Way back when I wrote, Are Barsoomians Human I said:
 

But so far, we've been looking at this Astral Projection phenomenon as peculiar to humans. And for good reason, as we've only seen it with humans. No Thark has ever materialized on Venus.

In that essay, I was observing that human races appeared on every planet in the solar system, and even beyond the solar system, while more non-human intelligent species seemed to be confined to single planets.   Indeed, I made a big deal about the Green Men of Mars, noting that they were clearly indigenous to Mars, and that they'd failed to appear on any other world.

My basic idea was that humans had the faculty of astral teleportation.  That they could project themselves and adapt themselves to other worlds.   I speculated that perhaps, in projecting themselves to other worlds, they might even mutate into the oneman or semi-human intelligent races.   Of course, if they did mutate that radically, they'd probably lose the ability to astrally teleport.   Thus, it was fairly important to the theory that humans were everywhere, but Green Men and Va Gas were confined to their particular worlds.

It just goes to show you that if we live long enough, we'll come to regret just about everything we ever say.  Because now I have to deal with the possibility of Tharks on Venus.

Before I go too much further, I should note that there are some anomalies in species distribution.  Humans, in fact, are extremely common, being observed on the Moon, Mars, Venus, Earth and Jupiter.

Oddly, Earth and Venus appear to share a couple of other minor intelligent species.   The winged Wieroo and the Amphibian Lu of Earth's Caprona appear, or their close cousins appear, on Burroughs Venus as winged Angans and amphibious Myposans.   If we look to Otis Adelbert Kline's Venus books, he also features feathered bird people who may be related to Angans, and amphibian Valkars who may be related to Myposans and Lu.   In short, there seems to be evidence that at least two non-human species may be on two worlds.

Well, what about the Tharks?   And by the way, there's no racial name for ‘Green Man of Barsoom’ and ‘Green Man of Barsoom’ or ‘Green Man’ is too cumbersome, so I'm just going to call the race of six limbed giants: Tharks.   Anyone has a problem, take it up with John Carter.

Within Burroughs, there is no, or almost no evidence whatsoever for Tharks anywhere but Barsoom.  There's a single, very very loose and tentative exception but I find it doubtful.  I'll  discuss that towards the end.

Anyway, no other Tharks in Burroughs, which is all well and good, until we look at a few related works by Otis Adelbert Kline and Ralph Milne Farley....

Well, its my own damned fault.   Or Larry Niven's fault.   See, where the trouble starts is with writers like George Alec Effinger, Bertram Chandler, Larry Niven, Allen Moore etc., who decided it would be a fun thing to write stories in which H.G. Wells Martians meet Edgar Rice Burroughs Martians.   And along the way, one might throw in C.S. Lewis, Matthew Arnold, Otis Adelbert Kline's and even Michael Moorcock's Martians.

So this gives us Mars as a great big melting pot, Barsoom becomes the starting point for a larger metafictional shared Mars.   And to be fair, there was some justification for that.  After all, Matthew Arnold's Gulliver Jones is believed by some to have inspired the Princess of Mars.  Burroughs in turn, inspired Otis Kline's Mars.   Moorcock's Mars was a tribute to Barsoom.  C.S. Lewis refers to H.G. Wells.   In short, not only are they being connected in modern fiction, but they were all connecting in other ways.   And of course, they were all based, in one way or another, on the state of scientific knowledge and beliefs prevalent during this era.   So in fact, Mars was a shared landscape, much like the old west was a shared landscape.

So, I wrote a series of essays explaining how all of these works might be pieced together on the geography of Mars as we know it now, and how each of these works might conceivably relate to each other and this greater pulp Mars.

With me so far?   Okay, well, if Mars of the pulp era was a shared landscape, then so was Venus of the pulp era.   Which lead to a few essays tying Burroughs Venus together with Kline's and Farley's Venus, and a few other pulp examples.   And it turns out to be pretty certain that Farley's Inner World and Burroughs' Pellucidar are the same place.

And of course, Burroughs' Barsoom is in the same Universe as his Earth, Moon and Venus.  So it stands to reason that this was the same universe as Farley's Venus and Pellucidar, and Kline's Mars and Venus.

And eventually, this sort of thing has finally come around to bite me on the ass.   Why?   Because these other writers actually included intelligent, egg laying, tool using, six limbed giants in some of their stories.   Now, while each of these races is quite different from Green Men, there is enough overlap both in descriptions and conceptions, that we can make an arguable case for Tharks in Space.

Anyway, onwards.

The first and perhaps the very best candidate for Tharks in Space comes from Otis Adelbert Kline's Tam, Son of the Tiger.   I'll be honest and say I've never read it.   It was serialized in 1937, published as a book in 1962.  You can find old copies in bookstores from the internet, but they're hellishly rare and expensive.  There's no synopsis or reviews or descriptions of it on the internet.   So my knowledge is very limited.

