Friday 22 March 2024

A psychotherapist space spider

The recent Netflix film 'Spaceman' is an adaptation of the book Spaceman of Bohemia, written by the Czech/American author Jaroslav Kalfař. It is about a lone Czech astronaut travelling a long distance in the solar system to investigate a strange space cloud. A major theme of Spaceman is the loneliness of the astronaut. If you like philosophical themes and are not in a hurry, Spaceman is well worth watching; however, those who prefer ray guns and explosions might like it less.

But this blog is about speculative biology of the extraterrestrial kind, not about film reviews. While the astronaut, Jakub Procházka, is lonely and far away from other people, he is not alone. I am not talking about the ship's cat here, not that seems to be one. An alien being that is best described as a spider the size of a small child shows up aboard. How is unclear and you will probably wonder whether the spider is real or whether we see a hallucination springing from Jakub's too lonely mind. The internet seems full of discussions of that particular topic, so I will not discuss this. Well, in fact, you do see a small spider moving under Jakub's skin in the beginning of the film, which seemed to me a strong hint that the spider originated inside Jakub, not as a physical being, but as a concept.    

Anyway, the nice thing is that we get to see the space spider in sufficient detail to analyse it as a speculative biology entity. 

Why is it called a spider? You wouldn't expect alien beings to conform to Earth cladistics, after all. But there are certainly similarities. It has eight legs with long slender elements sticking out sideways. There is a big bulging abdomen, as well as a head. If it would be a proper Earth spider, that head should be fused with the trunk to form a cephalothorax, but this space spider head seems movable relative to the trunk part. The head has six eyes, not eight, even if some reviews mention eight. 

Click to enlarge. Nentwig et al. All you need to know about spiders. Springer 2022 

 
Click to enlarge. Nentwig et al. All you need to know about spiders. Springer 2022 

The eyes of Earth spiders are quite interesting and variable between families of spiders. There are not always eight, in fact, and six is definitely possible with Earth spiders. The two images above show that clearly. The eyes of our space spider, christened Zanuš by Jakub, appear to have pupils. The eyes seem immobile, and they are enclosed by a ring of elastic tissue, allowing them to become larger and smaller in apparent diameter. That is a clever trick that helps convey emotions. There are two large eyes and four smaller ones, but otherwise they all look the same. On Earth, different  eyes have different functions, and that shows up in their size, colour as well as the apparent direction they seem to be aimed in. We will get back to that later.

There are two very large cheliceres pointing straight down from underneath the head. I haven't seen Zanuš using these fangs and do not know what they are for. Then again, what can fangs be for? It does make you wonder what these space spiders do in their natural environment.


There are additional limbs around the mouth, and in one touching scene, shown above, Zanuš accepts a spoon from the astronaut with some food on it. These mouth limbs can then be seen to be tentacles, and tentacles are definitely not in the anatomical repertoire of Earth spiders.

There is one more big departure from the Bauplan of Earth spiders: Zanuš is obviously endoskeletal, as can be seen from the clip. There are tendons connected to bones, and the entirety of the body is covered by hairy skin. This is certainly not an exoskeletal joint with hinges open to the outside world. The joints are, like vertebrate joints, well and truly inside the leg. The legs, by the way, end in two prehensile fingers each. Zanuš clambers around the inside of the spaceship grasping objects with these tiny hands.

So what does all this suggest? A first explanation is that, if Zanuš is a figment of Jakub's imagination, Jakub knows very little about spiders. I doubt that real astronauts get much zoological training, so that is fine. A second option holds that Zanuš is a real being; inside the story, of course. If so, his Bauplan is interesting, and we will get to that. The third level is the one the creature designer and film makers used: why did they choose this design? 

Let's play along and see what we can make out. We have an endoskeletal animal the mass of a small child, with lots of fairly thin legs sticking out sideways. The legs, fur and locomotion all suggest a terrestrial origin; this is not a swimming animal. The legs are very spindly and stick out sideways; that, plus the presence of tentacles, suggests a world with very low gravity. The ability to grasp objects all around further suggests that the creature would be at home in a 3D environment, such as tree branches. 

