Alien Xenomorph Biology Explained! (Because Science w/ Kyle Hill)

  • Published on May 18, 2017
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    The Alien franchise has shown us many forms of aliens from facehuggers to xenomorphs, but how does it all work? Kyle bursts through with an explanation in this week's Because Science!
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    • CHEMICAL A0-3959X.91 - 15:
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Comments • 3 168

  • NeoDragonCount
    NeoDragonCount 2 hours ago

    Prometheus ruined the Alien franchise for me. It was much better when Xenomorphs were simply a deadly extraterrestrial fauna that the foolish humans thought they could control.

  • Callum Morris
    Callum Morris Day ago

    *ZE GOOH*

  • Sowilo Sky
    Sowilo Sky Day ago

    drills with its but makes me giggle every time

  • Eddie Arnold
    Eddie Arnold 2 days ago

    What about the squid thing from Prometheus that the woman gives birth to

  • LukeSparow
    LukeSparow 3 days ago

    Goddamnit Promethius was so dumb.

  • bigemcginn robbert james

    Another good theory I have heard is how the goo will process the DNA of whatever it has come in contact with and change it into a perfect predator to whatever that thing is

  • Dragon Gamer 2000
    Dragon Gamer 2000 4 days ago +1

    So the movies is about a black goo.... Ok

  • Duck Sandwich
    Duck Sandwich 5 days ago


  • composerdoh
    composerdoh 5 days ago

    Great video, Science Thor. I wish you'd touched more on the implausibility of elements, or more interesting bio-chemical issues, though. Like how acid "blood" could effectively transfer nutrients within an organism, or how a kitten/small cat sized parasitic creature could feed/gestate inside John Hurt for so long without being detected by the super-advanced humans, or seemingly even his own immune system!
    I would question the plausibility of alien creatures feeding on humans, as the parasites you reference do so due to millions of years of evolving side-by-side. These wasp larvae cannot digest trees or blades of grass, or even crabs, or sharks and they actually SHARE DNA with all those things! So I can't see how realistic it is for aliens to eat humans or vice-versa, when we would presumably have FAR less genetically in common with them. But you kind-of addressed this with the "black goo" thing.

  • Sarcalogos Tortolero

    So he DID put his pp in the vagina snake

  • GOONCH 2177
    GOONCH 2177 7 days ago +1

    The hawk wasps is just a small chazador!

  • AidnbGaming
    AidnbGaming 7 days ago

    Who else heard zu goo the whole time?

  • Rathanor
    Rathanor 9 days ago

    dude you forgot to explain the general morphophysiology of a xenomorph. you only tackled it's reproductive physiology. what about it's anatomy? organ physiology?

  • Shadx27
    Shadx27 11 days ago

    Well, xenomorphs due break one rule very hard, but you have to suspend your disbelief for movies. The rule they break? Rule of conservation. (Hatcher to full size alien without eating?) They gain mass from nothing. They create chemicals (mainly acids and such) without the ingredients for it. Etc. However, still scary good times.

  • Iblis Azazil
    Iblis Azazil 13 days ago

    Who gives a shit about all this new "Alien" stuff? It surely is as elaborated and thought through as the Episode-movies of another abused Sci-Fi-Franchise...
    Too decadent. Sometimes art shows itself when something is as simple and straightforward as possible. Alien 1-3 and Star Wars 1-3 were exactly that.
    Hollywood really sucks these days. And it seems to get worse and worse, with every year...

  • matthew styles
    matthew styles 15 days ago +1

    Denim shirt really? Ok jay lenno

  • Ghengis Khan
    Ghengis Khan 15 days ago

    how do they not melt with acidic blood with a ph level of -31

  • Wesley Kitchen
    Wesley Kitchen 16 days ago

    Xenomorphs can't reproduce. The queen xenomorphs keeps making eggs I a certain spot

  • aazhie
    aazhie 18 days ago

    Makes me wonder if the hammerpedes were a dead end reproductively for the goo, or if there were tiny adorable queen 'pedes

  • Clairvoyant81
    Clairvoyant81 20 days ago

    Don't really get why the dog xeno doesn't fit in there... seems to be the exact same thing, although they could have gone further with changing the design compared to the human xenos from the first two, but other than that, that dog xenomorph works perfectly fine within the "lore".
    Off to watch your follow-up video.