My primary source is Richard Lupoff's Edgar Rice Burroughs: Master of Adventure.   According to Lupoff, Tam is Kline's second Tarzan clone after Jan.  This time, instead of apes, Tam is raised by a white tiger.   Tam finds himself discovering a lost underground world beneath Burma.  This isn't a Pellucidarean inner world, but rather, a gigantic cave system.   Within this cave system, presumably, Tam finds all manner of strange and wonderful creatures.

He also finds something else:   Four-armed, blue-skinned, giant warrior humanoids.   These, Kline informs us, are the inspirations or sources of the Hindu Gods.   Lupoff, almost snarkily observes that they look like Tharks.   Lupoff has a certain credibility with these things, after all, his contention that Gulliver Jones is the inspiration for Princess of Mars has a remarkable persistence.   For the record, here's the Lupoff's exact words:

“The book combines elements of Tarzan and Pellucidar, with just a touch of Barsoom thrown in for good measure.    Tam Evans is raised by Leang, a white tiger, discovers a lost underground world beneath Burma and fights Thark-like monsters there.  The four armed monsters are identified with hindu deities rather than the green men of mars, but as is so often the case, the reader is free to draw a different conclusion if he wishes.”

Apart from Hindu Gods, I'll also speculate that Kline may have been drawing on the giant, egg laying, four armed race of Theosophy, but that's just a speculation.

And that's all I've got, except that a search turned up (at ERBzine 1139) a magazine cover of Tam fighting a four armed blue-skinned giant riding a prehistoric animal.   So, not to say that Lupoff was making it up, but it's corroboration.    There's also another magazine or book cover for Jan of India, featuring a very lively looking four armed woman, suggesting that Jan may have encountered or heard of a similar creature.

Okay, Burroughs and Kline rode their horses pretty closely together in literary terms.   So its entirely arguable that Kline's Blue Skinned, Four Armed, Warrior Giants may actually be relatives of the Green Men and White Apes of Barsoom.   In other words, they may be a variant species of Thark.

Of course, the Green Men look pretty distinctive and distinctively non-human, while the Blue Warriors appear to have human faces and features.   There's no protruding ears on stalks, no tusks, no lizard eyes set wide apart.   Fatal?

Unfortunately not.   The Green Men are obviously closely related to the Great White Apes.  And as far as the White Apes go, Burroughs was at pains to point out that they looked far closer to human and terrestrial life than anything John Carter had seen up to that time.  Indeed, the recurring description of the Great White Apes says that they have a gorilla-like face.   Well, if that's the case, one could easily accept that the range of head variation between Green Men and White Apes could get you a creature with a much more human face.

So, we have to wonder.   Humans fit ecologically on Earth, and stick out on Mars, yet they exist on Mars.   Six limbed giants fit in on Mars, but not on Earth.   So where do Kline's giants come from, if they're not native to Earth?   Are they an expatriate Barsoomian race?   This seems likely.

But if so, how did they get from Barsoom to Earth?   There are three possibilities.   One is that the Tharks are actually a space traveling alien race from another star system who have settled in the solar system, peppering the three worlds with their offspring who have adapted dramatically on each planet.   It's a nice idea, but two problems.   One is that there's not a shred of evidence for it.  The other is that the Thark species are clearly indigenous to Mars, where there are other examples of six legged life, and even eight and ten legged species.

The second is that the Tharks hitched a ride with the Orovars when they were travelling through space a long time ago.   Well, its just barely possible.   Within Burroughs, there is some evidence that the Orovars were space travellers in their day, it's the best explanation I've got for the inhabitants of Thuria.   Beyond Burroughs, we have Kline showing that his ancient white martians were space travellers and left at least one colony in space, on the moon.   So its possible that the Orovars may have taken along some tame Tharks as slaves or colleagues, who then went native. 

The problem with this notion, apart from the thinness of evidence, is that the Tharks, if this is how they were transported, clearly underwent an extremely rapid evolution, morphing into their human- looking blue-man configuration.   Either that, or the Blue Warriors originally existed on Barsoom (and perhaps still do in some forgotten corner of Mars) but are now extinct or at least lost.   In which case, no rapid mutation necessary, because they were a pre-existing Martian race.

The third option is that if the Tharks are actually mutated or modified humans who have astral teleported from Earth to Mars and didn't quite get the jump right, then some Tharks might still have had the ability to Astral Teleport from Mars to Earth or Venus.   Of course, it would be reasonable to assume that if they could do this, given their mutation, they're probably not as good at it and probably more prone to further mutation with each jump.  So conceivably, Green Men or White Apes astral teleporting to Earth, found themselves turned blue and pushed towards a more human appearance by the jump.

And that's the best I can do for Tam's Blue Warriors, at least until such time as someone who actually has read the book fills us in with more detail.

But is this the only evidence for Tharks in Space?    Not quite.  Turn now to Ralph Milne Farley's ‘Radio Planet’ series.    This consists, loosely, of five books:   The Radio Man, The Radio Beasts, the Radio Planet, the Radio Menace and The Radio Man Returns.

