The Only Sci-Fi Explanation of Hominid Aliens that Makes Scientific Sense

By Kyle Munkittrick | July 12, 2011 8:45 am

Science fiction has a problem: everyone looks the same. I know there are a few series that have aliens that look unimaginably different from human beings. But those are the exception, not the rule. Most major sci-fi series – Star Wars, Babylon 5, Mass Effect, Star Trek, Farscape, Stargate – have alien species that are hominid.

Consider the above image. Of the twenty visible species, only five are visibly not hominid. That’s right, I count the prawn, xenomorph, predator, Cthulhu and A.L.F. as being hominid. I grant that it’s a bit of a stretch. A more conservative evaluation would be that only two of the twenty are truly hominid. The others, which we’ll call pseudo-hominids, still share the following with humans: bipedal locomotion; bilateral symmetry; a morphology of head, trunk, two arms, and two legs; upright posture; and forward-facing, stereoscopic eyes. I grant they don’t look precisely human, but the similarities are too striking to be swept into the nearest black hole.

Even the most strident supporter of parallel evolution would laugh in the face of anyone who claimed that the most intelligent species on nearly every planet in the universe just happened to evolve the exact same physiology. In series like Star Trek and Mass Effect, where interspecies relationships are possible, this cross-species compatibility is made even more preposterous. We all suspend our scientific disbelief to enjoy the story and the characters. No one believes for a second that the first species we meet in the cosmos is going to look just like us save for some pointy ears and a bowl haircut.

But what if many species in the universe do look like humans? How in Carl Sagan’s cosmos could we explain parallel evolution of that magnitude? Star Trek: The Next Generation, manages to give a scientifically plausible answer to the question of hominid and biologically compatible alien species in an episode entitled “The Chase.” Which lead me to develop the Hominid Panspermia Theory of Science Fiction Aliens.

My guess is that the writers of ST:TNG didn’t intend to plug a genre-spanning plot hole in “The Chase” given that it is, on its own, a pretty goofy episode. But, intentional or not, they gave me enough fuel to come up with a theory that would explain away a lot of sci-fi alien species similarity without resorting to a “that’s just how it is” answer. That said, I’m going to ignore the plot and jump right to the meaty conclusion. At the end of a string of clues, the crew of the Enterprise, along with a begrudging team of Klingons, Cardassians, and Romulans, activate a message from a past species. Star Trek lore is mixed as to what the nature of this species actually is, so I’m going to leverage some creative license and summarize it as I see fit. In short, an ancient hominid species sends a message to all future hominid species. That message is as follows:

Intelligent life evolved in the universe – once. The First Intelligent Species became spacefaring but, unlike the adventures depicted in most science fiction, they found an uninhabited universe. Non-intelligent species were too rudimentary or too far away to be detected. Thus, as both a memorial to themselves and to enliven the universe, the First Intelligent Species seeded the necessary DNA for the eventual evolution of intelligent life in the primordial oceans of every planet that could support life. The First Intelligent Species did not only design the DNA to evolve intelligently, but to parallel their own evolution. An application of the idea that “ontogeny recapitulates phylogeny” on the scale of life itself. Our corner of the universe thereby became the home of Vulcans, Romulans, Cardassians, Humans, Betazoids, and other hominid species which are all decedents of the First Intelligent Species. Therefore, in the eyes of the universe, the many hominid species are closely related despite their disparate home planets.

The Hominid Panspermia Theory, as I call it, explains a lot. Why are most hominid species variations only cosmetic and cultural? Because their genetics are designed to prevent significant deviation from the First Intelligent Species’ mold. How can species interbreed? They share a distant ancestor the way lions and tigers do. How are there so many species at nearly the same level of technological development? Life was seeded on many planets at approximately the same time. These nagging, infuriating questions that take me out of the story can be set aside because I have a plausible scientific explanation. The Hominid Panspermia Theory also titillates my need to believe we are neither the only nor the first intelligent species in the universe.

The Hominid Panspermia Theory also helps explain how there are so many bizarre life-forms throughout the universe without invoking near-deity races like the Q. One could argue that in the time that it took the seeded planets to evolve spacefaring hominid species, many other forms of life, intelligent and otherwise, evolved as well. The result is a near-universe that is largely populated by hominid alien species and a far-universe populated by inconceivably strange alien species. Furthermore, unintentional forward-contamination from the First Intelligent Species would have allowed unguided panspermia to trigger life in unexpected and unanticipated ways. Thus, many alien first contacts with Humanity were with hominid aliens. As exploration continued outward from the seeded galaxies, stranger and more truly alien species were encountered.

Finally, the Hominid Panspermia Theory still requires abiogenesis at some point and allows for multiple occurrences. That is, human beings could theoretically be the First Intelligent Species. Or among some of the only life in the universe. You don’t have to presume humanity is the product of some previous species to believe the Hominid Panspermia Theory is a scientific possibility, nor does Hominid Panspermia Theory fall prey to the “well who seeded the seeders?” reductio.

I apply the Hominid Panspermia Theory theory to pretty much every sci-fi series I encounter that involves multiple alien species that are hominid. For series in which the species are distinctly hominid but not mammalian, such as Mass Effect, I just modify the theory so that the First Intelligent Species was arbitrarily dumping seed genetic code into every splash of primordial soup they could find with no intent to reproduce themselves and/or that their explorations recklessly forward-contaminated the universe. Life with a very similar genetic base still gets scattered about, but less planning leads to much less parallel evolution.

Thanks to the Hominid Panspermia Theory of Science Fiction Aliens, my neurotic need to explain the similarity among spacefaring species is sated and I can go back to enjoying the photon blasts and spaceship explosions.

Bonus Points: Can anyone name all the aliens in the picture? I only managed fourteen out of twenty.

Follow Kyle on his personal blog, Pop Bioethics, and on facebook and twitter.

Image of diverse aliens via alien species wiki. Image of ancient hominid via memory alpha.

CATEGORIZED UNDER: Aliens, Biology, Philosophy, Utter Nerd

Comments (66)

  1. notovny

    In using species from Wayne Douglas Barlowe’s “Expedition”, I’d have gone for the Eosapien ( ) instead of the Emperor Sea Strider (upper left corner in the image, ) . The Eosapiens are presented as sapient and tool-using, as well as being nonpedal, whereas the Emperor Sea Striders don’t have any of those traits.

