Dimetrodon's sail

[Bowhead Whale]

it may also have benefits of keeping you warm when you're submerged.  However a sail is not useful if you are an ambush predator nor is it really useful for swimming under water, as it would act like a big, upside down keel creating resistance during lateral movement.

Stargatedalek: I looked at the Ouranosaurus skeleton and it seems to have long spines running the entire length of the back; maybe i'm just not understanding what you mean by 'forward facing'.

The sail is not a problem of ambush when you eat fish: fish do nont necessarily look at what is above water, unless they feed on insects. Spinosaurus skull has many holes on it like sharks and crocodiles. These holes were pressure sensors, like those of those modern animals. That means Spinosaurus ate fish, not land animals. No?

As for talking about Spinosaurus, well, I don't think we can understand the frill of Dimetrodon if we don't compare it with sails of other animals. When we want to understand a feature, we look at other animals with a similar feature. No?

These are not similar features. Spinosaurus had very large broad extensions of its vertebrae. These are broad as they are in bison and rhinoceros because they are attachments for musculature. Dimetrodon and kin have tiny thin shafts extending from the vertebrae, not large segments extending vertically. They are like the sail supporting structures of basilisks and similar lizards.

But the Spinosaur sail is so round shaped... what muscles could it support on the middle of the back? No, there is something else behind it, for sure.

[Bowhead Whale]

bruh i dont care about all these smurfs and terfs i just wanna learn about my favorite animal

What are you talking about? You mean the talk of Spinosaurus and such?

If so, I concur. There is nothing similar about the structures of them and Dimetrodon aside from just being a dorsal structure in general.

no i mean dimetrodon haha its my faaavourite
didnt see we were back on track i was still on page one and didnt know there was a page two of this discussion where everyone was back on subject

It's OK to have a favorite! 

[stargatedalek]

it may also have benefits of keeping you warm when you're submerged.  However a sail is not useful if you are an ambush predator nor is it really useful for swimming under water, as it would act like a big, upside down keel creating resistance during lateral movement.

Stargatedalek: I looked at the Ouranosaurus skeleton and it seems to have long spines running the entire length of the back; maybe i'm just not understanding what you mean by 'forward facing'.

The sail is not a problem of ambush when you eat fish: fish do nont necessarily look at what is above water, unless they feed on insects. Spinosaurus skull has many holes on it like sharks and crocodiles. These holes were pressure sensors, like those of those modern animals. That means Spinosaurus ate fish, not land animals. No?

As for talking about Spinosaurus, well, I don't think we can understand the frill of Dimetrodon if we don't compare it with sails of other animals. When we want to understand a feature, we look at other animals with a similar feature. No?

These are not similar features. Spinosaurus had very large broad extensions of its vertebrae. These are broad as they are in bison and rhinoceros because they are attachments for musculature. Dimetrodon and kin have tiny thin shafts extending from the vertebrae, not large segments extending vertically. They are like the sail supporting structures of basilisks and similar lizards.

But the Spinosaur sail is so round shaped... what muscles could it support on the middle of the back? No, there is something else behind it, for sure.

Have you looked at rhinoceros or bison skeletons for reference?



It's plenty round, if not more round, and extends pretty far along the back. The musculature these structures support are somewhat sprawling, the intention is that they provide surface area to just lay out as many muscles as possible stretching out horizontally along the whole length of the back.

[Reuben03]

bruh i dont care about all these smurfs and terfs i just wanna learn about my favorite animal

What are you talking about? You mean the talk of Spinosaurus and such?

If so, I concur. There is nothing similar about the structures of them and Dimetrodon aside from just being a dorsal structure in general.

no i mean dimetrodon haha its my faaavourite
didnt see we were back on track i was still on page one and didnt know there was a page two of this discussion where everyone was back on subject

It's OK to have a favorite! 

sure is! haha dimetrodon is just so so beautiful, something about it just draws me to it so much

[Bowhead Whale]

it may also have benefits of keeping you warm when you're submerged.  However a sail is not useful if you are an ambush predator nor is it really useful for swimming under water, as it would act like a big, upside down keel creating resistance during lateral movement.

Stargatedalek: I looked at the Ouranosaurus skeleton and it seems to have long spines running the entire length of the back; maybe i'm just not understanding what you mean by 'forward facing'.