  • chaz
    chaz 21 day ago

    Good luck explaining this even Ridley has no idea what aliens is anymore

  • Jason Konst
    Jason Konst 22 days ago

    Xeno means unknown and not strange

  • Федя Крюков
    Федя Крюков 22 days ago

    Wait a sec. At the beginning there was darkness... I mean, according to Promethius movie there was somekind of real xenomorph (shown on a wall picture in the Promethius) who once 'empregnanted' an engineer with a 'new life' by the facehagging process thus becoming somekind of a messiah for the engineers as they completely lost the ability to give life (e.g. reproduce) by that time. But using the xenomorph's genetic material the engineers could somehow 'seed' the worlds with their genes through the painful self-sacrifice rite shown in the movie in an attempt to recreate the 'paradise' (e.g. 'engineerhood' without mating problems) through the brute force of a natural gene-recombination by starting evolution process anew time and the time again and destroying all failed experiments. And the black goo, exactly as you told, is just a weaponised by-product of engineer's initial experiments with xenomorphic genetic material. It's all in the first draft of the script for Promethius. So xenomorphs are somekind of ancient race with a bit complex reproduction process who existed thousands of years before humans and interacted with engineers using embryo-implantation long before David who just seemed to try to make purestrand xenomorph out of the genetic hymerae the black goo created using old-fashioned selection process because he's nuts.

    RAMPRAGE! 24 days ago

    can you readress this video now that covenant has been out, since now there is more relative information

  • CC MG
    CC MG Month ago

    "Vagina snake"

  • Mink plays
    Mink plays Month ago

    xenomorphs don’t mate the queen lays all the eggs

  • ChimpGuy
    ChimpGuy Month ago

    You're so cute when you say zhagoo... xD

  • alphadad1966
    alphadad1966 Month ago

    What about the Predator Xenomorp, that busts out of the chest of the Predator that hunted the Aliens in temple in Antarctica (in Alien vs Predator)? That had the 4 mandibles (2 bifurcated?) like a Predator. That would imply that the lineage of prior hosts don't really matter, and that it's more like "Alien DNA" + Host is what drives the resulting lifeform

  • Brutally Honest
    Brutally Honest Month ago

    A facehugger is an idiotic thing biologically speaking, makes not a lot of sense.
    Even in the Cotesia Glomerata example, it is the Cotesia itself planting an egg inside another animal to get shelter and food for the larvae.
    Here they nonsensically plant another step, and spawn a living being with the function to plant the larvae.
    it poses an unnecessary element of risk in being unsuccessful in reproducing.
    but fuck it,: it's Sci-Fi XD

  • Finn P
    Finn P Month ago

    But they were their own race, they had their own ship that had clearly been wrecked on that planet for a long time. So when did they have interaction with humans to make so many eggs that were in the original xeno ship. I know WY knew about the life form but no one seemed to even believe in aliens so the fact that they had such an advanced ship and so many eggs doesn’t make sense if humans are needed to create them.

  • casey leedham
    casey leedham Month ago


  • the last knight
    the last knight Month ago

    After they wasps bursts out the caterpillar the caterpillar lives then defends them while there in there cacoons

  • Kai the great pig taimer

    I love his hair

  • Weldon Spivey
    Weldon Spivey Month ago

    That's my name. Yaaaay.

  • Z A K A R A
    Z A K A R A Month ago


  • Ramey Zamora
    Ramey Zamora Month ago

    Had to flip the pic, didn't ya? Shame on you.

  • ExceptThis
    ExceptThis Month ago

    Why did you do this? Was just about to go to sleep o.O

  • Harry Wompa
    Harry Wompa Month ago

    the xeno dog does make sense, if the facehuggers are also doing horizontal gene transfer. Then the dog xeno is a splice of human, cow, and goo, like deacon is a splice of human, goo, engineer, and so is different

  • Troy Tempest
    Troy Tempest Month ago

    800 people didn't like this? What's wrong with them!

  • Katrynna Albillar
    Katrynna Albillar Month ago

    I would very much like to see an updated version of this video after Alien Covenant came out, which explains how the Alien biology was manipulated to create the Xenomorph.

  • Feels Guy
    Feels Guy Month ago

    This guy lives in a glass box.

  • Connor Fanelli
    Connor Fanelli Month ago

    Isn't wanting to study them exactly what got all the other scientists killed?

  • Jack Bruce
    Jack Bruce Month ago

    Someone please make a compilation of Kyle saying ZE GOO

  • Christopher Hoyt
    Christopher Hoyt Month ago

    1.733 cubed equals 5.204699837. How does that make the tagline work...? Or am I doing the wrong math...?

  • Nikhil Kshirsagar
    Nikhil Kshirsagar 2 months ago +1

    did anybody notice the W on the robots fingerprints at 1:05 ?