  2. J.S.Lopes

    We could call Hominid Panspermia Theory as Creative Laziness Theory, because some Sci-Fi authors don’t want to waste more time and brainstorming to imagine weird non-humanoids; or Low-Budget Theory, because 60’s TV series like Star Trekk didn’t have money enough nor convincent visual effects . So… let’s fill Universe with humanoids.
    In Marvel comics, a similar explanation – based on Erick von Daniken’s Astronaut Gods theory – is an old race of powerful and gigantic beings, The Celestials, who travelled the Universe interfering on the evolution of rational beings. They came to Earth, picked a bunch of apelike hominids and turned them into the matrix of humans.

  3. Amy Guskin

    If your qualifications for pseudo hominids are “bipedal locomotion; bilateral symmetry; a morphology of head, trunk, two arms, and two legs; upright posture; and forward-facing, stereoscopic eyes,” you can’t lump Babylon 5 in with those other series. Babylon 5 prominently featured two alien races throughout most of its five seasons that were not hominid or pseudo-hominid: the Vorlons and the Shadows. The Vorlons were beings of energy, represented mostly by one ambassador who visited the station inside a non-hominid encounter suit. And the Shadows were insectile, with the sentient representatives of the species having six legs, and several pairs of eyes that angled off to each side of the head.

  4. vel

    Of course, this also assumes that DNA wont’ be the only way to have life. Perhaps it is? And, perhaps, the hominid form is the most efficient. One can postulate giant intelligent amoebas, creatures of “pure energy”, various water based intelligences, world sized winged tenacled things, but they all have some major problems with how they would interact with the world as we humans do and seem to do well.

  5. J.S.Lopes

    A pivotal point is: are DNA or RNA universal, or are there another species of possible nucleic acids? In Earth DNA/RNA are based on five nucleobases and phosphoric acid; should we expect to find diverse nucleobases and acids?

  6. I think this:

    “The Hominid Panspermia Theory also helps explain how there are so many bizarre life-forms throughout the universe without invoking near-deity races like the Q. One could argue that in the time that it took the seeded planets to evolve spacefaring hominid species, many other forms of life, intelligent and otherwise, evolved as well. The result is a near-universe that is largely populated by hominid alien species and a far-universe populated by inconceivably strange alien species.”

    makes the most sense, and is certainly the most interesting possible result of the theory.

    This is a fun read, and I think it makes a lot of sense. Sure, there are some loop-holes, but I think you’ve put more thought into this than most and it’s not overtly fiction-y. I bet you could make a book on this ‘theory’; it’d probably do well amongst the normal crowd.

  7. Jim

    #1 – I don’t think it’s necessarily fair to call that laziness. If someone’s making a TV show and they have a limited budget and finite time to come up with the next episode, they’re subject to different practical constraints than an author writing a book. And even a writer has to conserve their readers’ attention; if it isn’t the sort of story where more ‘realistic’ aliens would help the plot, then adding them might not be worth the extra effort on the author’s part to describe them, or on the readers’ part to understand them.

  8. Chris Winter

    J. S. Lopes asks: Should we expect to find, on other worlds, diverse nucleotide bases for life-forms?

    I say, with backing from J. B. S. Haldane, that we shouldn’t expect not to find such diversity.

  9. John

    Some exceptions: The Horta from the original Star Trek was silicone-based, and looked more like a rock than a hominid…David Brin’s “Uplift” novels introduce a number of non-homonid types…Vernon Vinge proposed dog- or fox-like creatures that shared intelligence among pack mates, growing brighter or dimmer as their numbers changed..Robert Forward suggested manta-like forms that inhabited the atmosphere of Saturn…granted these are all easier to write about than portray visually on video, but there’s no reason to suspect our form is the most likely to evolve.

  10. Cathy

    I used a variation on this sort of explanation in a book I wrote.

  11. Chris Winter

    First, some quibbles: You probably should have led off with “Science fiction on television and in movies” instead of just “Science fiction.” In SF literature, of course, there are no limitations on the nature of the aliens portrayed. (Two good examples are Hospital Station by James White and Watchers of the Dark by Lloyd Biggle.)

    Television and movies (at least so far) have the limitation that human actors must portray their aliens. Even so, they manage to do some impressive work with prosthetics and CGI. Think: Jabba the Hut. Perhaps the most creative television show in this respect is Doctor Who.

    The Humanoid Panspermia Theory arose quite early in Star Trek with an episode called “For the World Is Hollow and I Have Touched the Sky” in which Kirk & crew encounter a hollowed-out asteroid containing a humanoid society that has forgotten its origins. The asteroid was one of many created and set in motion long ago by “The Fabrini,” a superior civilization that wished to preserve some remnant of itself. Due to equipment malfunctions, it is now on collision course with an inhabited world.

    Needless to say, Kirk and Spock set things to rights. Spock even copies from the Fabrini data banks a cure for the incurable disease “polycythemia” contracted by Dr. Mccoy. (I guess they couldn’t very well call it “polyscifithemia.”) 😉

    Personally, I’ve gotten more forgiving over the years of goofs in SF plots. You’re right: the HPT helps that along. But I draw the line at blatant anti-science.

  12. jen

    Amy – 2 non-hominid species out of all of them, much like FarScape. Theory still explains why such an imbalance.

  13. CrisA

    Stargate handwaved it by the fact that most of the aliens weren’t actually aliens. Almost everyone on the other planets actually were humans, taken from Earth a long time ago by the Go’auld, who were intelligent parasitic worms that required hosts.

  14. Daniel Greer

    As a thought experiment I like the direction you took here. It does cover some of the more glaring loopholes in the traditional sci-fi approach to why there is such a dearth of variety. I do still have a few gripes with the theory overall. One is simple statistics. The probability of multiple species evolving in parallel with one another and ending up with such nearly identical morphology is literally astronomical. The diversity of environments that these creatures would have evolved in would dictate diversity in form. Even had they started out with a roughly similar set of genes, in very short order those genes would have created massive differences in form. Any proof you might need of this theory exists right here on Earth. As far as we know, every species on Earth evolved out of a common set of genes. From Great Blue whales to plankton and ants to elephants. This has all occurred in the last 1-1.5 billion years. Not all that long in the grand scheme of things. So if we got such an enormous level of diversity here in that span, I think it reasonable that such diversity would occur elsewhere in a similar time frame.