The sail is not a problem of ambush when you eat fish: fish do nont necessarily look at what is above water, unless they feed on insects. Spinosaurus skull has many holes on it like sharks and crocodiles. These holes were pressure sensors, like those of those modern animals. That means Spinosaurus ate fish, not land animals. No?

As for talking about Spinosaurus, well, I don't think we can understand the frill of Dimetrodon if we don't compare it with sails of other animals. When we want to understand a feature, we look at other animals with a similar feature. No?

These are not similar features. Spinosaurus had very large broad extensions of its vertebrae. These are broad as they are in bison and rhinoceros because they are attachments for musculature. Dimetrodon and kin have tiny thin shafts extending from the vertebrae, not large segments extending vertically. They are like the sail supporting structures of basilisks and similar lizards.

But the Spinosaur sail is so round shaped... what muscles could it support on the middle of the back? No, there is something else behind it, for sure.

Have you looked at rhinoceros or bison skeletons for reference?



It's plenty round, if not more round, and extends pretty far along the back. The musculature these structures support are somewhat sprawling, the intention is that they provide surface area to just lay out as many muscles as possible stretching out horizontally along the whole length of the back.

Bison and rhino skelettons show the roundness of the spines at the level of the SHOULDERS. The Spinosaurus' skeletton's spines show the roundness of the spines at the level of the MIDDLE OF THE BACK. If they were for muscle attachment, we would see the roundness at the shoulders and/ or at the hips. Not the middle of the back.

[Bowhead Whale]

bruh i dont care about all these smurfs and terfs i just wanna learn about my favorite animal

What are you talking about? You mean the talk of Spinosaurus and such?

If so, I concur. There is nothing similar about the structures of them and Dimetrodon aside from just being a dorsal structure in general.

no i mean dimetrodon haha its my faaavourite
didnt see we were back on track i was still on page one and didnt know there was a page two of this discussion where everyone was back on subject

It's OK to have a favorite! 

sure is! haha dimetrodon is just so so beautiful, something about it just draws me to it so much

Reptiles and Amphibians of the Permian should indeed be more shown in books and as toys than they are today. Edaphosaurus is quite an interesting species as well. And it has a sail just like the Dimetrodon! Even if it is more oval than its carnivorous counterpart. And what abouth Tanystropheus! How can we  remain indifferent in front of this extra-long, yet stiff neck! Just so bizarre!

[Reuben03]

bruh i dont care about all these smurfs and terfs i just wanna learn about my favorite animal

What are you talking about? You mean the talk of Spinosaurus and such?

If so, I concur. There is nothing similar about the structures of them and Dimetrodon aside from just being a dorsal structure in general.

no i mean dimetrodon haha its my faaavourite
didnt see we were back on track i was still on page one and didnt know there was a page two of this discussion where everyone was back on subject

It's OK to have a favorite! 

sure is! haha dimetrodon is just so so beautiful, something about it just draws me to it so much

Reptiles and Amphibians of the Permian should indeed be more shown in books and as toys than they are today. Edaphosaurus is quite an interesting species as well. And it has a sail just like the Dimetrodon! Even if it is more oval than its carnivorous counterpart. And what abouth Tanystropheus! How can we  remain indifferent in front of this extra-long, yet stiff neck! Just so bizarre!

yes!! i would like a cuddly dimetrodon teutonis plush

[stargatedalek]

it may also have benefits of keeping you warm when you're submerged.  However a sail is not useful if you are an ambush predator nor is it really useful for swimming under water, as it would act like a big, upside down keel creating resistance during lateral movement.

Stargatedalek: I looked at the Ouranosaurus skeleton and it seems to have long spines running the entire length of the back; maybe i'm just not understanding what you mean by 'forward facing'.

The sail is not a problem of ambush when you eat fish: fish do nont necessarily look at what is above water, unless they feed on insects. Spinosaurus skull has many holes on it like sharks and crocodiles. These holes were pressure sensors, like those of those modern animals. That means Spinosaurus ate fish, not land animals. No?

As for talking about Spinosaurus, well, I don't think we can understand the frill of Dimetrodon if we don't compare it with sails of other animals. When we want to understand a feature, we look at other animals with a similar feature. No?

These are not similar features. Spinosaurus had very large broad extensions of its vertebrae. These are broad as they are in bison and rhinoceros because they are attachments for musculature. Dimetrodon and kin have tiny thin shafts extending from the vertebrae, not large segments extending vertically. They are like the sail supporting structures of basilisks and similar lizards.

