Do you believe in extraterrestrials?

[Northwest Slobovia]

2) It is vanishingly unlikely that said life will resemble anything familiar to us.

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

[Breadknife]

2) It is vanishingly unlikely that said life will resemble anything familiar to us.

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

I do not wish to speak for Bottle (although in two short points she summarises most of what I've been trying to say), but looking at the level of Kingdoms that we know of on Earth, I might expect that alien trees-of-life would contain both motile (animal-equivalent) and non-motile (plant-equivalent) branches for their multicellular life as well as one or more families devoted to single-cell units, and probably fragment-packages equivalent to our viruses. But this may be assuming too much.

It is of course 'trendy' to imagine "intelligent plants". One or other incarnation of the Triffids in fiction (right now I'm not bothering myself to try to untangle the differing fictional treatments of the meme to work out which, but I'm sure Wyndham's originals from the book were left with an unclear origin, probably seeded from space) is that this is an alien plant that is motile. But it could just as easily be an alien animal that merely has many plant-like qualities. Like a creature that is approaching the design of Venus Fly-Trap from the opposite direction. You may examine its cells and say that they are plant-like (from memory, distinct from animal cells by having a distinctly rigid cell wall), and may even find chlorophyll or its analogue, but that may be the standard model for motile creatures upon its home-world.

We could of course shoe-horn them and their native world's biological samples into animalae/plantae/etc... But given that funghi look like plants yet are apparently more closely (and recently) related to animals, we could easily be fooled into the same sort of classification system as we did back in the period we only had the two-kingdom classification system.

(Indeed, finding out what similarities and what differences our comparative biologies have, including asking any sufficiently communicative aliens how they consider their system (and, once they've thought about it, our own) to be subdivided might reveal some interesting constants and some interesting 'frees'. e.g. if we can get a yay or a nay over whether rigid cell-walls can allow or prevent mobility to the level of the fictional Triffid, or even the Minecrafian 'Creeper'.)

So, yeah, Kingdoms would probably be a close fit for our own at first glance, but still loose around the gusset in so many other ways.. The mix of whether a cell has chloroplasts, mitochondria, etc (or their alien biology analogues) would certainly depend on what happened waaay back along the alien family-tree and might give unexpected results (such as macro-sized single-celled life).


Bilateralism? It probably arose (on Earth) from a single organism that spawned the entire lineage. So imagine if that creature had found itself with trilateralism... An occasionally seen retrospective idea given by some to explain the War Of The Worlds martian war-machines being tripods that the Martians are themselves trilateral (or possibly hexalateral, with alternating "feet dominance" and "arm dominance" w.r.t. each limb, in order). And this affects their whole design philosophy, just like our walking robots are bidpedal (for humoid posture, and to show off), quadrapedal (robotic cheetahs, etc, or down to the simplest one-leg-at-a-time gait that doesn't topple), although both us and the Martians use hexapedal variants as well...

I've seen some rather good speculative biolofy working with a common pentalateral bodyform, made use of in various ways (including posture creating a common choice between two/three feet and three/two arms for those creatures that walk upright), although one needs to consider that this was certainly created under the instruction "make me an alien ecosystem, and make it look alien). And, biologically, is it harder to get a multilateralism (#>2) than 'normal' bilateralism?

It'd certainly be more than a matter of a single germ-cell splitting in two and then each half coordinating the further cell division pattern to create all the mirroring, so maybe it would be less likely. But could an alateralist approach work in its stead? i.e. be a dominant bodyform even unto complex (and, eventually, tool-using) life forms? Possibly if the bilateralist approach did not arise with any advantages that this may have given. And what would be more alien-looking than something that doesn't have symmetry? (Of course, if your alien ends up like a worm with (say) a single arm/effector (and still gets to a tool-using stage, which is debatable) then it may habitually lead or trail that arm, in everyday motion, and thus be symmetric regardless.


When you get to biochemistry, that is where I feel I can be sure about the differences. There will be differences. DNA is our backbone for life (along with RNA, and plasmids and similar things), with sugar-molecules chaining to form the two strands and two pairs of complementarily-fitting nucleotides encoding the information as the 'rungs' of the many-twisted ladder.

I have no doubt at all that independently-arising life will be different. Even if the double-helix is reimplemented (and it isn't instead some other information-packing method), the strands will doubtless be composed of different biopolymeric material and the 'bases' are pretty much guaranteed to not be A-T and G-C. For efficiency's sake (might be a factor in the first battles after biogenesis when it might be easier for the proto-life molecules that don't need to synthesise and auto-cataluse a large variety of 'feedstock' molecules, in order to outcompete the proto-life that currently works with three possible 'rung-pairings', or even something that works best with triploid stranding) that seems to be the minimum necessary complexity. But should a three-stranded system arise the encoding system might also utilise the handedness of A+B+C or D+E+F molecules, in a way that A+B and C+D could not.

Even more generally, under different conditions (note: within a different Goldilocks Zone) the 'xeno-organic' chemistry might well be not carbon-based. Sci-fi likes to make that silicon-based, given its relative position in the periodic table and the natural alternative when looking for such a similarly-slutty bond-former. There are definitely plusses and minuses in looking towards that alternate approach to life. And if it is silicon-based, then those people looking for methane as a sign of biological activity are going to be dissapointed. They might also be looking at the wrong places (wrong temperatures and pressures) for where metalloid-based chemistry best works.

And if the speed of the chemistry (whether still carbon-based or something alternative like silicon, that can still form hyperconjugation/etc) is different because of the common components are different (logically, I suppose, with heavier atoms it should be slower) and if the exterior skin of such a being is not 'squishy', you might conceivably mistake the alien ambassador for a small rock or a strangely shaped boulder.


But even without such extremes of alternate-biology, don't go using a "DNA sequencer-onna-chip" device in order to detect life, because you'll probably not be encountering DNA (as we, and the sequencer, knows it). Indeed, if it works then I would be tempted to assume a common heritage (either panspermia upon both worlds, or life-material transferred from one world to the other in the distant past, e.g. via Martian meteorites). Which would be an interesting result.

