Entomological look at the Zerg

[VoodooWasp]

Been a while since I posted here but feels good to be back with a new thread

This will be a rather long post but I assure you it's worth reading!

First of all let me explain some terms that will be used throughout the analysis.
Entomology is the science of insects even though it often covers other arthropods as well (and ironically the biggest dinosaur we know of was discovered by an entomologist).
Arthropods are all invertebrates that have an exoskeleton, segmented body and jointed legs, examples include insects, crustaceans, arachnids, myriapods etc.

What I want to accomplish with this analysis is to show how similar the Zerg are to arthropods despite being a mixture of very different organisms most of which are vertebrates. I strongly believe that the Zerg are predominantly an insectoid alien race that shares many features with Earth's arthropods.
Blizzard themselves have stated in the original game's manual that the original Zerg were insectoids resembling maggots, further more they have pointed out deep see organisms as a major inspiration for SC 2's Zerg.

Now let us begin!

At first glance the Zerg share many things with arthropods especially insects. They are called the swarm and their main structure a hive all names associated with insects but what if we take a closer look?

One of the things that define arthropods like insects is the exoskeleton, some might think that vertebrates also have exoskeletons, with turtles being a popular example, however they do not have a true exoskeleton since their carapace is simply an extension of their endoskeleton. A real exoskeleton serves as support for the body as well as an attachment point for the muscles not just for protection as in turtles and some other vertebrates.
Do the Zerg have a true exoskeleton then? It's hard to say, what's sure is that they possess an endoskeleton with most units having a defined spine and ribs. But let us look at the unit that is closest to the original Zerg, the larva! The unit is said to have a segmented body, decentralised nervous system, multifaceted eyes and many small segmented legs. Clearly the larva is very insectile when it comes to it's morphology so we can assume that the first Zerg were indeed very close to being true arthropods.
Most Zerg units have an exoskeleton as well as an endoskeleton but before we jump to the conclusion that this sets them apart from arthropods we need to consider one thing, something that very few people actually know, the fact that most arthropods have endoskeletal features as well. In insects the endoskeleton is made up from ingrowths of the exoskeleton, which of course means that it's not a true endoskeleton, but in most other arthropods like spiders and crustaceans there are actual endoskeletal features that are in no way connected to the exoskeleton, they serve as points for muscle attachments and support for internal organs. So we can safely say that the possession of an endoskeleton is not restricted to vertebrates alone!

Many would say that exoskeletons put a serious limit on body size, it is something that I see being used to justify the need for adding endoskeletons to big insectoid creatures in fiction, however this might not be so true. First of all exoskeletons, at least in insects, don't grow thicker with size, in fact they grow isometrically meaning that the new muscle mass that is attained with growth would always be enough to support it, also insect exoskeleton is rather light yet strong this is achieved by using sclerotin to make it strong without making it heavy, it's no coincidence that most insects are excellent fliers. The major limiting factor for size when it comes to arthropods actually comes from molting. Molting is the shedding of the old exoskeleton and the hardening of the new one, during that period the new skeleton is soft and can't support a large body, this is where an endoskeleton's role comes in, it would support the soft new body until it hardens enough. The other problem is that the thicker the exoskeleton the longer it'll take to harden, for example the largest terrestrial arthropod alive today is the coconut crab which takes at least 3 months to fully harden it's exoskeleton after a molt. An animal as big as an Ultralisk would take way too long to harden it's skeleton, yet we mustn't forget that the Zerg are alien so they surely have a different chemistry and might possess proteins that harden the exoskeleton faster than Earth's arthropods.
One problem to having both skeletal structures aside from the weight and metabolical demand is the lack of space for muscles. This is the major problem I have with Blizzard's design for most Zerg units. One needs not look further than the Defiler to see this problem, it has long thin appendages much like insects yet from SC 2 we know that it also has bones which would leave almost no space for muscles and would hinder it enormously. A proper way to handle a dual sleletal system can be seen in the Tyranids from the Warhammer 40,000 universe, they have skulls and a spine but their appendages are only exoskeletal which gives them a better leverage for the muscles as well as enough space.

Arthropods have an open circulatory system, how about the Zerg? We can't be sure about this but from what we can see they must have a closed one judging by their activity and size, an open circulatory system would be a problem for large animals. Yet even with this there is an exception. Some crustaceans have a circulatory system that is neither open nor closed, being called partially closed by some biologists. I am sure that Blizzard weren't aware of this when designing the Zerg but mentioning that deep sea organisms were a major inspiration can't be more fitting!