But the Spinosaur sail is so round shaped... what muscles could it support on the middle of the back? No, there is something else behind it, for sure.

Have you looked at rhinoceros or bison skeletons for reference?



It's plenty round, if not more round, and extends pretty far along the back. The musculature these structures support are somewhat sprawling, the intention is that they provide surface area to just lay out as many muscles as possible stretching out horizontally along the whole length of the back.

Bison and rhino skelettons show the roundness of the spines at the level of the SHOULDERS. The Spinosaurus' skeletton's spines show the roundness of the spines at the level of the MIDDLE OF THE BACK. If they were for muscle attachment, we would see the roundness at the shoulders and/ or at the hips. Not the middle of the back.

Have you seen a Spinosaurus skeleton lately? They are round over the shoulders and hips.

Look at the bison skeleton again, then back at these. The bisons spines are longer all the way into the middle of the back, despite being largest around the shoulders. Spinosaurus has large muscle attachments at the shoulders and at the hips, the high spines in the middle are also there on the bison just less obvious because it doesn't have higher sections on both ends.

[ITdactyl]

Tall neural spines in bison and camel support the neck raising muscles (as well as serve as the base for the fat storing humps - because mammals?). I can see the same (just the neck raisin part) being true for Spinosaurus given its long neck and proposed hunting style.  Height of the Neural spines seem to peak near the center of gravity; near the front legs for the mammals since they're front-heavy quadrupeds, and further back for Spinosaurus the biped.

-back on topic-
Dimetrodon neural spines to me look more similar to Spinosaurus' caudal spines. Ibrahim (2020) proposes that the base of Spinosaurus' tail spines serve as anchor points for the muscles that run along the tail, giving it more power despite being less muscled than a crocodile's.  Maybe it's a similar situation for Dimetrodon, and the sail gives it a more robust back (epaxial muscles covering and attaching to the base of the sail). Arm waving here, but could that have allowed it to be able to run down its prey while still being cold blooded (or not fully endothermic)? I mean, if the epaxial muscles have more attachment points compared to a regular spine, then I expect a substantial effect on its locomotive abilities.

As for the display features of Dimetrodon sails, well the neat slope of D.grandis spines seem to allow full webbing. Those of D.gigashomogenes have spines that bend at the tips, so probably not fully webbed. Those differences suggest a species recognition function for the sails (that is, if some species did coexist)

Oh, here's my reference for my arm waving about epaxials:
https://journals.biologists.com/jeb/article/213/9/1490/10266/Function-of-the-epaxial-muscles-in-walking

[Bowhead Whale]

But why having such muscle attaches if the Spinosaurus had such little limbs? Because its limbs are proportionnally a lot shorter in the body of the Spinosaurus than those of the bison. Yet, the spines of the bison are a lot shorter than those of the Spinosaurus. So, there is still a contradiction to my eyes, here. It's a pity those animals left only skeletons for us to look at. Because some of their features leave sometimes more questions than answers...

[Bowhead Whale]

bruh i dont care about all these smurfs and terfs i just wanna learn about my favorite animal

What are you talking about? You mean the talk of Spinosaurus and such?

If so, I concur. There is nothing similar about the structures of them and Dimetrodon aside from just being a dorsal structure in general.

no i mean dimetrodon haha its my faaavourite
didnt see we were back on track i was still on page one and didnt know there was a page two of this discussion where everyone was back on subject

It's OK to have a favorite! 

sure is! haha dimetrodon is just so so beautiful, something about it just draws me to it so much

Reptiles and Amphibians of the Permian should indeed be more shown in books and as toys than they are today. Edaphosaurus is quite an interesting species as well. And it has a sail just like the Dimetrodon! Even if it is more oval than its carnivorous counterpart. And what abouth Tanystropheus! How can we  remain indifferent in front of this extra-long, yet stiff neck! Just so bizarre!

yes!! i would like a cuddly dimetrodon teutonis plush

I do have a cuddly dimetrodon plushie at home. Would you like to see it?

[stargatedalek]

But why having such muscle attaches if the Spinosaurus had such little limbs? Because its limbs are proportionnally a lot shorter in the body of the Spinosaurus than those of the bison. Yet, the spines of the bison are a lot shorter than those of the Spinosaurus. So, there is still a contradiction to my eyes, here. It's a pity those animals left only skeletons for us to look at. Because some of their features leave sometimes more questions than answers...

