Maybe the old scifi books and movies were right.

[Gawdzilla]

May I preface this post by saying that I don't give the following scenario a very high probability. But being a skeptic means, to me, being prudently skeptical of the conventional wisdom no matter what the source.

Could there not be some slim chance that "humanoid" is a "popular" body shape for intelligent beings, not just on Earth but on Earth-like planets elsewhere? A "grasping appendage or three" is considered important to the development of intelligence, and one handy place to put them on the end of an arm for easy of manipulating objects. And so on for the other obvious characteristics of the humanoid shape. AAnn, thranx, Kzin, Motie, red Barsoomians, all unlikely, but not impossible.

[MG1962]

The body plan is going to have more to do with what the creature has adapted to do rather than potential intelligence

Example as well as man, a couple of the more intelligent creatures on the planet are dolphins and elephants, and you would agree that their body shapes are very different to man

Could either of these creatures go on to develope higher intelligence...who knows, we need to go out into space, find some smart aliens and see what they look like

[Bikewer]

Larry Niven, in "Footfall" had intelligent aliens built on a rather Pachyderm-y model, with bifurcated trunks ending in more complex grasping appendages.
Fairly clever, I thought.

[Yuri Nalyssus]

we need to go out into space, find some smart aliens and see what they look like
But would we be able to recognise them if we found them? :cool:

Yuri

[Cainkane1]

But would we be able to recognise them if we found them? :cool:

Yuri
We would if they were using shaped metal tools.

[Fnord]

We would if they were using shaped metal tools.

What if their planet does not have as great an abundance of metal ores near its surface as does Earth?

Would stone tools be a sufficient qualifier of 'higher intelligence'? What are the current criteria? Tool-making, written language and use of fire?

Seriously, I'm asking.

[MG1962]

What if their planet does not have as great an abundance of metal ores near its surface as does Earth?

Would stone tools be a sufficient qualifier of 'higher intelligence'? What are the current criteria? Tool-making, written language and use of fire?

Seriously, I'm asking.

I can recall a wonderful short story in which these aliens capture a human and put him in their zoo. Despite his best efforts to show his intelligence he fails

Eventually he captures the equivalent of an alien rat puts in a cage he made and feeds it some of his food

The aliens are shocked...release him with apologies and explain that in the experience only intelligent life forms make pets of lower life forms

Always thought that was an interesting idea

[JoeTheJuggler]

There's a lot of evidence that evolution converges on similar solutions given similar physical constraints. (We should see fish-shaped creatures that live in water, even if they're birds or mammals. We'll see similar kinds of limbs, various kinds of eyes that evolve again and again, etc.)

I don't think there's any evidence that a humanoid form has evolved more than once on our planet. So I would say it's unlikely to be common, but we don't really know.

ETA: Also what exactly is meant by "humanoid"? Were bi-pedal dinosaurs (or any other bi-pedal tetrapod) "humanoid"? If so, it seems we're using the wrong term. If not, what is humanoid if it's not the same as just saying some portion of our phylogeny--that is a term that describes a form that only evolved once?

But again, convergence does seem to be a pretty big thing in evolution.

[Safe-Keeper]

Anyone read The Swarm?
In The Swarm, humanity is attacked by an intelligent kind of "cloud" underneath the surface of the Ocean, an entity made up of particles that combine to form a kind of amoeba. This entity is unaware of the fact that humans are intelligent, despite our ships, planes and whatever else it experiences from under the sea. They simply do not know about our space program, satellites, advanced computers, etc. Call it far-fetched (even the characters in the book do;)), but as a starting point for a philosophical train of thought, it works.

One of the main characters likened it to insects. They can build the most spectacular hives (not to mention spider and their webs), but they are not in any way intelligent beings.

[JoeTheJuggler]

What if their planet does not have as great an abundance of metal ores near its surface as does Earth?

Would stone tools be a sufficient qualifier of 'higher intelligence'? What are the current criteria? Tool-making, written language and use of fire?

Seriously, I'm asking.

I'm not sure what this has to do with the OP.

You seem to be confusing "humanoid" with "higher intelligence". I think the question is whether convergent evolution would favor a particular form ("humanoid").

[TSR]

.
Check out Piers Anthony's Cluster series, esp. Kirlian Quest. Non-humanoid intelligence abounds -- I am kind of partial to the way other sapients are noted by non-quotes speech:

"say something in Slash!"

/something/
.

[GlennB]

Well, if "intelligent being" means pottering about the surface of a planet building things then I'd say yes, they will look pretty similar. Even opposable tentacles are a bitch when it comes to precision engineering. Their weatherproof personal transport will tend to have 4 wheels too, because 4 wheels makes sense.

This isn't to say that engineering skills are a prequisite to earning the title intelligent though. It's just that without them a species can't cure its ailments, improve its environment, wage war and so on.

[Fnord]

I'm not sure what this has to do with the OP.

You seem to be confusing "humanoid" with "higher intelligence". I think the question is whether convergent evolution would favor a particular form ("humanoid").

Sorry to have invaded your thread. Never mind the questions, then.

[Brian-M]

Personally, I'm looking forward of meeting a race of sapient cephalopods.

I can recall a wonderful short story in which these aliens capture a human and put him in their zoo. Despite his best efforts to show his intelligence he fails

Eventually he captures the equivalent of an alien rat puts in a cage he made and feeds it some of his food


I remember that story. It wasn't just one person, but many. They'd crash landed on a planet covered in some kind of spongy fungus and bacteria that ate up all their clothes and gadgets.