    This leads to the next set of problems. Unless we presume that the First Intelligent species had faster-than-light travel, the sheer distance involved makes Hominid Panspermia impossible. Even if the first planet they seeded was in their own solar system, the time it would take to get to the second planet would have left the first planet to run amok for whatever that time span was. So unless they left an attendant population on every single planet they seeded, the DNA would have begun evolving in unplanned and unanticipated ways. So, unlikely that they would have evolved into a bipedal, bi-laterally symmetrical form. Our own planet provides clues to this as well. Look at how uncommon non-avian bipedal creatures are here on Earth. Even our closest cousins here still use all four limbs for locomotion. The reason I suggest excluding avian species is that they were a fluke of survival from an event that throws a substantial statistical curve into the mix. Those survivors represented only a very narrow range of species types.

    The last problem I have is that we are assuming that life has to begin in a set of circumstances nearly identical to our own. I have never encountered any compelling evidence that would prove that life can only originate in these circumstances. The works of David Brin provide some fantastic food for thought along these lines. Anything from a Jovian type world, to a star. The plain fact of the matter is that we are trying judge the contents of an entire universe by looking through a keyhole.

  15. Tristan

    Mass Effect doesn’t have star trek style hybrids you know. Asari, who could mate with anything, actually just used the DNA of the other species to randomize a few parts of their own.

    The children were always born Asari. due to this method of reproduction, they only have one gender as well, a female like form.

    At one point someone else raised an interesting point: Humans had a huge range of genetic diversity, something the other races seemingly lacked. there were all very homogenous in terms of looks and genetics, something that, IIRC, attracted the collectors to humanity, as well as made us desirable to the Asari.

    Actually crossbreeding of races was said to be impossible, with a Quarian female even going so far as to say the very nature of cross species fluid transfer could be a problem.

  16. Paul

    Looking like humans? How about just being around with us humans? Other species should have reached intelligence billions of years sooner or later. Most of the aliens we encounter will either be unicellular or godlike.

  17. Dave

    If we ever make contact with other sentient species in the universe, we might indeed find that they are somewhat hominid-looking, and for a reason that has nothing to do with spacefaring races or panspermia.

    When it comes to sentient species we have a sample size of one: ourselves. The genus homo is the only unambiguously sentient line the Earth has ever seen, as far as we know. And a sample size of one is not enough to generalize anything, especially about how sentience evolves.

    Once we have learned much more about evolution and sentience, we *may* find that a hominid-like shape (even if the species evolved from bugs or jellyfish) is actually a REQUIREMENT for sentience. Or not. The point is, we don’t KNOW yet. The self-appointed SF science experts who scoff at hominid-shaped aliens simply haven’t considered all the possibilities.

    And don’t even get me STARTED on the people who laugh derisively at the notion of single-ecosystem planets…

  18. Kyle Munkittrick

    Hmm, so I’m going to clarify one item that is coming up a lot in the comments, which is the question of diversity. I’m not questioning that many, many very good science fiction stories in any medium have lots of non-hominid aliens. What I’m doing in a tongue-in-cheek kind of way is trying to explain universes that were built out of budget and creative restraints using science as if I was in that universe.

    I grant that there are many species that look non-human (i.e. the Hutts, the Shadows), but those make sense because they are so radically different from humans. It makes LESS sense that species spawned in different galaxies should look anything like us.

  19. Kyle Munkittrick

    @Daniel: Nice comment, my response:

    1. According to the “ancient hominid” in the Star Trek episode, the genes were not only seeded, but designed to cause parallel evolution. The genetic engineering wasn’t just for the organism or species, but for the entire Tree of Life for a given planet. Your argument that all life on Earth came from a single set of genes is exactly why I find hominid aliens so preposterous. It takes super gene engineering for me to even begin to accept it.

    2. Engineering the DNA in part preempts this point, but also we presume that the species was at least warp-capable. I don’t deny the cogency of this argument, just that it doesn’t apply here.

    3. In the ST:TNG, all the seeded planets were M-Class, that is, Earthlike. Again, your science is sound, but that issue is addressed.

  20. Maria

    Scientifically humans look the way we do because nature has chosen traits for intelligence, the traits you’ve mention in humanoids , bipedal and so on are traits needed to manipulate the environment, what is the use of intelligence otherwise, without an opposable thumb how can a creature manipulate something? Yes a species could have physic powers or maybe their environment is so different it doesn’t require physical manipulation but I think that would be the exception. On worlds similar to our own it make perfect sense that nature would choose the same type of traits for its intelligent life with slight differences due to the species they have evolved from.

  21. Hollander

    You know, this hominid theory is actually quite good, and might in fact be truthful in real life. In Genesis, it is written that God has made man in his own image, and there are theories today about an alien race that generated large genetic modifications in homo erectus to bring forward homo sapiens (and this also explains the missing link). An interesting theory indeed.

  22. Knute Dunrvnyet

    What about Niven’s ‘Puppeteers,’ ‘Grogs,’ ‘Tnuctipun,’ or even ‘Moties???’ [ plus ‘Jotoki’]
    ‘Thrint’ and ‘Kzin’ match the hominid thing…

  23. Carol H

    Farscape did actually have the most alien of aliens – cases in point: Pilot and Rygel – Plus as a bonus they were both main characters (when the Jim Henson Company is doing the show – aliens can be truly alien).

    Follow the links for images:

    But there were many humanoid individuals on Farscape besides the token Earthling (John Crichton) and that is a mystery that is gradually revealed throughout Season 4 and finally solved (perhaps) in PK Wars.

  24. LeiLani

    Bilateral symmetry is not limited to humanity, in case you’ve forgotten. Virtually all “higher” animals on this planet are bilaterally configured, if not bipedal. Virtually all earth-walking creatures exist as variations on a theme: four limbs and one head. (I’m excluding insects, which while not quadrilateral are certainly bilaterally symmetrical.)

