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zhamid
2009-Feb-12, 06:39 PM
I understand why scifi movies make aliens look so much like humans (even little green men), but in real life when I look at the diversity of life in our own planet (compare marine life with birds for instance), I can't help but think if there's life in other planets it may be so different from us that we may not even recognize it at first.

Think about it, even if on our own planet if evolution took just a tiny winy bit different path, we may not have had two eyes in the front giving us the ability to see in 3D. We may well have had infrared vision. We could rely on sensors, sensing change in heat / light etc instead of seeing how we do today. We could've had wheels or wings instead of feet (or could have 8 feet). We could be amphibions. Heck some other intelligent life well could have had exoskeleton and spoken a language that we (modern humans) couldn't even hear because we hear sound waves in such a small band!

So what if we do meet aliens but we cant hear their voice at all, let alone eventually learn to fluently speak each others' language. What if we can just sense their presence through indirect means, rather than directly seeing them?

I tend to think there's a higher probability that intelligenet life elsewhere in the universe would be extremely different from us. What do you think? Should sci-fi movies cut back on showing humanoid aliens?

Tarkus
2009-Feb-12, 10:58 PM
I agree Greg Bear described some wierdo lifeforms in his book Space.

swampyankee
2009-Oct-07, 11:32 AM
In most of the movies, the non-humanoid (intelligent) aliens mostly seem to be somehow evil, malignant, and bent on humanity's demise.

Given the number of rather outré body plans and life styles of some of the species on Earth, somebody should tell the writers about tolweb.org and other biological web sites.

Of course, SF writers have more freedom, as they don't have to contend with special effects budgets. I suspect the SF writers' community has more people who actually think about things like what extraterrestrials would look like and how they would behave than does the community of Hollywood script writers.

tnjrp
2009-Oct-07, 11:58 AM
This is a bit of a recurring topic on many science related boards. Here's a recent local thread on the subject:
http://www.bautforum.com/life-space/89023-how-strange-life-space.html

In astrobiology as well, the likely shape of an intelligent alien is of course one of the often speculated subjects... And in fact there are several scientists working on the related fields who have argued that a "Star Trek weird forehead alien" is just about as exotic and far removed from homo sapiens as they can come.

I'd like to think nature is a bit more inventive than that, but then I'm no biologist (let alone astrobiologist). And while I'm not a scriptwriter either, I should think they would like to write in some more exotic stuff as well... However, budgetary limitations tend to curtail their creativity. With the steady march of CGI technology, I suspect we'll see more weird forms in the future tho. Literary scifi after all has many examples thereof.

Barabino
2014-Sep-13, 07:33 AM
I tend to think there's a higher probability that intelligenet life elsewhere in the universe would be extremely different from us. What do you think? Should sci-fi movies cut back on showing humanoid aliens?

Seriously non-vertebrate-like aliens would be difficult to animate (even including computer graphics) and maybe would make poor characters.. :-/

Instead alien "men" can use normal good actors just wearing a couple of rubber ears... :lol:

https://fbexternal-a.akamaihd.net/safe_image.php?d=AQB8ssG5hr7x34nw&w=484&h=253&url=http%3A%2F%2Fwww.treknews.net%2Fwp-content%2Fuploads%2F2014%2F09%2Fstar-trek-premiere-1966-the-man-trap.jpg

swampyankee
2014-Sep-13, 03:16 PM
There is at least one biologist -- I think Simon Conway Morris is the most noted -- who thinks the humanoid aliens are the most likely. I can't summarize his reasoning behind this speculative conclusion. He has much better credentials in biology than do I, so I'm just going to note that other people, with comparable credentials, don't necessarily agree.

Hornblower
2014-Sep-15, 12:15 PM
I remember a magazine article from the early '60s in which the author suggested a centaur-like creature, with solid quadruped support plus hands for doing the things that make us people rather than subhuman animals. He reasoned that our biped stance was a less than satisfactory make-do evolutionary adaptation of the basic four-limbed anatomy which all modern vertebrates had inherited from their primordial ancestors. He felt that these ancestors could just as easily have started with six, as with insects.

As for animating invertebrates, perhaps we need to resurrect the imaginations of Walt Disney and his talented team of animators. They found a way to make a snake shrug his shoulders when a snake has no shoulders. It should be straightforward to extend that to worms, snails, shellfish, etc.

I think this thread was well worth resurrecting after five years of dormancy.

Barabino
2014-Oct-01, 03:36 AM
As for animating invertebrates, perhaps we need to resurrect the imaginations of Walt Disney and his talented team of animators. They found a way to make a snake shrug his shoulders when a snake has no shoulders. It should be straightforward to extend that to worms, snails, shellfish, etc.


It could be correct for the artistic point of view, but not for the xenobiologic POV...

