Head Crabs

[Digamma]

So, it'll have to either A.) Eat its host, then catch and kill more food while growing, or B.) Just catch and kill things to grow.

Yeah, thats what i ment. It would start growing, perhaps into a very small, lightly or unarmoured, Gonarch. Then after that it would have to search for a new food source or a host.

 

[Flyingdebris]

i can just imagine hl3 with attack dog sized mini gonarchs

 

[Digamma]

i can just imagine hl3 with attack dog sized mini gonarchs

That would be pretty creepy with them running at you screaming like mooses

 

[Rizzo]

The zombies lying down might be evoulving into Gargantuas but your arrival at ravenholm might have interupted it? Or they where recently turned into Zombies and hadnt had a reason to get up till Gordon got there.

Did i get that right? The head crab evoulves into a Gargantua, then a Gonarchs?

 

[Sam]

Gargantua are the giant blue things from half-life 1 that you can only kill through environmental stuff or explosives.
Gonomes are the further evolved zombies.
Gonarchs are the giant armoured headcrabs with a scrotum underneath

 

[TheGMan.]

Maybe the headcrab use's special alien powers to control the body... anybody think of that one? It probably insterts microblisamslisisms into the head controlling the body... but seriously, trying to figure out how a alien controls a human body is like figuring out why peanuts don't digest, and you see it in your shit... You just won't figure it out :\

 

[Rizzo]

trying to figure out how a alien controls a human body is like figuring out why peanuts don't digest, and you see it in your shit... You just won't figure it out :\

Hahahaha.

Gargantua are the giant blue things from half-life 1 that you can only kill through environmental stuff or explosives.
Gonomes are the further evolved zombies.
Gonarchs are the giant armoured headcrabs with a scrotum underneath

But you got what i meant right? That the zombies that are "sleeping" in ravenholm, are evolving. Well Im just guesing.

 

[Digamma]

actually i think they are sleeping to conserve energy. since everyone is zomies, there is nothing to eat. so they are just waithing for someone...

 

[Talyn]

A thought or two...

I always figured that the headcrabs are native to Xen, just like the bullsquids, houndeyes, barnacles and (?)Vortigaunts. Now, we've seen both bullsquids and Vortigaunts eat headcrabs - this implies to me that the small, quick, ominivorous headcrabs are very near the bottom of the food-chain.

First, let us discuss the generic headcrab. Now, if I was a small, more-or-less helpless organism in an extremely hostile environment like Xen, how would I survive? Why, by finding something big and strong to defend me, of course! Headcrabs attack humanoid things en masse, accepting as many losses as necessary to get a couple of humanoid hosts. These hosts then quickly mutate - humans grow the super-dense muscle tissue and elongated toughened claws we have come to associate with "headcrab zombies."

I imagine that headcrabs originally evolved to have Vortigaunts as hosts - and a Vortigaunt headcrab zombie would be pretty cool, though probably identical to a human one for gameplay purposes, b/c with no connection to the Vortessence, no lightning - because they have their brains in a relatively easy-to-access place, a small head. These new Vortigaunt hosts now serve as protection for the other headcrabs in their clutch.

My original thought was that the hermaphroditic headcrabs actually planted eggs in the host (like viruses, or certain species of arachnid), and the host body was mutated to be an effective guardian of the eggs, but I'd forgotten about the Gonarch, which really does seem to be a headcrab "queen." I think that there are two possible options (both of which have probably already been presented here, though I can't recall the specifics). The first is that Gonarchs are a special sub-species of headcrab, like queen ants or bees, and are hatched from Mama-gonarchs and then protected by the brood until they become old enough (and armor-plated enough) to survive in the hostile Xenian environment.

The second option is that Gonarch is the final stage in the headcrab life-cycle... that is to say, a headcrab that does not find a host, but manages to find enough food and survives for a long time actually mutates into a Gonarch. Now, "teenage" Gonarchs are going to be relatively small and weak, so they either have to go after smaller prey or be protected by the mutated hosts of its clutch-mates until it reaches maturity. Either way, its not surprising that very, very few headcrabs make it to full Gonarch status.

(PS - hi! I'm new. Talyn, pleased to meetcha.)

 

[Eejit]

Welcome to the forums Talyn Good to see a new face who can write legible and intelligent posts.