In the Radio Man, a fellow named Myles Cabot accidentally builds a machine that teleports or astrally teleports him to Venus.  I wish I could have accidents like that.  Or maybe not, I might wind up on the planet of Russian Olympic Female Weightlifters.   When he arrives on Venus, he discovers Formians.

The Formians are described through three books as giant, horse-sized ant-men.   They have six limbs, they're black, they're big, and that's about as descriptive as it gets.   The earliest description comes in the first few pages of Chapter 2 of the Radio Man, when Myles arrives on Venus:
 

“And what was my horror when out of it clambered not men but ants!   Ants, six-footed and six feet high.  Huge ants, four of them, running toward me over the glistening sands.”

A few pages on:
 

“Then I fell to studying them.  First of all, I noticed that each ant carried on the back of his thoraz a line of peculiar white characters, somewhat like shorthand writing; and below it, several rows of similar writing, only smaller in size.  The peculiar green coloured weapon, slung in a holster on the right hand side of each ant, I had already noticed during the fight.  But apart from the white marks and the green weapons, my captors were absolutely naked; and so far as I could see, they were exactly like the ordinary black ants to which I had been accustomed on earth, only, of course, multiplied to an enormous size.”

Okay, so it sounds like they're merely just whopping big ants.   At another point, he describes them as ten feet in length.   But literally a paragraph later, Cabot starts to undercut his own description:

“But the ant who had brought me the water had a human look which relieved him of much of his terrible grimness.   In fact, he struck me as vaguely familiar...”

At other points, Cabot distinguishes among individuals, identifies some individuals as aged and infirm, some as young, some as delicate.     In the Radio Beasts, for instance, Cabot has no problem distinguishing young and athletic and worn out and old Formians.   I'd think that ants would pretty much all look alike.

At points they're described simply as giant ants, but starting with Chapter Three of the Radio Man and fairly regularly thereafter they're described as ‘ant-men’ which suggests that their appearance may be more human-like or more animal-like than we might assume.

The Formians are intelligent, as intelligent as the humans.   They're also sophisticated technologists and dexterous tool users, though Farley, in describing their hands simply calls them paws.   The fact that he's describing dexterous tool-manipulating members as paws rather than hands, suggests that there might be a little more to these creatures.  Unlike Ants, but like Tharks, the Formians have a long tradition of personal combat, and their record of duels are painted on their body.

The Formians are egg layers.    In the Formian colony, most of the legs are laid by a Queen.  However, subordinate Formians can lay eggs on their own, and even produce Queens.   Ants lay eggs, of course, but so do Tharks.

So are the Formians actually Tharks?   I suppose we could make an arguable case.   They are about ten feet long and six feet high, which means, standing up on two legs, they'd be on the same scale as Green Men of Barsoom.   They have six limbs, and they wear holsters on their bodies, as do Green Men.   They're jet black, but nothing stands on that, one way or the other..   They have, we must assume, triangular ant-like heads with antenna for radio transmission and well defined pincers or forceps.   Later on, we'll discuss how Green Martians might develop towards an ant-like or even more deviant head.  Their bodies include abdomen and thorax, since a thorax is specifically mentioned, though its not described in detail.

Myles Cabot, the Earthman, has never seen a Martian Thark or any other.   All he's got to work with, when he's confronted by black, intelligent, six limbed giants, is ants, so perhaps he's simply describing them in terms of what he knows, rather than what they actually are. 

One thing, if they are simply Tharks or a Thark subspecies, rather than giant insects, we can dance agilely right around the square cube rule.   Not, of course, that anyone in the pulp universe actually gives a hoot about the square cube rule.  Giant insects occur on Barsoom and other worlds.

There is a kind of metatextual piece of evidence to suggest a connection between the Formians and the Tharks.   Farley's ‘Radio Man’ was directly inspired by a Princess of Mars and the Barsoom stories.   Like Princess, Farley's Radio stories feature a wrap around structure where the hero returns and relates his tale to the writer.   Like John Carter, Myles Cabot is teleported to a strange world.  Like John Carter, he falls in love with, marries and has a baby with an alien Princess.   It's pretty much a naked rip off of Princess of Mars and no one has ever had a problem with that.

But if Farley is borrowing all these other elements directly from Princess of Mars and Barsoom, doesn't that also suggest that he is borrowing the Green Men?   And if he is, then where or what are his versions of the Green Men, if not the Black Formians?   It is interesting to note that as John Carter's best friend is the green man, Tars Tarkas, so too is Myles Cabot's best friend the black formian, Doggo.   In short, the Formians really are derived from or descended from the Green Men, in a literary sense at least.

So, like the Blue Warriors, I think that we might be able to attribute the Black Formians as another race of possible Tharks.