Because those muscles are not related to the limbs. The raised section on the shoulders is for raising a large head and neck. Bison have this to support their extremely large and robust skulls and horns, which are even more dramatic on some extinct bison. Spinosaurus had them to support its extremely long and heavy neck. Why don't we see these structures in sauropods then? Well, we do in a few of them, but mostly we don't because their necks aren't as flexible as Spinosaurus, Spinosaurus needs to have the neck held up, not stiffened, in order to maintain full movement. Spinosaurus also has one over the hips to do the same (and more) for its tail.

Bison (and rhinoceros) humps also do not have fat stores, they are entirely muscle, as would have been the case in Spinosaurus and Ouranosaurus. Camels don't have large spines like these to support their humps.

[Bowhead Whale]

But why having such muscle attaches if the Spinosaurus had such little limbs? Because its limbs are proportionnally a lot shorter in the body of the Spinosaurus than those of the bison. Yet, the spines of the bison are a lot shorter than those of the Spinosaurus. So, there is still a contradiction to my eyes, here. It's a pity those animals left only skeletons for us to look at. Because some of their features leave sometimes more questions than answers...

Because those muscles are not related to the limbs. The raised section on the shoulders is for raising a large head and neck. Bison have this to support their extremely large and robust skulls and horns, which are even more dramatic on some extinct bison. Spinosaurus had them to support its extremely long and heavy neck. Why don't we see these structures in sauropods then? Well, we do in a few of them, but mostly we don't because their necks aren't as flexible as Spinosaurus, Spinosaurus needs to have the neck held up, not stiffened, in order to maintain full movement. Spinosaurus also has one over the hips to do the same (and more) for its tail.

Bison (and rhinoceros) humps also do not have fat stores, they are entirely muscle, as would have been the case in Spinosaurus and Ouranosaurus. Camels don't have large spines like these to support their humps.

Then why didn't the Baryonyx have similar spines while it has a similar head and similar way of feeding?

[stargatedalek]

But why having such muscle attaches if the Spinosaurus had such little limbs? Because its limbs are proportionnally a lot shorter in the body of the Spinosaurus than those of the bison. Yet, the spines of the bison are a lot shorter than those of the Spinosaurus. So, there is still a contradiction to my eyes, here. It's a pity those animals left only skeletons for us to look at. Because some of their features leave sometimes more questions than answers...

Because those muscles are not related to the limbs. The raised section on the shoulders is for raising a large head and neck. Bison have this to support their extremely large and robust skulls and horns, which are even more dramatic on some extinct bison. Spinosaurus had them to support its extremely long and heavy neck. Why don't we see these structures in sauropods then? Well, we do in a few of them, but mostly we don't because their necks aren't as flexible as Spinosaurus, Spinosaurus needs to have the neck held up, not stiffened, in order to maintain full movement. Spinosaurus also has one over the hips to do the same (and more) for its tail.

Bison (and rhinoceros) humps also do not have fat stores, they are entirely muscle, as would have been the case in Spinosaurus and Ouranosaurus. Camels don't have large spines like these to support their humps.

Then why didn't the Baryonyx have similar spines while it has a similar head and similar way of feeding?

Because it was much smaller with a shorter neck. Spinosaurus has a longer neck, meaning more weight, and is a good 5 times the size, meaning more weight.

Also, they did not likely have similar ways of feeding. Spinosaurus is adapted to pursue prey in the water, whether that was floating, diving, or a mix of both. Baryonyx however shows adaptations of a shoreline generalist.

[Bowhead Whale]

And why did Ouranosaurus have similar spines? It didn't have horns, so it did not charge like a bison. It ate plants, so it did not pursue preys in the water. But it had a similar spine. And it was found in the same areas as Spinosaurus. How can we be sure those spines didn't have a link with the climate instead of way of living?

[stargatedalek]

And why did Ouranosaurus have similar spines? It didn't have horns, so it did not charge like a bison. It ate plants, so it did not pursue preys in the water. But it had a similar spine. And it was found in the same areas as Spinosaurus. How can we be sure those spines didn't have a link with the climate instead of way of living?

Bison don't have the hump because they charge, they have it because their heads are heavy. It just happens that they are heavy in part because of the bisons horns. It's also extremely untrue that only animals with horns charge, plenty of large herbivores will charge would-be predators or even competitors, horns just happen to have already been the norm among grazing mammals.