Apparently the alien's philosophy was that only sapient beings keep other creatures as pets... which is why keeping a pet "rat" demonstrated their sapience.

[Andrew Wiggin]

.
Check out Piers Anthony's Cluster series, esp. Kirlian Quest. Non-humanoid intelligence abounds -- I am kind of partial to the way other sapients are noted by non-quotes speech:

"say something in Slash!"

/something/
.

Especially good for descriptions of alien mating habits, of the squishy, tentacular yet strangely erotic variety. Almost every main character mates while in alien form at some point or another. I seem to remember someone saying that most of the galaxy, independent of species, was somehow related to Flint of Outworld, who managed to get around in true travelling salesman fashion in the first book.

A

[MG1962]

Personally, I'm looking forward of meeting a race of sapient cephalopods.




I remember that story. It wasn't just one person, but many. They'd crash landed on a planet covered in some kind of spongy fungus and bacteria that ate up all their clothes and gadgets.

Apparently the alien's philosophy was that only sapient beings keep other creatures as pets... which is why keeping a pet "rat" demonstrated their sapience.

Thanks for the correction. Any idea what that was called or the author? It must be 25 years since I read it. Would be nice to revisit

[aggle-rithm]

Thanks for the correction. Any idea what that was called or the author? It must be 25 years since I read it. Would be nice to revisit

I just remember that the ship they were in was called the Lodestar. They built the cage for the rat because they wanted to prove their intelligence, but the aliens assumed it was part of a mating ritual and just moved some women in with them.

And it wasn't so much keeping pets as it was keeping lower life forms in captivity (as the aliens were doing with the humans) that was the proof of their intelligence.

[Brian-M]

Thanks for the correction. Any idea what that was called or the author? It must be 25 years since I read it. Would be nice to revisit


No idea. I think I read it somewhere in the last 10 to 15 years, but I don't remember the title or author. (Hell, I have trouble remembering the title and author of books I've just read.)

I just remember that the ship they were in was called the Lodestar. They built the cage for the rat because they wanted to prove their intelligence, but the aliens assumed it was part of a mating ritual and just moved some women in with them.

And it wasn't so much keeping pets as it was keeping lower life forms in captivity (as the aliens were doing with the humans) that was the proof of their intelligence.


If you're trying to mess with us, it won't work.

[Silly Green Monkey]

You're remembering wrong, they got the last woman moved in with the last two men by weaving baskets. The mouse-thing was caged because it bothered the woman, that proved their intelligence because only intelligent beings keep other beings in cages.

[Andrew Wiggin]

You're remembering wrong, they got the last woman moved in with the last two men by weaving baskets. The mouse-thing was caged because it bothered the woman, that proved their intelligence because only intelligent beings keep other beings in cages.

Proving my intelligence just got a lot kinkier...

A

[Correa Neto]

Personally, I'm looking forward of meeting a race of sapient cephalopods.
...snip...


So, you, for one, are eager to bow before your Zardalu masters?

[Mikemcc]

The body plan is going to have more to do with what the creature has adapted to do rather than potential intelligence

Example as well as man, a couple of the more intelligent creatures on the planet are dolphins and elephants, and you would agree that their body shapes are very different to man

Could either of these creatures go on to develope higher intelligence...who knows, we need to go out into space, find some smart aliens and see what they look likeTheir body shape might not be similar, but their skeletal structures are similar since they are from the same evolutionary branch.

There have been very different structures used here on earth though with fewer or more limbs. About the only thing we can definitely discount for intelligent life is an exo-skeleton (at least using the same compounds for their structure as terrestrial creatures). So no giant bugs!

[Gawdzilla]

Larry Niven, in "Footfall" had intelligent aliens built on a rather Pachyderm-y model, with bifurcated trunks ending in more complex grasping appendages.
Fairly clever, I thought.

I appreciated the fact that he didn't just do another human-shaped B.E.M. for that book.

[Gawdzilla]

ETA: Also what exactly is meant by "humanoid"? Were bi-pedal dinosaurs (or any other bi-pedal tetrapod) "humanoid"? If so, it seems we're using the wrong term. If not, what is humanoid if it's not the same as just saying some portion of our phylogeny--that is a term that describes a form that only evolved once?

But again, convergence does seem to be a pretty big thing in evolution.

As you point out, "humanoid" is a judgment call. But the 'head, two "arms" and two "legs" style' is a general guideline. I think E. E. "Doc" Smith was brave enough to add non-humanoids to his list of heros, "Worsel", et al., but "humans" were the stars even in the Lensman series. We just like us better than anybody else.

[HansMustermann]

Well, I already wrote a couple of long rants on the topic here:

http://forums.randi.org/showthread.php?t=138331

so I'm not going to do the whole exercise all over again. Basically the short story is that I believe that any sentient alien species will have a basically human layout. Even if they might have a bifurcated trunk instead of arms, they will at least have a head, the eyes mounted on it, will not be sentient hives or amorphous blobs, etc.

[Correa Neto]

Dawkins' Ancestor's Tale last chapter (I guess it was the last one, I'm sure it was on of the last ones) had a nice explanation about convergent evolution and features one would expect or not to see in a re-run of evolution on Earth. This is relevant to the discussion at this thread.