OTOH, if it crawls/leaps/walks out of a just-landed space-capsule of non-human origin then I think you've found life, regardless of what it looks like and what any potential chemical tests might (given the opportunity) show. (Now you just need to work out what it wants, and be ready to run, attack or await a more expert communicator. I'll be just over here, behind the giant robot. Our giant robot, that is... why is there another of them? And is that the alien ambassador?)

[Grainne Ni Malley]

Well they did put us here as a science experiment, so yeah.

[Terran Faction]

Well they did put us here as a science experiment, so yeah.

Space Jockeys?

[Grainne Ni Malley]

Well they did put us here as a science experiment, so yeah.

Space Jockeys?

Mala'kak indeed.

[Northwest Slobovia]

So, yeah, Kingdoms would probably be a close fit for our own at first glance, but still loose around the gusset in so many other ways.. The mix of whether a cell has chloroplasts, mitochondria, etc (or their alien biology analogues) would certainly depend on what happened waaay back along the alien family-tree and might give unexpected results (such as macro-sized single-celled life).

I'm thinking of the prok/euk division and autotroph/heterotroph more than anything else. I don't necessarily see why other planets would have analogs beyond that.

When you get to biochemistry, that is where I feel I can be sure about the differences.

Yup. That's why I specified initially unrecognized. I can think of many variations too. I'd very surprised if we encounter anything that doesn't use polymers for storing its genetic information and building its catalysts, because polymers seem so damn convenient for that. (And I mean that in the strict sense of "repeating chemical subunits" and not the loose sense of "plastic".) 'course, that would be a present surprise.

Even more generally, under different conditions (note: within a different Goldilocks Zone) the 'xeno-organic' chemistry might well be not carbon-based. Sci-fi likes to make that silicon-based, given its relative position in the periodic table and the natural alternative when looking for such a similarly-slutty bond-former. There are definitely plusses and minuses in looking towards that alternate approach to life.

Mostly minuses. Si-Si bonds are surprisingly weak and easily cut by water (and other common polar solvents).

But even without such extremes of alternate-biology, don't go using a "DNA sequencer-onna-chip" device in order to detect life,

Er, yes, thanks. Bottle isn't the only one around here who can tell valine from valium.

because you'll probably not be encountering DNA (as we, and the sequencer, knows it). Indeed, if it works then I would be tempted to assume a common heritage (either panspermia upon both worlds, or life-material transferred from one world to the other in the distant past, e.g. via Martian meteorites). Which would be an interesting result.

I wouldn't rush to embrace panspermia, but I would be very surprised if alien life were identical all the way down (same NAs, same AAs -- or even a mostly overlapping set -- same chirality, same core metabolism). If we found that multiple times, it might make some interesting arguments about the limits of biochemistic, abundance of abiotic precursors, and/or other similar things, though.

OTOH, if it crawls/leaps/walks out of a just-landed space-capsule of non-human origin then I think you've found life, regardless of what it looks like and what any potential chemical tests might (given the opportunity) show.

"Opportunity" is the operative word, given that most of things we've sent to other worlds have lacked a certain "spirit".

[The Independent States]

I wouldn't be surprised if there were aliens out there, but I wouldn't run around screaming that I know they exist.

[Bottle]

2) It is vanishingly unlikely that said life will resemble anything familiar to us.

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

What springs to mind for me is some of the creatures that have been discovered in some of the depths of our own oceans, and how profoundly alien they are to us. The difference between our land-world of mammals and their world of crushing pressure and absolute darkness is only a sliver of difference compared to what we will find if we start comparing our planet to other planets.

So to answer your specifics, I think the lack of bilateral symmetry would go hand in hand with radically different biochemistry; the way we develop, and the reasons why it is "easier" to produce a symmetrical organism than an asymmetrical one, would not necessarily remain constant if the underlying molecular interactions were different.

As for eyes, we already know of plenty of life forms which have no particular need to perceive the spectrum of energy we know as visible light. I would not be at all surprised by alien life which finds such receptors similarly unnecessary, particularly since there's no reason to assume said life would be surface-dwelling.

[The Parkus Empire]

Based on my background in biology, I think 1) It's almost certain that life exists on other planets, and 2) It is vanishingly unlikely that said life will resemble anything familiar to us.

I'm curious to hear your opinion of alien social evolution, because it seems to me that is also imagined as improbably humanlike. Is sentience, as we define it as humans, really likely to exist in extraterrestrial lifeforms? It seems to me that that's as unlikely as aliens having eyes and ears--hell, even more unlikely.

[Breadknife]

Even more generally, under different conditions (note: within a different Goldilocks Zone) the 'xeno-organic' chemistry might well be not carbon-based. Sci-fi likes to make that silicon-based, given its relative position in the periodic table and the natural alternative when looking for such a similarly-slutty bond-former. There are definitely plusses and minuses in looking towards that alternate approach to life.

Mostly minuses. Si-Si bonds are surprisingly weak and easily cut by water (and other common polar solvents).

That's something I meant to address, given that Si-Si 'organics'-friendly (<-originally typed "orangics".. ) environments are likely waterless, so what might be the equivalent "universal solvent" (which doesn't, as you point out, destroy the polysilicates)? If we're just dropping a level on the periodic table then H₂S might be our man, but something tells me it isn't... *cough*


Also forgot to deal with the issues of the eye that you mentioned. Don't they say that (on Earth) it has been independently developed at least seven times, in different evolutionary branches? That's all forms of eye, not just our (pre-)mammallian one, although the cephalopd one is surprisingly similar to ours (only without some of its flaws).

Anyway, I imagine that as long as visible light has been a useful thing to detect (i.e. not if the aliens developed within a somewhat photo-opaque atmosphere¹) that we'd see eyes of some kind or another. Although how recognisable they would be is another question, e.g. are they still paired? Are they still upon what passes for the alien's head? (Assuming that there is a 'head', c.f. Niven's "Puppetteer" race.)

But if visible (or near-visible, from our perspective) light has not been useful, perhaps electrosensitivity is the dominant 'sight'-equivalent sense, perhaps not needing obvious eye-like features. I forget if this is supposed to be part of their biology, but the "Alien" aliens are conspicuously eyeless (well, all natural ones anyway) and may be thus differently-sensing of prey (or, on their original home world, all the very much nastier things that they are prey for) in such ways.