DaveC426913
2014-Oct-03, 02:14 AM
We could've had wheels or wings instead of feet (or could have 8 feet).
It is virtually impossible to have wheels evolve naturally. The nature of an axle is such that it must be a separate element from the main body. How would it get nourished?

I've come across exactly two solutions to this: one fictional and one real-life but highly limited.

In Robert J Sawyer's Starplex, there was an alien that was actually a symbiote of multiple creatures. One was the "chassis", another was the wheel/axle.

In real life, the flagellum of some bacteria have tails can actually rotate like a propeller - a ball and socket arrangement. This only works at the scale of bacteria though because of the square-cube law. The volume of the tail is small enough compared to the surface area that enough nourishment can pass directly through the 2-dimensional body/tail interface even while it's rotating.

Hlafordlaes
2014-Oct-03, 10:14 AM
I am of a mixed view, and can't reconcile until more evidence is in.

On the one hand, it is not far-fetched to posit that interstellar fragments carrying microbes can survive the move from one stellar system to another. This in theory, and due to galactic rotation, could populate a ring at a similar distance from the galactic core that shares fundamental base DNA. Maybe, maybe not, but this would increase the possibility for evolutionary convergences, of which we have examples on Earth starting from that same base. (If so, SETI might do well looking 'ahead of' and 'behind' us.)

This argument can be more tenuously extended to state, say, that carbon is indeed the best candidate given its characteristics to be the core element in all life forms, yielding a more diverse result but perhaps exhibiting some common restraints on the range of options.

Then, of course, there are the mechanical problems that may have a set of best answers (number of legs, eyes) always converging on generally similar solutions.

On the other hand, of course, if life arises from truly distinct means of abiogenesis, total diversity is possible; indeed, unpredictable.

(Star Trek TNG used a species actively seeding planets with DNA to accomplish their take on 'why so many humanoids' in that universe.)

DaveC426913
2014-Oct-03, 03:39 PM
(Star Trek TNG used a species actively seeding planets with DNA to accomplish their take on 'why so many humanoids' in that universe.)

Never found this plausible in any story I've encountered. How does it explain the continuum of DNA across species highly divergent from humanoids?

We know we have genes very much like fish and most other highly diverse Earth life forms, yet those paths diverged a billion years ago.

So, did they seed Earth a billion years ago, before terapods evolved, in which case there's no reason for humanoids to be the outcome? Or did they seed it recently, once the humanoids form was set - in which case, our genetic contribution when compared to other species should stand out?

iquestor
2014-Oct-03, 05:33 PM
Id have to look but I remember reading some arguments from a noted scientist that while ET life might look somewhat exotic to us, it wouldn't likely be so foreign we would not recognize it; he went on to say that if the ET had come from a similar home (rocky planet, carbon based, etc) that we would recognize analogues on that planet to our terrestrial species.

His reasoning was that the senses and body types we see in terrestrial species would likely be common: sight, hearing, touch, taste, etc; and these senses are based on conditions on the planet and sun. eyes would develop to allow the organism to see most well in the available light spectrum, therefore we would recognize them as eyes. same for ears, etc.

He also suggested that organism size would be within some set of parameters as to be somewhat analogous to earth life forms based on gravity, chemistry and bio-mechanics. So we wouldn't expect swift humanoids 100+ feet tall, or microscopic complex mammals.

He also went on to say the characteristics of predators would be similar: stereoscopic vision, efficiency of motion, swift and with claws, teeth and grasping limbs.
Prey would similarly develop defense: poisons, camouflage, speed etc.

in other words, Fins, wings, teeth, claws, hair, feathers, etc are all developed on base characteristics from environmental pressures which should be somewhat universal for so called "earthlike" environments.

Hlafordlaes
2014-Oct-03, 05:40 PM
Never found this plausible in any story I've encountered. How does it explain the continuum of DNA across species highly divergent from humanoids?

We know we have genes very much like fish and most other highly diverse Earth life forms, yet those paths diverged a billion years ago.

So, did they seed Earth a billion years ago, before terapods evolved, in which case there's no reason for humanoids to be the outcome? Or did they seed it recently, once the humanoids form was set - in which case, our genetic contribution when compared to other species should stand out?

Afraid I can't account for fiction. It was a nice episode, I recall.

Barabino
2014-Oct-05, 06:36 AM
Never found this plausible in any story I've encountered. How does it explain the continuum of DNA across species highly divergent from humanoids?

We know we have genes very much like fish and most other highly diverse Earth life forms, yet those paths diverged a billion years ago.

So, did they seed Earth a billion years ago, before terapods evolved, in which case there's no reason for humanoids to be the outcome? Or did they seed it recently, once the humanoids form was set - in which case, our genetic contribution when compared to other species should stand out?

You are right: following this line of reasoning, the origin of panspermia should be some kind of bacteria and not an humanoid...
on the other hand, I appreciate that Star Trek writers tried to explain fictional humanoid aliens at all (pulp SF did not make this effort...)