Click to enlarge. Nentwig et al. All you need to know about spiders. Springer 2022 

One thing bothers me in all this: Zanuš' eyes all look in the same direction. In a 3D environment, it pays to be able to look in most directions at all times. If your Bauplan has multiple eyes, it makes sense to move some to achieve all-around vision. Spider eyes follow that principle, at least for some families, as shown above. In contrast, if your Bauplan only provides two eyes, which is a poor choice if you ask me, then evolution can be expected to place them where they do best. Here, they would be seeing what you eat and also covering as much of the world as possible. Not surprisingly,  the eyes of many fishes and birds that do live in a 3D environment are placed at just the right spot to achieve such goals. Of course, many birds and mammals have eyes that  depart from that pattern. If you only have two eyes, stereoscopic vision can apparently outweigh the need for wraparound vision. With multiple eyes, you can easily get it all, but Zanuš' eyes all look ahead. That seems odd.

In the story, Zanuš proves to be a thoughtful and respectful psychotherapist. You need good eyes to pick up tiny nuances in expression, posture and movements that tell you a great deal about someone's state of mind, but not eight ones!

A final word in this rather meandering post. I cannot speak for the general audience, but I quickly liked Zanuš, perhaps because I am not really afraid of bugs and small arthropods. I rather like it that the film makers dared choose a shape that many people find repulsive. I do not know whether many people actually turned the film off, disgusted by Zanuš' spider shape. I hope not, because the world could do with a bunch of sympathetic Czech/alien psychotherapist space spiders. Then again, I still wonder what Zanuš' people use those enormous fangs for on their home world...



Sunday 25 February 2024

No Fish in the gutter!

The realisation that publishers were probably not interested in my book forced me to reconsider several aspects of producing The Book in spite of that, which is one of the reasons I haven't written a post in some time. Another one is that I now also devote part of my creative time to a completely different type of art (I draw city views in the 'ligne claire' / 'klare lijn' style).  

The things I need to reconsider are those that an author would normally leave to publishing professionals: content and language editing, typesetting, lay-out, public relations and perhaps more.

I started with the language aspect. Even though the book is about images the text still counts some  45,000 words, so it pays to get that part right. I asked Biblaridion, who produces a very thorough YouTube series on designing an alien biospheres, whether my English would be good enough for a UK context. He was kind enough to have a look at the Furaha Book Sample (thank you!) and had only a few remarks, which was encouraging. Thinking matters through, I still decided to ask for professional writing advice. As most readers of this blog come from the USA, I will switch to US English, or I might produce more than one version. Next on the list is improving the layout; I have now looked at various self-published books on Amazon, and many of them looked wrong in one or more respects. The problems could have to do with character spacing, titles that did not seem to be on the right spot, columns with too many characters, wrong use of white space, or a too narrow page gutter. The more worrying ones were where I could not put my finger on a specific problem, which indicates I am not proficient enough to pinpoint what is wrong. There may be matters that I do not even spot as wrong but that a professional would identify immediately.           

I also realised that using two-page illustrations may not be wise: while they can look gorgeous, there is a chance that the most interesting part of the painting will disappear in the gutter, which is where the two pages meet. I used several such paintings and made the mistake of putting the centre of attention on the centre of the painting. That has to be corrected, and this post is about one such spread. 

Click to enlarge; copyright Gert van Dijk

The image above shows how the spread introducing the 'Fishes-IV' group looked a few years ago. I know the text on the image says 'Fishes V', not 'IV', but that is due to a cladistic revision). As two-page illustrations go, it was not too bad, because there was nothing of great interest in the gutter. But this painting predated the 'Great Hexapod Revolution', meaning their head anatomy changed completely. 