And if we're still welded to the idea of "metalliform" creatures, arising from a vague and admitedly unproven assumption of a silicon-based biology, might that make wandering off into the radio-wave areas of the EM spectrum a viable sense-equivalent? Of course, if your skin is metal-based you're probably effectively shielding internal aerials/parabolic dishes from radio waves, so either external ones (which may be obvious) or radio-opaque patches of skin (which, again, may be obvious, just like the eyeball pokes out through our own skin) perhaps ought to exist. But it still may not be anything like that.


¹ Of course, if an alien atmosphere is photo-opaque to us, it's possibly not so at far infrared or ultraviolet, so actual eyes tuned accordingly could/should/would still develop. Also s/atmosphere/ocean/ if you can either explain or hand-wave away what the equivalent "discovery of fire" moment is in a locale with no fire. e.g. using geothermal vents and the like as natural campfires (and later, natural forges from where there are magma extrusions?). Although if we're already talking about alternate biochemistries then we can look for something else that's equivalent in the alternate environment.

[Grenartia]

It does however increase the volume

Which is equally an argument AGAINST an 'earth 2', because it means planets that might once have been in the 'habitable zone'... will have moved out of it.

Not really. Cosmic expansion really only affects galaxy clusters, IIRC.

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

I do not wish to speak for Bottle (although in two short points she summarises most of what I've been trying to say), but looking at the level of Kingdoms that we know of on Earth, I might expect that alien trees-of-life would contain both motile (animal-equivalent) and non-motile (plant-equivalent) branches for their multicellular life as well as one or more families devoted to single-cell units, and probably fragment-packages equivalent to our viruses. But this may be assuming too much.

It is of course 'trendy' to imagine "intelligent plants". One or other incarnation of the Triffids in fiction (right now I'm not bothering myself to try to untangle the differing fictional treatments of the meme to work out which, but I'm sure Wyndham's originals from the book were left with an unclear origin, probably seeded from space) is that this is an alien plant that is motile. But it could just as easily be an alien animal that merely has many plant-like qualities. Like a creature that is approaching the design of Venus Fly-Trap from the opposite direction. You may examine its cells and say that they are plant-like (from memory, distinct from animal cells by having a distinctly rigid cell wall), and may even find chlorophyll or its analogue, but that may be the standard model for motile creatures upon its home-world.

We could of course shoe-horn them and their native world's biological samples into animalae/plantae/etc... But given that funghi look like plants yet are apparently more closely (and recently) related to animals, we could easily be fooled into the same sort of classification system as we did back in the period we only had the two-kingdom classification system.

(Indeed, finding out what similarities and what differences our comparative biologies have, including asking any sufficiently communicative aliens how they consider their system (and, once they've thought about it, our own) to be subdivided might reveal some interesting constants and some interesting 'frees'. e.g. if we can get a yay or a nay over whether rigid cell-walls can allow or prevent mobility to the level of the fictional Triffid, or even the Minecrafian 'Creeper'.)

1. So, yeah, Kingdoms would probably be a close fit for our own at first glance, but still loose around the gusset in so many other ways.. The mix of whether a cell has chloroplasts, mitochondria, etc (or their alien biology analogues) would certainly depend on what happened waaay back along the alien family-tree and might give unexpected results (such as macro-sized single-celled life).


2. Bilateralism? It probably arose (on Earth) from a single organism that spawned the entire lineage. So imagine if that creature had found itself with trilateralism... An occasionally seen retrospective idea given by some to explain the War Of The Worlds martian war-machines being tripods that the Martians are themselves trilateral (or possibly hexalateral, with alternating "feet dominance" and "arm dominance" w.r.t. each limb, in order). And this affects their whole design philosophy, just like our walking robots are bidpedal (for humoid posture, and to show off), quadrapedal (robotic cheetahs, etc, or down to the simplest one-leg-at-a-time gait that doesn't topple), although both us and the Martians use hexapedal variants as well...

3. I've seen some rather good speculative biolofy working with a common pentalateral bodyform, made use of in various ways (including posture creating a common choice between two/three feet and three/two arms for those creatures that walk upright), although one needs to consider that this was certainly created under the instruction "make me an alien ecosystem, and make it look alien). And, biologically, is it harder to get a multilateralism (#>2) than 'normal' bilateralism?

It'd certainly be more than a matter of a single germ-cell splitting in two and then each half coordinating the further cell division pattern to create all the mirroring, so maybe it would be less likely. But could an alateralist approach work in its stead? i.e. be a dominant bodyform even unto complex (and, eventually, tool-using) life forms? Possibly if the bilateralist approach did not arise with any advantages that this may have given. And what would be more alien-looking than something that doesn't have symmetry? (Of course, if your alien ends up like a worm with (say) a single arm/effector (and still gets to a tool-using stage, which is debatable) then it may habitually lead or trail that arm, in everyday motion, and thus be symmetric regardless.


When you get to biochemistry, that is where I feel I can be sure about the differences. There will be differences. DNA is our backbone for life (along with RNA, and plasmids and similar things), with sugar-molecules chaining to form the two strands and two pairs of complementarily-fitting nucleotides encoding the information as the 'rungs' of the many-twisted ladder.

I have no doubt at all that independently-arising life will be different. Even if the double-helix is reimplemented (and it isn't instead some other information-packing method), the strands will doubtless be composed of different biopolymeric material and the 'bases' are pretty much guaranteed to not be A-T and G-C. For efficiency's sake (might be a factor in the first battles after biogenesis when it might be easier for the proto-life molecules that don't need to synthesise and auto-cataluse a large variety of 'feedstock' molecules, in order to outcompete the proto-life that currently works with three possible 'rung-pairings', or even something that works best with triploid stranding) that seems to be the minimum necessary complexity. But should a three-stranded system arise the encoding system might also utilise the handedness of A+B+C or D+E+F molecules, in a way that A+B and C+D could not.

4. Even more generally, under different conditions (note: within a different Goldilocks Zone) the 'xeno-organic' chemistry might well be not carbon-based. Sci-fi likes to make that silicon-based, given its relative position in the periodic table and the natural alternative when looking for such a similarly-slutty bond-former. There are definitely plusses and minuses in looking towards that alternate approach to life. And if it is silicon-based, then those people looking for methane as a sign of biological activity are going to be dissapointed. They might also be looking at the wrong places (wrong temperatures and pressures) for where metalloid-based chemistry best works.