A few small points though Talyn, Vortigaunts are not native the Xen, they fled there from their homeworld which was attacked by the Combine.

I believe Valve have also said that the majority of life on Xen is non-native, coming from other worlds and dimensions.

The fact that there are some wide similarities between Vortigaunts and Headcrabs is what makes me think that the Headcrabs were from Vortigaunts' homeworld and went to Xen at the same time. Backed up by the fact that Vorts can and do eat headcrab.

btw I'm not sure Vortessence is necessarily related to the lightning.

 

[XANA]

im too lazy to check, but i have a question. how come headcrabs are adapt to zombifying humans, eh? what i mean is, why are headcrabs able to zombify humans and not vortigaunts. i really dont think humans were on Xen when the headcrab came about. yes, vortigaunts are like humans in many ways, but not the head structure. and plus, maybe the mutation of the torso's exposure has to do with the involuntary reaction of the headcrab's host. if headcrabs do have a venom, maybe it injects it into the host. the venom circulates throughout the host's body and causes extreme abdominal pains. as many humans do when they have pains in their stomach area, they put their hands on their stomach. the victim's fingers would then grow sharp and long and cause the torso to open. after all, the zombie's fingers are curved all the time.
mutation is possible on the human body. the white tailed spider (Lampona murina; North Island Australia) causes necrotizing arachnadism, a problem that causes necrotic ulcers to occur and even KILL the skin. another example is the giant asian hornet (Vespa mandarinia; Asia). their venom is potent enough to dissolve skin tissue. one medical record shows that a man was stung so many times in the face, medics couldn't tell who he was!:O
sorry for the biology lesson. sometimes i cant help myself ... well anyway, ive got my point across. if someone wants pictures of the hornet, just send me a private message or something. and please dont hurt me or get mad at me;(

 

[Jintor]

It's probably just a side-effect. Certain parasites... well, as parasites, are supposed to live off their hosts, but end up killing them. Although the relevancy of what I just said is probably null, but that's what you get while I'm watching anime and browsing the boards.

 

[XANA]

well i guess your kind of right. parasites depend on the host to be alive. when you kill a zombie, the headcrab has no idea that its host is dead. it just stays on there until it dies. other than that, what i think also occurs is that the headcrab's venom affects the persons blood. i noticed this in Ravenholm (suprise, suprise) when i shot a zombie a few times, and the blood was yellow.:O but my theory is proven irrelevant. you shoot a zombie with the shotgun, blood will fling out and land on a wall or the ground, yet it comes out red. or... maybe its just the engines limited capabilities. i dont know. actually, go to wikipedia and look up headcrab, and it should have plenty of info on headcrabs. oh, and i think the headcrab uses its beaks to pierce the skull, causing the host to bleed, and cover the head while it gorges itself on blood. just a theory.

 

[Digamma]

Maybe zombies have both headcrab blood and human blood mixed together. source is very advanced. i doubt that would be something it wasnt able to do.

 

[XANA]

nah! headcrab blood is yellow; human blood is red. put it all together and what does that spell? orange!!! no seriously... it would be orange. but animals in the real world are capable of having strange effects on our blood. one species of snake has venom that, when mixed with blood, causes the blood to turn into a gelatin like substance. really deadly. headcrab venom on the other hand... well i dont know. although the black headcrabs prolly get others onto a human host in a different manner. i theorize (ive been using theory, theories, and theorize a lot lately) that when a black headcrab latches onto a host, the parasite releases a pheremone into the air because of the venom. this is possible for the giant Japanese hornet (Vespa crabro flavofasciata). this little terror can spray a chemical from its abdomen. when the venom comes into contact with the eyes, it produces not only severe pain, but a scent undetectable to humans, yet detectable to the hornets. this chemical signal tells other hornets to help attack the intruder. they are terrible little buggers i tell ya! anyone want some photos of hornets i mentioned? just say something, m'k?

 

[Darkside55]

im too lazy to check, but i have a question. how come headcrabs are adapt to zombifying humans, eh? what i mean is, why are headcrabs able to zombify humans and not vortigaunts.

Who says they're not? We simply haven't seen it. Vortigaunts are probably a headcrab's natural host. About headcrab blood and human blood, the headcrab slowly changes the human's blood to something that the headcrab is more used to; i.e., Xenian blood, like a vortigaunt. Also, headcrabs don't drink blood. They're not vampires.