Few know this but the Queen started of as a literal giant insect, an old concept art by Samwise show how the original idea for the Queen was a creature that looks strikingly similar to parasitoid wasps which is a logical decision considering how the Queen is supposed to inject eggs with the help of her ovipositor. Here is the said concept art compared to a parasitoid wasps ovipositing in an unfortunate aphid:

Also what started off as a very reptilian/amphibian creature evolved into a very insectoid one in the case of SC 2's Zergling design which added insect wings possessing venation quite similar to dragonflies.

Another thing that most people don't know is that the concept of an animal using viruses to alter another organism's body is far from being a fictional thing. Parasitoid wasps have been known to have assimilated a virus millions of years ago and use it to infect their host and later it's body functions. The host can even be manipulated to guard the wasps eggs after they violently burst out of it's body. I highly recomend watching this video if you want to know more: Body Invaders

Assimilating foreign genes into their own is also quite real, in fact a microscopic animal called rotifer uses this ability very well which helps it reproduce without intercourse. As a matter of fact even we acquire some genes through the consumption of organic substances.

I hope you enjoyed this entomological look at the Zerg and be sure to comment and share your thoughts!

[Eligor]

Been a while since I posted here but feels good to be back with a new thread

This will be a rather long post but I assure you it's worth reading!

First of all let me explain some terms that will be used throughout the analysis.
Entomology is the science of insects even though it often covers other arthropods as well (and ironically the biggest dinosaur we know of was discovered by an entomologist).
Arthropods are all invertebrates that have an exoskeleton, segmented body and jointed legs, examples include insects, crustaceans, arachnids, myriapods etc.

What I want to accomplish with this analysis is to show how similar the Zerg are to arthropods despite being a mixture of very different organisms most of which are vertebrates. I strongly believe that the Zerg are predominantly an insectoid alien race that shares many features with Earth's arthropods.
Blizzard themselves have stated in the original game's manual that the original Zerg were insectoids resembling maggots, further more they have pointed out deep see organisms as a major inspiration for SC 2's Zerg.

Now let us begin!

At first glance the Zerg share many things with arthropods especially insects. They are called the swarm and their main structure a hive all names associated with insects but what if we take a closer look?

One of the things that define arthropods like insects is the exoskeleton, some might think that vertebrates also have exoskeletons, with turtles being a popular example, however they do not have a true exoskeleton since their carapace is simply an extension of their endoskeleton. A real exoskeleton serves as support for the body as well as an attachment point for the muscles not just for protection as in turtles and some other vertebrates.
Do the Zerg have a true exoskeleton then? It's hard to say, what's sure is that they possess an endoskeleton with most units having a defined spine and ribs. But let us look at the unit that is closest to the original Zerg, the larva! The unit is said to have a segmented body, decentralised nervous system, multifaceted eyes and many small segmented legs. Clearly the larva is very insectile when it comes to it's morphology so we can assume that the first Zerg were indeed very close to being true arthropods.
Most Zerg units have an exoskeleton as well as an endoskeleton but before we jump to the conclusion that this sets them apart from arthropods we need to consider one thing, something that very few people actually know, the fact that most arthropods have endoskeletal features as well. In insects the endoskeleton is made up from ingrowths of the exoskeleton, which of course means that it's not a true endoskeleton, but in most other arthropods like spiders and crustaceans there are actual endoskeletal features that are in no way connected to the exoskeleton, they serve as points for muscle attachments and support for internal organs. So we can safely say that the possession of an endoskeleton is not restricted to vertebrates alone!