It's worth noting that in at least one collateral work, Rainbow Mars by Larry Niven, Burroughs Green Men appear, and Niven repeatedly describes them as essentially giant insect people.  So actually, the concept of Tharks in itself, seems to give rise or suggest insect creatures.   It's that whole ‘six limb’ thing, I guess.  (Although another six limb predator, the Apts of the polar waste, have faceted compound eyes, another insect-like trait).

The Radio Man, by the way, published in 1925, whilst Tam, Son of the Tiger, is from the 1930s.  So the Formians are actually the older of the two literary creations.

Farley in The Radio Man, and at more length in The Radio Beasts introduced a second race of horse-sized, giant, six-limbed, black and yellow striped, intelligent creatures.   These ones had wings to fly, and they were called the Whistling Bees.   Like Farley's Formians and Cupians, they communicate in radio frequencies, but they broadcast on two frequencies, and their communications frequency is inaudible to the other intelligent races. 

Unfortunately, the  information and description of these creatures is even poorer than the Formians.  So I can do little more than tentatively attribute them as possible Tharks.   There are a few indications, however.

As chronicled in the Radio Beasts, the Whistling Bees are intelligent, language-using carnivores, not instinct driven pollen eaters.  They also don't seem to be hive creatures, rather, consider this little conversation between Myles Cabot and the bee, Portheris:
 

 “If you Hymenerians have the intelligence to understand and to talk our language, how is it that you have no more sense than to attack the ant men, whose rifles render them invincible against you?”

 “I know not,” Portheris replied, “save that we cannot resist a fight.  I suppose it is the same reason that smaller insects seek a light, only to be destroyed.”

 “Then if you must fight,” Cabot suggested, “why do you not fight in swarms, and thus overwhelm your adversaries by sheer weight of numbers?”

 “It has never occurred to any of us,” the bee answered simply.  “We are an independent race.  We fight for love of fighting, rather than any desire for victory.”

Well, Tars Tarkas could not have put it better to John Carter.   Whatever the Whistling Bees are, they think like Tharks.

Are the whistling bees flying Tharks?    Well, special individuals among the Farley's Formians and Kline's Sabits are also winged.  So if they're good candidates, then so might the whistling bees.  Their shift to a different radio frequency would have taken them out of communication with the Formians, and caused the two races to diverge sharply.

Of course, there are arguments against including Formians and Whistling Bees as Tharks.   The Formians and Whistling Bees are described as giant insects.   Not necessarily fatal.  But the thing is that the animal life of Farley's Venus is dominated by giant insects of various sorts, including elephant sized monsters.   So, are the Formians and Whistling Bees Thark offshoots, or are they really insects consistent with the ecology and biological lineages of this area? 

According to the Priests of Kar in the Radio Beasts, the Formians (and presumably the Whistling Bees) are not native to Venus but came from offworld.    Other evidence indicates that they keep time on a 24 hour clock, just like Earth and Mars.   If that's the case, then they don't really have any common heritage with the insect life of the planet.   And if they've come from offworld...

Ralph Milne Farley's Radio Beasts also gives us a tantalizing possible Thark.   Let's consider this quote:
 

“Suddenly, a third creature landed on top of them all.  What manner of beast this newcomer was, Cabot did not know.   For it sized Cabot's body with what appeared to be two hands, and started tearing away the snake coils with what certainly seemed to be still more hands.  What could it be?  In all of Poros, Cabot knew of no animal with more than two hands.   All four extremities of his rescuer resembled human hands, and each of the four had six fingers as in the case of the Cupians.”

What could it be indeed?   The answer comes a few pages later:
 

“There entered one of the strangest creatures which Cabot had ever seen.  In general appearance it bore out the same relation to a Cupian as does a small gorilla to a human being on earth.  Its head was prognathous and deep set on the shoulders.  Its skin was hairless, except on the top of the head, and was the color of bluish slate.  Its arms were long and gangling.  It stood with a stoop and walked with a shuffle.  Like the Cupians, it was earless and had antenna, rudimentary wings and six digits on each hand and foot.  In the past, Cabot had occasionally heard of the legendary blue apes which were sometimes said to be seen emerging from caves in the Okarze Mountains, but never before had he seen one.....   His rescuer had had four hands, so had this blue ape.”

Well, good gosh!   So we have a creature with four hands an gorilla-like face, hairless except for its head and pale coloured skin.  This creature seems less intelligent than the Ants or Bees or Cupians, but it is intelligent enough to act as a servant.  Farley has slipped a close cousin of Barsoom's great white ape onto Venus.

Or has he?   After all, apes have hand-like feet, and nowhere does Farley say that this creature had four arms and two feet.   Perhaps it only has four limbs, and a hand on each limb?   Actually, that's the most likely explanation.