    There are non-human intelligent animals on planet Earth, including whales and dolphins, dogs and cats, and any of the simians. But the ability to build complex technological apparatus like a spaceship requires the ability to refine and manipulate raw materials and the ability to communicate and to record and pass on information on a grand scale. Bipedal physical structure wouldn’t be required. Sophisticated technological capabilities WOULD require some physical means of manipulating raw materials. An efficient, broad-scale and generation-spanning form of communication would also be necessary. The lack of opposable thumbs mean whales and dolphins can’t build spaceships, though it’s certainly possible that their cousins from another world might be able to do so.

    Of course those cousins would still need some type of limbs and specialized digits to develop that technology, and the ability to use those digits without having to walk on them.

    Which brings us back to bipedalism or something close to it, in terms of biological economy. Humans could and probably would encounter other types of non-bipedal non-humanoid creatures out there, but only when we land on their turf. When it comes to fellow travelers, the balance is in the favor of bipeds or something mighty close to it.

    Or I suppose we might encounter the odd centaur on the block, but that’s another kettle of old fish.

  25. Dmitri

    I don’t know, the idea of an intelligent race “programming” DNA to re-evolve into themselves seems a little… inelegant.

    Why couldn’t it be a completely unrelated advanced species that came through here briefly (500 mya or so), and seeded life to nearby (relatively speaking) systems from a common source? Either purposefully (for whatever reason) or even as an accidental contamination.

    I’m pretty sure you can go as far back as the jawless fishes and have a pretty solid chance of evolving something vaguely hominid on an Earth-like planet. Maybe even further back than that.

    Of course the annoying part with this way of explaining it is that Earth would have to be the origin planet, since we have an evolutionary record going much further back than that.

  26. Craig

    OR perhaps the simplest explanation is the easiest. These are pretend TV shows and as such are limited by budgetary constraints. A human actor in a costume is easier than generating an entire CGI cast.
    It would also ruin most storylines as it would be improbable that any 2 species would breathe the same atmosphere.

  27. Foxxfyre

    No….nobody is gonna name the aliens? Really? I mean, I know this is more on the science side than fiction, but NOBODY?

  28. Of course the question can be reframed as “What if we are the Progenitors?” If we’re alone or eukaryotic (let alone bilaterian) life requires ridiculous timespans to happen, then do We have a moral imperative to seed the Galaxy with Life like ours (defined in a broad sense) deliberately?

    In Ursula LeGuin’s Hainish stories, the Hain spread out into the Galaxy 2 million years ago and seeded multiple planets with Hainish kinds of life – cats and dogs as well as humans – and then forgot about it all. Then, when technical civilization revived on Hain, they spread out and recontacted their lost daughter worlds. She developed the idea in the days before molecular biology made it pretty clear that chimps and humans aren’t too far apart, so in later stories which mention it, she makes characters note how the Ancients took native Earth-life and re-engineered it to be more Hainish.

    Of course if we do discover that evolution has a limited tool-kit and produces much the same life on every sufficiently alike planet, then all this discussion will seem quaint. With our limited understanding of how these things happen, I’d say that’s just as likely as the current fashionable idea that “aliens” will be utterly “alien”.

  29. Erik

    Well, at least you need at least a pair of free arms and digits in order to be able to manipulate your environment, develop technology and eventually build spaceships. A worm with the intelligence of Albert Einstein is still nothing more than a worm if he cannot build things or communicate easily with others.

    So even if you start evolution as something else, the evolutionary path for a spacefaring species eventually will lead to a basic humanoid shape, maybe a few extra arms, legs or eyes. On the other hand, if the extra arms and legs are not necessary, they might dissappear in evolution.

    You might encounter other types of species, but these will never be able to develop and build/operate spaceships if they lack digits and an opposable thumb, an easy communication method such as speech, as well as sight and hearing.

    So the humanoid shape might actually be the most efficient for species that use tools and build things, so it will be logical that other spacefaring species you encounter have roughly the same shape.

  30. There is another theory in Star Trek The Original Series about the Preservers that were “a highly-advanced alien race who passed through the galaxy rescuing primitive cultures in danger of extinction, and seeding them on other worlds were they could be allowed to grow and thrive. Their activities accounted for a great many number of the humanoid species in the galaxy.” It’s all on Memory Alpha.

  31. Cmdr. Awesome

    I’ve always hated this particular argument amongst sci fi fans. Mainly because, frankly, it misses the point, in much the same way that most people miss both the point of Asimov’s Three Laws and the beautiful forest for all those damn trees. It just comes across as nitpicking. (In this particular case, the real point is that people relate far better to humanoid aliens than to non-humanoid ones.)

    Yes, it can occasionally spark some interesting debates on the potential physical variations that life can take on. But I think a more interesting take on it is being able to view human behavior under the lens of something ostensibly alien but still very much human, and being able to make a literary correlation between a distillation of human form and a distillation of human traits and behavior.

    For instance, cartoonists have been using caricatures of the human form for decades to instill an automatic emotional response in us – Disney has this down to a science at this point. Literary works try to do something similar; many good books distill a protagonist and antagonist into “relatable” and “other”, and then examine character growth and interaction.

    Some of my favorite science fiction novels have done something else – used characters that could easily be described as humanoid, but tried to assign completely alien characteristics and motivations to some of those and used a human-centric perspective to try to examine and understand a truly alien being. (CJ Cherryh has done this a few times – the Iduvei from Hunter of Worlds, the Downers, and to a lesser extent the dudes from the series where humans crash on the moon of some planet, I don’t remember what they’re called.)

    I dunno, it’s probably just me…but I think examining Asari as a caricature of, say, human pride is more interesting area of exploration in scifi than “Asari can’t possibly exist, and here’s why!”

    (on a completely different note – anyone besides me really want to see a Mass Effect comic or short CG bit for Blasto: Sting of the Jellyfish? “Enkindle this!” gets me every time.)

