AVP2 rated at 25%

[Molyneux]

I was thinking of something like a headcrab artillery shell, likely because I just beat Half-Life 2. Not really effective against a military target, but drop a few dozen into a city, and you've got a nice distraction on your hands...

*snip Gordon Frohman*

Wasn't the objective of the Combine to reduce Earth to a mined-out husk, anyhow? Hence the whole stealing-the-oceans-and-atmosphere thing...and it seems they were just keeping what remained of humanity alive as fodder for transhuman troops.

[Junghalli]

Extraterrestrial life forms that originated under similar local conditions as Earth-type lifeforms will likely have DNA.

Why? Lifeforms on Earth have a whole alternate DNA-analog model they could use: RNA, which has a different structure and uses one different base pair (uracil instead of thymine). In fact there's a theory that RNA was the original information storage molecule and DNA replaced it later, relegating to the transmitter role it now serves: a few different twists of evolution and we might still be using it. So yeah, I don't think it's very plausible that a totally alien lifeform would have all the same base pairs that we have and everything.

That does not mean they will be able to parasitize any old thing they come across.

Well, yeah, I won't pretend it's actually realistic.

Since you're the expert, how far from us biochemically should a "true alien" be?

The potential diversity of amino acids is pretty vast IIRC; an amino acid needs an amino group and a carboxyl group and then just about anything can be attached to it. So it's probably pure accident we use the amino acids we do, and a "true" alien would probably use different ones; it couldn't metabolize our protein. I'm less sure about fats and sugars, but those molecules also have a fairly wide variety of possible configurations IIRC.

The Predators could easily be a case of parallel evolution. <snip> Aliens, on the other hand, are parasitic organisms with similar social organization to that of ants.

Actually it wouldn't be all that difficult to explain: xenomorphs started out as an arboreal creature that moved down to the ground in the past for some reason. It looks a little like a human because it's an awkwardly adapted former brachiator, just like us. In fact that's pretty much the only way you could explain how it has hands; it certainly doesn't have enough tool use to justify them.

Which explains why an adult Alien that just happened to parasitize a human has a human skull embedded in its face?

Where is that from? Is it actually movie canon?

Giger didn't design them to be realistic predators, he designed them to be as disturbing and fucked-up as possible to humans.

You're probably right about that.

In-universe, the best explanation for this is that they were designed to be versatile weapons of terror, hence Ridley Scott's comment that he thinks of the ship from the first movie as "an aircraft carrier for bioweapons."

Actually I think there's a much better explanation that that: they were designed specifically for Predator hunts. They make lousy weapons, but as a contestant in some sort of gladiatorial tournament they make much more sense.

Which isn't to say that your ideas for some kind of "natural" Alien species are entirely without merit. Perhaps you could come up with a plausible idea for the original organism before the Pilots or whoever fucked with it. But going by the movies, it seems to me that the only "pure" Alien is the facehugger (well, plus the egg).

Well, I do actually have the essay finished, I'll probably post it to SB momentarily. I can provide a link if you want to take a look.

[Junghalli]

Man, I'm so sick of this "terror weapon" wanking. Oooh, they could drop eggs in behind enemy lines and try to infect people! As if it would be easier to drop eggs and make them land so gently that they don't squish on impact than it would be to simply lob biological or chemical shells. Not to mention the fact that even if this half-baked tactic actually works, now you can't take the planet yourself without spending a lot of time and effort to clear out the infestation.

I've always said it's vastly more plausible that they were designed to be challenging opponents for the Predators in their hunts than any kind of actual military weapon. As something an extreme sport hunter would want to blow away they make good sense.

[Anguirus]

Oh yeah, that's totally realistic. Super-commandoes sneaking behind enemy lines while carrying huge alien eggs.

I was thinking of sticking them on a freighter and bribing the captain, as a matter of fact.

You watch too much sci-fi.

Truly, when considering the rest of the population of this site I am an aberration in this way.

Why? Lifeforms on Earth have a whole alternate DNA-analog model they could use: RNA, which has a different structure and uses one different base pair (uracil instead of thymine). In fact there's a theory that RNA was the original information storage molecule and DNA replaced it later, relegating to the transmitter role it now serves: a few different twists of evolution and we might still be using it. So yeah, I don't think it's very plausible that a totally alien lifeform would have all the same base pairs that we have and everything.

Why not? The same chemical reactions under the same conditions will produce the same results. This is a Darwinian system...DNA probably competed its way to the top. It's not implausible that it could do so on another planet.

The potential diversity of amino acids is pretty vast IIRC; an amino acid needs an amino group and a carboxyl group and then just about anything can be attached to it. So it's probably pure accident we use the amino acids we do, and a "true" alien would probably use different ones; it couldn't metabolize our protein. I'm less sure about fats and sugars, but those molecules also have a fairly wide variety of possible configurations IIRC.