Some features (mouths, eyes, wings, legs, echolocation, etc.) evolved independently in a number of genus. Basically it has to do with their cost/benefit ratio and mechanical (better write biological?) feasibility. So, one might suppose that on an Earth-like planet, beings with some of these features would be present. A sentient species capable of developing a technological civilization would need a brain (I'm not sure if all the data processing could be made by tissue scattered along the body), organs to receive sensorial data about its surroundings, some sort or members to manipulate objects, a mouth, some method to communicate with other individuals of its species (possibly through sound) and possibly some members to move around. I guess that's how far one can go.

I think hypothetically such sentient alien beings may have six members, being centaur-like or maybe have radial simmetry instead of lateral symmetry. And why not exoskeletons? The limits of an arthropod's size here on Earth are imposed by the oxigen level of the atmosphere and the ways these animals extract oxigen from the atmosphere and distribute along their tissues. One can imagine that evolution at other Earth-like planets might result in creatures with exoskeletons and lungs.

Humanoid aliens are possible, but that's not the only possibility.

[HansMustermann]

Creatures with exoskeleton and lungs do exist. For example, spiders.

[Hellbound]

Hmmm. Interesting idea just occured to me, and I need a check on the science.

There was a theory I heard a while back that some of the larger dinosaurs had "secondary" brains in their hindquarters. I don't know if that theory has held up, though. I am curious if anyone has any info on that.

Regardless, what would be the possible of an intellignet creature evolving with multiple brains? Any speculation on how that would work? Perhaps one brian that runs functions similar to our higher though processes, with a secondary that controls reflexes and autonomous functions?

Any thoughts? Purely speculative, I know, but since we're speculating anyway :)

[dogjones]

And why not exoskeletons? The limits of an arthropod's size here on Earth are imposed by the oxigen level of the atmosphere and the ways these animals extract oxigen from the atmosphere and distribute along their tissues. One can imagine that evolution at other Earth-like planets might result in creatures with exoskeletons and lungs.



You're forgetting the Square-Cube Law (http://www.buzzle.com/articles/square-cube-law.html) though.

[ellindsey]

The theory of the 'second brain' in dinosaurs is pretty much discredited last I heard. It's thought that the swelling in the spinal cavity housed something similar to the glycogen body that birds have in their hips. The exact purpose of this organ is unknown, but it isn't a second brain.

Concentration of neural functions in one part of the body, near the sensory organs, seems to be a response to how slow nerves are. I have wondered what life might be like on a world where cells somehow evolve the ability to lay down continuous threads of copper or some other conductive material and use direct electrical signaling to transmit neural impulses instead of the relatively slow mechanic of membrane depolarization. With that biological trick the speed of neural impulses would become much less of an issue.

[Correa Neto]

Creatures with exoskeleton and lungs do exist. For example, spiders.
OK, but are they as efficient as those from vertebrates? And the systems wich distibute oxigen to the rest of the body, how efficient they are?

You're forgetting the Square-Cube Law though.
Sure, but we must remember that there were huge aquatic arthropods in the geologic past, such as some eurypterids. Not to mention that at an Earth-like planet where g<9.8m/s*2 things may be different. At last but not least, we must ask what would be the smallest possible body size for a sentient species capable of creating a technological civilization. If its around 1m, well, there were in the past terrestrial arthropods about this size (Arthropleura may have been above 2m).

[Seismosaurus]

Hmmm. Interesting idea just occured to me, and I need a check on the science.

There was a theory I heard a while back that some of the larger dinosaurs had "secondary" brains in their hindquarters. I don't know if that theory has held up, though. I am curious if anyone has any info on that.

Regardless, what would be the possible of an intellignet creature evolving with multiple brains? Any speculation on how that would work? Perhaps one brian that runs functions similar to our higher though processes, with a secondary that controls reflexes and autonomous functions?

Any thoughts? Purely speculative, I know, but since we're speculating anyway :)

I had an ide for a story once called "Pen Pals". Would have features two people writing to one another. The idea was that it seems like their relationship is a little off... you'd become gradually aware that they live in a similar sort of place... then that it's the exact same place, even the same house. The twist in the end would be that it's an alien whose species has two brains, each with a wholly distinct personality, with one brain awake and in control of the body during the day and the other awake and in control during the night. With no way of ever "meeting", people talk to their "other half" through letters, taped messages, etc.

[GreyICE]

Well, I already wrote a couple of long rants on the topic here:

http://forums.randi.org/showthread.php?t=138331

so I'm not going to do the whole exercise all over again. Basically the short story is that I believe that any sentient alien species will have a basically human layout. Even if they might have a bifurcated trunk instead of arms, they will at least have a head, the eyes mounted on it, will not be sentient hives or amorphous blobs, etc.
But you never explored why not. You just sort of stated things. For instance, imagine a species that evolved similar to ants. There could be a sentient 'queen' and non-sentient drones. There would be many advantages to having progressively more intelligent 'queens' which could direct low-resource drones. Communication with the queen done chemically might take entire seconds, but if you look at the number of successful wars fought without a commander, well, there must be some advantage to a general strategist who can outthink the opposition, even with slow control.

So I don't see why a hive structure would be impossible. And, in fact, such a queen would have very little need to be mobile or resemble us in much of any way.

I can actually see a lot of advantages to having non-sentient drones (lower resource consumption, the brain is a hog, faster gestation times, etc.) guided by a sentient.

Similarly, you just sort of speculated that the mouth and respiratory system will be on the head. But unlike eyes, where you had a good reason (high bandwith), breathing takes up almost no bandwidth at all. Neither does eating, particularly. In fact I would not be the least bit surprised if another species developed a 'tasting' appendage separate from the eating one. Testing for poisons by sticking the object in your mouth is just a general bad idea, and I can think of many better designs.