Headcrabs on their own eat plants and small animals like birds. That's where they get the nutrients to grow up.

To evolve to a gonarch, they must keep doing that for a very long time and slowly become (essentially) a gigantic, armoured fastcrab.
As we know, gonarchs are rather good at killing, so they'd keep bulking up on food until they grow the eggsac and end up in the final stage where they churn out babies.

However the headcrabs evolved to do the zombification thing, I'm willing to bet that they use the zombie powers defensively, turning into gonomes to kill most stuff that would threaten the smaller crabs.

Unlikely. There are a couple of things wrong with this theory. Namely, it seems a long, drawn-out process for a regular headcrab to eat normally in order to become a gonarch. There's no reason for a headcrab to evolve (as a species) to zombify their prey in order to eat, but also make it so the only possible way they can breed more is to remain defenseless and feed on massive amounts of smaller creatures, like birds on Earth or chumtoads on Xen. We don't even know if there's a way that the headcrab, on its own, can digest food. In addition to that, headcrabs natural instinct is to couple with a host; if your theory were correct, that means that either there was no acceptable host for a headcrab, or that certain headcrabs in every litter are "programmed" to become a gonarch. The first is literally impossible because first of all, if there are zombies protecting the budding gonarch, this means there are hosts around. Secondly, again, there's no reason why headcrabs would evolve this way. If a group of headcrabs ever clustered into an area with abundant hosts, they would have NO WAY to reproduce, effectively damning themselves. The second problem is that if there is a genetic switch in certain headcrabs that, when flipped on, makes them conform to this behavior...what if said headcrab dies? Again, the cluster is doomed. It doesn't make sense to evolve like this, and for a species that is both resourceful and adapts as rapidly as a headcrab does (mutations in the species within ten years), this would have been something that'd have been corrected in their species a long time ago. And your theory is really close to being a "hive structure" theory, which I can't get behind.

On Digamma's hibernation theory, I can see where you got the idea (something like a butterfly's chrysalis). While Llama's right that it is a bit impractical, devouring the host for nutrients while it hardens itself isn't that bad an idea. It could work...if only the headcrab didn't evolve a host so damned quickly. In stage one, they've already hardened their attacking appendages (arms and claws). There's definately a period of downtime between mutations, but it's not likely to be so long as to call it a hibernation. At most I'd say it'd be a week; at the least, a day for whatever form a zombie's in --> gonarch.

And welcome to the forums, Talyn.

 

[Eejit]

Hmm XANA I always thought headcrabs must use some kind of T-DNA (or some similar mechanism) in order to cause the mutations.

 

[XANA]

no, im not saying youre wrong, but its possible for poisons to contain mutagens. if i can permission (and a photo) from a moderator (or more than one), i can post a few pics of brown recluse bites, but the pics are EXTREMELY GRAPHIC. so if any moderators are reading this, send me a private message with your answer. if you need to know what the photos look like, i can (possibly) send you a message with the photos attached. remember, if you get queezy around graphic photos, dont look... its purty ugly:x :x :x

 

[Hullu]

This may be a stupid question, but what's the deal with poison headcrabs? They don't kill, even though they take all your health! Apparently, if some other adorable creature at that moment happened to take a munch on you, you would die...but what's the point with the poison headcrabs in places where there are no other aliens around? You can just leave them alone and keep going, although you'd have to be careful not to bump into other aliens before your health is back.

 

[Jintor]

It wasn't natural evolution, it was engineered combine evolution that created poison headcrabs. At least that's my opinion. Thinking about it it probably makes sense from a evolutionist standpoint as well, because you don't want to kill the victem, you want his head so you can wander around with it. Assuming headcrabs zombify naturally...

 

[Hullu]

Hmm. The reason why I ask this is that a long time ago, I read a review of Half life 2. The reviewer noted that he freaked out everytime he heard the voice of poison headcrabs, and he said he really panicked when they were around. But I don't see why, since most of the time they are alone, hence harmless. Even in Ravenholm it's quite easy to get rid of other aliens while the headcrabs are poisoning you. They just seem so useless, and i don't understand why anyone would panic because of them?

