of life, even if it comes out of a different developmental history than our own, isn't something I'd be willing to rule out.
Stephen Colbert's segment on the jar-opening video:
http://cephalopodcenterfold.blogspot.com/2007/06/steven-colbert-officia…
Facinating article. Octopi never cease to amaze me. Then again, neither does the rest of biology. I'm reading Microcosm - great stuff. It's reaferming my decision to go back to school next year for biology.
What is intelligence? Comuter scientist haven't come up with a good definition either. Everytime we settle on one, someone builds a computer/program to meet it, and we lift the bar (i.e. beating a human at chess).
Most of our conceptions have been shaped in a human-centric theistic environment. As I learn more about biology, philosophy and metaphysical materialism, I am forced to rethink a great deal of concepts like what it means to be intelligent, conscious, or good.
Its a shame, but if you think about
it, there was thousands m.a for sapience
to arise, but as far as we know we are the
only ones until now with this ability.
I always thought than this little brain
of us, its unpractical at last. Without
the culture phenomena ill be dead in a night
in a hostile enviroment.
that it will be radically different in intent and action than our own, as different as we are from a squid, or a dolphin, or an elephant,
Probably far more different than that. Squid, dolphins, elephants, and people are all animals, with a common DNA and protein structure. Any aliens out there would almost certainly have different genteic information storage and phenotypic effector systems, as well as radically different brains (or equivalent). Elephants and dolphins are also mammals, so really very, very similar to humans.
Intelligent life is probably out there. But intelligence alone isn't enough. Octopi and such will never develop any technology, because that's difficult to do in an aquatic environment. Birds are intelligent too, but they're limited to using their beaks and such. They won't be building any radio transmitters. Developing a technology is one of the factors in the Green Bank formula, and we're probably quite rare for having done that. Actually, for most of our existence we didn't have technology beyond what's needed to build the Pyramids -- and even that could be regarded as a fluke. We may have the galaxy all to ourselves.
I personally think a more interesting way of framing the question is, "Are there any other beings out there that have produced science and technology?"
I never bought off on that. I think the nature of the universe makes it extremely unlikely that such a possibility is even remotely likely.
First we have the dearth of habitable planets. Second we have the hazards of space. Third we have these massive travel times that grandchildren of the first explorers would be adults when they reached Alpha Centauri with the most sophisticated of the generation ships proposed.
Then, assuming AC has habitable planets with edible life, and no dangerous diseases that'd kill them right off, it would take many, many generations to build a population large enough to support an industrial base to launch the next ship. Even if they wanted to launch another ship.
If your answer is probably "no," how do you square that with evolutionary convergence? I happen to agree that intelligent life in the universe even on planets with life is probably very rare, if we mean intelligences that make sense to ours. By that measure, currently there's one form of "intelligence" on earth out of 5 million species.
That said, it also seems that convergence might play a role - if intelligence exists out there, it may remind us a lot of human intelligence or octopus intelligence or bird intelligence.
"From elaborate nest building in birds to termite-fishing and the use of sticks and bones among primates in displays/attacks, you see tool use expressed throughout the birds and mammals, as you also see communication."
A few years ago I managed to get a short video of some chimps at the zoo using sticks to snag a few precious nuts. It's one thing to hear about animals using tools, it's quite another to have it happening in such a mundane environment, right before one's eyes.
One thing that always struck me about the possible diversity of intelligent life is the variety of additional senses out there. From a bat's echolocation to shark's ampullae of Lorenzini, a variety of animals experience the world in such different ways it is hard to imagine that they would have an intellect structured remotely similar to our own.
I'm sure few people here keep up with such things or have time for silly stuff like this, but in a recently released game called Metal Gear Solid, the main character has a suit made of something called "Octo-Camo" that takes on the colors and patterns of whatever he is surrounded by. Just thought some people here might find that neat.
Here's a video of it in action!
http://au.youtube.com/watch?v=JRIUbOwnDEg
This reminds me of the problems with detecting life at all on elsewhere in space. How do we know what to look for?
The only thing I can think of, just like the evolution of intelligent life, is there there is only a finite number of solutions/strategies to making something. Yes, there will always be really strange things to find out there (Archaea being a prime example), but there are only a few ways to make life work.
I'm reminded of the words of Monty Python's "Galaxy Song", from the movie "The Meaning of Life":
Intelligence is an uncommon strategy, but could life evolve to be intelligent enough to use technology?
If so then they must be considered a threat. As any civilization with the ability to use technology will inevitably develop to a point that relativistic transport is developed. Something with the mass of the space shuttle moving at relativistic velocity has enough energy to kill all life on earth. Because they think we might attack them, they preemptively strike us.
It seems to me kind of a pointless debate triggered by all the science fiction people watch. It's such an unimaginable scale and every new discovery about life, physics, and astronomy alters the probabilities. You have an unimaginable number of galaxies with an unimaginable number of stars and we just don't know the distribution of worlds that could support life.
Even if you take the drake equation, for instance...all we have are guesses, approximations and conjecture to the inputs of it, but we all know GIGO.
Going past that you'd then have to determine the probability that a civilization would develop in a way that would be comprehensible to us (not like dolphins or whatever)...does anyone have the slightest idea how to accomplish that?