And if the speed of the chemistry (whether still carbon-based or something alternative like silicon, that can still form hyperconjugation/etc) is different because of the common components are different (logically, I suppose, with heavier atoms it should be slower) and if the exterior skin of such a being is not 'squishy', you might conceivably mistake the alien ambassador for a small rock or a strangely shaped boulder.


But even without such extremes of alternate-biology, don't go using a "DNA sequencer-onna-chip" device in order to detect life, because you'll probably not be encountering DNA (as we, and the sequencer, knows it). Indeed, if it works then I would be tempted to assume a common heritage (either panspermia upon both worlds, or life-material transferred from one world to the other in the distant past, e.g. via Martian meteorites). Which would be an interesting result.

OTOH, if it crawls/leaps/walks out of a just-landed space-capsule of non-human origin then I think you've found life, regardless of what it looks like and what any potential chemical tests might (given the opportunity) show. (Now you just need to work out what it wants, and be ready to run, attack or await a more expert communicator. I'll be just over here, behind the giant robot. Our giant robot, that is... why is there another of them? And is that the alien ambassador?)

I generally agree with what you're saying, so I'm just going to add in a few comments of my own here.

1. Which is why we should, instead of shoehorning alien life into our own planet's taxonomical classifications, come up with a system of taxonomy for each specific life-bearing planet/moon. Perhaps, then create a super-taxonomy, to classify each taxonomy based on things like chemistry, chiralty, etc.

2. You also see the basic concept of trilateralism explored in Clarke's Rendezvous with Rama.

3. Of course there's always the 4 feet, 1 arm variant. Though, I have a hard time imagining how the 1 foot, 4 arm variant would work. Would it be one large, broad appendage, working down from the main body like some water towers (or trees) here on Earth, with many toes at the bottom for locomotion? Or would the arms help in locomotion as well, much like in non-human primates? The implications for each possibility have far-reaching effects, even to things like building design and (foremost in my mind) invention of the elevator.

4. I do recall reading that silicon-based life, according to our understanding of silicon-based chemistry, would have to exist at very high temperatures. Of course, given that, the most obvious candidate to look for it would be HD 189733b

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

What springs to mind for me is some of the creatures that have been discovered in some of the depths of our own oceans, and how profoundly alien they are to us. The difference between our land-world of mammals and their world of crushing pressure and absolute darkness is only a sliver of difference compared to what we will find if we start comparing our planet to other planets.

So to answer your specifics, I think the lack of bilateral symmetry would go hand in hand with radically different biochemistry; the way we develop, and the reasons why it is "easier" to produce a symmetrical organism than an asymmetrical one, would not necessarily remain constant if the underlying molecular interactions were different.

As for eyes, we already know of plenty of life forms which have no particular need to perceive the spectrum of energy we know as visible light. I would not be at all surprised by alien life which finds such receptors similarly unnecessary, particularly since there's no reason to assume said life would be surface-dwelling.

Actually, the possibility that intrigues me the most is that of aliens that see in the radio spectrum.

[Breadknife]

Based on my background in biology, I think 1) It's almost certain that life exists on other planets, and 2) It is vanishingly unlikely that said life will resemble anything familiar to us.

I'm curious to hear your opinion of alien social evolution, because it seems to me that is also imagined as improbably humanlike. Is sentience, as we define it as humans, really likely to exist in extraterrestrial lifeforms? It seems to me that that's as unlikely as aliens having eyes and ears--hell, even more unlikely.

Let me butt in again with my own speculation...

Much as eyes (or eye-equivalents) and ears (or ear-equivalents) are going to be useful for any life that develops them in a competitive biosphere, both for predating and for avoiding being predated upon, 'socialness' seems to be a useful thing to develop. It's not just humans that are social. Meerkats, elephants, whales, many and varied 'colony' insects... socially they group (sometimes transiently, sometimes for extended periods, sometimes it's their whole life) where solo creatures expose themselves to so many disadvantages in comparison (or, shall we say, where 'society' grants the social construct, though not necessarily the individual, a great advantage).

We even see it in bacteria. Individually (or in low concentrations) you get single-cells working alone, and often just getting by by individually avoiding death by whatever means it is customarily delivered to them (predation, adverse environment, etc). In large enough concentrations (which the cells know about due to being triggered by a threshold of a certain chemical's concentration) they change their behaviour to become a slime-mold. More resistant against attack and drying out an other threats, perhaps this was the precusor to multicellularism... Freed from the need to do all things for themslves, individual cells can now even specialise as food-gatherers or distributors or enzyme extruders or the like, 'knowing' that their other needs are met, much as they are meeting the needs of their fellow cells. And then you have portugese man-o-wars, which are "colony creatures". And I'm also minded of the SF story "Specialist" by Robert Sheckley (although obviously it's fiction, so don't let me pursuade you that it's an actual example from nature. ).

...so... society (and some form of communication to glue it together, whether 'spoken' or chemical or whatever) is likely to be a good solution for life to develop (at times, and with varied degrees of permance). And when sufficiently complicated that may lead to the necessity of sentience and self-awareness (all higher animals seem to have a capability similar to empathy, i.e. "other-awareness", although the 'mirror test' has not been passed by too many creatures beyond our own species... which might mean it's not testing the right thing) in order to deal with the needs of supporting the society (lest too many individuals go their own 'loner' way and it falls apart).

Basically, any alien creature that comes and meets us is probably going to have to be an intelligent, sentient (or perhaps hive-mind equivalent), tool-using social creature of some kind, amongst various other requirements. In this manner, it would seem self-selecting that we get something that analogues ourselves in those qualities you suggest. Assuming that there isn't some even more 'alien' means of reaching similar ends.

This does not necessarily need to apply to alien species that are dominant on their own planet (similar to how we are, what with being outnumbered by the bugs and the bacteria and the viruses, of course...) but who do not develop space-travel and come to meet us (perhaps we go to meet them, or just observe them from afar, or Helliconia-like from their own orbit). However, I still suspect it'd be a likely plan-for-success for them to pursue (just like the other forms have their own successes with their own strategies). OTOH we might find that our target planet is "bugworld", where the most masterful macro-strategy has been that of sheer weight of numbers (with or without a backdrop of 'society'), or even that plantlife is truly dominant (see "Hothouse"), albeit in a (mostly) passive way.