Click to enlarge; copyright Gert van Dijk
 

This was the succeeding stage. The animals, now 'Fishes-IV', have evolved and have an updated head anatomy, with proximal and distal necks and complete separation of the neurocranium and the gnathocranium.  The background animal now is a filter feeder, using much modified lateral jaws as sieves. The 'cheek opening' allows water to leave the mouth when the mouth cavity is put under pressure by closing of the upper and low jaws. I must revisit that design one day, but I am not satisfied with it. And there is the gutter matter...   

I will need a new spread page to introduce the Fishes-IV clade. Above are four results of playing with the design, done in ZBrush. They generally look like plesiosaurs, don't they? Well, if you have a swimming animal propelled by flippers and teeth at the end of a long neck, evolution is going to smooth streamline it, so it will end up looking like a plesiosaur. Can't be helped...

Click to enlarge; copyright Gert van Dijk

Variant A is fairly general. Note I did not work on the jaws; these 3D designs are merely aids to help painting, not goals in themselves. The three pairs of flippers are arranged in 'ascending staircase' fashion, with the first pair place lower and the last pair higher than the middle pair. In this species, the middle pair provides most thrust.       

Variant B is a fast swimmer with much-elongated necke. The lateral jaws are elongated but flattened and help to catch or cage prey, then chopped into coarse pieces by the short upper and lower jaws.

Variant C has an unusual body shape with lengthwise 'shoulders' supporting the fins. The shoulders do not make the frontal cross section much larger than the general rounded shape, and should not offer much more drag, but I must check that before I commit the design. The fins are arranged in 'descending staircase' fashion.

Variant D is a big blob sitting on the sea floor. It eats armoured shelled prey and has heavy upper and lower jaws to crunch the shells. It has no need for speed at all and is itself armoured.

As you can see, work on The Book continues. While distracted by layout matters, I can't help thinking about new and interesting creature designs. How about marine wadudu, that could grow much larger than terrestrial ones; with a mesoskeleton they could in fact compete with all those 'Fishes'. I have also been thinking about plants that would thrive in shallow seas, making empty beaches on Furaha rarer than they are on Earth. Or plants that actually form nets, not just branching structures.

But before I start dreaming about The Book Volume II, I had better finish 'The Book' itself.     

Monday 8 January 2024

New directions for The Book

This is the first post of 2024. It has been too long since the previous one. The explanation for the long delay consists in part of various things that have absolutely nothing to do with the Furaha project, but some other things were relevant. Quite relevant, in fact.

I visited TetZooCon in the beginning of December. It was great fun as usual: have a look at Darren's report here. I went there in part to speak with publishers or other knowledgeable people who might tell me more about my chances were of getting a publisher interested. I was lucky enough to speak such people, including a publisher. The discussions were open, and everyone was friendly, but the message was that there was hardly any chance of getting the book published by a large publishing house. That was disappointing, mostly because I had felt that getting a publisher to commit would be a sign that the work was good enough for that. Then again, as someone explained to me, even if you do get a publisher to print the book things can still go wrong: for instance, if those responsible for distribution put in little effort, nothing much will happen.

What it all boiled down to was that I might as well go for self-publishing. As one person said after seeing my sample part of The Book, now that I have already done most of the work, I should consider doing the rest as well.

I ruminated on that for a while, and finally decided that this is probably the way to go. At present I am thinking of Amazon, having seen an example of their quite acceptable print quality. Another advantage is that Amazon is accessible to most of my audience.

There are disadvantages too: a professional publisher should be able to prevent me making basic mistakes in book design, writing style or any other aspect of publishing.Without one, I am free to make all those mistakes! A major hurdle may be advertising: I will need a way to tell the wider world, once the time is there, that The Book is out. But those should be surmountable obstacles.

At present I think that The Book can, in principle, be available one year from now. I plan to have it published as actual physical books, not as e-books. Among the things you may expect in the coming months is a much-needed update of the Furaha main site, as well as posts about reworking some paintings for The Book' publication.            