Preds might use a few amino acids that we don't, but what makes you think it wouldn't use ANY of the same ones? It's quite likely that they'll want acidic R groups, basic R groups, neutral R groups, and the ability to form disulfide bonds just like we do.

The potential diversity of life in this universe is, of course, vast. That doesn't mean that our genetic code and our amino acids developed by coincidence. They work. I would be totally unsurprised if an alien life form was similar enough to metabolize Earth proteins...however, I wouldn't expect it to look like an actor wearing makeup either!

Actually it wouldn't be all that difficult to explain: xenomorphs started out as an arboreal creature that moved down to the ground in the past for some reason. It looks a little like a human because it's an awkwardly adapted former brachiator, just like us. In fact that's pretty much the only way you could explain how it has hands; it certainly doesn't have enough tool use to justify them.

What about the facehugger or the egg suggests arboreal to you? (Granted, there are plenty of creatures that change habitats during their life cycle, but the only Aliens that look "arboreal" are ones that burst out of arboreal creatures.)

And how many arboreal creatures on this planet have a humanoid shape? Predators at least have eyes that would benefit from a raised position.

Where is that from? Is it actually movie canon?

Giger's alien head was molded to look exactly like a human skull. The overtly skeletal elements were covered up, with the intended result being, I believe, a subliminally disturbing creature. You can actually see the human-like eye sockets underneath the semi-transparent head covering in the original film.

I'm trying to find a better pic (might hunt for screencaps later) but here are more replicas:

I can provide a link if you want to take a look.

Sure.

[Junghalli]

Why not? The same chemical reactions under the same conditions will produce the same results. This is a Darwinian system...DNA probably competed its way to the top. It's not implausible that it could do so on another planet.

Maybe, but a lot of evolution is a matter of chance. Our fingers are a good example. There's no reason that five fingers is better than four or six, it just happens to have been the number of bones in the fins of the fish that gave rise to the first animal. Our jaws and upper respiratory systems are a similar deal; they may easily have looked rather different if the jawless fishes had evolved a bit differently. Our biochemistry is undoubtedly full of similar accidents.

Since neither of us has much expertise in biochemistry as far as I know I'll just leave it at that for now.

What about the facehugger or the egg suggests arboreal to you? (Granted, there are plenty of creatures that change habitats during their life cycle, but the only Aliens that look "arboreal" are ones that burst out of arboreal creatures.)

I actually discussed that in my essay. I figure the huggers started out as larvae that would crawl out of the trees and move across the ground, seeking a new tree to colonize. As for the eggs, they were probably kept inside the nests (during this stage I figure they'd have had tree nests like birds).

And how many arboreal creatures on this planet have a humanoid shape?

Pretty much all tree-dwelling primates, if you define "humanoid" loosely. When lemurs have to move across ground they stand erect like humans. OK, granted that's a related group so it may not be a great example, but an arboreal lifestyle naturally tends to push organisms in the direction of long limbs and grasping hands. An arboreal creature that moves onto the ground experiences similar pressures to early human ancestors, so it'd be a sensible way to produce something vaguely humanoid.

Giger's alien head was molded to look exactly like a human skull. The overtly skeletal elements were covered up, with the intended result being, I believe, a subliminally disturbing creature. You can actually see the human-like eye sockets underneath the semi-transparent head covering in the original film.

Well, I don't think props are really canon (otherwise canonically it's really a human in suit), although if you can actually see the skull in the movie it is. If you can just see the eye sockets you can explain as a nocturnal creature which's eyes have atrophied.

Sure.

http://forum.spacebattles.com/showthread.php?t=128334

[neoolong]

If you're wondering what the alien skulls look like in the movies, maybe you could pull a screencap from Predator 2's trophy wall.

[Anguirus]

Since neither of us has much expertise in biochemistry as far as I know I'll just leave it at that for now.

Can't say I do, but I have taken Molecular Biology and Cell Biology. It's my understanding that no scientist has yet come up with a theory of how a life form that is fundamentally different from Earth life on a molecular level. But, we are composed of essentially common organic molecules that are known to self-organize under the proper conditions.

An arboreal creature that moves onto the ground experiences similar pressures to early human ancestors, so it'd be a sensible way to produce something vaguely humanoid.

Possibly, but since the needs of the Alien are so fundamentally different from the needs of an Australopithecus, it seems like putting the cart before the horse to call it parallel evolution. In contrast, Predators are extremely similar to humans, so even if it's a huge coincidence it's still plausible that we would be extraordinarily similar to them. They solved similar evolutionary challenges in similar ways.

If you can just see the eye sockets you can explain as a nocturnal creature which's eyes have atrophied.