The thing I find really interesting about cephalopod cognition is that it occurs in a nonsocial species. The abilities of the various types of apes and monkeys are impressive(though with some odd gaps); but there is something fascinating about getting to look at an apparently intelligent organism whose environment and adaptations are vastly unlike ours.
it seems to me that intelligence evolves out of the need for problem solving abilities--many brains can work out problems that do not arise naturally in their environments. intelligence has a certain flexibility, we appear to have more problem solving ability (in the cognitive sense) than most animals, i cannot really think of a reason to assume that this level of cognition cannot evolve in alien life. even if the circumstances that make intelligence adaptive on other planets are radically different from our own (although why should that be so? it'll probably still come down to resource gathering) as long as there is a certain amount of surplus computing power, abstract intelligence similar to our own is possible. At least i hope so, because the thought is really cool
Other life in the universe that does science? Probably. Converging in time and disatance with us to the point we can know about it. Almost certainly not.
Chris #3
re aliens and the Fermi paradox, I found this a fascinating discussion:
http://www.amazon.com/Universe-Aliens-Everybody-Solutions-Extraterrestr…
He marshals the arguments very systematically, but doesn't come down strongly in any direction. That gives you a game that pretty much anyone can play.
Webb's "conclusions" were pretty much like PZ's, although very tentative: there may well be life out there, but most of it won't have progressed much beyond the microbial state.
The more I read about the intricacies of the eukaryotic cell, the more it seems to be that its development was almost as big a step as biogenesis in the first place.
Supposing that there could be tree-like organisms producing fruit-like food on some alien, the evolution of an "intelligence" like our own ought not to be thought to be too unlikely.
Anyway, I don't actually think octopus intellignece is altogether unlike our own. In fact, we call it intelligence because it has aspects akin to our own capabilities, including leaps to rational solutions for, say, getting food out of cracks, crevices, and enclosed containers.
Of course it's hard to compare octopus and human intelligence, but it's not that easy comparing human and human intelligence.
What makes comparing human and cephalopod intelligence harder to compare than human and human intelligence is not so much what we call "intelligence", as it is what interface their intelligence has with their evolutionary possibilities. They want different things than we do.
But yes, there are basic similarities to anything that we can call intelligence. An octopus "reasons", or in any case, it utilizes what we call "reason". They can articulate knowledge into rational steps to doing certain things, just as primates do--again, that is why we call them intelligent. To bring up a familiar refrain, what we see in evolution is without the planning, forethought, and rationality that humans and cephalopods utilize, which is why we are pretty sure that nothing we'd call "intelligence" has been involved in evolution (save some intelligence in mate selection, and our selective breeding of other species).
Compared with evolutionary results, octopus intelligence is "like ours". Compared with chimp thinking, octopus intelligence is "unlike ours". I believe that there is intelligence "like ours" in the sense that octopus intelligence is like our own, yet I rather suspect that similar evolution has probably produced intelligence much closer to our own than even octopus intelligence is, out there on some planet.
Glen Davidson
http://tinyurl.com/2kxyc7
I think that life is far rarer than most science enthusiasts assume. I know the numbers are big and there most certainly are many planets with water and the proper temperatures in this enormous universe. But the actual conditions that are required for replication to begin is in my guess very, very rare. However, once replication does begin convergence seems highly probable. Heads with sight, sound and smell detectors are going to be vital in any environment. Legs for locomotion and arms with hands are essential for environment manipulation. We're so close in abstract terms to all the vertebrate mammals. Nearly identical when you use relativity as a judgment.
I also believe in an infinitely cycling universe because of the conservation of energy. Therefor, I think that life emerging from non life is inevitable when limited time isn't a consideration. So even though I'm an atheist and don't give any credence to personal reincarnation, I believe that there are indeed "people like us" out there, a "divine" natural design. The real question is when.
Should have been--
I wanted to add, too, that not only to cephalopods want different things than we do, manipulating tentacles is significantly differently than manipulating arms and legs. Making comparison difficult for that reason, as well.
Glen D
http://tinyurl.com/2kxyc7
Why would a head be vital to the gas giant airbags of zebulon-B, whose senses operate at radio wavelengths and whose intellect is dispersed among the swarm? Or to the megaclams of Gwflhrx, whose perimeter is studded with a thousand eyes and whose nerve ganglia are safely protected deep within their mighty shells?
Sometimes not all *that* different. Dolphins *do* have jobs.
Hey, they jump through a hoop and get a fish. That describes 99% of the jobs humans have.
but could life evolve to be intelligent enough to use technology?
Data point: My dad is still trying to master the television remote control.
""Are there people like us out there?", and I think the answer to that one is clearly no, almost certainly not."
So how do you explain those aliens living amongst us, who look almost like us.
The ones who stole my tin foil hat!
Sorry PZ, but that's way too broad to actually mean anything substantial. What are you talking about when you say "people"? Bipedal and two-eyed, with penises and vaginas? Nobody subscribes to that notion of extraterrestrial life.
On the other hand, some traits of human life which are special on Earth (e.g. language) might conceivably have evolved many times in the observable Universe. Maybe they're what Dan Dennett calls "Good Tricks", which are prone to being converged upon independently.
If the MWI-interpretation of Quantum Mechanics is correct, there might be countless numbers of planets with human-like creatures!
But of course it might still be correct, that intelligence is unlikely to appear, even on planets with complex life forms.
If this is the case, any kind of contact with other civilizations could be impossible.
Even within the swarm there are individuals and the head is a most efficient way to give the body the ability to navigate. I'll have to give the megaclams of Gwfhrx more thought but I don't know how far they would get manipulating their environment. Environment manipulation, I think, is a fair way to judge intelligence. Too much manipulation by the highly intelligent might be a good sign of idiocity.
If the MWI-interpretation of Quantum Mechanics is correct, there might be countless numbers of planets with human-like creatures!