[Britanno]

Of course they exist.

Why here's one now:

[Breadknife]

...

I generally agree with what you're saying,

Yay!

...so I'm just going to add in a few comments of my own here.

1. Which is why we should, instead of shoehorning alien life into our own planet's taxonomical classifications, come up with a system of taxonomy for each specific life-bearing planet/moon. Perhaps, then create a super-taxonomy, to classify each taxonomy based on things like chemistry, chiralty, etc.

I'm not sure about chirality, unless chemistry truly has so few answers to creating life that we need to worry about the handedness of our complex sugars, etc, as the only real difference betwen us and them.

(Although it also reminds me of a short story (Clarke? Asimov? ...not sure) where someone is transporting a vital load of helix-shaped components half-way across the galaxy, or something, that are necessary for the construction of the weapons her (I think she was a she) home needs to defend itself against a disasterous attack by some beligerant or other. There's an incident and the ship is 'spun in the fourth dimension' (something to do with the interestellar drive being used) and now she doesn't know whether she's spun a whole number of times or is a half turn out. Thus whether when she arrives, whether she and her load of vital helical-wotsits are going to be the wrong way round! I can't remember if she also pondered whether her mirrored metabolism would survive in a world dominated by wrong-way-round proteins, etc...)

I'm still minded to consider unancchored motility as one of the "super-super-kingdom" classifications to apply to (theoretical) alien biologies, although c.f. tumbleweeds and limpets for where that seemingly breaks down, already, for Earthly life.

Yes, each independant biogenesis event probably ends up spawning its own system. Although we (and the aliens) will be awfully tempted to try to classify their life (and they ours) by the system more familiar to the thinker concerned. Why I think we'll get something out of asking what they think of their own system and what they think of our own. And the matching and cross-over concepts are going to be interesting to learn about.

(2: Rama) Yes. Forgot about that. I forget if there was anything more than mere speculation about the root cause of the trifold architecture, though, as it's been a long time since I read that. (The repair spiders/etc? Were they three-patterned?)

3. Of course there's always the 4 feet, 1 arm variant. Though, I have a hard time imagining how the 1 foot, 4 arm variant would work. Would it be one large, broad appendage, working down from the main body like some water towers (or trees) here on Earth, with many toes at the bottom for locomotion? Or would the arms help in locomotion as well, much like in non-human primates? The implications for each possibility have far-reaching effects, even to things like building design and (foremost in my mind) invention of the elevator.

In the source for this idea, there were indeed 4L1A creatures (although without the underlying pentalaterilsm being known it could have easily have been interpretted as a proboscis/trunk or some sort of neck down which the eyes and mouth were somewhat migrated), and I can't remember the 1L4A forms, but I also imagine them leaping around like one-legged/four-armed versions of lemurs, along the ground, and in the trees (or tree-equivalents) swinging around like nobody's business.

I'm sure there'd be a need for more brain (or proportion of brain) dedicated to motor skills in such examples, of course...

Actually, the possibility that intrigues me the most is that of aliens that see in the radio spectrum.

Again, we think somewhat alike, it seems. Noting that there's nothing against us benefitting from the radio spectrum (something similar to pigeon/bacteria sense of magnetic fields making an internal aerial, just needs a bit of luck and reason to exist in the evolutionary roll of the dice) and, as I said, metalically-dominated 'skin' probably means external or transparent 'portal's for internal organ reception. OTOH you probably don't need to have an apature or monodirectional-aerial method of making sense of the source direction if you can 'biologically' use phased-array methods for detecting directionality.

And with metalic biologies and a presumed ability to generate, as well as receive radio waves, I could see an active sense (like bat echolocation) very much in the vein of radar reflectivity. Although that of course lights up the being concerned as he shouts out, so I suspect that passive observation (and, as a counter-measure, 'stealth' modifications to the physiology - as per pigmentation works for Earthly camoflague) would be the norm (and aiming all directional 'search beams' the more developed radar-like ability).

(This passive observation is mirrored in how our own technology has developed, as we have started to get good at finding stealthy submarines by the "quiet spot" in the sonar spectrum (especially ambient ocean noise, for those listening without themselves broadcasting) to indicate where the acoustically-dampened enemy sub might be.)


I try not to call upon them in an "Appeal To Authority" too much, and thus look for alternate illustrations where possible, but I thought I best let you know that I'm quite a fan of Jack Cohen and Ian Stewart's combined efforts regarding speculative alien biologies, physiologies and cultures, so may still be somewhat influenced by their ideas. If you're interested in these things I could point you in the direction of some of their collaborations which range from hard(-as-possible) science factual in the book entitled "What Does An Alien Look Like?" or "Evolving The Alien" (two different titles seemingly to attract different audiences, but the same book... both titles subtitled "The Science Of Extraterrestrial Life") through to actual science fiction ("Wheelers" and "Heaven"), by way of their contributing the Science chapters in the "Science Of Discworld" series, inteleaving with Pratchett's own Discworld writings. Assuming you (general you, not necessariyl Grenartia) aren't already familiar with them off of your own back, of course.

[Bottle]

Based on my background in biology, I think 1) It's almost certain that life exists on other planets, and 2) It is vanishingly unlikely that said life will resemble anything familiar to us.

I'm curious to hear your opinion of alien social evolution, because it seems to me that is also imagined as improbably humanlike. Is sentience, as we define it as humans, really likely to exist in extraterrestrial lifeforms? It seems to me that that's as unlikely as aliens having eyes and ears--hell, even more unlikely.

Our criteria for sentience is actually pretty broad, so it's pretty likely that there's alien life that meets it. However, most of our diagnostic tests would likely be useless...so we wouldn't know.

[Grenartia]

I generally agree with what you're saying,

Yay!

...so I'm just going to add in a few comments of my own here.