I'll be back...

 


 

Sunday 12 November 2023

Shaping hexapod shapes: high browsers

 First of all, I apologise for taking so long to post something. I have been much too busy writing large reviews. Some of you probably hoped that I was busy dealing with publishers to shape The Book. If only! At present it seems that sending manuscripts to publishers in the way they want you to has as much apparent effect as shouting in a vacuum. Do you remember the slogan 'In space no-one can hear you scream?' It's like that. If you didn't know the slogan, it's from the first Alien film (1979). Rather like that particular alien I intend to keep coming back, though.

Nevertheless, I did toy with the directions evolution might take the hexapod design into. The fun of doing something like this is that you must follow the rules, and these state that the basic anatomy is a given, exactly like in real biological evolution. In this case, the challenge was to evolve a high-browsing animal, something like a giraffe or possibly a sauropod. One way to get an animal's mouth high up into the air is of course to enlarge the entire animal but that is rather boring. Other solutions would be to stretch all animal parts vertically, or to only stretch parts close to the mouth, such as the mouth parts themselves, the skull and  and the neck. I chose somewhere in between the last two choices: legs are elongated, but not as much as the neck. Or necks.

Hexapods do not have vertebral columns in the sense of one chain made out of a large number of short bones. Instead, they have two parallel chains together forming a 'scala' (ladder). In the neck the original two series of bones forming the stiles of the ladder merged into one structure while the rungs disappeared altogether. This happened early on, when hexapods were sea dwellers, as an obvious way to expand the range of the mouth at little cost. With a long mobile neck you can increase the 'feeding envelope', which is the volume the mouth can reach while the body stays still. The same idea applies to sauropod necks and rusp mouthparts (see here). As you may have noticed from earlier sketches (here and here), hexapods first have a proximal neck of two segments, then a sensocranium, a distal neck of two segments and finally the jaw apparatus. 

Click to enlarge; copyright Gert van Dijk

 

Click to enlarge; copyright Gert van Dijk

Here are two sketches in which I played with such a high browsing hexapod scheme. I also stretched the sensocranium. Normally that is just a bulb sitting above where proximal and distal necks approximate one another. Here the neurocranium is truly a part of the chain of segments. If you look closely, you will see some curved lines gradually following the angled neck bones. That is the asymmetrical oesophagus, situated on one side of the animal, not in the middle below the bones. See here for more on that odd feature.     

Elongating the neck in this way involves elongating the individual bones. I felt that such animals should be able to hold their necks horizontally, not just vertically. Such a horizontal posture will stress such long bones though. Here's why: take one such long bone and assume that the proximal end (near the body) is fixed. All bones attached at the distal end then act as a weight to pull that distal end down. This weight tends to bend the bone down, which stretches the top margin of the bone while simultaneously compressing the bottom margin of the bone. Bone tissue is usually better at withstanding compression than tension, while tendons have opposite characteristics. A typical vertebrate trick to solve these stresses is to string strong tendons along the upper surface of the backbone to take care of those tensile forces, leaving the bones themselves to deal with compression. The trick works better when the tendons are at some distance from the centres of the vertebrae, and that is what neural spines, the bone projections sticking out of the top of vertebrae are for: they keep the tendons at a distance.

Click to enlarge; from Preuschoft & Klein 2013

The image above shows a scheme with vertebrae, spines and a big tendon in place for a sauropod. In the drawing, the neck vertebrae are fairly long, so we are getting close to  hexapod anatomy. But do extra-long bones pose additional problems? 

Click to enlarge; copyright Gert van Dijk

I am still considering that and can at present only offer some thoughts. Let's start with one spine on each bone; there are tendons running from the spine that bridge the joint on either  side (A). That means the tendon is attached at a sharp angle to the bone, whereas it would work better if the attachment were nearly vertically. That can be done by making the spine longer, or, in this case, by placing it near a joint (B). That works well for the closest joint but worse for the farther one, so that tendon now attaches to the bone itself and no longer crosses a joint. It still looks as if the bones would have to withstand lots of bending forces, which we do not want. Very well, let's duplicate the 'spine & tendon structure' so we have a spine at each end of the bone (C). But just to be safe we may add an additional ligament crossing all elements (D). So there we are.