But if you want to split semantic hairs, we should notice that Cabot describes it as one of the strangest creatures he's ever seen...   And you know, this is a guy who is dealing with flora and fauna on another planet.  You'd think he wouldn't be all that startled by a blue gorilla, unless there was something else going for it.    And for the record, in his initial description of the creature, Farley refers to ‘hand and foot’, he doesn't describe the foot as hand-like.  So, the foot is clearly distinguished.   Finally, note that Farley's rescuer was using all four hands to pull the snakes off him.   But that doesn't make sense.   If he was four limbed, he couldn't have used more than three limbs without losing his leverage, to employ all four hands, he had to be standing on something else.   So, based on the reading, its very easy to interpret this creature as having four arms and two legs.

I'd note that on the Moon Maid, artists are always interpreting the Va-Gas as centaurs, based on Burroughs description of them as pony-like, when in fact, there's a detailed description which is not centaur like at all.  So given that, its pretty likely that an artist rendition could easily justify going either way.

What did Farley intend?   Oh, probably a four limbed creature.  But then again, he was a big Burroughs fan, so we can't rule out that he wasn't having a bit of fun (the light skin and the hairless body with the shock of head hair are very suspicious tip offs).   The description is vague either way, was this simple sloppiness?   Or was he being deliberately vague?  And for the purposes of this essay, should it matter?   I think we should accept the Blue Ape as at least a good potential candidate for a Thark race, perhaps a better candidate than the Pellucidar Ants.

Of course, there are arguments against the Blue Ape being a Thark.   It's the only Thark candidate which is not gigantic, being roughly human sized.  But then, that's not really fatal.   Dwarf species are common in biology.   More difficult is the fact that the Blue Ape shares a series of features with the Cupian humans, six fingers, vestigial winglike structures and antenna.   Its unlikely, but not impossible, that evolution would drive a similar set of adaptations in a dwarf Thark and a human.  On the other hand, we don't know that these adaptations are the result of natural evolution, or what sort of pressures were at work.   So, it diminishes the probability somewhat, but it doesn't eliminate it.

Let us turn back to Otis Adelbert Kline, whose Planet of Peril was published some five years after Ralph Milne Farley began his Radio Man series.   Farley had already written several famous books on Venus, and in them, he had included giant ants and bees.

Kline, in Planet of Peril, introduced what he called a race of giant intelligent termites.   These creatures, called Sabits, were six limbed, they laid eggs, they were ruled by a king and queen.  In some respects, their behaviour was similar to ants, particularly in handling aphid like creatures and human slaves.  They communicated verbally with their human slaves.   Here's Kline's description:
 

“Something darted out and ran towards him on its six horny legs with incredible swiftness.   The creature was about the size of a small Shetland pony, with eyes as big as dinner plates set in a head more than two feet across.   Its jaws were armed with sharp mandibles and a pair of forceps large enough to encircle two men.   The entire body was covered with glistening ivory white armour.  It came at him with forceps extended....”

The size of a Shetland pony is also used to describe Formians.   These Sabits have huge eyes, a peculiar feature, but something similar is found in the Thark's Barsoomian relative, the Apts.   The Sabit's have huge heads and giant forcep mandibles, which are definitely outside the physical descriptions we associate with either Green Men or White Apes.  But then again, the Thark species may be prone to dramatic mutation.   Frankly, the range of heads between green man and white ape, we've suggested, could justify a Thark with a human face.  It could just as easily go the other way and justify a Thark with an insect face.

Lets stop a second and explain that.  How do we get from a green man face to the ant-like face of the Formians or the giant heads of the Sabits, both with their great big forcep mandibles? 

Actually, its not all that hard.   Green Tharks on Barsoom already sport gigantic tusks.  So we really only have to posit two developments.   The tusks get bigger, and they become moveable. 

Moveable tusks or teeth?   Isn't that out of the question?   Again, not really.   Teeth are not actually fixed in the bone, rather, they fit into sockets and are held in by a spongy network of ligaments.   The idea is that the spongy ligaments absorb shock, so that you don't wind up with hairline cracks in the teeth or jaw.  So actually, your teeth are already loose and slightly moveable.  For better motion, you need only add some muscle to the ligaments, and open up the socket a little.   Poisonous serpents on Earth have poison fangs which are extendable.   It's not impossible that Tharks might also evolve their jaws and tusks to reposition their tusks for attack or for rest.  A bit more evolution, and you might actually be able to use them together.   It's a bit of a stretch, but not impossible.

Now, assuming that as the tusks become more flexible, moving more like jointed limbs, they get larger.   Suddenly, we're attaching a lot more muscle to these larger moving tusks.  Where does all that muscle go?   It anchors to the side of the head, allowing the tusks to pull inwards, meeting up in a pinching motion.   The Thark's tusks are now two or three times their original size, say, and to support it, the head has become massive and triangular.  Vaguely ant-like.   We've arrived at Farley's Formians.