  • Mike Santillán MX
    Mike Santillán MX 2 months ago +1

    About the Dog Alien in Alien³: humans and dogs share 84 percent of their DNA, and since the facehugger came from an egg layed by a Queen that already had human DNA, it makes sense that the xenomorph was partially humanoid and part dog. Same case with the Special Edition, where the xenomorph came from a bull (cattle share about 80% of their genes with humans).

  • Gary Maxion
    Gary Maxion 2 months ago

    I get it. "Zeh goo" is you trolling us the same as when you said Batmin and Supermin. You say them all correctly in normal conversations, but in videos, you use basic Psychology to keep our attentions. How? Psychologically, humans are creatures of habit, we dislike changes to the point of irritation or infuriation, we pay more attention to said changes, and in the cases of your videos, we humans waiting in anticipation for these changes watch the video and more than likely retain most of what is said. Touché, Kyle.

  • XScorpiiusX
    XScorpiiusX 2 months ago

    Za goo

  • Xeno-Huntress
    Xeno-Huntress 2 months ago

    I'm gonna share this with my Math and biology teacher...

    ZaGoo, love it XD

  • Shark_Lover
    Shark_Lover 2 months ago

    What was that sound ?

  • Hachikki Plays
    Hachikki Plays 2 months ago

    The more bugs shown and kyle explains the weaker i get. Now im scared of moving in bed

  • Srivihar Reddy
    Srivihar Reddy 2 months ago

    Finally understood aliens. Thank you

  • AnthonyPE11
    AnthonyPE11 2 months ago

    Didn’t the engineer gave birth to a weird squid thing which later impregnates the alien guy then into the Deacon

  • Bobby Ash
    Bobby Ash 2 months ago

    What was the original xenomorph ?

  • Bobby Ash
    Bobby Ash 2 months ago

    Xenomorph pathogens could be viruses

  • Bobby Ash
    Bobby Ash 2 months ago

    Essentially xenomorph pathogens are bacteria with a more complicated cell structure, instead of nucleic acids in cytoplasm. Maybe just as simple.

  • Bobby Ash
    Bobby Ash 2 months ago

    There is a canon reference to a wasp-like xenomorph species #aliencovenant (courtesy of david's experimentation)

  • Jude Kurz
    Jude Kurz 2 months ago

    None of this is correct

  • J H
    J H 2 months ago

    That crazy fucking droid from Prometheus is the creator of the xenomorph as we know it

  • Mohammed Jamal
    Mohammed Jamal 2 months ago

    Ze goo

  • Lucho Portuano
    Lucho Portuano 2 months ago

    Say "Zeee goo" one more time, and my head will explode.

  • Batmankoff
    Batmankoff 3 months ago

    This is NOT accurate. The addition of Alien 3, which is actually quite enjoyable, SIMPLIFIES the process. As we see with the runner in A3, the xeno takes on traits, and DNA, of it's host. The host acts as the egg to the facehugger acting as a sperm. Two xenos don't fertilize the eggs. The queen doesn't need to be fertilized, that's what the host is for.

  • MultiTomtom23
    MultiTomtom23 3 months ago

    Se goo *lol* goo rne weaver *ROFL*

  • SpartanTotalWarriorguy 7372

    The black goo affects xenomorphs aswell

  • Byron Armstrong
    Byron Armstrong 3 months ago

    I'm surprised nobody has mentioned the genesis of the term Xenomorph in the Alien Franchise. Xeno means strange, foreign... or "alien."
    The first time we hear the term "Xenomorph" in the Alien franchise is during the Colonial Marines briefing in Aliens
    Hudson: Is this going to be a standup fight, sir, or another bughunt?
    Gorman: All we know is that there is still is no contact with the colony, and that a xenomorph may be involved.
    Frost: Excuse me sir, a what?
    Gorman: A xenomorph.
    Hicks: It’s a bughunt.
    It's a generic term to mean not-from-earth-creature. All they meant, is we've lost contact with the colony and it may be an alien... maybe something native to LV-426. After all, if they have never seen a RidleyScott-Aliens-alien before, how could they have a name for it? Yet somehow pop-culture grabbed that one line and decided that this is the name for "The Alien".
    Xenomorph != RidleyScott'sAlien. I wish people would stop calling it "The Xenomorph" But then what would we call it? The Alien? That isn't any better.

  • No HI-FI No life
    No HI-FI No life 3 months ago

    What is a zip back goo? Or what the hell? I have the alien box set but have not watched Prometheus yet.