Similarly, limbs. While 6 is a design that never particularly caught on on earth, there's a lot of advantages to having 4 running limbs and two manipulator limbs. Having in excess of two manipulator limbs could be plenty useful as well.

As I said, I just don't buy the argument. Life is too complex to say that we came up with the 'one true best design.' There will be commonalities (shortness of sight organs to brain seems likely) but there will be large differences.

[HansMustermann]

Well, I was thinking more of the SF device of a hive-type-brain, you know, the distributed networked intelligence kind, rather than just division of labour. But to address that objection:

1. In that case, basically, it just makes my main point, which was about the general body layout and structure: you have the actual intelligence concentrated in a bunch of neurons around a high speed hub. In the queen, duly noted. So we'd communicate with her and she'd still have a largely terrestrian layout of her body. You know, with that brain in ahead, eyes near it, mouth up front, etc.

2. Workers, drones, queen, etc, tend to be modifications of the same organism. E.g., worker bees can actually lay eggs in a pinch through their stinger.

So I don't expect their body layout to be fundamentally different from the queen's.

3. The most reliable measurement of intelligence at the moment seems to be basically number of brain neurons divided by number of inputs to the brain. IIRC humans are at 20, cats are 5, dogs are 4. (But don't quote me on the exact numbers.)

If those drones grow past a size, to have even the basic intelligence of a dog in any individual one, the size of the brain will necessarily have to increase too. If nothing else, to deal with the sensors from the bigger body. And distances increase, so the usefulness of remote nodes drops. So for them too the brain would have to be centralized, and the other considerations would apply just as well.

So for them too it makes sense to have a basic terran-like body layout.

4. The usefulness of those dumb workers decreases sharply, the dumber they are. You can't have them drive X-Wings or even perform sophisticated tactical maneuvers, if they come at basically the level of hard-wired carrying food and following chemical trails, and that queen can't remote-control them beyond scent range for the smarter stuff.

To put it otherwise, for a general it is of major use that those soldiers carrying out the orders do have a human brain. They'd use dogs instead, if that worked better.

If that species is going to get an edge out of a bigger brain, I'm affraid that having it in the workers actually makes more sense than having it in the queen only.

[HansMustermann]

Similarly, you just sort of speculated that the mouth and respiratory system will be on the head. But unlike eyes, where you had a good reason (high bandwith), breathing takes up almost no bandwidth at all. Neither does eating, particularly. In fact I would not be the least bit surprised if another species developed a 'tasting' appendage separate from the eating one. Testing for poisons by sticking the object in your mouth is just a general bad idea, and I can think of many better designs.

The mouth had been addressed lower in that thread, partially by Gagglegnash too.

1. It's incredibly useful to have some kind of eye-to-teeth coordination in the earlier stages of evolution. Even for a herbivore, it's useful if you can see what goes into your mouth.

2. Tasting, actually fits the simplicity design of life on Earth. A lot of inputs are more of the "stop what you're doing right now" or "continue, it's the right stuff" kind, than the kind where you need to plan to taste first, then turn around and eat the same thing. There is no separate step of tasting something before you eat it, in non-sentient critters. It's just final test tacked on the process of eating.

Plus, the way conditioned reflexes work, an animal which has a separate appendage, could learn to not taste the things that taste bad, but eat them anyway. It being built the way it is, is a fail-proof design.

Same as you don't have an extra organ for testing bushes for thorns before you eat them, or the water for temperature before you go in it. The whole design requires no conscious planning or discrete steps, and just has a bunch of sensors everywhere that go "stop that right now" or "go on, it feels good." It's a very robust design.

Similarly, limbs. While 6 is a design that never particularly caught on on earth, there's a lot of advantages to having 4 running limbs and two manipulator limbs. Having in excess of two manipulator limbs could be plenty useful as well.

Except again see my requirement that it has to come from evolution, and not just magically appear in its final form. Our species with 2 running limbs and 2 manipulators comes from species which have 4 running limbs, with two of those limbs ending up modified into something else. Something with 4 running limbs and 2 manipulators would have to evolve from a species with 6 running limbs, which, as you've said, was never particularly successful on the Earth and above insect size.

The extra complexity and coordination needed for 6 running limbs are probably not worth it. It's useful to have more limbs in insects, because basically each leg has its own brain node and they're rather autonomous. Having a bunch of legs that try to walk on their own and with little coordination between them, seems to work well with 6 legs or more, and gripping or adhesive legs at that. With a central nervous system, four may well be actually the better solution.

[blutoski]

But would we be able to recognise them if we found them? :cool:

Yuri

Yeah... I'm thinking of Solaris. The alien is probably intelligent, but totally incomprehensible. It's a life form... or something... probably.

[GreyICE]

Well, I was thinking more of the SF device of a hive-type-brain, you know, the distributed networked intelligence kind, rather than just division of labour. But to address that objection:

1. In that case, basically, it just makes my main point, which was about the general body layout and structure: you have the actual intelligence concentrated in a bunch of neurons around a high speed hub. In the queen, duly noted. So we'd communicate with her and she'd still have a largely terrestrian layout of her body. You know, with that brain in ahead, eyes near it, mouth up front, etc.

2. Workers, drones, queen, etc, tend to be modifications of the same organism. E.g., worker bees can actually lay eggs in a pinch through their stinger.

So I don't expect their body layout to be fundamentally different from the queen's. Don't buy it. The drones would determine most of the physicality of the layout, as in what was the most convenient for their tasks. The physical body of the queen, except as related to communication and egg laying, would be highly secondary. That's going to result in something very different from us.