1. Which is why we should, instead of shoehorning alien life into our own planet's taxonomical classifications, come up with a system of taxonomy for each specific life-bearing planet/moon. Perhaps, then create a super-taxonomy, to classify each taxonomy based on things like chemistry, chiralty, etc.

1. I'm not sure about chirality, unless chemistry truly has so few answers to creating life that we need to worry about the handedness of our complex sugars, etc, as the only real difference betwen us and them.

(Although it also reminds me of a short story (Clarke? Asimov? ...not sure) where someone is transporting a vital load of helix-shaped components half-way across the galaxy, or something, that are necessary for the construction of the weapons her (I think she was a she) home needs to defend itself against a disasterous attack by some beligerant or other. There's an incident and the ship is 'spun in the fourth dimension' (something to do with the interestellar drive being used) and now she doesn't know whether she's spun a whole number of times or is a half turn out. Thus whether when she arrives, whether she and her load of vital helical-wotsits are going to be the wrong way round! I can't remember if she also pondered whether her mirrored metabolism would survive in a world dominated by wrong-way-round proteins, etc...)

2. I'm still minded to consider unancchored motility as one of the "super-super-kingdom" classifications to apply to (theoretical) alien biologies, although c.f. tumbleweeds and limpets for where that seemingly breaks down, already, for Earthly life.

3. Yes, each independant biogenesis event probably ends up spawning its own system. Although we (and the aliens) will be awfully tempted to try to classify their life (and they ours) by the system more familiar to the thinker concerned. Why I think we'll get something out of asking what they think of their own system and what they think of our own. 4. And the matching and cross-over concepts are going to be interesting to learn about.

5. (2: Rama) Yes. Forgot about that. I forget if there was anything more than mere speculation about the root cause of the trifold architecture, though, as it's been a long time since I read that. (The repair spiders/etc? Were they three-patterned?)

3. Of course there's always the 4 feet, 1 arm variant. Though, I have a hard time imagining how the 1 foot, 4 arm variant would work. Would it be one large, broad appendage, working down from the main body like some water towers (or trees) here on Earth, with many toes at the bottom for locomotion? Or would the arms help in locomotion as well, much like in non-human primates? The implications for each possibility have far-reaching effects, even to things like building design and (foremost in my mind) invention of the elevator.

6. In the source for this idea, there were indeed 4L1A creatures (although without the underlying pentalaterilsm being known it could have easily have been interpretted as a proboscis/trunk or some sort of neck down which the eyes and mouth were somewhat migrated), and 7. I can't remember the 1L4A forms, but I also imagine them leaping around like one-legged/four-armed versions of lemurs, along the ground, and in the trees (or tree-equivalents) swinging around like nobody's business.

8. I'm sure there'd be a need for more brain (or proportion of brain) dedicated to motor skills in such examples, of course...

Actually, the possibility that intrigues me the most is that of aliens that see in the radio spectrum.

9. Again, we think somewhat alike, it seems. Noting that there's nothing against us benefitting from the radio spectrum (something similar to pigeon/bacteria sense of magnetic fields making an internal aerial, just needs a bit of luck and reason to exist in the evolutionary roll of the dice) and, as I said, 10. metalically-dominated 'skin' probably means external or transparent 'portal's for internal organ reception. OTOH you probably don't need to have an apature or monodirectional-aerial method of making sense of the source direction if you can 'biologically' use phased-array methods for detecting directionality.

11. And with metalic biologies and a presumed ability to generate, as well as receive radio waves, I could see an active sense (like bat echolocation) very much in the vein of radar reflectivity. 12. Although that of course lights up the being concerned as he shouts out, so I suspect that passive observation (and, as a counter-measure, 'stealth' modifications to the physiology - as per pigmentation works for Earthly camoflague) would be the norm (and aiming all directional 'search beams' the more developed radar-like ability).

(This passive observation is mirrored in how our own technology has developed, as we have started to get good at finding stealthy submarines by the "quiet spot" in the sonar spectrum (especially ambient ocean noise, for those listening without themselves broadcasting) to indicate where the acoustically-dampened enemy sub might be.)


13. I try not to call upon them in an "Appeal To Authority" too much, and thus look for alternate illustrations where possible, but I thought I best let you know that I'm quite a fan of Jack Cohen and Ian Stewart's combined efforts regarding speculative alien biologies, physiologies and cultures, so may still be somewhat influenced by their ideas. If you're interested in these things I could point you in the direction of some of their collaborations which range from hard(-as-possible) science factual in the book entitled "What Does An Alien Look Like?" or "Evolving The Alien" (two different titles seemingly to attract different audiences, but the same book... both titles subtitled "The Science Of Extraterrestrial Life") through to actual science fiction ("Wheelers" and "Heaven"), by way of their contributing the Science chapters in the "Science Of Discworld" series, inteleaving with Pratchett's own Discworld writings. Assuming you (general you, not necessariyl Grenartia) aren't already familiar with them off of your own back, of course.

1. I don't see how that enters the equation. It just seems like a neater way to organize the various known systems of life on each planet. I.E., simply saying that planets 1, 4, 36, 78, and 285 have right-handed life, while planets 5, 6, 908, and 10432 have left-handed life.

2. Well, its because of that tumbleweed example that I'm opposed to motility-based classification.

3. Well, I was going to say for planets without intelligent life, or with intelligent life that haven't yet gotten around to taxonomy. For those with independent taxonomy, we'd probably use their systems.

4. Crossover concepts would be good. That is what science is based on, after all. The sharing of knowledge.

5. Yeah, the robospiders were trilaterally symmetric. The Ramans do everything in threes.

6. I was personally thinking of some sort of arm with an unrestricted ball joint (or multiple ball joints), perhaps with multiple eyes around some structure near the hand analogue.

7. The main problem with 1L4A with hopping/leaping/jumping as a form of locomotion is that its inherently unstable, and more likely to cause injury.

8. Or perhaps a decentralized semi-autonomous nerve cluster dedicated to motor control (kind of like how paleontologists once thought Stegosauri had two brains).

9. Indeed.

10. So long as you have metallic skin, I don't see much of a reason it itself can't act as a receiver.

11. I was thinking the exact same thing.

12. Of course, that could lead to pack and herd mentalities in predators and prey, repestively. One 'sentry' to use active radar, with some members of the pack/herd to protect it, and (I've heard this as a solution to counteract current stealth technology), several 'listeners' to spot any reflected radar signals that get redirected from bouncing back to the 'sentry'.