Okay, now take the Formians and push them even further.   Make their tusks really really huge.  Say a yard or more in length.   That's a lot of weight to carry, and even worse, tusks that large are going to have massive amounts of leverage for torque.   The neck has to thicken immensely, with the muscles and vertebra of the neck becoming extremely large and powerful, or our Thark is going to be walking around with a permanent risk of breaking his neck   Meanwhile, the gigantic muscles necessary to support all that tusk leverage are anchoring on the head, which becomes larger and thicker, perhaps as broad as the body, with little apparent neck.   Congratulations, we've arrived at the Sabits.

The point is that Formians and Sabits heads may well be a reasonable extension of the variation of Green Men and White Apes.

There are aberrations with the Sabits.  Their king has vestigial wings.  But then, the whistling bees are winged.   Their life cycle includes eggs and larva.  But once again, that doesn't necessarily mean that they're not Tharks.  It just means that they're Tharks with wrinkles.

And of course, neither the earth hero, Robert Grandon, nor the Venus heroine, Queen Vernia, have ever seen Martian Tharks.   So they're limited in how they can describe the creatures.

Looking at it metatextually, I'm almost certain that Kline chose to make his Sabits (or describe them as) giant termites, rather than giant ants or bees, because Farley had already used giant ants and bees.   Kline chose the last remaining colonial insect, specifically because Farley had not used it. 

This is a bit of a guess though, since although Kline's Planet of Peril was published well after the Radio Man stories, he'd actually written it before Farley's stories saw publication.   So the Sabits may have been ‘termites’ all along.   On the other hand, Kline was well aware of the Radio Man stories, and acknowledged the similarity of setting.

If that is the case, then Kline's Sabits are, in a literary sense, children of the Formians who are themselves descended from Tharks.   Or put it another way, the Sabits are literary grandchildren of Tharks.

This brings us back full circle to Burroughs and Pellucidar.   In one of his Pellucidar novels, the Land of Terror, at chapters nineteen through twenty-one his protagonists is captured by what they describe as giant ants.   Six limbed, intelligent or semi-intelligent creatures the size of Shetland ponies....   Tharks?   Maybe....

Or maybe maybe not.   The Pellucidar Ants are a lot smaller than the other Tharks, being about six feet long and no more than three feet high.   They show no signs of speech, and no particular intelligence greater than that shown by actual colonial insects.     The descriptions and behaviour of these creatures seem far too ant-like, they're even plagued by a gigantic anteater.  Let's take a quick look at their description:
 

“The creatures were of enormous proportions, their bodies being fully six feet long, the highest point of their heads being at least three feet above the ground -- and such heads they were! These enormous heads presented a most ferocious appearance with their huge eyes, their jointed antennae, and powerful mandibles.... I noticed that some of the ants were larger than others, and that the larger ones did no work; and then I noticed that their mandibles were much more powerful than those of their fellows, and I realized that they were the soldier ants guarding the workers. .... notwithstanding their large eyes it is possible that they may be blind, as some species of ants are; but ants do not need to see, since they are furnished with delicate organs of hearing in the head, in the three thoracic and two of the abdominal segments, and in the shins of the legs, in addition to which their elbowed feelers or antennae are abundantly supplied with tooth-like projections connected with nerve endings which function as olfactory organs; therefore, though they might not be able to see me, they could certainly hear me or smell me-at any rate, they knew I was there; and several of the great soldier ants started toward me....  One look at those terrible faces and formidable mandibles was enough. I turned to beat a retreat;”

Sounds like ants to me.   With Farley and with Kline, its possible to read ambiguity into their Formians and Sabits.   There isn't really much more than a few paragraphs of good description of either, so one can sort of look at what they don't describe, the lack of description and detail, and say “well, normally, we think of insects, but you know, this could be just as consistent as being Thark-like.”   We can play games with Blue Apes because the description can support ambiguity.

Well, I don't think we can say that with Pellucidar Ants.  Burroughs piles on too many details of appearance.   But there's not much ambiguity to play with in the Pellucidar Ants.   And worse, he goes on to pile on details of behaviour.   These creatures not only look like regular ants, they act very much like regular ants.   At one point, the ant that's carrying David Innes has difficulty bringing him into its burrow, its carrying him crosswise so he won't fit.  Like a typical ant, it tries several times.   On the whole, I'd have to exclude the Pellucidar ants as a variant race of Tharks.  If they are, then oh how the mighty have fallen.

But again, there's a kind of meta-textual evidence.   Farley wrote two ‘Pellucidar’ novels, the Radio Flyers and the Radio Gun Runners, about an inner world very similar to Burroughs Pellucidar.  Farley joked that they both read the same book about an inner world theory.   Well, if Farley was writing a Pellucidar novel, perhaps Burroughs simply returned the favour and tucked Farley's Formians into his own Pellucidar.    In which case, the Pellucidar Ants may well be the literary grandchildren of Burroughs own Tharks. 

Finally, and this is stretching the borders, there is a final possible Thark race to mention, although these creatures do not appear directly in either Burroughs, Kline or Farley.  (Or perhaps they do in certain short stories).   This race of Tharks, of course, are the Centaurs of Greek Myth.   Six limbed beings who travel on four legs.   Although so far as I know, none of these writers made use of these mythical beings, they were all well aware of it, and Centaurs would be part of the mythology of their shared world.