3. The most reliable measurement of intelligence at the moment seems to be basically number of brain neurons divided by number of inputs to the brain. IIRC humans are at 20, cats are 5, dogs are 4. (But don't quote me on the exact numbers.)
It's better to say that there's no reliable measures of intelligence.

If those drones grow past a size, to have even the basic intelligence of a dog in any individual one, the size of the brain will necessarily have to increase too. If nothing else, to deal with the sensors from the bigger body. And distances increase, so the usefulness of remote nodes drops. So for them too the brain would have to be centralized, and the other considerations would apply just as well.

So for them too it makes sense to have a basic terran-like body layout.

4. The usefulness of those dumb workers decreases sharply, the dumber they are. You can't have them drive X-Wings or even perform sophisticated tactical maneuvers, if they come at basically the level of hard-wired carrying food and following chemical trails, and that queen can't remote-control them beyond scent range for the smarter stuff.

To put it otherwise, for a general it is of major use that those soldiers carrying out the orders do have a human brain. They'd use dogs instead, if that worked better.

If that species is going to get an edge out of a bigger brain, I'm affraid that having it in the workers actually makes more sense than having it in the queen only.
Wow. You're totally misapplying evolution. For most of human history and our evolution a complex tool has been 'a sharp stick' and a complex tactical maneuver was 'wait in the bushes until the other tribe walks by.'

X-Wings were not a big feature.

For 90% of what primitive man did with our expanded brains, we'd have been better off with a few high resource consuming 'thinkers' and low resource consuming 'drones.' Apes had no ability to work that way, so we didn't evolve that way. That doesn't mean some other species won't.

And yes, it'll probably become a disadvantage before the 'electricity' stage of development, but by that point it's a tad late.

[HansMustermann]

Apparently for at least the start of the evolution towards Homo, being able to out-wit a predator was a big factor for why those apes survived the change of their environment. So, yes, I would consider intelligence to be a factor even when it mattered.

A species of dumb pre-programmed drones, would not suddenly discover how to do something new like that.

Or, while apes and other animals make ad-hoc tools and then discard them, a thing that only Neanderthals and Homo Sapiens did was plan ahead. It's the only two species we know of that would make a tool to make another tool with, and then keep both for future use.

I don't see how pre-programmed dumb drones would do that. Short of taking a trip back to the queen each time, so the actual intelligence can tell them what to do next. Which doesn't strike me as too efficient.

Another big factor was, basically, flexibility and adaptability. We and the Neanderthals the only species which thrived in as broad a range of environments, preyed on such a wide range of species, and dealt with as wide a spectrum of predators, and generally basically improvised whatever worked for a given problem.

And basically we out-competed the Neanderthals because we were better gatherers, partially also because we learned how to cook food. And past one point because we could learn to use missile weapons. Although nothing in a human's construction is pre-programmed for using a bow and applying the Archer's Paradox correction. That's a moment where it mattered a lot for which species goes extinct and which survives.

Even they before us, were able not just to use a sharp stick, but use hunting tactics that aren't particularly built-in. E.g., using sticks as an extension of the fingers or beak is one thing, but making a boar charge you and sticking your spear's butt in the ground and aiming the tip so the animal impales itself on it, is anything but trivial for a species that lacks any comparable natural weapons. E.g., acting as a group to bring down something as large as a mammoth, or using traps for smaller stuff, and so on.

We're a species which is able to use a totally arbitrary and learned language, to convey that kind of information to future generations. And they're intelligent enough for that to work.

Even if you want to place all such intelligence and creativity in a queen, you need pretty smart and flexible workers to actually understand and correctly apply all that.

Plus there come other uses for a big and flexible brain. For example, we're a species which is harder to fool by disruptive camouflage than anything else. For example, apparently a large drive for bigger brain and better eyes in primates was detecting snakes, something many other species have major trouble doing. For example, again, just the fact that you can learn something unrelated to normal ape business as using a bow and doing ballistics and corrections for wind and lead in your head. Worse than an inertial lead computer, sure, but better than the Neanderthals who never seemed to have used any missile weapons even in zones where they had been in contact with bow-using Cromagnons for thousands of years.

And so on, and so forth.

Basically those drones still will need a central nervous system, even if not as advanced as the queen's. And not quite the hard-wired one. Because otherwise they're too far from the queen most of the time for her to do all those tasks from them.

[GreyICE]

Apparently for at least the start of the evolution towards Homo, being able to out-wit a predator was a big factor for why those apes survived the change of their environment. So, yes, I would consider intelligence to be a factor even when it mattered.

A species of dumb pre-programmed drones, would not suddenly discover how to do something new like that. A single smart queen might very well. Honestly, do you really think that discovering how to out-wit a predator involved the lone hunter, sharp stick clutched bravely in hand, face to face with a Bengal Tiger in 1-on-1 combat?

Give me a break. Of course not. Human versus tiger, human gets eaten.

Most of how we avoided predators was strategy. Cover your scent trail. Lay traps for the tigers, kill them to keep them away from the tribe. Create dens and guard them. Watch over people as they're gathering.

These are strategies. They're as runnable by a centralized intelligence as a non-centralized one. Sure, they might lose a few more drones on 1-on-1 cage matches versus predators than they otherwise would. But centralized planning still rocks, and specialized 'warrior' drones to guard gatherers is just something humanity couldn't do.