13. I'm not familiar with them, actually.

[Sociobiology]

An interesting speculation...

How unfamiliar? Not fitting our existing cladistic "orders" would hardly surprise me, but nothing like our "kingdoms" would. What else... Lack of bilateralism? Biochemistry we don't initially recognize as living?

I guess I'd also be surprised by a lack of eyes we recognize. There don't seem to be too many image-forming systems we can think of, even allowing abiological ones.

What springs to mind for me is some of the creatures that have been discovered in some of the depths of our own oceans, and how profoundly alien they are to us. The difference between our land-world of mammals and their world of crushing pressure and absolute darkness is only a sliver of difference compared to what we will find if we start comparing our planet to other planets.

So to answer your specifics, I think the lack of bilateral symmetry would go hand in hand with radically different biochemistry; the way we develop, and the reasons why it is "easier" to produce a symmetrical organism than an asymmetrical one, would not necessarily remain constant if the underlying molecular interactions were different.

As for eyes, we already know of plenty of life forms which have no particular need to perceive the spectrum of energy we know as visible light. I would not be at all surprised by alien life which finds such receptors similarly unnecessary, particularly since there's no reason to assume said life would be surface-dwelling.

bilateral symmetry will pop up all over the place it has to do with direction based locomotion which requires equilateral force, you will notice the vast majority of asymmetrical organisms are immobile, it is not easier to make symmetrical animals, it requires a great deal top down embryonic control.
For similar reasons we should see front ends and back ends, it it just many times more effective to have your sense organs concentrated in the direction you are going.

Eyes will be likely but as you said not a certainty, we have more than a dozen independently evolved eyes on earth but we can have water on worlds where that water receives no sunlight, sound sensing organs are almost a certainty because sound works everywhere. of course the problem with eyes and sound is which part of the spectrum they work in may not be the same as ours. Heck this is the major hurdle with understanding whale and elephant communication and they are right here.

[Grave_n_idle]

Which is equally an argument AGAINST an 'earth 2', because it means planets that might once have been in the 'habitable zone'... will have moved out of it.

Not really. Cosmic expansion really only affects galaxy clusters, IIRC.

I was reading - a while back - about Voyager entering the fringe space of our system's perimeter, and how the transition was much more sudden than had been previously expected (it wasn't this article, but this one mentions the phenomenon) and it got me to thinking - we tend to think of our 'habitable zone' pretty much entirely in terms of distance from the sun, but our habitable zone may be much more specific than that. In fact, it pretty certainly is.

For example - there is surely going to be a minimum perimeter around our galactic centre, within which planets are just unlikely to be life-sustaining. Our position within our spiral arm probably contributes - our distance from the 'leading edge' probably effects the amount of radiation we're receiving, just as our solar system perimeter appears to be unexpectedly 'strong' as a barrier against cosmic radiation.

I envision that habitable zones probably occur as 'bubbles' rather than 'bars' of habitability on the macrocosmic scale - and I'd imagine this is probably true when you're talking about interactions between galaxies, too - not just within them.

If our density is decreasing, worlds, systems, galaxies that were in habitable zones... will move out of them (and some others might move in).

[Grenartia]

Not really. Cosmic expansion really only affects galaxy clusters, IIRC.

I was reading - a while back - about Voyager entering the fringe space of our system's perimeter, and how the transition was much more sudden than had been previously expected (it wasn't this article, but this one mentions the phenomenon) and it got me to thinking - we tend to think of our 'habitable zone' pretty much entirely in terms of distance from the sun, but our habitable zone may be much more specific than that. In fact, it pretty certainly is.

For example - there is surely going to be a minimum perimeter around our galactic centre, within which planets are just unlikely to be life-sustaining. Our position within our spiral arm probably contributes - our distance from the 'leading edge' probably effects the amount of radiation we're receiving, just as our solar system perimeter appears to be unexpectedly 'strong' as a barrier against cosmic radiation.

I envision that habitable zones probably occur as 'bubbles' rather than 'bars' of habitability on the macrocosmic scale - and I'd imagine this is probably true when you're talking about interactions between galaxies, too - not just within them.

If our density is decreasing, worlds, systems, galaxies that were in habitable zones... will move out of them (and some others might move in).

For the most part, you are correct. However, again, just because the density of the entire visible universe as a whole is decreasing, does not mean that distances between planets and stars, and stars and galaxies are changing (at least when disregarding their normal orbits). Think of it like a bunch of planes taking off from an airport. Yes, the planes (galaxies/galaxy clusters, I don't recall which) themselves are moving away from each other, but the distances between objects in each individual plane are still constant.

[Grave_n_idle]

I was reading - a while back - about Voyager entering the fringe space of our system's perimeter, and how the transition was much more sudden than had been previously expected (it wasn't this article, but this one mentions the phenomenon) and it got me to thinking - we tend to think of our 'habitable zone' pretty much entirely in terms of distance from the sun, but our habitable zone may be much more specific than that. In fact, it pretty certainly is.

For example - there is surely going to be a minimum perimeter around our galactic centre, within which planets are just unlikely to be life-sustaining. Our position within our spiral arm probably contributes - our distance from the 'leading edge' probably effects the amount of radiation we're receiving, just as our solar system perimeter appears to be unexpectedly 'strong' as a barrier against cosmic radiation.

I envision that habitable zones probably occur as 'bubbles' rather than 'bars' of habitability on the macrocosmic scale - and I'd imagine this is probably true when you're talking about interactions between galaxies, too - not just within them.

If our density is decreasing, worlds, systems, galaxies that were in habitable zones... will move out of them (and some others might move in).

For the most part, you are correct. However, again, just because the density of the entire visible universe as a whole is decreasing, does not mean that distances between planets and stars, and stars and galaxies are changing (at least when disregarding their normal orbits). Think of it like a bunch of planes taking off from an airport. Yes, the planes (galaxies/galaxy clusters, I don't recall which) themselves are moving away from each other, but the distances between objects in each individual plane are still constant.