Now, the thing is, in Burroughs and Kline's Universe, some myths are real.   Atlantis and Mu did indeed exist, the city of Opar was founded by Atlantis.   There are Chinese Dragons on Maza's Moon.  So, if some myths are real, then quite possibly others are too.

Oddly, though Burroughs never actually used Centaurs that I know of, many of the illustrators of the Moon Maid tended to draw the Va-Gas as feral Centaurs.   The trouble is that the Va-Gas in descriptions are pony-like humanoids, but very clearly four limbed.   The creatures that appear on book covers are six limbed.  Go figure.  Perhaps centaurs did once appear on the moon, and are still recorded in the art.   Frankly, I'm not buying it at all.   Burroughs and Farley and Kline are all text, its written there, its canonical.   Artists representations are not, they just got it wrong.

The Theosophical Giants are not creatures of either mythology or fiction.   Rather, back in the 19th century, there was a new age movement which claimed to psychically relate the original history of Earth.   Big Whoop, right?

Well, this is outside my bailiwick, but there is an argument that Burroughs ran across this stuff, and it consciously or subconsciously influenced him (or he stole it) in building Mars.  Among the Theosophical chronicles were a red race of humans, airships that flew and warred using mysterious rays (Vril), and a race of four armed giants.   In one of those weird coincidences, the Theosophical history was written by a gentleman named Arnold...  Who just happened to be the Matthew Arnold who wrote Gulliver Jones, who some have argued inspired or influenced (or was ripped off by) Burroughs in writing the Princess of Mars.   The notion, I believe, was originally advanced by Fritz Lieber.

For more detail, you might refer to the Sword of Theosophy articles written by Dale Broadhurst on Bill Hillman's site.  There is a description from this text worth quoting:
 

“In 1888 Blavatsky published her magnum opus, The Secret Doctrine, wherein... we are told that man has evolved through seven Root Races... The Third Root Race were the gigantic, apelike, hermaphroditic, egg-laying Lemurians, with four arms and eyes in the backs of their heads....”

So, were the four armed Giants of Theosophy literary ancestors to Burroughs Tharks?   And if so, should we include them somehow as another Thark species?   I dunno.  I'm against it, but I suppose it can be argued.   It's all just an intellectual game, after all.   But if I were going to include them on the list of possible Thark species, I'd probably rank them behind Centaurs and ahead of Moon Centaurs in probability.

Assuming that I haven't completely lost my mind, and that these assumptions about a Burroughs/Kline/Farley shared pulp universe all hold together, what does this tell us about the Thark species?

What conclusions may we draw about this variety of races?   The Tharks almost certainly originate on Barsoom.   There are other distantly related six legged species, and some of the other six legged species seem to show features that appear in Tharks on other worlds, like the huge eyes of the Apts.

One consequence of their being from Barsoom means that the heavier gravity of Earth and Venus pose problems for them.   This is probably why so many of the Thark races on other worlds go on all fours or all sixes.    The Sabits are climbing thousands of feet of vertical trees in near-earth gravity, so clearly they need to use all six limbs.   The Formians, staying on the ground, alternate use of four and six limbs, as do the Pellucidar ants.   Centaurs stick with four travelling legs.  Blue Apes have adapted to heavier gravity and other conditions by reducing in size.

Of the Thark races of Venus and Earth, only the Blue Warriors appear to normally go upright...  And the Blue Warriors, if we go by Tam's magazine cover, are an equestrian race.   Like the Green Men, they ride, they don't need to walk much.

It appears that some of the Thark races of other worlds are armoured.   Armour is mentioned for the Sabits, although its not quite clear from the text that this is natural armour, its also remotely possible that it is plate armour that can be put on and taken off.   It seems likely that the Formians and Pellucidar Ants are armoured.

All of the Thark races appear to be intelligent, though the White Apes of Mars, the Blue Apes of Venus and the Pellucidar Ants (I'm not persuaded that they're really a Thark race, I'm just including them to be comprehensive) may not be rocket scientists. 

All of the Thark Races (with the possible exception of the Blue Warriors) are egg layers.   There are repeated suggestions of something more complex than simple eggs.   The Sabits for instance, have a larval stage.  Interestingly, the Green Men can examine their eggs and apparently judge the physical characteristics of the juvenile within...    And even more interesting, Green Man eggs ‘grow’ from the size of a goose egg to large objects that would fill a small barrel. This suggests that the Green Men themselves may have a concealed larval stage in their egg history.

One peculiarity is that some of the Thark races, the Sabits, Whistling Bees and Blue Apes of Venus, may have wings.  The Whistling Bees can fly.   Is this a wild assed mutation, or part of the Thark Genome?    One could understand why the ability to fly, or sprouting wings, would not be popular on Barsoom.