  32. Chris

    When I was teaching a biochem class I had thought about this a little. First off interbreeding isn’t as easy as you are making it seem. Humans and chimps (or any other primate) are very closely related and as far as I know there aren’t any human-monkey hybrids.

    Also while I can believe over millions of years two separate planets could evolve life which used similar biochemistry processes and enzymes, that doesn’t necessarily mean the DNA will be the same. There are physical reasons why glucose is the most popular carbohydrate on the planet. beta-glucose is the lowest energy anomer. And given the efficiency of the Krebs cycle and glycolysis, it is likely another life form would take the same route. These processes need enzymes which would be very similar. Not exactly since even life forms on earth have a different amino acid here or there.

    With all the said, why would the DNA be so different? Remember the DNA is just a storage medium, it’s the proteins that do all the translating to make the DNA useful. These are the 3 base pair codons. Thin of it this way. Every time you hit a letter on the keyboard, it sends out a little sequence of pulses (the ones and zeros of binary) which the computer makes into letters on the screen. If it put out a different sequence, the computer would still work just fine assuming the software had been changed to know what the pulses meant. Now let’s say you try to create a hybrid of these two organisms even if they had the same base pairs (trying to install a PC product on a Mac, or the impossible way they so easily interface with alien computers). It wouldn’t work.

    Now of course they seeded the planets with the DNA, but over billions of years? What if the asteroid impact had occurred 70 or 60 million years ago, would we be 5 million years more advanced or still swinging in trees? Even under your idealistic scenario, I can’t see it happening. I still enjoy watching scifi though.

  33. @ Chris Winter: If you’re quoting Haldane…should we expect a lot of beetle-insectiform encounters, then?
    @Knute – Thank God; you can’t really have this discussion without Niven and he makes the same point that @Erik and@LeiLani do: if you can’t manipulate tools with flippers or hands or tentacles, you’re not an intelligent species (or, at least, not until someone who CAN finds you and figures out how to talk to you). Niven/Anderson are also occasional users of the Panspermia theory (the Protector, etc.) and occasionally not (many of the Draco’s Tavern species). I’ve always wondered about “energy” creatures – based off of Einstein’s musing that the highest form of evolution would be nothing but energy? How does a cold plasma coalesce into a consciousness?

  34. J.S.Lopes

    If hominids have not evolved to beget “intelligent” Homo sapiens, what another kinds of animals (apes excluded) could be able to fill this gap?
    1. Sea Otters have nice grabbing and manipulating skills.
    2. Racoons?
    3. Dolphins and whales are hypothetically very smart, but don’t have oppsable thumbs, nor even hands. Could create an exotic civilization with higher marks in Philosophy, Mathematics, Linguistics, Natural History?
    4.Elephants with more developed trunks?

  35. BCL1

    But if they didn’t look like us, how could Captain Kirk hook up with their females?

  36. Miles McCullough

    I’m trying to think of scenarios where non-bilateral species could develop spacefaring technology. The energy being thing is hard to see developing evolutionarily. Maybe some previous species developed technology to the point of the Singularity and built themselves superadvanced “energy bodies,” but that argument goes for any body type. I’m concerned with evolutionary bodies.

    The thing is, human evolution of abstract intelligence appears to be the collision of three fairly unique factors: high social intelligence to build on, the ability to use tools to spur abstract thought, and hunting to provide protein and further intellectual stimulation – chimps, crows, and coleoids (all bilateral) display all three behaviors implying some luck is needed as well to kickstart an evolutionary escalation of higher order thinking.

    So, assuming the evolution of large brains would be dependent on protein or some other substance that can only be derived from predation on other creatures, why couldn’t some radial ocean dwelling creatures that evolved moderate social intelligence start farming/hunting some sedentary ocean creature like clams? Perhaps if their easiest method of predation was to herd bottom-dwelling non-swimming prey into a trap they set up?

    One still wonders how advanced tools can get in an ocean environment, no matter how intelligent the species – it must be hard to experiment when substances dissolve, hides won’t cure, fire won’t work, and hard materials are scarce (no wood, brick, or metal, just secretions, shells, or bone).

    Maybe a similar sort of thing could happen in the superdense clouds of a gas giant planet? Whatever that environment produces would have to be weird, though I can’t help but imagine a world full of jellyfish and manta rays.

    Also, some good ideas above, like the centaur-type body plan with 4 legs and 2 arms, or an elephant type with 4 legs and one nose appendage for tool use. Imagine spacefaring elephants typing stuff in their keyboards with their noses.

  37. Wes

    Just for reference, the humans in Dune (the tiny guy standing in front of the big sandworm) were descended from Earth, just a few thousand years in the future. So they’re not technically “alien” : )

    The Panspermia idea was also used by the Stargate series in a very similar way that you’re using it here.



  38. Jesse M.

    The problem is that the Star Trek explanation is definitely *not* scientifically plausible, even if you grant the basic premise of our planet being seeded by advanced extraterrestrials. It requires us to believe that somehow one could “program” the detailed course of evolution in advance by putting the right genes into the initial one-celled creatures that seeded the planet, which basically seems to require a total rejection of Darwinian evolution by random mutation and natural selection! Also, if this were possible, wouldn’t we expect all lineages descending from the original seed organisms to be progressing towards a humanoid form, not just one tiny branch of the tree of descendants? Why aren’t sponges and radiates and echinoderms and molluscs evolving towards this preordained form too, do they somehow “know” that the vertebrates have got it covered already? If mammals went extinct due to an asteroid impact or something, would one of the other branches suddenly start evolving towards a humanoid form?

  39. Chris

    I have a feeling not many know the first alien in the upper left corner. That’s from “Expedition: Being an Account in Words and Artwork of the 2358 A.D. Voyage to Darwin IV”. The alien in question is the Emperor Sea Strider.

    Also the one between the Gorn and the Predator on the top line is a Drac from the 1985 film “Enemy Mine”.