Even if it was climate related, the biggest impact there is surface area. Not only is the surface area going to be higher on a thickened muscular structure anyway, but these are very extreme adaptations compared to ones animals normally adapt for temperature control.

Even in the best possible case for a sail, where we are assuming these structure are climate related for temperature regulation, a large area of musculature to better distribute loads would have helped to prevent overheating a lot better than a sail like structure, which again, the anatomy itself does not support to begin with.

Most ornithopods had vertebrae like this, thick and broad like rectangles. Just more of a ridge than a muscular hump (though all of these, even bison, are more like a ridge than the humps of camels and such). They aren't even that much taller in Ouranosaurus along the back, only the shoulders are unusual for the group at all.

Depict Ouranosaurus with the additional neck muscles we now know ornithpopods had, like this Parasaurolophus for example, and those spines look a lot clearer in how they would have connected to the neck.




As for why Ouranosaurus had them, there are a bunch of potential reasons. Perhaps it was feeding on particularly tough plant materials that it was for some reason needing to uproot them, or perhaps it was reaching underwater and needing to pull them back hard to rip them free from the bottom. And of course, just because these structures were supporting muscles, doesn't mean their shape and extent couldn't have been further influenced or exaggerated by selective pressure like display. Just because they originally had a practical function, and at least in Spinosaurus still did, doesn't mean they couldn't have been further exaggerated beyond what the animal technically needed.

It's easy to jump to conclusions since Spinosaurus and Ouranosaurus have been found in the same areas*, but think of the many other animals known from the same formations. Reptiles, amphibians, dozens of other dinosaurs alone. Two out of an awful lot of animals with vaguely similar adaptations is not particularly unusual.

*Edit: Spinosaurus and Ouranosaurus are not found in any of the same formations.

To circle back around, compare to Dimetrodon, which had a sail, and the differences between the structures are very apparent. Dimetrodon's are completely different in shape, and additionally are not an extension of a pre-existing muscular ridge along the back, as they are in dinosaurs, but a "new" structure emerging from the back directly in this shape.

[Bowhead Whale]

And why did Ouranosaurus have similar spines? It didn't have horns, so it did not charge like a bison. It ate plants, so it did not pursue preys in the water. But it had a similar spine. And it was found in the same areas as Spinosaurus. How can we be sure those spines didn't have a link with the climate instead of way of living?

Bison don't have the hump because they charge, they have it because their heads are heavy. It just happens that they are heavy in part because of the bisons horns. It's also extremely untrue that only animals with horns charge, plenty of large herbivores will charge would-be predators or even competitors, horns just happen to have already been the norm among grazing mammals.

Even if it was climate related, the biggest impact there is surface area. Not only is the surface area going to be higher on a thickened muscular structure anyway, but these are very extreme adaptations compared to ones animals normally adapt for temperature control.

Even in the best possible case for a sail, where we are assuming these structure are climate related for temperature regulation, a large area of musculature to better distribute loads would have helped to prevent overheating a lot better than a sail like structure, which again, the anatomy itself does not support to begin with.

Most ornithopods had vertebrae like this, thick and broad like rectangles. Just more of a ridge than a muscular hump (though all of these, even bison, are more like a ridge than the humps of camels and such). They aren't even that much taller in Ouranosaurus along the back, only the shoulders are unusual for the group at all.

Depict Ouranosaurus with the additional neck muscles we now know ornithpopods had, like this Parasaurolophus for example, and those spines look a lot clearer in how they would have connected to the neck.




As for why Ouranosaurus had them, there are a bunch of potential reasons. Perhaps it was feeding on particularly tough plant materials that it was for some reason needing to uproot them, or perhaps it was reaching underwater and needing to pull them back hard to rip them free from the bottom. And of course, just because these structures were supporting muscles, doesn't mean their shape and extent couldn't have been further influenced or exaggerated by selective pressure like display. Just because they originally had a practical function, and at least in Spinosaurus still did, doesn't mean they couldn't have been further exaggerated beyond what the animal technically needed.

It's easy to jump to conclusions since Spinosaurus and Ouranosaurus have been found in the same areas*, but think of the many other animals known from the same formations. Reptiles, amphibians, dozens of other dinosaurs alone. Two out of an awful lot of animals with vaguely similar adaptations is not particularly unusual.

*Edit: Spinosaurus and Ouranosaurus are not found in any of the same formations.