Yes, and we don't even need the MWI; other parallel universe models will also do the job. However, this isn't very interesting, as we can't ever actually enter and communicate with the denizens of any of these universes.
First we have the dearth of habitable planets. Second we have the hazards of space. Third we have these massive travel times that grandchildren of the first explorers would be adults when they reached Alpha Centauri with the most sophisticated of the generation ships proposed.
All those points assume an evolved intelligence would send members of its own species rather than artificial life, in the form of von Neumann probes (machines which can build copies of themselves out of planetary/asteroidal material). I'd hazard that the necessary technology is decades away, if we don't manage to screw things up first (which is only too likely).
Nobody subscribes to that notion of extraterrestrial life.
I do.
If that's the case, then how do you morally justify eating them - or other animals?
Scientists seem to be continually upwardly revising their notions of what animals think and feel.
And how does that gauge of intelligence correlate with this one, "Are there any other beings out there who seem to be unable to refrain from relentlessly bent on destroying on their ecosystem?"
Intelligence - a slippery concept all around.
I do.
Only a lunatic would insist that extraterrestrial intelligence has to be two-eyed, bipedal, etc.
I didn't insist it had to be. I said that I think their is a high probability. Less is more most times. Two eyes are all that's required for stereoscopic vision. And I would be pleasantly surprised to discover the evolutionary path of a one legged land animal. Hoppidy hop hop.
The question: "Are there people like us out there?" to me is more "is there intelligence like us out there?" I have few ways to answer that question beyond very rough probabilities and time. Does out there mean right now, in the past, or in the future?
If we think in terms of a broader out there, it seems reasonable that intelligence like ours is emergent and (will, does or did) exist out there.
What seems much less likely is that we will find a means to interact with like intelligence out there - for one thing that restricts the out there intelligent beings emergence to co-incident time with us - beyond the problem of finding a needle in the haystack so to speak.
Oh, so many possibilities! I rather hope that the answer to the question "Are there people like us out there?" is "no". Here we are on the verge of space exploration and all our money is going into warring with each other.
It's seems probable that we live in a predatory universe, but honestly, I hope there aren't many other intelligent species out there "like us" or all that smartness will end up blowing up the damn galaxy in the rush to enslave and dominate.
My guess is that the Galactic Federation has quarantined us because the other worlds have no desire to be subjected to french fries and Jesus.
There is something fascinating, though, about the fact that in our little corner of a big, impersonal universe, we have the capacity to imagine other kinds of intelligence. Weird.
OctoberMermaid,
That's the reason we don't see other intelligent life in the universe. Once they get to a certain point in technology, they spend all their time in a virtual world!
Perhaps the ultimate demise of every highly intelligent species isn't war but their united world particle physics research gone horribly wrong.
Luke @ 2
I have to agree. Although I'm no expert, I have heard it more than once that other beings would be totally different. I don't understand that. Sure, there are many pathways, but the physics and chemistry that are required for human (or like and kind) level of development are very fine filters. In my view, it almost forces convergence. Now I'm not saying that primates are the only functions capable of intelligence. Nature's first try on Earth were dinosaurs. That experiment ended prematurely. Furthermore, Earth offers a huge assortment of environments. Just about every extreme imaginable. We're just now able to contemplate similar environs on other worlds - mostly moons around the Jovians. And yet with all that diversity we only find creatures like us to support intelligence. Bipedalism is not random, nor is 5 point symmetry. Sure there are other types of symmetry, but symmetry is still significant and apparently necessary for many things.
I guess I haven't come across a convincing argument as to how or why intelligent life would look so much different than what we already experience. And I don't mean to argue from ignorance. I am open to all information. If anyone can offer information other than just anecdotal assumptions that life must look so different I would appreciate it. I find it fascinating.
"Man is a successful animal, that's all"
Remy de Gourmont
Let me present a REALLY weird line of thinking:
Assume that there exists a species with enough intelligence to create technology. It will then create technology to alter its environment in such a manner as to improve its living conditions (on earth, for example, homo sapiens came up with agriculture as a means of altering its environment to improve its living conditions.) Each improvement in its living conditions will increase the population of that species, which will in turn permit greater specialization of effort. That greater specialization of effort will permit faster development of new technologies that further improve the environment. Therefore, you get a virtuous circle in which the population grows at an accelerating rate, creating technology that expands at an accelerating rate. However, as its environment-altering technologies expand in scope and complexity, the second-order consequences of these environment-altering technologies must increase in complexity even faster than the technology itself changes (because the technologies are getting bigger in scope AND interacting with each other). The rate of change of the second-order is therefore greater than the rate of change of the population. Accordingly, at some point the species will find itself altering its environment at a rate faster than it can adapt to the changes. After only a short period of this situation, the species must find itself in a situation in which it is no longer adapted to its environment -- and we all know what happens to a species whose environment changes in such a way that it is no longer adapted to that environment.
To put it another way, let's think in terms of evolutionary time scales. Do you really think that earth 10 million years from now will still have homo sapiens?
It truly would be ironic if the condom is what brings salvation to humankind.
Do you really think that earth 10 million years from now will still have homo sapiens?
No. With our advances in bio-genetics and such, we will eventually be able to control our own evolution and adopt whatever suit of flesh strikes our fancy. Primate bipedalism will be so blasé.