  40. Jesse M.

    Yeah, on the naming the aliens question Chris just named two of the more obscure ones, I recognized all but one:

    First row: Emperor Sea Strider from “Expedition” (see ), 4th Doctor from Doctor Who, Gorn from Star Trek, Drac (named Jeriba Shigan) from Enemy Mine, Predator

    Second row: Alien from the Alien movies, ALF from the sitcom “ALF”, Vogon (Prostetnic Vogon Jeltz) from the Hitchhiker’s Guide movie, creature from “Indiana Jones and the Crystal Skull”, don’t know what that last one is

    Third row: Cthulhu from story “Call of Cthulhu”, Daleks from Doctor Who, Nakai from Stargate Universe, Thanator from Avatar, Spock from Star Trek

    Fourth row: Martians from “War of the Worlds” (see ), Morn from Star Trek: Deep Space Nine, Marvin the Martian from looney tunes, “prawn” from District 9, sand worm from Dune

  41. Sargon

    Having read the Lensman series of books, now that is a catalog of non-hominid aliens. If you’ve ever read the description of what the Velantians and Eddorians look like, nothing like them has ever been seen in sci-fi. Even though the anime Lensman tried to capture the idea of what an Eddorian might look like at the end.

    I’d just simple run with the idea that the hominid form could just be the best form to be at the top of the food chain. Animal might run faster than humans, be stronger, but when you look at most animal forms they are only good at specific tasks. The human form is much more versatile, and this form has become good at killing things. It stands to reason the hominid form is superior.

    An anime series explored this idea, Geneisis Climber Mospeda an alien race the Inbits came to earth to study evolution, the humans kept shooting at them. The Inbit start out looking like slugs, no one really gets to see them much in their natural form, but by the end the Inbits were taking on human form after experimenting with various forms. Most people will know of this as it was re-written as Robotech’s 3rd Generation. The Invid were still doing pretty much the same thing as the original Mospeda Inbits were, looking for the ultimate form. They believed the human or hominid form may have been it.

  42. jdmimic

    As someone else mentioned, Star Trek dealt with this issue (caused by low budget obviously) a few times in the original series. In addition to the Fabrini, the episode “The Paradise Syndrome” they find a relic from the Preservers, which seeded humanoid stock throughout the galaxy. Oops, I see Daniela already mentioned them. Glad I can edit my comment:)

    No bonus points for me, I can only name 15-16 (I think I know one, but can’t tell from the picture) of the aliens pictured.

  43. Josh

    With all due respect, while the author put forth a very well crafted discussion of the theory introduced by Star Trek TNG, which all of us sci-fi rans remember well, I fail to see how any of this augments the original explanation set forth in the episode, except for the fact that the author is suggesting we take that explanation and apply it to other series.

    When I read that the TNG explanation “lead [the author] to develop the Hominid Panspermia Theory of Science Fiction Aliens” I had hoped he would actually take it a step further. Is it just me, or does it seems like this was merely just a well crafted summary of the episode and its implication? I fail to see how this can be accepted as the author’s theory. That’s like tasting a big mac and saying that it inspired you to create the world’s best burger, and then putting out a product that is essentially a perfect copy of the big mac, but calling it the “Biginid Macspermia of Generic McDonalds-esque Restaurants.”

    If anything good came from this, it’s the subsequent conversation that followed. I had not read the Lensman books for example. I found Sargon’s post to be very interesting. OK that’s all for me.

    Save Stargate!

  44. Jesse M.

    Also, just a nitpick, but this article uses “hominid” as a synonym for the sci-fi term “humanoid”, but that really isn’t accurate, “hominid” refers to a specific biological clade including us along with apes (see wikipedia’s “Hominidae” article for details), even monkeys are not hominids although they are clearly more human-looking then a lot of the bipedal aliens with faces above.

    • Kyle Munkittrick

      A good point, Jesse. However, the hominid point is primarily referring to aliens that could interbreed and are biologically similar to humans, like Klingons and Betazoids. Thanks for the clarification, I’ll be more cautious with that language in the future.

  45. Alright, I’ll name the aliens…
    1. An Emperor Sea Strider
    2. Time Lord
    3. Gorn
    4. A Drac from Enemy Mine
    5. Predator
    6. …Alien
    7. ALF
    8. From The Hitchhikers Guide to to Galaxy, Jeltz the Vogon
    9. From Indiana Jones… an “interdimensional being”
    10. Blob
    11. R’lyeh
    12. From Doctor Who, a pair of Daleks
    11. Nakai from Stargate Universe
    14. From Avatar, Thanator
    15. Some guy :) kidding, Mr. Spock
    16. Martians from War of the Worlds
    17. Morn the Lurian
    18. Marvin the Martian
    19. A Prawn from District 9
    20. And a Dune Sandworm
    There! …I think.

  46. Jesse M.

    Nice work Lorena! (I posted answers earlier but it still says “your comment is awaiting moderation”, and I missed the blob) Only little thing is that you got the right story for #11, but the monster’s name is Cthulhu, R’lyeh was the name of the city where Cthulhu “waits dreaming”.

  47. Lorena Almaraz

    you’re completely right! thanks 😉

  48. Jesse M.

    Kyle, any thoughts on my earlier point that this whole idea of seed organisms that are somehow “pre-programmed” to evolve into humanoids seems totally incompatible with darwinian evolution?

  49. Geack

    @ Miles –

    “Imagine spacefaring elephants typing stuff in their keyboards with their noses…” Jerry Pournelle did exactly that – It’s called “Footfall”. Elephantine aliens invade Earth. Interesting riffs on the pros and cons of various types of locomotion and physiology.

    Also want to throw out a second or third mention of David Brin’s Uplift books for having a really convincing, well thought-out collection of ALIEN aliens – not just variations on things we see here on earth.

  50. Chris Winter

    Justin wrote (#31): “If you’re quoting Haldane…should we expect a lot of beetle-insectiform encounters, then?”

    I should have made it clear that I was referring to Haldane’s dictum — to wit: “The universe is not only queerer than we imagine; it is queerer than we can imagine.”

    But as regards finding “beetleoids” on other worlds, I wouldn’t rule it out. They have six legs, so could evolve manipulators without losing sure-footedness. Of course, the exoskeleton would be a handicap to developing the sort of high-energy metabolism they’d need. They probably would require a world like Earth in its Pennsylvanian period, when oxygen reached 35 percent and dragonflies had two-foot wingspans.