I really think this boils down to what a lot of science fiction authors have noted - limited imagination and foolish romanticism is our greatest weakness.

Our 'design' is really just not that good. It's certainly not good enough to make it the 'only model.'

There's some things like 'image processing' that might take some time. Some won't. Low level intelligence drones, as smart as maybe chimps, would be fine.

Meanwhile, there simply wouldn't be the same upper limits on intelligence in the queens that humans have. We had to survive on what we personally could gather. A queen doesn't. That puts the calorie consumption limits on the brains on an entirely different level. It's entirely possible that a queen's brain might evolve to never stop growing, while chemicals stop the growth of brains in the drones early on.

They'd honestly be shocked that we got anywhere when we're so manifestly stupid. They'd probably have a great theory on why the drone-queen model was the only one that worked, since no species could single-handedly gather the calories necessary to maintain their brains.

[Corsair 115]

Larry Niven, in "Footfall" had intelligent aliens built on a rather Pachyderm-y model, with bifurcated trunks ending in more complex grasping appendages.
Fairly clever, I thought.


Speaking of Niven, where would he and Jerry Pournelle's Moties fall on the humanoid scale?

[Andrew Wiggin]

Speaking of Niven, where would he and Jerry Pournelle's Moties fall on the humanoid scale?

Well, two legs, one head, upright orientation, head with two eyes in front, above a nose and mouth, with ears on the sides about even with the eyes. Those are worth a lot of points towards humanoid. On a dark night, with the arms folded...

Posture and gestures are a bit nonhuman due to solid spine and skull being one piece, and connecting to the pelvis with a ball joint, but that's internal. The big alien bits are the non-symmetrical arms and the non-human outlook based on specialization and reproductive biology.

I can't remember, and don't have the books at hand at the moment, but IIRC they at one point in their evolution had bilateral symmetry, but I don't recall if it was consolidation of two arms into one, or one arm splitting into two. Bilateral symmetry would be more points towards humanoid, especially if it was two arms, but even if it was four, as I think we would call Shiva humanoid.

A

[HansMustermann]

A single smart queen might very well. Honestly, do you really think that discovering how to out-wit a predator involved the lone hunter, sharp stick clutched bravely in hand, face to face with a Bengal Tiger in 1-on-1 combat?

No, but it involved some intelligent assessing the environment.

Give me a break. Of course not. Human versus tiger, human gets eaten.

Since you're here, obviously enough of them were smart enough to not get eaten.

Most of how we avoided predators was strategy. Cover your scent trail. Lay traps for the tigers, kill them to keep them away from the tribe. Create dens and guard them. Watch over people as they're gathering.

Except a lot of them involve ad-hoc judgment calls and reactions.

These are strategies. They're as runnable by a centralized intelligence as a non-centralized one. Sure, they might lose a few more drones on 1-on-1 cage matches versus predators than they otherwise would. But centralized planning still rocks, and specialized 'warrior' drones to guard gatherers is just something humanity couldn't do.

Except

1. as a result we had more people to use for other things, if the gatherers could jolly well take care of themselves instead of being a whole team of narrowly specialized roles.

2. _Again_, we're not talking Age Of Empires, but a scenario where those drones need to understand a set of arbitrary rules given by that queen, analyze a bunch of shapes and colours around and decide which rule to apply, and God help you if there's one detail that that queen forgot one detail and they can't improvise.

You just moved the problem from each one improvising for itself, to some queen basically being able to program a robot in detail and get it right the first time. Because they need to function autonomously when they're away. We _still_ can't do that kind of programming well.

In fact, a form of protest in humans is to do exactly what you were told to the letter, but completely missing the spirit or idea. It's a pretty good simulation of what it would be to have such an army of brain-dead drones. And it leads to some spectacular screwup every time.

[Gawdzilla]

Speaking of Niven, where would he and Jerry Pournelle's Moties fall on the humanoid scale?

In the book they note that the Moties probably evolved from the six-limbed critters spotted in the "Zoo", but the basic body plan is defo humanoid to me. Head on top, upright, manipulating limbs on upper corners of the trunk, supporting limbs on the lower corners.

[Ethan Thane Athen]

.
Check out Piers Anthony's Cluster series, esp. Kirlian Quest. Non-humanoid intelligence abounds -- I am kind of partial to the way other sapients are noted by non-quotes speech:

"say something in Slash!"

/something/
.

One of the best attempts at non-humanoid aliens IMHO. Very good series.

[GreyICE]

No, but it involved some intelligent assessing the environment.



Since you're here, obviously enough of them were smart enough to not get eaten. Hans, since you're here, let me let you in on a little something. When two sentences are obviously part of the same thought, separately quoting them and pretending they're two separate things is really dumb.

[HansMustermann]

Hans, since you're here, let me let you in on a little something. When two sentences are obviously part of the same thought, separately quoting them and pretending they're two separate things is really dumb.

So is pulling such an ad-hominem instead of having something intelligent to say on the topic, or blaming others for your being unable to understand why the two halves were answered separately, but I guess we'll both live, eh? ;)

[GreyICE]

So is pulling such an ad-hominem instead of having something intelligent to say on the topic, or blaming others for your being unable to understand why the two halves were answered separately, but I guess we'll both live, eh? ;)
But you can't just split a thought into two halves and expect to respond sensibly to both halves. As I pretty much expect when I see something like that, your second response was just flat nonsense - responding to 'half a thought' usually is.

And it actually wasn't an ad hom, it's an explanation of why I'm not responding anymore. I've adopted a zero-tolerance policy to people mangling my writing.