 

[Sam]

The thing about poison headcrabs is that while you get distracted by another headcrab, you can get jumped on by one and then finished off by a normal / fast crab. Well, in theory - it never happens

I think the poison headcrabs also do a slight amount of normal damage too, but can never get you below 1hp on their own.

 

[ríomhaire]

This may be a stupid question, but what's the deal with poison headcrabs? They don't kill, even though they take all your health! Apparently, if some other adorable creature at that moment happened to take a munch on you, you would die...but what's the point with the poison headcrabs in places where there are no other aliens around? You can just leave them alone and keep going, although you'd have to be careful not to bump into other aliens before your health is back.

From a gameplay standpoint none. From the Combines view black crabs will kill humans and make zombies.

It wasn't natural evolution, it was engineered combine evolution that created poison headcrabs. At least that's my opinion. Thinking about it it probably makes sense from a evolutionist standpoint as well, because you don't want to kill the victem, you want his head so you can wander around with it. Assuming headcrabs zombify naturally...

Marc has stated that they're from Xen as are the antlions.

 

[Eejit]

no, im not saying youre wrong, but its possible for poisons to contain mutagens. if i can permission (and a photo) from a moderator (or more than one), i can post a few pics of brown recluse bites, but the pics are EXTREMELY GRAPHIC. so if any moderators are reading this, send me a private message with your answer. if you need to know what the photos look like, i can (possibly) send you a message with the photos attached. remember, if you get queezy around graphic photos, dont look... its purty ugly:x :x :x

True, poisons can contain mutagens. But the fact that zombification produces the "maw" for ingestion, and the clawed hands suggests to me that it would be something more specific than that.
That's why I go for the T-DNA explanation anyway.

 

[XANA]

god! no matter how many times people try to counter my theories, ill just keep em coming. this is no exeption. ok, everybody knows that headcrabs have two or four beaks, right? well maybe one beak has a chemical thats like an anti-coagulant, another contains chemicals that speed up blood production, another that keeps the host alive, and the final one sucks up contents. a bit like the assassin bug. its beak is made up by two needle like structures. one containing a toxin that liquifies the inside, and the other acts like a vaccuum (sp?) to suck up the insides. man im SUCH a geek!:dork: and im proud!

 

[AJ Rimmer]

god! no matter how many times people try to counter my theories, ill just keep em coming. this is no exeption. ok, everybody knows that headcrabs have two or four beaks, right? well maybe one beak has a chemical thats like an anti-coagulant, another contains chemicals that speed up blood production, another that keeps the host alive, and the final one sucks up contents. a bit like the assassin bug. its beak is made up by two needle like structures. one containing a toxin that liquifies the inside, and the other acts like a vaccuum (sp?) to suck up the insides. man im SUCH a geek!:dork: and im proud!

How the hell can you remember all that? I have problems remembering what Chlorofyll does.

 

[XANA]

its easy... just keep reading about it over and over and over and over and over and over. and keep doing that for about 1-2 hours straight. ive been studying the living world ever since i was about 8 or 9 years old, so i have experience about that kinda stuff. you have a question, post me a message, and i MIGHT have the answer.

 

[Eejit]

Ok, show me an example of a toxin which can produce new organs in an infected host which can then be used to the advantage of the parasite please.

 

[Jintor]

Marc has stated that they're from Xen as are the antlions.

I know they're from Xen, I was just hypothesising (oooh, big word!) as to whether or not they zombified other species besides humans or if that was a side-effect.

 

[XANA]

Ok, show me an example of a toxin which can produce new organs in an infected host which can then be used to the advantage of the parasite please.

first of all, no toxin exists to create organs. plus, why would parasites even need a toxin that would produce new organs if the host is fine. take the parasitic relationship of the small braconid wasp and the tomato hornworm. all the wasp does is lay her eggs inside the caterpillar using an egg laying tube (ovipositor). after some time, the larvae will develop cocoons visible on the caterpillar's back. after that, the young wasps hatch and devour the caterpillar from the inside. simple as that... i think. in conclusion, parasitic animals and insects dont need an organ producing toxin because their host matches the parasite's needs already. did i win

 

[Eejit]

No, my point was that headcrabs do mutate their hosts creating an organ (the feeding maw area) therefore toxins are unlikely to be the main cause of mutation as you seemed to be suggesting.

I did realise that toxins do not create organs, I was trying to make a point.