All of the Thark races are social with each other.   Three of the nine (Sabits, Formians, Pellucidar Ants) appear to embrace colonial lifestyles with dominant females (Queens) laying eggs for most of the community.   Well, we know from Burroughs that the Green Men are pretty fast egg layers, so its entirely possible that the Green Men or Thark genome can organize its society this way.   We do know that this is not the only route for the colonial Tharks, individual Formians can lay their own eggs.   So the Queen based society is a choice for Formians, its not their only option. 

For creatures like the nomadic Green Men, a queen based society is not all that viable.   Five of the races (Green Men and White Apes of Mars, the Centaurs and Blue Warriors of Earth, and the Whistling Bees of Venus) seem to be more individualistic and warlike.   We don't know enough about the Blue Apes to say one way or the other.

The single biggest variant among the Thark races is their heads.   The White and Blue Apes look like Gorillas.   The Blue Warriors and Centaurs look relatively human.   The Formians and Pellucidar Ants look like insects, as do, presumably, the whistling bees.    The Sabits and Green Men just look as weird as hell.

We've previously discussed some of the reasons for the peculiar facial features of Green Men and White Apes, in our previous article.   In this article we've touched on possible explanations for the peculiar facial features of Formians and Sabits.  The non-martian Tharks might be worth a further examination, to see if their peculiar characteristics are influenced by their environment.

Consider the Sabits.   Their habitat is a large valley covered with immense giant trees thousands of feet high.   We can assume that their environment is moist and lush, and that there is little or no direct light.  They inhabit tunnels at the bases of the trees.  So, its likely that they would have large eyes for low light or diffuse light conditions.    Their lifestyle depends on climbing up vertical trees, so its likely that all six limbs have to used for locomotion and climbing.  Going straight up and down takes a lot more strength than walking around on a flat plain.   With all six limbs committed, in order to grip, they need to use their mouths.  This means, in part, the hyperdevelopment of the tusks found in the Green Man into large moveable forceps, and the thickening and enlargement of the head and neck.

The Formians and Pellucidar Ants, perhaps because of a tunnel based, hive lifestyle, appear more insectlike.  They too have forceps, larger than a Green Man's tusks, smaller than a Sabits.

Creatures like the Blue Warriors and Centaurs have much more human facial features.  Obviously, the factors that lead to Sabit, Green Man and White Ape faces are absent.  We don't quite know what environmental factors lead to humans looking like we do, rather than apes.  So we can only assume that the same factors are at work.

One thing about being rapid egg layers, and being able to suss out the likely qualities of the eggs or larvae quickly, is that the Tharks can adapt or mutate themselves with extraordinary rapidity.   They may well have self selected the characteristics of the various races we see.   Indeed, there is evidence of that racial self selection in the Sabits, since each Sabit colony has a different colouration.

It is not clear how the various races of Thark have emerged, or how rapidly they might mutate.   However, the evidence would suggest that the Thark may mutate or diverge far more rapidly than human.   Human generations are 25 to 40 years.   A Thark generation may be as little as five to ten years.   Humans will produce only a handful of offspring per couple, and must wait as long as a generation to fully assess their potential.   Tharks may produce dozens of eggs a year, hundreds over a decade, and they seem able to assess their potential much, much earlier in life.   Thus, Tharks may diverge or adapt at as much as 80 to 300 times the rate of human adaptation.   This would produce radically different races in a relatively short time span. 

Looked at very strictly, its all nonsense of course.  The only possible relative of the Green Man is the White Ape, because both were created by Burroughs, existed in the same books, and clearly were intended to have a relationship.

But having said that, I think there's a case to be made.   At least two other writers, whose names have been tied to Burroughs, who were contemporaries of Burroughs, and who wrote specifically Burroughsian-style adventure tales on other planets, created several races of six-limbed, intelligent, warlike, inhuman giants all about the same size as Burroughs Tharks, in books that were obviously derivative of Burroughs Martian books.   For several of these races, we've got a degree of overlap which suggests in some case, a deliberate borrowing, and in others, at the very least a strong unconscious tribute. Who is kidding whom?

In a sense, its all a sort of literary game, looking for evidence of one set of creatures, pretending the worlds of these writers all interlap and interlock.   But, if we can find evidence and make a reasonable case, then why not have a little fun.  Perhaps it will come in handy in someone's role playing game or effort at fanfiction.

I suppose there's a very farfetched apocryphal case for a couple of possible additional races of Tharks: The Theosophical Giants, based on a muddy and unproven hypothetical; and the Centaurs of Va-Nah, based on literally generations of illustrators getting it horribly wrong.

Bottom line, we've got possibly eight or nine possible distinct races of Tharks spread across three planets.    There are the Green Men and White Apes of Mars, the Blue Warriors, Centaurs and Pellucidar Ants of Earth and the Formians, Sabits, Whistling Bees and Blue Apes of Venus.