P.S. Seriously. There's no point in responding to half a thought. And plenty of reasons not to.

[Hellbound]

The theory of the 'second brain' in dinosaurs is pretty much discredited last I heard. It's thought that the swelling in the spinal cavity housed something similar to the glycogen body that birds have in their hips. The exact purpose of this organ is unknown, but it isn't a second brain.

Concentration of neural functions in one part of the body, near the sensory organs, seems to be a response to how slow nerves are. I have wondered what life might be like on a world where cells somehow evolve the ability to lay down continuous threads of copper or some other conductive material and use direct electrical signaling to transmit neural impulses instead of the relatively slow mechanic of membrane depolarization. With that biological trick the speed of neural impulses would become much less of an issue.

Thanks!

I seemed to recall it being discredited, but couldn't remember any details. And my current net access is both slow and cumbersome, so I'm not doing much in the way of research here (I'm currently in an undisclosed, mostly-desert country doing business on behalf of a certain unnamed superpower's land-based military forces ;), in other words, I'm deployed to Iraq with the U.S. Army Reserve).

I had an ide for a story once called "Pen Pals". Would have features two people writing to one another. The idea was that it seems like their relationship is a little off... you'd become gradually aware that they live in a similar sort of place... then that it's the exact same place, even the same house. The twist in the end would be that it's an alien whose species has two brains, each with a wholly distinct personality, with one brain awake and in control of the body during the day and the other awake and in control during the night. With no way of ever "meeting", people talk to their "other half" through letters, taped messages, etc.

That sounds interesting, but I seem to recall a story that used a similar idea...although that wasn't the main plot but something related. Can't recall what story now, but If I think of it I'll shoot you a message, if you're interested. It's probably one of the ebooks I bought from webscription.net, but I have about 400, so it might take me a bit to find it :)

[Silly Green Monkey]

the thread's moved on now, but I found the story--knew I had it around somewhere. It's Bertram Chandler's The Cage.

[ArmillarySphere]

There's also the delightful little tale "They're made of meat" (http://baetzler.de/humor/meat_beings.html)...

[JoeTheJuggler]

As you point out, "humanoid" is a judgment call. But the 'head, two "arms" and two "legs" style' is a general guideline.

Do bipedal dinosaurs qualify as humanoid? What about an insect-like animal (compound eyes, exoskeleton, open circulatory system) that had just 4 limbs?
ETA: What about bears? I don't believe I've ever heard them referred to as "humanoid".

I would think it's a more restrictive term than a head, two arms and two legs. (That sounds like the definition of all tetrapods.)

In sci-fi, it seems to be defined as an organism that can easily be portrayed by a human actor!

Really, though, I think without a very particular definition, I don't think the question is very meaningful. The only thing on Earth we recognize as hominid or even hominoid are primates.

[MG1962]

the thread's moved on now, but I found the story--knew I had it around somewhere. It's Bertram Chandler's The Cage.

Ahh thank you for the effort. How could I forget such a wonderful Australian author

[JoeTheJuggler]

Well, two legs, one head, upright orientation, head with two eyes in front, above a nose and mouth, with ears on the sides about even with the eyes. Those are worth a lot of points towards humanoid. On a dark night, with the arms folded...

Posture and gestures are a bit nonhuman due to solid spine and skull being one piece, and connecting to the pelvis with a ball joint, but that's internal. The big alien bits are the non-symmetrical arms and the non-human outlook based on specialization and reproductive biology.

I can't remember, and don't have the books at hand at the moment, but IIRC they at one point in their evolution had bilateral symmetry, but I don't recall if it was consolidation of two arms into one, or one arm splitting into two. Bilateral symmetry would be more points towards humanoid, especially if it was two arms, but even if it was four, as I think we would call Shiva humanoid.

A
Good points.

For a definition to be useful, it should include all the characteristics necessary to include all the objects of the class and exclude objects that aren't in the class.

A lot of the stuff you list would include pretty much every bipedal tetrapod on Earth, but we don't usually count them as humanoid. Yet it would exclude something exactly like a human in every way but having an extra pair of eyes or a third arm or something with ears not even with the eyes, or nose and mouth in reversed positions or some such.

[JoeTheJuggler]

To follow up a bit. . .

I'm not harping on the definition (just) to be cantankerous. I really think the question should be re-framed.

I think the question should start out more basically. How much convergence can we expect comparing ET evolution to terrestrial evolution? The very basic questions come first. Do we find DNA or some other self-replicating molecule? Do we find membranes, cells, tissues, organs?

I think we can expect to find those things, but even at that level, there are some huge questions it would be tremendously exciting to have answered.

I think questions of how photosynthesis and cellular respiration happen (or energy use in general) would be big ones. Here on Earth we saw a pretty big punctuation in ecological equilibrium when organisms started aerobic energy pathways. Sex seems to have been hugely advantages. I would expect convergence on these sorts of things.

Beyond that, I think given similar physical environmental conditions, we can expect to see recognizable tissues and organs (membranes, structures). I think we would likely see similar or familiar body shapes--streamline for flying or swimming. I think we would likely see eyes (and therefor some form of a CNS). I think we would see familar-looking appendages--fins, flippers, wings, legs.

[HansMustermann]

Well, life was just an extension of some self-replicating chemical reactions that happened in the ocean. At some point those started building essentially a closed test tube around themselves, and increasingly regulating what can go in or out. That's cells.