  51. Amy Guskin

    >> Amy – 2 non-hominid species out of all of them, much like FarScape. Theory still explains why such an imbalance. <<

    Jen: regarding Babylon 5, no, it's two non-hominid species out of six major species that were the focus of the show (Humans, Minbari, Narns, Centauri, Vorlons, and Shadows). If you expand out to consider the other races shown throughout the series, you’d add a couple more non-hominids, but I wasn’t talking about every alien-race-of-the-week; only the six major races that comprised the main focus of the series; the “star” races, if you will.

  52. namonaihito

    The more or less similar appearance isn’t that surprising. What is weird thought is that most alien life forms communicate practically the same way we do (often they even speak English). One would expect species using other ways of communication than sound. Changing color, smell, interpretative dance, anything…

  53. Brian Too

    More species samples in literature:

    C.J. Cherryh wrote a novel that contained an insectoid race, complete with queen, group dynamics, castes, the whole recognizable package (except intelligent, and much larger than Earth bound insects).

    One of the sci-fi greats (Clarke? Heinlein?) wrote a book that contained a closing chapter. In it he speculated about a race of aliens the size of planets. They existed on the edges of planetary systems and lived lives slowly and of great length. We would call their home the Kuiper Belt or the Oort Cloud now. Communication was by radio but radio was inherent to the species’ biology and morphology, not a tool.

    I’d estimate that the body plan of a squid or octopus would permit both advanced intelligence and advanced technology. The chromatophores in their skin also would permit advanced language skills not based, as namonaihito says, on vocalization.

    Where things turn plaid, for me, is when you give up on DNA as a body encoding tool. DNA/RNA is the foundation of life as we know it. When you move away from that altogether, I suspect that more species diversity than we can imagine is possible. Physical laws must still be obeyed of course but the universe of life is potentially vast.

  54. While TV and movie SciFi aliens are humanoid because they are actors in makeup. The best authors like Alan Dean Foster and many others created aliens who are ant like (Thranx) and nearly a metre tall, or Harry Stubs created beings that are 18 inches long and two in diameter and like to live at 700 Gs but can live at anything from one G to 1000 Gs (Mission of Gravity and sequal).

    The list goes on and on.

  55. Steven

    I also appreciated the explanation for human look-alikes provided by this TNG episode.

    Unfortunately, Kyle, the episode titled “Distant Origin” in Season Three of Star Trek Voyager completely destroyed this logic.

    In this episode a scientist from a race of reptilian saurians in the Delta Quadrant discovers that the DNA of saurians (who have a hominid shape) matches the DNA of humans at 46 separate markers. He is amazed, and realizes that humans and saurians must have a shared distant ancestor.

    Upon further investigation with the scientists aboard Voyager, it is learned that the saurians were a race of intelligently evolved dinosaurs on Earth that foresaw the meteor collision that would destroy other dinosaurs and escaped into space. The shared ancestor of humans and saurians could be traced to the evolutionary split between mammals and reptiles on Earth.

    In the same episode, the saurians trade and interact with many other humanoid races across the delta quadrant – but only the humans share the DNA markers that point to common origins – which begs the question: what sort of “DNA” do all these other humanoid species have? Obviously, nothing remotely close to humans or saurians.

    Presumably, the Voyager writers on this episode were unaware that they had just made the character B’Elanna Torres an impossible hybrid (she is supposed to be the daughter of a klingon and a human).

  56. Steven

    I have a more scientific criticism of the Hominid Panspermia Theory of Science Fiction Aliens. I know we’re talking about sci-fi here – but …

    Evolution is an undirected biological process, dependent on genetic mutation and natural selection. It is impossible to predict what evolution will produce, because every tiny change in the environment and every random mutation of the genome can enormously effect the subsequent adaptations. As Kurt Wise puts it, “if … the evolutionary tape were played again, human life would not be expected. In fact, even if it were replayed a million times or more, man would not be expected again.”

    Outside of Star Trek, the only place I’ve seen this idea of forward-planned evolution is in the pseudo-scientific writings of “Intelligent Design” creationists. They suggest that God put all the genetic machinery necessary for the evolution of man into the first primordial genome, because they cannot accept that evolution can explain all the diversity of life (despite overwhelming evidence to the contrary). This is one of the the “gaps” in which ID Creationists choose to place their God. The only difference, then, between Creationism and the Hominid Panspermia Theory is that God is replaced with an ancient alien.

  57. Thomas

    Good. Now that we’ve explained that, let’s move on to faster-than-light travel and the warp drive, which the “elder” species doubtlessly needed to seed the galaxy.

  58. Ross

    It is even entirely possible that alien nucleotides will have 2 base pairs, in which case their genetic code is written in binary, or ten base pairs for that matter. That would be pretty sweet.

    Beyond that, it should be noted that cephalization (focusing of nerves into one region, leading to development of the brain) is extremely common among animals. And it’s not out of the question to suggest that alien life may also evolve cephalization because it gives an animal an information processing advantage over its counterparts, something I imagine can be important in any environment. From there evolution points to radial or bilateral symmetry; it is uncommon for a cephalized animal to have no noticeable symmetry.

    With bilateral symmetry, the basic animal layout is a tube with feeding on one side and excretion on the other. This still leaves nature a lot of options and by no means points to alien hominins; however, I expect that if intelligent aliens are found, they are more likely to be bilateral than radially symmetric because this allows the animal to further focus sensory organs that may develop, rather than have them dispersed around the animal. For example, imagine trying to read a book with 6 eyes all pointing in different directions. It would be rather hard. Furthermore, depth perception is much greater in animals such as humans where the eyes are close together and can conjointly focus on an object.

    Whatever life we find, I suggest it will be… somewhat… morphologically similar to species we have here on earth because of similar advantages evolution will seek out.

  59. Bren

    @ #30 Chris,
    How do we know that an hominid didn’t mate with another primate producing the homo sapien missing link?

  60. The problem with your hypothesis is that it’s too short-sighted. You have not considered the idea that there may be other universes out there–actually there are billions–some as small as the head of a pin, I’ve been told, and some more complex than our universe. That’s a really difficult concept for most people to consider, given our religious teachings.