Many would say that exoskeletons put a serious limit on body size, it is something that I see being used to justify the need for adding endoskeletons to big insectoid creatures in fiction, however this might not be so true. First of all exoskeletons, at least in insects, don't grow thicker with size, in fact they grow isometrically meaning that the new muscle mass that is attained with growth would always be enough to support it, also insect exoskeleton is rather light yet strong this is achieved by using sclerotonin to make it strong without making it heavy, it's no coincidence that most insects are excellent fliers. The major limiting factor for size when it comes to arthropods actually comes from molting. Molting is the shedding of the old exoskeleton and the hardening of the new one, during that period the new skeleton is soft and can't support a large body, this is where an endoskeleton's role comes in, it would support the soft new body until it hardens enough. The other problem is that the thicker the exoskeleton the longer it'll take to harden, for example the largest terrestrial arthropod alive today is the coconut crab which takes at least 3 months to fully harden it's exoskeleton after a molt. An animal as big as an Ultralisk would take way too long to harden it's skeleton, yet we mustn't forget that the Zerg are alien so they surely have a different chemistry and might possess proteins that harden the exoskeleton faster than Earth's arthropods.
One problem to having both skeletal structures aside from the weight and metabolical demand is the lack of space for muscles. This is the major problem I have with Blizzard's design for most Zerg units. One needs not look further than the Defiler to see this problem, it has long thin appendages much like insects yet from SC 2 we know that it also has bones which would leave almost no space for muscles and would hinder it enormously. A proper way to handle a dual sleletal system can be seen in the Tyranids from the Warhammer 40,000 universe, they have skulls and a spine but their appendages are only exoskeletal which gives them a better leverage for the muscles as well as enough space.

I like the thought that giant arthropods are a bit more scientifically plausible than usually claimed. I think that in terms of muscle mass we can refer to ants that are very strong compared to their size. Could something similar apply to the Zerg?

The Zerg are not just insectoid but really a mishmash of every possible kind of invertebrate though (there's a lot of crustacean and mollusk and trilobite to them), plus an addition of some vertebrate/sauroid features that are largely cosmetic (but increasingly less so towards SC II, as the art gets more comic-booky/cartoony).

Re: Inspirations from nature.

The Zerglings were clearly suggested by Raptors from Jurassic Park, they are the most inconsistently portrayed unit by the way with the Zerglings in original SC cinematics ("Wasteland Patrol" and "Brood War Intro") looking way more spindly and insectoid than in the concept art (Samwise's drawing in the original manual looks more like a WarHammer squig) and with a large chitinous crest similar to the one posessed by Hydralisks (and the teeth are not true teeth embedded in gums but simply sharp protrusions of chitinous mandibles, much as with hydralisks). By SC II the Zergling again becomes closer to the cartoony squig like concept art, gets gums, loses crest, becomes more sauroid and gains a couple of stubby mandibles/horns by the side of the mouth and (of course) insect wings.

Hydralisks owe a good deal to slugs, mantids and snakes. Do they leave a trail of mucus behind? Some depictions show that they do, the sprites in the original StarCraft show their tail/"foot" muscle to possess small segmented legs like those of a scolopendra to help them locomote, however those are absent in cinematic art (but reappear again in a much more atrophied form in SC II)).

Overlords are basically flying lobsters, the original queen was a flying cuttlefish with tusks (very Lovecraftian in a way), Guardians are flying crabs (but became more ray inspired in SC II losing much of their arthropod features).

Mutalisks are basically dragonflies with bat wings. And as the original manual states, the concept doesn't look terribly aerodynamic.

Devourers are beetles with chitinous protective wings (elytra) over functional ones used for flying (now there's an anatomical feature that doesn't get featured enough in creature design).

Ultralisks also have a vaguely beetle shaped body and their blades were originally oversized mandibles (much like in certain stag beetles and ant-lion larvae).

The Defiler by the way is pretty much a Eurypterid (giant prehistoric sea scorpion) without much alteration. So the picture below is a scientific reconstruction, not game concept art, they didn't even enlarge it much as the largest sea scorpions known reach 2.5 metres in length.




There are not many insects that look terribly "Zergy" by the way, the only ones that come to mind are exotic mantids, scolopaendra and ant lion larvae.
Here are some pictures of naturally occurring "Zerginess".

Mantids (Idolomantis and Paratoxodera)




A portrait of a scolopendra


Ant lion larva (the adult ant-lion by the way is a delicate and harmless looking dragonfly like thing that wouldn't look out of place in a Disney movie)


Horseshoe crabs would also make a great basis for an armoured Zerg unit (they basically look like alien biological war machines).

[Turalyon]

Some really cool stuff here. Wish I could comment on this stuff more, but I fear my ignorance limits me here.

Not sure what to make of the Zerg having amphibian/reptillian origins though. Sure, they are just billed as "insectoid" (not really insects) and that it's just a conceit of them being fictional aliens, but it seems odd that something could evolve from being a vertebrate to an invertebrate. Doesn't feel right somehow.