Chris @ 46
I find Kurzweilai.net interesting. Certainly organic biology is too frail to withstand the test of time. But AI does not require organic structures. IMO Human kind is not the pinnacle of intelligence or creation. I think there are very compelling arguments that show that AI is. Just how it gets integrated into humanity is the question. Perhaps we'll be able to re-grow organs and limbs pretty much at will. Perhaps some of us will prefer more robust non-biological structures as a substitute. It's hard to see up that curve.
Except for the appendix, I think we're perfect. Blazé Bourgeoisie.
Not buying it.
Intelligent tool using is so powerfully adaptive that any species that gains this ability should dominate their planet. There are many fierce and large carnivores that were all around. The survivors are scarce and mostly frightened out of their wits by us.
As to how many technological civilizations there are in the galaxy, we don't know. There are 200 billion to a trillion stars in our galaxy and we have looked at a tiny fraction of these. All we can say is that there are no aliens broadcasting sitcoms within a few dozen light years of us.
As to the Fermi paradox, that is a crucial question. No one knows. It could be that technological tool users routinely see their technological ability to destroy themselves outrun their ability to not do so. Or that deep space flight is too difficult with no quick payoff and no one ever gets around to going anywhere. Just guesses, could be anything.
The corrolary is exciting though. If we ever get our act together, we could colonize the whole huge galaxy and own it all. Or sit at home, watching sitcoms while pretending that the earth is 6,000 years old and using up 300 million years of fossil fuels.
With Kepler, we're soon to have a much better grip on the frequency of habitable-zone terrestrial-size planets in the galaxy. And the galaxy is vast. (Somebody above asked what you would look for to find life. The answer is atmospheric disequiliribrium.)
As for the Fermi question, and the von neumann machine colonization idea, the barrier may simply be the extravagent energy resources necessary to even begin to bootstrap any form of interstellar travel. Presumably ETI passes through a phase of its planetary existence much like the one we now inhabit: technology and population pressure start to overwhelm planetary systems (oceans, atmosphere). And you either come through that okay, or after a few centuries population is drastically reduced, as is the baseline tech level, and the long slow climb to planet-altering technologies begins again. One can imagine a species locked in a cycle like this, with many iterations spanning tens or hundreds of thousands of years each.
For the species that come through environmental degradation okay, the question becomes, what then is the impetus for bootstrapping planetary-scale technology into galactic-scale tech? It's been suggested that it would only take one expansionist civilization in the entire history of the galaxy for us to see them everwhere, and that seems right, so maybe there really hasn't been one. Personally, I think ETI exists (or has existed) but is rare and thinly distributed in space and time. If the lifetime of a technological civilization on average is only several hundred years, there is almost no chance we'll ever make contact with 'someone like us.' And there's a good chance that an outlier, who have solved their planetary-scale problems, would want nothing at all to do with us.
I didn't insist it had to be. I said that I think their is a high probability. Less is more most times. Two eyes are all that's required for stereoscopic vision. And I would be pleasantly surprised to discover the evolutionary path of a one legged land animal. Hoppidy hop hop.
And do you think there's also "high probability" that they would have anything resembling a penis and vagina? There's no reason you should be so confident. As best, it's an interesting guess.
Yes there is a reason I think that a penis and vagina is likely. When a species reproduces sexually the goal is to get a seed into an internal egg. The penis is really nothing more than a stick prob. And the vagina is a glorified hole. I can even intelligently guess at reasons why the the nuts and clitoris are highly probable in completely separate evolutionary chains.
I have no doubts about the validity of evolution. The molecular evidence and witnessed micro evolution and mutation is quite sufficient. There's no god planting junk DNA or burying the fossils to deceive us. But seeing as though radio carbon dating is only functional up to 60K years and the fact that only a tiny fraction of all the life that has existed on earth will be found in a fossil form means that the history of our evolution will always have a certain level of speculation involved. But from what I've read about the subject, a great deal of the "facts" of evolutionary history is already intelligent guessing.
@ #42
"Once they get to a certain point in technology, they spend all their time in a virtual world!"
If I had a cool suit like that, I wouldn't need that virtual world! Oh, the fun that could be had.
very interesting indeed but isn't it almost completely speculation with very little real hard data.
that intelligence is variable with life on earth is a given and our understanding of it is as in most things very egocentric at the least. Intelligence like us given the range in our own species (ie the fundies?) is rather staggering the galaxy song came to my mind also.
If we look for some one like us I would say that we should look for "someone" who is the most destructive species in their environment as the main criteria to characterize "people like us".
we seem to have as one our main abilities the ability and desire to make major and continuous change and unlike animals like beavers our changes do not increase the complexity of the ecosphere but to narrow it starting with farming. that some other animal might have evolved to high intelligence along different lines that we have not considered nor could identify seems likely. it is just recently that we have even begun to consider what intelligence is and how it functions as a survival tool. many of the things we once considered to be ours alone are no longer seen that way.
still we seem to be the absolute messiest one here hands down. We invented the pigsty.
See also Peter Watts' Blindsight, wherein he posits aliens who aren't actually conscious (smart as hell, but not conscious as we know it).
The "Vampires" link there provides some hilarious back-story to the super-autistic vampires that are in the book. The biology is a bit woo-woo but the presentation is chillingly realistic (politically speaking).
That's why God invented lutetium-hafnium dating, potassium-argon dating, rhenium-osmium dating, rubidium-strontium dating, samarium-neodymium dating, uranium-lead dating, uranium-protactinium dating, uranium-thorium dating, paleomagnetic dating, fission track dating, and thermoluminescence, among other techniques.