Actually, my hypothesis is actually a bit the other way around. Fats naturally tend to form a closed bubble, isolating whatever is inside from the big pool of reagents outside. So I expect that the first proteins encoded were simply stuff that formed a hole on such a lipid membrane.

I would expect life everywhere else to start the same. Maybe with other chemicals. But essentially it still has to start with some chemistry that happens in a big ocean, and from there it's a huge advantage to have some control over what's in your test tube. I.e., I would expect it to form cells sooner or later too.

But actually there's a more perverse factor there, IMHO. I'll get to it later.

The second factor is that a star starts actually fairly cool and heats up over time. A planet that doesn't start with a greenhouse atmosphere, would be just frozen solid. One that doesn't switch to a non-greenhouse atmosphere later, will cook, like Venus did.

In Earth's case, that was the transition from a methane and CO2 atmosphere to oxygen.

Life ony other planet, with any other chemistry, though, will have to _somehow_ compensate for their star's gradual change in temperature. Otherwise chances are that there is no single set of substances that keeps working the same at a couple hundred degrees difference. If you don't compensate somehow, your original liquid solvent will turn into steam, and it's the end of the road right there.

Which brings me back to cells. There is a race against time to evolve to closed little systems that can synthetise their own building blocks. Because sometime around the point where your atmosphere changes, so too the chemicals form in your primordial soup might change.

In Earth's case that meant an increasing shortage of naturally forming codons and most aminoacids. If life hadn't evolved to the sophisticated point where it can produce those itself, it would have fizzled right there.

But when you start getting that complex, forming cells becomes a must. It's not just that it's easier to control the composition of that enclosed drop of seawater, but you can also keep everything in close proximity to where it's needed. You have the enzymes that reduce the superoxide right next to the metabolic enzymes that produce it, and you have the produced RNA and aminoacids in the same small drop of water as the ribosome. It's a more robust design than just relying on them floating around in the few trillions of tons of water of the ocean.

[lylfyl]

I had an ide for a story once called "Pen Pals". Would have features two people writing to one another. The idea was that it seems like their relationship is a little off... you'd become gradually aware that they live in a similar sort of place... then that it's the exact same place, even the same house. The twist in the end would be that it's an alien whose species has two brains, each with a wholly distinct personality, with one brain awake and in control of the body during the day and the other awake and in control during the night. With no way of ever "meeting", people talk to their "other half" through letters, taped messages, etc.

This made me think of Robert Forward's Saturn Rukh. The aliens were large manta-type creatures swimming through a gas giant. They had multiple brains with distinct personalities. I want to say that the brains took shifts as well, but it's been quite awhile since I read it.

I tried to Google it, but every site seems to have cut and paste from the same couple of summaries.

[Mark6]

Do bipedal dinosaurs qualify as humanoid?
Note that bipedal dinosaurs, as well as birds (also bipedal) all walked with spine held horizontal. Humans and apes are the only bipedal animals which walk with spine upright. Is that a necessary condition for "humanoid"?

In all fairness, I had seen people who claimed that "humanoid" is a necessary body plan for an intelligent creature, and freely included Velociraptor in that definition.

[Simon39759]

Well, this thread remind me of a site (http://darrennaish.blogspot.com/2006/11/dinosauroids-revisited.html) I read just a few days ago and found interesting, thought I would share.


As far as actually personally contributing to the discussion, well we know that a humanoid body shape do work for an intelligent being (although better for some than others) and, so far, it is the only one we know works.

Everything beyond that will involve quite a bit of speculation but I'd expect the body plan of ET to reflect its evolutionary history with only limited level of convergence, in fact, this convergence might more have to do with basic physiology (regulated body temperature, limited fertility and long life cycle) rather than body plans...

[HansMustermann]

Note that bipedal dinosaurs, as well as birds (also bipedal) all walked with spine held horizontal. Humans and apes are the only bipedal animals which walk with spine upright. Is that a necessary condition for "humanoid"?

In all fairness, I had seen people who claimed that "humanoid" is a necessary body plan for an intelligent creature, and freely included Velociraptor in that definition.

I think most of us don't have a problem with a horizontal spine instead of vertical, if that works. It's more about the general body plan than such fine details.

The raptor or T Rex body plan is basically OK. The arms are really too weak and short for most tasks, and I somewhat doubt that their exact body configuration would allow them to carry large loads in their hands or exert much leverage. But I guess neither is some insurmontable obstacle to evolution.

But technically _I_ wouldn't have that horribly much of a problem even with a modified arachnid body (it's one of the species which got lungs and a primitive circulatory system, and thus could scale to larger sizes than other insects), or a sort of centaur, or whatever.

What I'm more concerned with are some of the wilder flights of imagination that some people are fond of. You know, floating gas sacs in a hydrogen gas giant, telepathic hive species or ocean-sized bacterial colonies that work like a hive, sentient rocks or trees, or indeed whole sentient planets or galaxies, and so on. Things where -- for all the coolness factor and all -- you just have to ask yourself how the heck would evolution create something like that.

That's usually the kind that gets contrasted with Hollywood's "unimaginative" humanoids. I don't think that just making one of the Star Trek aliens walk slanted forward, or even giving them insect antennae and a third pair of limbs would make much of a difference to that crowd ;)

[Simon39759]

Well; you'd need the environment to be complex enough for intelligence to give an advantage. Floating around and being pushed by the winds does not seem like it would generate much selective pressure toward a higher intelligence, let alone the need for prehensile appendages...

No, the packs of giant carnivorous flaying squirrels hunting them, that's another problem.