Many would say that exoskeletons put a serious limit on body size, it is something that I see being used to justify the need for adding endoskeletons to big insectoid creatures in fiction, however this might not be so true. First of all exoskeletons, at least in insects, don't grow thicker with size, in fact they grow isometrically meaning that the new muscle mass that is attained with growth would always be enough to support it, also insect exoskeleton is rather light yet strong this is achieved by using sclerotonin to make it strong without making it heavy, it's no coincidence that most insects are excellent fliers.

I would think that the issue regarding exoskeletons limiting body size would be more due to a matter of physics. The density of a large exoskeleton would be many times that of a small exoskeleton (especially if it's supposedly hard enough to mitigate damage from gunfire) and though the larger exoskeleton may have more muscle to compensate, the scaling of strength and weight are not equal when it comes to size (proportional strength). It's such that if the proportions were the same but just sized up, the larger body would need way more muscle to move that body than what the exoskeleton could conceivably contain. That's not even mentioning the extra weight of that extra muscle that needs to be moved, either!

[VoodooWasp]

I like the thought that giant arthropods are a bit more scientifically plausible than usually claimed. I think that in terms of muscle mass we can refer to ants that are very strong compared to their size. Could something similar apply to the Zerg?

The Zerg are not just insectoid but really a mishmash of every possible kind of invertebrate though (there's a lot of crustacean and mollusk and trilobite to them), plus an addition of some vertebrate/sauroid features that are largely cosmetic (but increasingly less so towards SC II, as the art gets more comic-booky/cartoony).

Re: Inspirations from nature.

The Zerglings were clearly suggested by Raptors from Jurassic Park, they are the most inconsistently portrayed unit by the way with the Zerglings in original SC cinematics ("Wasteland Patrol" and "Brood War Intro") looking way more spindly and insectoid than in the concept art (Samwise's drawing in the original manual looks more like a WarHammer squig) and with a large chitinous crest similar to the one posessed by Hydralisks (and the teeth are not true teeth embedded in gums but simply sharp protrusions of chitinous mandibles, much as with hydralisks). By SC II the Zergling again becomes closer to the cartoony squig like concept art, gets gums, loses crest, becomes more sauroid and gains a couple of stubby mandibles/horns by the side of the mouth and (of course) insect wings.

Hydralisks owe a good deal to slugs, mantids and snakes. Do they leave a trail of mucus behind? Some depictions show that they do, the sprites in the original StarCraft show their tail/"foot" muscle to possess small segmented legs like those of a scolopendra to help them locomote, however those are absent in cinematic art (but reappear again in a much more atrophied form in SC II)).

Overlords are basically flying lobsters, the original queen was a flying cuttlefish with tusks (very Lovecraftian in a way), Guardians are flying crabs (but became more ray inspired in SC II losing much of their arthropod features).

Mutalisks are basically dragonflies with bat wings. And as the original manual states, the concept doesn't look terribly aerodynamic.

Devourers are beetles with chitinous protective wings (elytra) over functional ones used for flying (now there's an anatomical feature that doesn't get featured enough in creature design).

Ultralisks also have a vaguely beetle shaped body and their blades were originally oversized mandibles (much like in certain stag beetles and ant-lion larvae).

The Defiler by the way is pretty much a Eurypterid (giant prehistoric sea scorpion) without much alteration. So the picture below is a scientific reconstruction, not game concept art, they didn't even enlarge it much as the largest sea scorpions known reach 2.5 metres in length.




There are not many insects that look terribly "Zergy" by the way, the only ones that come to mind are exotic mantids, scolopaendra and ant lion larvae.
Here are some pictures of naturally occurring "Zerginess".

Exoskeletons provide more area for muscles to attach to and also better leverage, so an animal with an exoskeleton will always be stronger than an animal of the same size with an endo one.

The original icon from SC for the carapace upgrade is a turtle shell () though which makes me think that Blizzard imagined the Zerg to be more reptilian than insectoid despite what's stated in the manual.

Hydralisks are largely serpentine, the spines along the lower body doesn't seem to be feet though just spikes that help with movement or maybe even defence.

Early Ultralisk concept makes them look very reptilian because they have scales.



Most insects are very symetrical, smooth and beatiful unlike the Zerg which are intended to look fleshy and even a bit disgusting

Some really cool stuff here. Wish I could comment on this stuff more, but I fear my ignorance limits me here.

Not sure what to make of the Zerg having amphibian/reptillian origins though. Sure, they are just billed as "insectoid" (not really insects) and that it's just a conceit of them being fictional aliens, but it seems odd that something could evolve from being a vertebrate to an invertebrate. Doesn't feel right somehow.