And you don't think it's odd that the front of an alien creature's head is the same exact size and general shape as the human skull? This also ties into the Predaliens having Predator-like cranial features, though not, I admit, into the Dog/Ox Alien's facial features.

I realize that you find the theory of Aliens taking on characteristics from their hosts personally distasteful, but IMO your excellent essay falls apart when it attempts to rationalize away the existence of the Predalien. It might be more productive to disregard the AvP films totally if you want to advance this hypothesis, because the filmmakers of those entries in the franchise clearly disagree with you.

[Junghalli]

If you're wondering what the alien skulls look like in the movies, maybe you could pull a screencap from Predator 2's trophy wall.

Here's a photobucket of one I've been able to find:



The xenomorph is the one on the top left, I believe. It does not have eye sockets.

[Junghalli]

Can't say I do, but I have taken Molecular Biology and Cell Biology. It's my understanding that no scientist has yet come up with a theory of how a life form that is fundamentally different from Earth life on a molecular level. But, we are composed of essentially common organic molecules that are known to self-organize under the proper conditions.

Well yeah, sure, I think an alien would probably use fats, sugars, proteins etc. as we understand them. I just think they'd probably use a lot of types of those molecules that we don't use, and visa versa.

Possibly, but since the needs of the Alien are so fundamentally different from the needs of an Australopithecus, it seems like putting the cart before the horse to call it parallel evolution.

In terms of locomotion it would be parallel evolution. And if we assume the xenomorph started out as something sort of monkey-like and only developed into an apex predator later it could work. If initially they were opportunistic hunter-scavengers, that actually is a lifestyle not too terribly different from Australopithecus.

And you don't think it's odd that the front of an alien creature's head is the same exact size and general shape as the human skull?

Honestly I can't tell without a screencap where I can see the "skull" in the movie. The only actual xeno skull we see is the one in the Pred ship, which has no eye sockets and does not look human at all. Of course, this isn't conclusive evidence either way; that xeno might have been born from from another eyeless creature.

I realize that you find the theory of Aliens taking on characteristics from their hosts personally distasteful, but IMO your excellent essay falls apart when it attempts to rationalize away the existence of the Predalien. It might be more productive to disregard the AvP films totally if you want to advance this hypothesis, because the filmmakers of those entries in the franchise clearly disagree with you.

Well, in the essay I actually do basically admit "OK, the ones in AvP can take on the characteristics of their hosts, let's just assume the Predators gave them this ability and the rest is natural."

[Anguirus]

I just think they'd probably use a lot of types of those molecules that we don't use, and visa versa.

Quite possibly. The Predator probably takes some interesting shits when it eats cattle.

Honestly I can't tell without a screencap where I can see the "skull" in the movie. The only actual xeno skull we see is the one in the Pred ship, which has no eye sockets and does not look human at all.

I believe they did ditch the eye sockets later, but the shape of the front of the skull is still virtually the same.

I can't seem to find a good screencap anyway, so forget it.

Well, in the essay I actually do basically admit "OK, the ones in AvP can take on the characteristics of their hosts, let's just assume the Predators gave them this ability and the rest is natural."

But then you are faced with the question of why a Predator-influenced Alien with the characteristics of a human host is nearly identical to a "normal" Alien that just happens to come out of a human host.

[Junghalli]

Quite possibly. The Predator probably takes some interesting shits when it eats cattle.

Yeah, it would probably contain substances that for him are toxins, not to mention it would have the nutritive content of cardboard or, at best, cardboard with lard on it. Assuming it'd be edible at all.

This is why I tend to view it as evidence for panspermia in Alien-verse: because otherwise he'd really have been much better off just carrying his own trail rations.

I believe they did ditch the eye sockets later, but the shape of the front of the skull is still virtually the same.

Nothing that can't be explained by convergent evolution. Our jaws are a fairly efficient shape for chewing (and notice the shape of the back of the jaw is definitely not human), and as an intelligent animal it probably needs a fairly large brain case. The real puzzle is why the head needs to be so long. Maybe it was originally an adaptation for carrion-eating, like a vulture's long neck. Or maybe it's where the muscles for the inner jaws anchor.

But then you are faced with the question of why a Predator-influenced Alien with the characteristics of a human host is nearly identical to a "normal" Alien that just happens to come out of a human host.

True. My theory was more of a "what if" than "I'm sure it must have happened this way".

[Anguirus]

The real puzzle is why the head needs to be so long. Maybe it was originally an adaptation for carrion-eating, like a vulture's long neck. Or maybe it's where the muscles for the inner jaws anchor.

Didn't Anchorpoint have some good speculation on this? I seem to recall the hypothesis that it's covered with sensory organs.[/quote]