Click to enlarge; copyright Gert van Dijk

A new problem now may be that flexing the neck might bring one spine into contact with the other, preventing the movement. That can be solved by moving the spine away from the joint again, but there is another solution. We already allowed the oesophagus to be asymmetrically placed to one side of the animal. Could we also place the distal and proximal spines off-centre, so one is displaced towards the right and the other towards the left? That is shown in the image above.

Do the rules allow that? We are all used to the fact that vertebrate skeletons are nicely symmetrical when our intestines are not all that symmetrical. I wonder why; anyway, there are skeletal exceptions, such as narwal teeth and crabs that have one big and one small claw. My guess is that large anatomical asymmetries between walking legs would make both the mechanics and the neurological control of walking extremely difficult, without offering any advantages whatsoever. (Mind you, quite a few neurological functions are already asymmetrical even when the underlying anatomy is nicely symmetrical. Humans have handedness, but also 'footedness' and 'eyeness'; bees have 'antennaness', and I could continue). Anyway, anatomical asymmetry in a nonlocomotory part should not cause any major problems. So perhaps we can add a new rule stating that skeletal asymmetry occur in Hexapods. I must think some more about that and will try to find out whether anyone has already solved the riddle why vertebrate innards are more asymmetrical than their skeletons.





Sunday 10 September 2023

What's a head? Or a neck...

Yes, it's a silly title. Isn't a head, rather obviously, that part of an animal where vision and hearing are gathered, along with their associated neural processing units, as well as air and food intakes, along with whichever specialised organs that takes? For air intake, you could read 'nose', and for 'food intake' there is the whole complex assembly of jaws, teeth, a tongue as well as an oesophagus. 

That seems right for humans and other terrestrial vertebrates, but a few moments' thought reveals that 'obviously' does not belong in this 'definition'. Fish have heads but take in water, not air, so the 'air intake' should become an 'inlet for gas exchange'. The hearing organs of many arthropods are not in their heads, and so the associated bits of brain need not be in the head either. The description supposes that the rest of the animal is distinct from the head. But in octopuses there is no distinction between head and body, with the limbs ('arms' that are not accompanied by 'legs') attached directly to the head/body unit. For spiders a similar point can be made that the head is merged with part of the body. 

I could go on, but the point is that a 'head' is not as clear an entity as you might think. A 'head' is the result of 'cephalisation', described by Wikipedia as 'an evolutionary trend in which... the mouth, sense organs, and nerve ganglia become concentrated at the front end of an animal, producing a head region.' I like 'head region': it provides the looseness we apparently need to describe what a head is. 

Furahan 'Scalates' certainly underwent cephalisation, and their heads definitely contain eyes (four of them) and ears, in terrestrial forms (also four) along with enough brain to do the heavy duty processing these organs require. But the 'intake for gas exchange' is not in the head at all. The intake for food is there, with jaws (originally six, later four) at the front of the animal, so clearly these are in the head. Well, that depends... 

Click to enlarge; copyright Gert van Dijk

A clade of Furahan Fishes ('Fishes V') developed a 'neck' in the form of a two-bone articulated connection between the body and the 'head region', allowing the latter considerable freedom of movement relative to the body. The thing is that a similar 'neck' also evolved between the 'head part' housing eyes and ears, and the mouth region. Are there then two heads, or is the entire region one head? 