  • Mr. SkyrimDoggo
    Mr. SkyrimDoggo 3 months ago

    For i am now cursed with bad dreams

  • tob ffutsmodnar
    tob ffutsmodnar 3 months ago

    Xenomorph ethnoplanet

  • Theundeadempire
    Theundeadempire 3 months ago

    I wanna know how their blood can be acidic and if their vision in the games is possible, how they can see an outline of your heat signature through walls.

    MrSIRAWESOME98 3 months ago

    this video is making me want to go back and watch the movies lol

  • missing password
    missing password 3 months ago

    Xenon morphs average life cycle(of games) is, egg (laid by queen), to face hugger, to chest buster, then the chest buster cocoons itself, and turns into a praetorian or drone(average xeno ends at drone), if turned into praetorian then it enters another cocoon stage where it becomes either a carrier, ravenger, or queen if the situation demand it

  • Jason Austin
    Jason Austin 3 months ago

    Ze goo!

  • kratos thewarlord
    kratos thewarlord 3 months ago

    I was eating

  • Kevin Thompson
    Kevin Thompson 3 months ago

    You've made a slight error:
    1.733 *squared* equals 3.003(289)
    1.443 *cubed* equals 3.004(685)
    So Alien only had 1.443 "horror"... I could have sworn it was much more than that... 🤔
    Hate to sound like a nit-picker, but...Because Science!

  • Vickers 22
    Vickers 22 3 months ago

    What came first Xenomorph or the egg?

  • Tonni G
    Tonni G 3 months ago

    How does your hair work? 😃

  • King Rahzar
    King Rahzar 3 months ago

    I heard of a jewel wasp that first cuts off a cockroach's antennae, stings it, lays the eggs in it, then entombs the unfortunate bug as the grub eats the host from the inside out

  • WeiPhing Foo
    WeiPhing Foo 3 months ago

    In 9:34 it sounded like he is going to sneeze

  • Dylan Chester
    Dylan Chester 3 months ago

    TZEE GEU....

  • Crazy Raptor
    Crazy Raptor 3 months ago

    "And SE goo"

  • epiccthulu
    epiccthulu 3 months ago

    this makes my second fav franchise cooler

  • Geronimo -JohnMo-
    Geronimo -JohnMo- 3 months ago

    If the xenomorph we're familiar with started with the humans finding the goo, how have the Predators been hunting them for as long as they have?

  • Queen Nyra
    Queen Nyra 4 months ago

    Don't forget the Neomorph. They also were created by the black goo

  • SleezyPiranha
    SleezyPiranha 4 months ago

    This the same goo from district 9

  • ima Jerry
    ima Jerry 4 months ago

    Your can say that "life finds a way "

  • Torva Messorem
    Torva Messorem 4 months ago

    And then Covenant throws a monkey wrench in your whole theory

  • Zamolxes77
    Zamolxes77 4 months ago

    Prometheus, please don't bring that shit up, its actually a black comedy lol.

  • shelia hudsons
    shelia hudsons 4 months ago

    I love this outstanding work! Kindly publish similar to this! Thanks and cheers!

  • a human that exist
    a human that exist 4 months ago

    7:20 so.. cell rape

  • RedArmyRockstar
    RedArmyRockstar 4 months ago


  • Only the
    Only the 4 months ago +1

    EYES ?.???!!
    How they contact to the enviroment

  • Aries Storm
    Aries Storm 4 months ago

    How long does it take the embryo (deposited from a facehugger) to grow into a chestburster? And what is the average lifespan for a fully grown Xenomorph?

    BECAUSE I'M BATMAN 4 months ago +1

    Oh fuck! I can see the apocalypse already😂

  • lI_Toasty_Il
    lI_Toasty_Il 4 months ago

    Gotta love alien vaginas.

  • Lulu_the_zombie
    Lulu_the_zombie 4 months ago

    Idk how my friend like this stuff but still i watched it just for my friend because im a good friend

  • wilson chew
    wilson chew 4 months ago

    Spiderman is a Xenomorph!

  • Eric Mejegård Ös7d
    Eric Mejegård Ös7d 4 months ago

    Life finds a way...


  • C M
    C M 5 months ago

    I thought the dog alien was just affected like the worms. anything that aliens gestate in area variant of the Host.

  • A Tr
    A Tr 5 months ago +5

    The moral of this story is that wasps are assholes.

  • Travis Russill
    Travis Russill 5 months ago

    Is it just me or does Kyle Hill look and act like If Chris Evans (Captain America) and Chris Hemsworth (Thor) made a love child?