Oh, yeah, no I get that - the point I was (perhaps clumsily) making is that even galaxies have effects on one another (and elements within one another), and it's reasonable to assume there's a galactic 'habitable zone' effect.

[Anachronous Rex]

Of course they exist.

Why here's one now:

(Image)

That's not an extraterrestrial.

It's an albino chimp in a suit.

[Breadknife]

(Thank god for the scrollable Topic Review bit below the editor, otherwise I'd lose track. My large posts, your large responses... I'm sure everyone else is thinking TL;DR;...)

1. I don't see how that enters the equation. It just seems like a neater way to organize the various known systems of life on each planet. I.E., simply saying that planets 1, 4, 36, 78, and 285 have right-handed life, while planets 5, 6, 908, and 10432 have left-handed life.

I understand now. Sorry, I was thinking of you looking at each individual planets systems and making up a new Kingdom-set (or using their existing one, if they have made one themselves), but that a super-set of Kingdoms would be "universals" that applied regardless of the fine details of the local trees.

Only can we say for sure that a given LH/RH sugar (say, as a base-line for the dominant chirality on a given planet) always maps to other chemicls being LH/RH (respectively, or always anti-respectively)? It might not work like that. Or it might. Not enough data, yet!

2. Well, its because of that tumbleweed example that I'm opposed to motility-based classification.

To be honest a tumbleweed isn't self-directing, OTOH plants as we know them do have movement, w.r.y. heliotropic behaviour, so it isn't a long stretch to imagine that an alien motile creature is still, technically, a plant. But it's Triffids all over again. (Whoops: again, not enough data yet.)

7. The main problem with 1L4A with hopping/leaping/jumping as a form of locomotion is that its inherently unstable, and more likely to cause injury.

Probably why I'm imagining Leaping Lemurs, using their 'leaping and prancing' ground movement only when not swinging between trees.

8. Or perhaps a decentralized semi-autonomous nerve cluster dedicated to motor control (kind of like how paleontologists once thought Stegosauri had two brains).

Consider the octupus, as well. Apparently 2/3rds of their nerves are in their arms, and after detatchment (forced or volountary, upon being attacked) they retain some self-autonomy and trained reflexes.

10. So long as you have metallic skin, I don't see much of a reason it itself can't act as a receiver.

My electronics isnt top-notch, but I'm fairly sure you need some sort of 'spark gap' to receive, otherwise a continuous skin is just going to equalise electric/magnetic potential across itself (Faraday Caging in the process) and neutralise the receptivity. Also if phase-arraying you need multiple 'aerial heads' separated by non-conducting material, wired into whatever 'comparitor' you have that works out the phase difference and possibly recombines (with differing time-lags) the received signals to create the full-quality signal for the source being 'aimed at'. BICBW about all that.

13. I'm not familiar with them, actually.

Well, I've done my bit for selling Jack (Cohen) and Ian (Stewart)'s works already, for the day, so I won't go on about them (Jack Cohen and Ian Stewart, that is). But rest assured that Professors Stewart (Ian) and Cohen (Jack) are not only fully qualified in their respective fields of Biology (Jack. Jack Cohen) and Mathematics (ian. Ian Stewart) but work well together (Jack with Ian and, interestingly, Ian with Jack) in various collaborative works. And they've also been made Honorary Wizards of the Unseen University (this being within the Earthly/Roundworld power of Terry Pratchett of Discworld fame).


(3,4,5,6,9,11,12: Really nothing more than general agreement and/or happy acknowledgement of the information, accordingly.)

[Breadknife]

...it got me to thinking - we tend to think of our 'habitable zone' pretty much entirely in terms of distance from the sun, but our habitable zone may be much more specific than that. In fact, it pretty certainly is. [...]

I know I've mentioned somewhere recently on a forum (this one, in this thread?) the possibility of a "Galactic Goldilocks Zone". Another thing that's not my idea, but looks like you have the same sort of one. Too close to glactic centre and allthat Cygnus X-1 thing and the radiation in amongst the mass of close-knit stars isn't good for (our kind of) life, and there's probably no stability of planets if you've got a dozen stars between an otherwise likely sun and its equivalent of our neighbouring Alpha Centauri, whizzing about like nobody's business and gravitationall ypurturbing all the debris.

Too far out and nebulae may just not have enough purturbation to recoallesce into the next generation of stars (or at least with not the right mix of matter).

Similar patterns perhaps within the core of spiral arms and definitely in the gaps between them, and obviously zones that aren't "stellar nurserys" are going to have to do with whatever stars and planets they got the last time their area was a stellar nursery (and deal with the slow death of the stars that are dying), at least until the next good nova stirs things up again.

And of course we're a spiral galaxy. Other types (already different ages from our own, with different suns also representing different points throughout the standard stellar evolution graph, and some apparently with hyperactive cores that might make the entire span of that galaxy uninhabitable to radiation-sensitive life¹) will have their own problemaic/advantageous areas. Especially if the potential life would have been arising just about the time that the neighbouring galaxy in the cluster starts its deathly-slow 'collision' with your own, bringing in a hail of 'fast'-moving stars through one's neighbourhood. (Mostly them all missing, I presume, given how big space is, even compared to stars, but I bet it's spectacular when you get a direct collision, and even more so with a glancing hit, from the right angle... )

(But by the time we're talking about looking for life in other galaxies, I tend to go "Of course its there," (above-mentioned 'dead zones', possibly excepting), "but we'll probably never know of it, even if Humanity lasts faaaar beyond the lifetime of our own sun." The same may be true of life from the other side of the Milky Way, but at least if we compartmentalise our own galaxy into more and less likely areas to find life (as we know it!) we can get a good idea of how long we might have to wait (or, ourselves, travel, barring breakthrough shortcuts that would be a game-changed on every level) to meet the 'neighbours'.)


¹ Or inhabitable to life that demands it? That couldn't have arisen in our neck of the woods because the conditions were too quiescent?

[Wilkshire]

Can't believe there are people who voted for the "Earth is the only planet with life" option.

125 billion galaxies, each containing trillions of stars. Whatever the odds are against life, the universe has got it covered!

[Meritocratic States]

As much as I love Sci-Fi, I'll believe alien life exists when I see it... which is doubtful.

I want my blue asari, damn it.