I would think that the issue regarding exoskeletons limiting body size would be more due to a matter of physics. The density of a large exoskeleton would be many times that of a small exoskeleton (especially if it's supposedly hard enough to mitigate damage from gunfire) and though the larger exoskeleton may have more muscle to compensate, the scaling of strength and weight are not equal when it comes to size (proportional strength). It's such that if the proportions were the same but just sized up, the larger body would need way more muscle to move that body than what the exoskeleton could conceivably contain. That's not even mentioning the extra weight of that extra muscle that needs to be moved, either!

I never stated that they had a vertebrate origin, in fact I stated the opposite The original Zerg were maggot-like insectoid parasites, the only reason the primals look so beast-like is because they are actually the result of the parasitic Zerg merging with it's host which happens to be a vertebrate.


The strongest exoskeleton on nature is that of the ironclad beetle, entomologists use drills to make holes in them for a pin and some have even reported some surviving being run over a car, not bad for a critter that is only a few cm long! The thing with insect exoskeleton is that it's very light unlike other arthropods' that use minerals to strengthen it. It's not a coincidence that insects were the first animals to develop flight, they are light and yet tough.
Also an exoskeleton limb is actually stronger than one of the same size with a bone. If you want to know more you should read this

The only thing that limits an animal with an exoskeleton from growing large is the molting process, one way to overcome that is to have an exoskeleton that grows with the body which is what I think the Zerg have.

[Jconant]

The thing to also bear in mind is evolution is open season on diversity. Even if the first zerg were at first insect like, one of the key traits of zerg is the ability to manipulate its own dna (or mutagen or w/e alternative method of molecular blueprint they use) and steal anothers' to use as their own. A zerg doesn't need to go through the millions of generations to go through speciation, so it makes sense for zerg to possess both endo and exoskeleton; it is making the most out of both.

[VoodooWasp]

The problem with having both skeletal structures is that, at least, in the limbs, there will be no free space left for the muscles! However there is a way around that, we just need to take a look at the Tyranids, they have a skull and a spine while everything else is exoskeletal! That leaves enough space for the muscles in the limbs to use the better leverage provided by the exoskeleton as well as more points for attachments for the muscles while the skull and spine protect the most important parts of the body
From what I've seen about the Zerg they seem to have a full endoskeleton (example the Defiler skeletons we need to recover in one of the missions) which would hinder them more than help...

[Visions of Khas]

From what I've seen about the Zerg they seem to have a full endoskeleton (example the Defiler skeletons we need to recover in one of the missions) which would hinder them more than help...

Well, the term exoskeleton implies a load bearing system, which I do not believe the Zerg have. If you examine the Hydralisk model from the cinematics, you see a system of overlapping protective plates, not a support system. The zerg have less of an exoskeleton and more a carapace or hardened dermal layer. It may be composed of some organic polymer, making it lightweight.

[VoodooWasp]

Well, the term exoskeleton implies a load bearing system, which I do not believe the Zerg have. If you examine the Hydralisk model from the cinematics, you see a system of overlapping protective plates, not a support system. The zerg have less of an exoskeleton and more a carapace or hardened dermal layer. It may be composed of some organic polymer, making it lightweight.

True, this is why turtles don't have an actual exoskeleton since it provides no support aside from protection. However in the game you can read that the term exoskeleton is used for the Hydralisk and Ultralisk so perhaps they do have one

[Visions of Khas]

However in the game you can read that the term exoskeleton is used for the Hydralisk and Ultralisk so perhaps they do have one

They may provide some kinda of support for some musculature, but I don't think it's the primary musculo-support system. It probably supplements the internal skeleton, likely providing an anchor point for antagonizing action.

Assimilating foreign genes into their own is also quite real, in fact a microscopic animal called rotifer uses this ability very well which helps it reproduce without intercourse. As a matter of fact even we acquire some genes through the consumption of organic substances.

The green sea slug is a striking example of horizontal gene transfer. At some point in the past, likely by viral vector, the genes of some algae were assimilated into the sea slug's genome. As a result, these sea slugs can photosynthesize using chlorophyll. It's pretty wild.

[Jconant]

@voodoowasp: notice how some of the limbs of say, the roach operate just that way. Its upper limbs with the giant jabbing claws are all muscular protruding out from openings/ weakspots of the roach's shell (seem to be skeletal), while its walking limbs have carapaces. Oddly enough all the limbs of the zerg are segmented like instects, yet have musculature like vertebrates.