Many fish and plants use external fertilization (e.g., female salmon lay eggs, then male salmon swim over them secreting sperm). And even in species where that is "the goal", you don't always get penises (the males of some species, such as spiders, insert their sperm via manipulators that are separate from the sperm producing organ). It's also the case that even when eggs may be held internally for development, they are not held internally via a vagina (think of all the animals that brood their young in pouches, or where the males brood the young in their mouths).
And all this presumes that alien life will involve "sexual reproduction", at least in a manner that we know it. (There may be other mechanisms used to promote genetic shuffling, for example -- bacteria don't have sex, yet readily incorporate foreign genetic material.)
Yes there is a reason I think that a penis and vagina is likely. When a species reproduces sexually the goal is to get a seed into an internal egg. The penis is really nothing more than a stick prob. And the vagina is a glorified hole. I can even intelligently guess at reasons why the the nuts and clitoris are highly probable in completely separate evolutionary chains.
Reminds me of a Sherlock Holmes novel. You're indulging in pure speculation and asserting unwarranted confidence in your conclusions.
I could easily contest your notion that a "stick probe" is a Good Trick. Maybe, for instance, genetic information is on Planet X fired over moderate distances. (I accept that there are fairly good reasons for supposing they'd be sexually reproducing.)
Try as you might, you can't prove using this a posteriori method that various physical properties of humans were inevitable. I have no problem with your taking an interesting, informed guess. But it's absurd to say, "Two eyes, two legs, and a penis or vagina are all highly probable features in any intelligent organism."
Many fish and plants use external fertilization (e.g., female salmon lay eggs, then male salmon swim over them secreting sperm).
Yes, exactly. And bear in mind that evolution on Earth has been subject to all sorts of constraints which mightn't be in place on an alien planet. There could be all sorts of novel, effective, non-Earthly ways of transmitting genetic information.
I think some kind of stereoscopic sense organ(s), some organ for manipulating the environment, and some means of communicating with others of its kind, would be highly likely in any intelligent and technologically capable lifeform.
How similar/analogous these things on an alien would be to our human equivalents (eyes, hands, language, etc) is an open question. It's difficult to make meaningful hypotheses when you have a sample set of one.
Primate bipedalism will be so blasé.
No, they will be retro, and hugely popular once a century or so.
I think that people are unnecessarily confining themselves to narrowly terrestrial standards of visualizing living systems. Remember the fundamentals, which have nothing whatsoever to do with water or carbon or any particular temperature or atmosphere. The fundamental driving force for living systems is negentropy. Where you have large amounts of negentropy, you have a better chance of getting living systems. Yes, you also need some physical characteristics that permit complex structures -- but there are lots of these things. Several layers inside a star, for example, have negentropy transport rates that are many orders of magnitude higher than what we have here on earth, and magnetohydrodynamics makes organic chemistry look like pulleys and levers in terms of complexity. So, how about plasma creatures* inside stars? Or how about living systems on the surfaces of planets so close to their parent stars that there's liquid metal?
*Oops, I used the word "creatures" when I meant "living systems". Does that make me a creationist? Horrors!!!
The fundamental driving force for living systems is negentropy. Where you have large amounts of negentropy, you have a better chance of getting living systems.
Negentropy is an effect of living systems. It's one indicator by which we might recognize a living system very different from terrestrial examples, but I think you need to explain more how it's "the driving force," which I take to mean "the cause," of living systems.
I would think that where you already have nonliving systems producing negentropy, living systems would be less likely to arise, not more.
I'd say that while intelligent life may be very different from us, there would likely be some similarities between us and an intelligent organism capable of developing technology:
"Breathing" gases: A liquid environment is not amenable to fire. Fire is necessary for pretty much all of our technology, and it's difficult to imagine a case where technology could arise without it.
The "5 senses": It seems that the ability to develop technology would rely on the ability to perceive the environment. Most of these would seem to be the minimum necessary to do this, though taste/smell would be the most variable, and other means to do this, such as say electromagnetic communication instead of hearing, would seem unlikely.
At least 2 "hands": The ability to manipulate objects would seem to be necessary for developing technology.
Without those, it would seem that developing advanced intelligence on par with humans would not provide an evolutionary advantage. Of course, I am subject to my biases, but I see no reason that natural selection would work differently anywhere else.
If our mind is a construct of memes and if you buy into memetics...why not? Couldnt other species have the ability to imitate like us and have ideas? And the brain is the environment for memes! I think yes!!
Reminds me of a Sherlock Holmes novel. You're indulging in pure speculation and asserting unwarranted confidence in your conclusions.
That sounds to me like what a lot of evolution history is. Without being able to compare the genome of ancient animals aren't we left with a lot of unwarranted confidence in many conclusions?
I obviously don't completely grasp the method of dating fossils. And I did know that there were other radioactive decay methods but I assumed that carbon was the only one that's used to date animals because that's the end of the carbon 14 and 12 equilibrium exchange ratio.
At any rate, I'm kind of shocked at the almost hostile response I've received from speculating that the human form is one of great natural and eternal significance. What if rephrased it so as to say that we follow a significant template? Would that be better;)? You people make me feel like a fundie. A radical Naturalist, that's cool.
I also think aborting post 7 week fetuses is murder and I even have reasons for that. I better put on my blogbulletproof vest.
OctoberMermaid 55#
See "The Nonprevalence of Humanoids", George Gaylord Simpson, Science 144: 769-775. Reprinted as Chapter 13 in "This View of Life."