The two necks, usually called the proximal (closest to the body) and distal (farthest from the body) neck, each consist of two long bones with a joint in between. The two 'heads' are the 'sensocranium' and the 'orocranium'. The image above shows a fragment of a painting showing a species of Fishes V with just that arrangement. You cannot see the joints in the necks clearly in these streamlined Fishes, but they are there. Those long neck bones form a big difference from the kind of vertebral columns we are used to, with their string of many small bones. Early Scalates never had a central string of small bones for evolution to play with; instead, they had a 'ladder'. The resulting neck movements look rather like those of a vertebrate arm or leg, with sharp angles, not at all like the curves of a lizard tail or a giraffe or sauropod neck. But that ungainly look need not be a functional handicap; despite the sticklike nature of human arms, baseball and darts players manage to land small objects with incredible precision quite a distance away. Of course, the trick is having a good brain in control.

We now only need to discuss bending of other organs in those necks, such as the oesophagus. An oesophagus relies on peristalsis making it flexible and elastic, so the structure itself should be able to withstand folding for a while. The nerves and arteries in our shoulders and elbows have to withstand bending too and usually do so fine. (Admittedly, if you spend too long in one position local pressure may pinch blood vessels, so people occasionally find that an arm or a leg, or just one nerve, has 'gone to sleep'.) If the oesophagus would be folded, it would probably be incapable of propelling food. If so, the distal neck has to be straightened between bites to allow the animal to swallow which is not a problem and looks interesting. Perhaps a different problem is that the length of the oesophagus may have to vary with neck position. If the oesophagus lies in front of or below the neck bones, as it does in humans, bending the neck backwards and upwards requires the oesophagus to lengthen. It has to be elastic anyway, so some degree of lengthening should not be a problem. 

Click to enlarge; copyright Katrina van Grauw

There is another solution though. In birds, the trachea (windpipe) and oesophagus do not commonly lie in front of the neck vertebrae, but to one side. This is not the exception but the rule, in fact, as shown by this paper. Most often the trachea and oesophagus lie toon the right side, but that can differ between individuals, with recorded examples on the trachea on one side and the oesophagus on the other. If birds bending their generally long necks, the oesophagus does not have to follow the bones. The oesophagus literally cuts corners. 

Click to enlarge; source here

The two images above show this odd anatomy very clearly, with a heron as an example. One is from the excellent work 'The unfeathered bird' by Katrina van Grauw, and the other is from the paper mentioned above. The oesophagus runs almost in a straight line when the neck is curved, which also means that the oesophagus is then much shorter than when the neck is fully extended. It has to be very elastic. The explanation for this arrangement is that the trachea and oesophagus can move so freely because they are not restrained by muscles as is the case in mammals. Some birds can swallow enormous prey (herons again) which also requires that the oesophagus has freedom of movement. 

Click to enlarge; copyright Gert van Dijk

I am revising an older image of a herd of large hexapods thundering into view. To get a better idea of their heads, I sculpted one in Zbrush. 

Click to enlarge; copyright Gert van Dijk

 
Click to enlarge; copyright Gert van Dijk
 

As you can see, I played with a lateral position of the oesophagus. The oesophagus forms a distinct bulge on the left side of the distal neck, cutting corners in bird fashion. The sensocranium sports shields and horns to impress others of its own species. When the animals start bashing one another's heads and necks, the necks should be protected too, so the middle joint of the proximal neck also bears some shields. So here is the somewhat baroque Latifrons augustus ('elevated broad-brow').

Thursday 3 August 2023

A sample of The Book (and a new painting)

It's time for a quick update. As you may know, The Book is ready to find a home with a publisher. Unfortunately, one or two of the publishers I would be very happy with warn aspiring authors away by saying that they pick their own candidates and have plenty of those to choose from, thank you very much. Others say they want submissions on paper, not digital, which might be a way to reduce the number of proposals they receive. If so, good, as perhaps my proposal may then have fewer others to compete with. Anyway, I had a few samples printed on good quality paper. Here is a quick view of the sample of The Book.


Some of you may have spotted that the name on the sample reads 'Nastrarruzzo', not 'Nastrazzurro'. I had to start an official business to market The Book, (and perhaps sell prints too), and wanted to avoid  possible problems with companies with similar names. That's why my firm is called the 'Nastrarruzzo Compagnie'. 