    During what I call my “active meditations” one of the beings I communicate with is a member of my soul group or “cluster” as my Guardian Angel calls it who’s having a life on a water planet in the Sirius B Star System. Here’s what I asked and his reply about hominids or humanoids:

    Antura, can you tell me what percentage of the universe is made up of humanoids?

    “Yes, certainly a good percentage Tom.”

    Is it above 35%?

    “Yes, a little higher. Forty percent would be fairly accurate Tom.”

    Were humanoids created by one society?

    “This is a little like the chicken and the egg theory Tom. When Creator created this Universe, calls went out and several humanoid societies you might say responded. Naturally from them grew the large percentage of the universe you have now you see. So to answer your question, it was not just one society but a few.”

    If you wish to read more questions and answers, visit my website and click on Articles and News where all my free weekly newsletters are posted.

  61. dave chamberlin

    Ah science fiction, another one of those contradictions in terms like jumbo shrimp, the truth, industrial parks, and military intelligence. A hat tip to the comment left by #13, “the plain fact is that we are trying to judge the contents of the universe through a keyhole.” The great physicist Enrico Fermi nailed it when he interrupted his colleagues chatting about UFO’s with the comment now known as the Fermi Paradox, he simply asked “where are they?” The earth has had life on it for four billion years, complex life for half a billion years and intelligent life for only 50,000 years. If their were life forms that could colonize other planets wouldn’t they have come here? Here is a fun thought experiment, let us us conjecture that we humans advance to the ability to either inhabit or seed with complex life one more planet every one hundred years and there after continue exponential growth at that same rate. In just three thousand years we would have reached over one billion planets. It is all just idle speculation of course, we are still stuck here on this pale blue dot with a sample size of one, but what I propose is forget about our shape and form and think about our human intelligence and ambition, Earth was a rich and verdant garden left without a gardner for billions of years. It is an argument that intelligent life that can spread would have and because it hasn’t intelligent life must be very very rare indeed. After all, where are they?

  62. Neal

    I believe the SWTC theorizes that human-like life in the Star Wars galaxy has evolved to be human-like because humans have been an evolutionary force all across the galaxy for longer than the recorded history of tens of thousands of years.

  63. Jeff

    Steven said: “The only difference, then, between Creationism and the Hominid Panspermia Theory is that God is replaced with an ancient alien.The only difference, then, between Creationism and the Hominid Panspermia Theory is that God is replaced with an ancient alien.”

    Well, here’s the thing: in the fictional universe we’re looking at, which in several noticeable ways (‘warp’ drives included) bears little resemblance to what we think we know of our own, there *are* hominids everywhere. They vastly outnumber anything else. That being the data we’re stuck with, we’d have to consider theories that fit our data. The Ancient Continent of Panspermia would be worth considering I’d imagine. Perhaps the IDers have even found a universe where their theory, forced, agenda-driven and unsupported by evidence in ours, might make some sense. That said, I’d go with Occam’s razor and eliminate it anyway, especially if in that universe it were shown that these hominids were genetically close relatives. There are simpler possible explanations than a God or gods, such as Panspermia.

    Incidentally, we’ve had artificial selection at least since the dawn of agriculture, haven’t we? How is Panspermia anything but a high-tech version of artificial selection?

    My personal favorite hypothesis is slightly different from Panspermia, in that no seeding of primordial soups was necessary, just colonists. These hominids really *are* hominids in my version, some mutated naturally as their populations became isolated (adapting to their environment and to cumulative local quirks in sexual selection). The colonizing of space was relatively recent (in geological time) and the various human colonies have had enough time to diverge quite a bit but in many cases the divergence is fairly superficial.

    I don’t think we can really rule out some innate advantage to our body plan, at least until we have a fuller understanding of *why* we have big brains. If the body plan is innately superior and big brains are advantageous enough to evolve relatively often, that would be a hypothesis, but all this being speculative it seems a bit of an… ugly universe (and ultimately our data is indeed very contrived, and the universe in question is the product of imaginations not evolution, but let’s not spoil the illusion).

    The advantage of my favorite hypothesis, the “new-Earth Panspermia” (see what I did there) is that it can fit the data (a rampant body plan in our fictional universe) to just about any hypothesis for our evolving a big brain that I can think of. If big brains are primarily the product of sexual selection–absurd, costly, ungainly and expensive (but beautiful) like peacock feathers–then we’d still only need to evolve the body plan once, so the odds wouldn’t matter much.

    Shipwreck some of these hominids in different environments as “Robinson Crusoe” species, relatively bereft of technology but with big brains intact, I’d expect to see significant variation from world to world, given time. Especially if the environment were quite different from the one that evolved the original hominids, and if there were niches in the ecosystem we could evolve into (such as in a new-ish world or after a big depopulation of indigenous species).

    so to answer the “where are they?” question: we’re already here, at least in this hypothetical universe where we have a lot of hominids to explain…

  64. Matt B.

    In the past several days I have encountered three instances of people spelling the past tense of “lead” the same as the infinitive. This is wrong; the past tense is “led”.

    Phil Farrand, in The Nitpicker’s Guide for Next Generation Trekkers, debunks the panspermia idea. His argument pretty much boils down to “How do you plant genetic seeds that naturally evolve toward a target without including the target that they’re aiming for, thereby making the evolution unnecessary?”

    SG-1 was a Star Trek that didn’t need spaceships or a biological panspermia theory, but it did need a linguistic panspermia theory. In one episode they simply asked a guy if he could understand them and waited thirty seconds for the audience to forget that he shouldn’t be able to. His people had been taken from Mongolia at least a thousand years earlier.

    Have you heard of Raelianism?

    Boy, that Voyager episode with the dinosaurs is so Earth-centric (typical for Star Trek). Why didn’t they find descendents of Vulcan’s or Qo’noS’s or Betazed’s analog of dinosaurs? Always with the Earth, these people.

  65. Larry

    “Our corner of the universe thereby became the home of Vulcans, Romulans, Cardassians, Humans, Betazoids, and other hominid species which are all decedents of the First Intelligent Species”.

    Pretty sure the word you’re looking for there is “descendant”.

    Given the overall quality of the comments, I’m surprised this slipped through.


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