Of course it's all academic as the very idea of a non-terrestrial organism being able to successfully parasitise a human is ludicrous.

 

[lastHOPE_lambda]

well you know there is a parasite that lives in the ocean that can take over a crabs body, after that it high jacks the sex organs and finds another parsite infected crab to reproduce. of coarse they don't grow any new organs and the crab does die after the parasites done with it but it shows the some organisms are able to control others. As for the mutations that the headcrab causes I agree with the tRNA thing. oh and also I'd like to add scientist are already using small devices to controll an insects mind and its been quit sucessfull. They are even thinking of using mind controlled bugs as spys.

 

[Eejit]

Oh it wasn't a typo when I said TDNA btw, it's one of the main methods used for creating transgenic strains of plants. Though I suppose maybe tRNA could work too (too tired atm to check).

Still, all these examples of what Earth parasites do to each other still doesn't make it any less ridiculous that a complete alien with no common evolutionary history is supposed to be able to be a far more effective parasite at first contact with the human race. Even if an alien species with parasitic tendencies ever came to Earth I don't think it could ever evolve to parasitise a terrestrial species as efficiently as headcrabs do, since they would be biologically so dissimilar.

 

[Darkside55]

Marc has stated that they're from Xen as are the antlions.

No, Marc has left us with a vague quote that could be interpreted either that poison crabs were naturally-occuring evolutions from Xen, or that normal headcrabs ate something poisonous on Earth and adopted the attribute, much like certain species of frogs, reptiles, and insects on Earth do. We discussed this already, remember?

Still, all these examples of what Earth parasites do to each other still doesn't make it any less ridiculous that a complete alien with no common evolutionary history is supposed to be able to be a far more effective parasite at first contact with the human race.

They're just that good. But sci-fi parasites are like that; upon first contact they adapt quickly to their new hosts. The Zerg come to mind (being the perfect parasitic organism, changing their hosts like headcrabs [but to a much more exaggerated degree]), and to a lesser extent those parasites from The Faculty that took control of human bodies, but didn't mutate them.

 

[lastHOPE_lambda]

Oh it wasn't a typo when I said TDNA btw, it's one of the main methods used for creating transgenic strains of plants. Though I suppose maybe tRNA could work too (too tired atm to check).

Still, all these examples of what Earth parasites do to each other still doesn't make it any less ridiculous that a complete alien with no common evolutionary history is supposed to be able to be a far more effective parasite at first contact with the human race. Even if an alien species with parasitic tendencies ever came to Earth I don't think it could ever evolve to parasitise a terrestrial species as efficiently as headcrabs do, since they would be biologically so dissimilar.

Stranger things have happened.

 

[Talyn]

Still, all these examples of what Earth parasites do to each other still doesn't make it any less ridiculous that a complete alien with no common evolutionary history is supposed to be able to be a far more effective parasite at first contact with the human race. Even if an alien species with parasitic tendencies ever came to Earth I don't think it could ever evolve to parasitise a terrestrial species as efficiently as headcrabs do, since they would be biologically so dissimilar.

Well, as I postulated before, the headcrabs probably evolved with their typical "prey" being a humanoid something with an obvious head... and, especially in science fiction, creatures can become endlessly inventive in their will to survive. Really, being able to parisitically mutate hosts into protective hulks does sound like the sort of thing that could apply to different species, so long as they have some kind of head that controls the thought processes and central nervous system.

 

[Jintor]

But, once more: Where are the zombie vortigaunts?

 

[Talyn]

Sounds like a much-needed mod, to me. Or maybe a foe for Aftermath! That would be very cool.

 

[Darkside55]

But, once more: Where are the zombie vortigaunts?

Vortigaunts probably have all kinds of counter-measures from headcrabs. First of all, unlike human beings, the slaves are never without weaponry to fend off headcrabs. Slow and ponderous as they are, if they didn't sneak up on a vortigaunt, the slave could pick them off easily from a distance. And I'd imagine that, in case a headcrab ever did manage to land on a vortigaunt, the vortigaunt could discharge itself with a burst of electricity, killing the crab before serious damage occurred. Their whole bodies are probably conductive, not just their hands.

 

[ríomhaire]

But, once more: Where are the zombie vortigaunts?

Somewhere we weren't.