To circle back around, compare to Dimetrodon, which had a sail, and the differences between the structures are very apparent. Dimetrodon's are completely different in shape, and additionally are not an extension of a pre-existing muscular ridge along the back, as they are in dinosaurs, but a "new" structure emerging from the back directly in this shape.

"Jumping on conclusions"... that is what you think I did? The head of the Ouranosaurus, if it had to unroot plants like you say, would be a lot larger than that! Elephants have a big head, horses have a rather large head, hippopotamuses have an enormous head, giraffes have an extraordinarily long neck and this is why they need big neck muscles and long spines! Large muscles supporting a small, delicate head and a relatively short neck does not make much sense to me. In that case, ceratopsids would have enormous spines just to attach muscles to lift that enormous head of theirs. But they don't have those spines. This is why I thought Ouranosaurus (and Spinosaurus) had a sail instead of huge neck muscles. In other words, I had reflexions a little longer than you think, I didn't "jump" on conclusions! Besides, either those dinosaurs have a sail or large muscles have nothing to do with what I would want or not; in either case, it wouldn't change much for me. I just try to figure what they looked like, just like you do, with the remains we have in front of us. That's all.

[stargatedalek]

"Jumping on conclusions"... that is what you think I did? The head of the Ouranosaurus, if it had to unroot plants like you say, would be a lot larger than that! Elephants have a big head, horses have a rather large head, hippopotamuses have an enormous head, giraffes have an extraordinarily long neck and this is why they need big neck muscles and long spines! Large muscles supporting a small, delicate head and a relatively short neck does not make much sense to me. In that case, ceratopsids would have enormous spines just to attach muscles to lift that enormous head of theirs. But they don't have those spines. This is why I thought Ouranosaurus (and Spinosaurus) had a sail instead of huge neck muscles. In other words, I had reflexions a little longer than you think, I didn't "jump" on conclusions! Besides, either those dinosaurs have a sail or large muscles have nothing to do with what I would want or not; in either case, it wouldn't change much for me. I just try to figure what they looked like, just like you do, with the remains we have in front of us. That's all.

I said "It's easy to jump to conclusions since Spinosaurus and Ouranosaurus have been found in the same areas". This was in reference to your claim that these structures must have been environment related because two animals in the same area both had them. A claim that ultimately didn't even pan out, Spinosaurus and Ouranosaurus are not found in the same areas. It's a very common figure of speech and I'm sorry it bothered you so much but please stop lashing out over that.

Ouranosaurus doesn't have a small delicate head, it's pretty bulky actually. It has a large broad bill and an elongated skull relative to most large ornithopods. The idea that it was hoovering up vegetation, or at least eating in a different way from the browsing of other large ornithopods, and so could have benefited from stronger neck muscles matches well with the skull.

Ceratopsians do have vertebrae designed for additional muscle support. They run the full length of the back and while they look small relative to Parasaurolophus let alone Ouranosaurus, they are very definitely serving as muscle anchoring points. Ceratopsian necks are also much thicker and sturdier, not to mention considerably shorter, making it easier for them to support weight without additional assistance. Plus they have much bulkier and more compact shoulders and forelimbs to help support and distribute that weight.

Additionally, ceratopsians feed by plucking and chewing with very powerful jaw muscles and their sharp beaks. So not very applicable to ornithopods.

[Bowhead Whale]

The Ouranosaurus head may be big like that, but look at it compared to the body: it is pretty small. Way too small to necessitate long spines for muscle anchors for it! Horse have a much bigger head compared to their body and they don't have exaggeratedly long spines to have muscles to lift it. Those spines look way too exaggerated for the head just to be a purpose to attach muscles. It's like if Tyrannosaurus had big shoulder muscles to lift its tiny arms. To me, it looks like that. So, to me, it MUST have had another purpose. If not, there is too much of a contradiction there. No?

[stargatedalek]

The Ouranosaurus head may be big like that, but look at it compared to the body: it is pretty small. Way too small to necessitate long spines for muscle anchors for it! Horse have a much bigger head compared to their body and they don't have exaggeratedly long spines to have muscles to lift it. Those spines look way too exaggerated for the head just to be a purpose to attach muscles. It's like if Tyrannosaurus had big shoulder muscles to lift its tiny arms. To me, it looks like that. So, to me, it MUST have had another purpose. If not, there is too much of a contradiction there. No?

There is no contradiction. Animals have muscles because they use them, those muscles don't have to be literally supporting the weight of the head, they could also facilitate behaviours such as methods of feeding.