Click to enlarge; copyright Gert van Dijk

While all this is going on, I do work on the occasional new painting. Actually, there are about four in various stages of completion, but that is usual for me. Here is a fragment of one I just completed. The animal is a hexapod arboreal species, a swobbler (it was originally a 'wobbler', but I made a typo while storing the file, and the unintended 's' made the name more interesting, so I kept it. The animal is not entirely serious...

You may be wondering what the things on its back are. Well, hexapod skins vary a lot, and part of their basic integument is a sort of hair, but hair that is flattened, and often with multiple filaments, so it can range from feather-like structures, but decidedly heavier than true feathers, to a fur-like covering. The structure lends itself well to leaf-like excrescences. As hexapods are not at all restricted to the restricted palette of Earth's mammals, there is room for weird and colourful protuberances. 

The fruit is a baignac, of course. Don’t eat them if you are a human.

Sunday 18 June 2023

A work in progress: the pied stickler

It has been a while since I last posted something here. There were multiple reasons for that: the realisation that there are more than enough paintings for The Book lessened my enthusiasm to start new Furaha paintings. An interesting side effect of that is that I started painting a series of paintings completely unrelated to speculative biology, which was refreshing. So much so, in fact, that having finished three such paintings I became eager to do some more Furahan creatures.

Another factor is that the number of views and replies has been fairly low lately. Is a blog like this one too old-fashioned, or perhaps too complex? No longer interesting? Or is it too difficult to leave a reply? I thought so when I wanted to write something on someone else's blog. Ideas and thoughts are welcome.

 

Click to enlarge; copyright Gert van Dijk


Anyway, here is a detail of a work in progress showing a 'pied stickler' (Perfixor artifex). The name means 'cunning impaler'. A part of the accompanying text follows.

Katarzyna Altanero, who devoted her life to the study of hexapod carnivores, described sticklers as ‘prototypical gregarious piluferentic centauraptors’. This statement shows that doctissimus Altanero was one of those people who, once they have learned something, think that people are born with that knowledge already in place. But the cumbersome jargon is correct. 

'Centauraptors’
These animals are obviously hexapods, but they have freed their front legs from all locomotion duties, a principle known on Furaha as ‘centaurism’. Here, the limbs have become weapons.  
Centaurism probably involves very quick evolution. The front limbs, liberated from walking, were free to quickly evolve suitable shapes for their new roles. At the same time the balance and locomotion of the animal changed drastically. The front part of the trunk became shorter and was tilted upwards, while the former middle legs increased in size and moved forwards.  
   These changes must have evolved hand in hand with specialisation to a specific way of catching prey. For instance, predators relying on speed should not carry massive heavy clubs, and those aiming to bring down armoured prey must have adequate weaponry and need only be faster than their prey. Scavenging centauraptors can be slow , allowing some of the heaviest weaponry of all.   

‘Piluferentic’
Centauraptor weapons betray an interesting array of forms. Some are pure clubs, others function only as ‘pointy end’ weapons, and in yet others the limb has more than one purpose. The limb type known as ‘axes’ have a sharp edge on the underside, useful to hack open a carcass, but the same weapon usually has a heavy bulge too, allowing it to double as a club to knock prey off their feet or to bludgeon the prey's head, blinding it.
   The stickler’s weapons are no exception to this ‘Swiss army knife’ approach. While its weapon is primarily shaped like a club, the former foot has become a sharp protrusion that can be swung into action. This sting explains the word ‘piluferens’, meaning 'lance carrying’.   

‘Gregarious’
As the word suggests, sticklers live in groups. In this species’ case, tasks differ between group members, allowing a fairly complex society that must run on advanced cognitive capacity. Do not underestimate sticklers; one may appear to study you with open curiosity, but its pack members may well be behind you, on their way to encircle you. They cannot digest humans but that makes little difference to the human involved.