As I understand it, it took several sequental stellar life cycles to produce the elements necessary for life as we know it. So maybe we are the first technological civilization in the universe. So far as taking over the universe, we cannot do so with physics as we know it. However, we have had fully scientific physics only since Newton. One wonders what a species who has had physics for, say, 10,000 years might be able to do.
maybe we are the first technological civilization in the universe.
One of the things that makes this such a fascinating subject is that this answer would be just as humbling and awe-inspiring as the alternative.
[Pure speculation] sounds to me like what a lot of evolution history is. Without being able to compare the genome of ancient animals aren't we left with a lot of unwarranted confidence in many conclusions?
Much less speculatory than what you're doing, for plenty of reasons. The genetic machinery of life on other planets may very well be entirely different from what we have on Earth. And while it seems a good bet, it's nowhere near certain that intelligent life has to be sexually reproducing.
Your educated guesses are intriguing and were fun to read, but I think calling them "very probable" is definitely going to far.
I obviously don't completely grasp the method of dating fossils. And I did know that there were other radioactive decay methods but I assumed that carbon was the only one that's used to date animals because that's the end of the carbon 14 and 12 equilibrium exchange ratio.
The carbon clock can take us up to about 60,000 back. I think fossils older than that tend to be dated by more geological clocks, e.g. potassium-argon.
Anyway, perhaps I'm missing something, but how is this relevant?
"60,000 years", that's supposed to be.
The number 60,000 sure seems to be cropping up a lot of late.
Much less speculatory than what you're doing, for plenty of reasons.
I'm well aware of that. All of my "evidence" is purely metaphysical. At least evolution has fossils and DNA.
Anyway, perhaps I'm missing something, but how is this relevant?
I know I'm missing something. I don't know how a rock can be dated. The elements that make the rock can, but doesn't that only date when the elements that composed the rock were made?
How we date rocks,
From the USGS:
That's just a short explanation. Follow that link for specifics, with examples.
Thanks
This is basically an Argument From Personal Incredulity. The key word is "our." Aliens, aquatic or otherwise, may well find some other path to achieving the sorts of things we do with our technology.
For example, imagine a race of intellgent, social cephalopods :) who evolve a way to take in, manipulate, and exchange DNA similar to the way bacteria do. Perhaps initially using DNA molecules the way we use pheremones. At some point, their ability to do this becomes highly sophisticated. They develop a "sense organ" that lets them percieve the shapes of these exchenged molecules, and perhaps also evolve the ability to spread them via retroviruses.
In time, they develop a kind of animal husbandry that includes "tasting" the genomes of tamed animal species. Instead of an "Industrial Revolution," they have a "Genetics Revolution," in which they discover how to intentionally manipulate the genomes of other species. So, if they want a vehicle, they genetically engineer a fast-swimming fish to incorporate a carrying pouch with a large enough "window" (derived from eye-lens material) for them to see through, and little appedages inside the pouch the cephalopods can manipulate with their arms as controls.
Someday they could develop "jellyfish blimps" to explore the atmosphere and land surface of their world. I imagine getting into space would be more difficult for them than for us. Even so, I can imagine a huge, high-altitude "jellyfish zeppelin" with a large surface area for solar energy collection that uses bioelectricity for propulsion in a manner similar to the mechanism of a Myrabo disk. If it is able to generate enough energy to overcome air resistancce in the upper atmosphere, it could conceivably accelerate gradually until it reached orbit or escape velocity.
Once in space, it could maneuver around the inner solar system, where solar energy is abundant enough to provide power. If the aliens' mastery of genetics is advanced enough, they might be able to launch diaphenous jellyfish-like 'starwisp' probes or engineered microbes out into the rest of their solar system and beyond.
None of this seems physically impossible to me. I am not a biologist or physicist, so maybe there's some limiting factor I'm unaware of.
On the other hand, we humans with our vaunted fire haven't done so well as space explorers. We sent a few members of our species to the nearest available rock for short visits, then turned the job over to machines. Apart from some magic "antigravity" physics, the economics of space travel will always favor machines over humans. Machines are getting smaller, lighter, and smarter all the time. Astronauts (and the tons of oxygen, water, and food they need to survive) aren't. As long as you've got to throw stuff out of the back of a spaceship to get anywhere, smaller/lighter is better.
My guess is, if we ever see an "alien," it'll be a lot more likely to look like V*ger (or maybe a microscopic machine or genegineered bacterium) than like a "bumpy-headed human."
I know I'm missing something. I don't know how a rock can be dated. The elements that make the rock can, but doesn't that only date when the elements that composed the rock were made?
Well, I'm neither a chemist nor a paleontologist, but I'll give it a go.
Radiocarbon, produced by bombardment of cosmic rays on nitrogen, is oxidized to carbon dioxide and absorbed into plants. When plants die they stop absorbing radiocarbon, and the supply they have then decays. The proportion of radiocarbon to stable carbon in living things can be found by experiment. We also know the time it takes for half the radiocarbon to decay; using some mathematics, we can work out how long it takes for decay into the current proportion of radiocarbon to stable carbon.
That's how the carbon clock works (as I understand it). I would imagine that the other methods operate on vaguely similar principles (with different radioisotopes, of course).
Total number of planets
Number that can support life
Number that do develop life
Number where organisms develop centralized nervous systems
Number where organisms develop means to manipulate their environment
Number that develop civilization
Number that develop high-energy technology.
Number that do not destroy themselves by war or pollution.
Number capable of interstellar flight
Number willing to put forth the effort. I expect this will be a very small number.
Did I leave anything out?
I read an article recently where the author spoke of a "great filter". It could very well be that up to a certain level of development that life is abundant. But after that point, some great filter destroys it. Obviously the great filter, if it exists, is in our future. Also, it doesn't make sense for it to be a cataclysm like GRBs or anything. It is an ultimate test of civilization. Pollution, disease, self-inflicted disaster. If the great filter doesn't exist, why don't we see more evidence of extraterrestrial intelligence? Ah the questions.
So how do you explain those aliens living amongst us, who look almost like us.
Hungarians.
Homo Sapiens Sapiens is already extinct. He just doesn't realize it yet.
In very short order we shall cast aside these fragile, mortal forms and expand our minds a million times beyond what our small, grey, sacks of mush can currently conceive. When we chose to don bodies they will be far more resilient and resource conserving then the wasteful, organic, piles of meat that we currently wear. To "those that we will become" a 20th century man will seem as primitive and foolishly pathetic as a worm seems to him. Their technology will quickly come to the point where the condition of the outside environment becomes almost irrelevant to their survival and any immediate external threat could be easily mitigated. Freed from the need to feed their inefficient organic forms and reproduce uncontrollably, the amount of resources needed to maintain survival will quickly drop below what the Earth is capable of sustaining nearly indefinitely. This won't take thousands of years, but maybe just one or two hundred years from now. There will never be a need or opportunity for a primate to leave the solar system.
After negating the need for increasing resources through technological development and population equilibrium, then what purpose is colonization?
Aside from seeking out excruciating detail, there is little about the universe that can not be determined locally or through non-colonization techniques. To Post-Humanity finding another "intelligent" being would merely be an exciting exercise in discovery but unless they are on an equal technological level what purpose will there be to contact? It would be like humanity trying to make contact with an ant hill. What could be gained except satisfaction of curiosity? Even if you could drop to their level and have conversations what would it achieve?
The answer to "will we find others out there like us", is no. We (homo sapiens) will not be doing the looking. Our progeny may find other "intelligent" life, but the question to them will be nothing more then a curiosity.
The answer to Fermi's paradox is:
1) Given the young age of the Universe, we are the first life form in this galaxy to be taking steps into space.
2) They haven't been here yet because ubiquitous expansion through colonization is unnecessary for a sufficiently advanced civilization's survival and therefore they would not have filled the galaxy even though there has been sufficient time.
3) They have been here and found us too primitive to bother contacting or destroying.
This thread is like a conversation with the alien creators of Star Trek and Steven Hawking. The producers complain that all the aliens look too humanoid demanding more pizza monster types. Steven counters stating that what we really need to do is grow humans outside of the mother so the brain size isn't limited to the birth canal.
Yes, mollusks are surprisingly smart and we may not understand in all ways. Remember that really smart parrot that Dr. Irene Pepperberg showed could learn meanings of words, and even pick up "wood" objects versus "metal", how many, etc?
"...but rarer than most astronomers seem to think -- intelligence is an extremely uncommon adaptive strategy here on Earth, as is probably likewise elsewhere..."
That's interesting. It's true, most astronomers don't think beyond the fact that it happened here and, given enough time, it will happen anywhere life originates. I'm glad we have astrobiology as an emerging field to bring these lines of communication together.
"...but that it will be radically different in intent and action than our own, as different as we are from a squid, or a dolphin..."
So long, and thanks for all the fish.
Interesting discussion; read Sagan and Schlovskii's Intelligent Life in the Universe, the Simpson essay, Drake's Is Anybody Out There?, Damien Broderick's The Spike, a bit of Kurzweil, Greg Egan's Diaspora, and other such stuff (I even read a couple of Frank Tipler's books - they're now shelved next to Roger Penrose's and the Bible - but prefer to see eschatology done explicitly rather than unintentionally as SF, like Egan, or Greg Bear's Eon and Eternity). I kind of agree with A Barely Literate Ape (#83) except I actually like being a squishy carbon-based life form, and I think that kind of thing - and particularly, the currently available diversity of that sort of thing - is worth preserving. The extinction we're presiding over at the moment is heartbreaking enough; the best reason I can think of for breaking out of the Solar system is precisely to transplant Life - As We Know It - to other places where it may have a chance of outlasting our Sol. Including at least some of the primates. Why worry about conservation in the here and now (as many of us do), while abdicating from any concern about the long term future of earthly life?
Interesting, but perhaps not Zimmer at his best. He somehow missed that mollusks are jetting with water.
So, for the experts here, did he also miss that one of the octopuses are mimicking some algae, or is my understanding of the limits of flexibility of the coral calcium skeleton seriously lacking? Does any living coral stream with the water flow like that?
Reposts part of my comment from Jason Rosenhause's review of Miller's new book Only a Theory: Evolution and the Battle for America's Soul, which spawned a discussion over theistic evolution need for a "human equivalent intelligence". (The quote is from Gould.)]
Any resemblance of irony over particular arguments on this thread is unintentional. I also think, re raven, that the fermi paradox is indicative but similar in scope.
To be fair to bayesian models of learning, I have seen some attempts to make more rigorous Markov models, trying to extract real key contingencies from the historical record by various assumptions. They just don't seem very predictive to me, nor do they manage to establish that.
Ooh, this is fun, let me try too!
Let me see, we have three cell domains, but only one went on to adopt organelles by endosymbiosis. So the a priori probability for that is only 30 %. OTOH, we have on average 3 cell domains for every known planet with a biosphere, so the a posteriori likelihood for such complexities is 100 %. :-P
Hmm. Doesn't seem like such a large step to me. How would one measure the size of it?
One could improve on the analysis by looking at the arrival time to a feature. This seems to make abiogenesis quite probable, because first life occurred very shortly after Earth consolidated. (And that could include any number of successful abiogenesis processes in series or parallel.)
OTOH AFAIU endosymbiosis has occurred many times in series and parallel, so it doesn't seem like a problem here.
Wang et al hypothesizes that the different ecological niche specialties of Archaea, Bacteria and Eykaryota was that lead to the domain specification (and later speciations) in the first place. Seems like a more predictive scenario to me.
Their model is nice in other ways too, as it predicts a more dispersed accumulation of traits in relevant domains. The complexities doesn't seem like such a large step then. What riddles me more is how simplified Bacteria has managed to become in their ecological perspective while still eking out a risky existence.
Probably yes and no; yes, entropy is probably important and truly indicative for life and no, it doesn't seem vital.
- One way to see that entropy probably is important is to look at objective anthropic principles such as the causal entropic principle. They nicely predict that our universe is maximizing (non-gravitational) entropy by producing dust, i.e. stars and planets.
[It also explains the coincidence problem in entropic terms, observers are likely to be found at the time entropy production is maximized; which is right now in our universe, at the time dark energy takes over to spread out the galaxies faster.]
This is also consistent with inflation, which AFAIU can be started in low entropy universes and reversely that universes can only be expected to grow to large sizes if they start out low entropic.
So entropy will grow and if so we may have global conditions supportive for life.
- Entropic production would be truly indicative of life because astrobiologists will look for life in atmospheres out of equilibrium, with for example free oxygen and ozone et cetera.
- But AFAIU entropic production isn't vital for life, locally.
Metabolism seems to be near equilibrium affairs, with growth and so evolution as slight disturbances. Of course organisms also employ far-from-equilibrium processes such as the evo-devo diffusion-and-contra-diffusion time and space regulation for body parts PZ likes to describe.
Whatever functions; isn't that what selection goes for?
Under these conditions it seems to me life could probably occur and subsist in low entropy producing environments. It may happen at a lower rate, though.
In short, biochemicals and liquids seems much more important conditions for a high probability of abiogenesis to me.
Now, if you manage to capture a lava creature from the many volcanoes that taps into the life teeming innards of our planet the quoted description above predicts, I would reconsider.
T-1000:
Says who? I'm not sure why so many people take it for granted that relativistic or even faster-than-light travel is inevitable. FTL travel is generally conceded to be impossible, while relativistic travel is merely fantastically difficult and expensive.
And that doesn't even take into account all the other issues that would be involved in some sort of relativistic bombardment of earth. First of all, the enemy civilization would have to know we were here. Since we've only been able to emit radio signals for less than a hundred years, that's a pretty small portion of the galaxy that could have been alerted. And these signals would be pretty attenuated - it would really, really difficult to pick up "I Love Lucy" from Alpha Centauri, even if you knew what frequency and encoding pattern to look for.
Then, once your enemy civilization made the call to destroy you, they'd have to build a craft that could zip across the galaxy at relativistic speeds, and aim for the relatively tiny Earth. The chance of doing that, even if you somehow avoided any intervening objects (bearing in mind that if the payload hit something the size of a marble while travelling at relativistic speed, well, you'd at least have a pretty big hole in your payload) is infinitesimal. The tiniest error in aim would mean the payload with miss Earth by such a large margin that we'd never even see it. And the idea of a "guided missile" that somehow homed in on Earth strikes me as pretty dubious, given the speeds involved and the very low signal-to-noise ratio discussed above.
Finally, I question the motivation the enemy civilization would have to do this. As discussed above, doing so would be fantastically difficult and expensive. And anyone with the capability to do so could clearly do the cost-benefit analysis... it's also fantastically unlikely that Earth would be motivated to strike the other civ, and be technically capable of doing so. Why go through all the cost and effort to pre-empt something that will almost certainly never happen anyway? Even if you postulate that the enemy civ's morals would allow such a thing, it's just incredibly unlikely.
Suffice it to say that I won't be losing any sleep over the possibility of being hit by a relativistic bombardment from space.
This is another one of those things that mystifies me:
Sure, maybe the technology is a few decades away... but the MOTIVATION to do so is nowhere to be seen. Building the first such probe would cost a lot of R&D and contruction money. Who's going to pay for this? What would they get out of it? The most likely answers to me seem to be "nobody" and "nothing", at least, nothing valuable enough to justify the expense. Which pretty much means it's not happening. And if it's not going to happen here, why do we think it's going to happen anywhere else?
People should keep in mind that we've had sufficient TECHNOLOGY to colonize space since the 60's, yet we haven't done so. Why? Because there's no money in it. The argument against von Neumann probes is similar.
Hmm, and I thought the argument against von Neumann probes was basically the argument against releasing virulent mutant versions of the AIDS, SARS and Ebola viruses; those things are going to face selection, evolve, harvest resources, and (if they survive at all) displace natural life forms. Once they started evolving away from the original design, whoever manufactured the first one would have no control and would be unlikely to obtain any benefit.
Space colonies, on the other hand, if they could be made to work at all, could do all kinds of useful work (i.e. the same kind of arts and sciences people have always done, not just replication). Space elevators would take most of the wasteful rocketry out of getting stuff on and off planets, so that human technology and ecology could expand in continuity with its surface-bound origin, and without annihilating the rest of the biosphere as it did so. I don't think there's any sufficiently-well-reasoned economic argument against colonization, but like any big science project not driven by military rhetoric, it'd be a big target for populist cost-cutting.