Animal dorsal view visuals.

[Supercommunist]

Most size comparisons are from the side, which makes sense but a lot of times the true sense of size is lost if you only look at an animal from that angle.

I am not going to lie, I was bummed when I saw how thin ceratosaurus was from a bird's eye perspective. I thought it was bulky like a rex, oh well, still one of my favorites.





www.deviantart.com/randomdinos/art/Various-GDIs-for-assorted-dinosaur-taxa-661969607



www.researchgate.net/publication/292157963_A_re-evaluation_of_several_character_states_in_non-coelurosaurian_Tetanurae_Dinosauria_Theropoda_with_implications_for_phylogeny_of_basal_tetanurans/figures?lo=1







www.researchgate.net/figure/Morphology-and-arrangement-of-rauisuchian-osteoderms-A-B-Skeletal-reconstruction-of_fig1_259089477

[Infinity Blade]

Here's a post I made on another thread with just this.

May 8, 2022 5:30:31 GMT 5 Infinity Blade said:

Not so much a size comparison, but some top views of some animals.

Here's the Triceratops specimen named Dirk (total body length just over 6 meters). It was a subadult, yet look at how massive that ribcage is (source->).




Here are top views of different elephant species, extant and extinct (Larramendi et al., 2017).

This is what a lion looks like in top view, when you strip away the fur.


(lower image by Maria Panfilova->)

This is a dorsal view of a grizzly bear, both with musculature only and with skin (by Nicolas Morel->).

[Supercommunist]

It's interesting how narrow the lion is despite they fact that they are obviously powerful animals.

Wildebeest and zebras have far bulkier torsos but studies have shown that lions are about 20 percent more powerful than similar sized zebras.





It's a safe bet that narrow chested theropods dinosaurs like ceratosaurus were probably weaker than bruisers like tyrannosaurus but they may still have been more powerful than similar sized herbivores with thick chests.



bioone.org/journals/journal-of-vertebrate-paleontology/volume-39/issue-5/02724634.2019.1693396/Postcranial-Anatomy-and-Osteoderm-Histology-of-Riojasuchus-tenuisceps-and-a/10.1080/02724634.2019.1693396.short

[Infinity Blade]

Yeah, if I had to make a comparison here, I'd say Ceratosaurus is like a lion, while T. rex is like a brown bear. I always thought that even if Ceratosaurus was narrow-chested, that doesn't necessarily mean it was a weak animal, for the very reason you mention above.

[Supercommunist]

I wonder what's up with all the extra vertical chest depth? Maybe an adaptation for increasing strengh while also keeping it streamlined?

[theropod]

Sept 2, 2023 4:54:26 GMT 5 Supercommunist said:

It's interesting how narrow the lion is despite they fact that they are obviously powerful animals.

Wildebeest and zebras have far bulkier torsos but studies have shown that lions are about 20 percent more powerful than similar sized zebras.

Well, why would one expect the bulk of the torso to have much relevance for how powerful an animal is (at similar overall mass)?

Those torsos are mainly composed of internal organs that do not contribute to strength, and are also not very flexible, especially when they are very bulky.

Even if the wider torso were in some way related to thicker (?back-) muscles, which I think isn’t necessarily the case, this likely wouldn’t contribute to actual usable strength, as the range of motion within the torso is fairly limited, especially if that torso is very compact. A lion’s torso may be much more elongated, but its axial musculature may well actually be more developed than a zebra’s or wildebeest’s, precisely because the body is longer and more flexible, and hence doesn’t have as much passive rigidity and support, meaning it would require more musculature to actively support it.

Of course it depends on how we even define or attempt to quantify how "powerful" an animal is, which is very tricky to do anyway (I’d be curious as to how someone quantified that a lion is 20% "more powerful" than a zebra too).

If we’re thinking of a shoving, ramming or wrestling contest, simple mass is of course going to be very helpful, and a more robust body shape is a way of achieving that (though not at mass parity, obviously), even if the amount of musculature were to stay the same. But if we’re talking about the actual muscular power an animal can bring to bear in various situations, and talking about mass parity, what needs to be looked at are the actual muscles of the animal, not how wide it’s ribcage or gut is.
The general reasoning for why people think more "robust" animals are stronger is that all else being equal, a shorter, thicker muscle of the same mass will have the larger cross-section, and thus be able to produce a greater force (but not necessarily more power, power being force times velocity, and thus related to the power stroke and speed of the muscle contraction, the former being in turn lower for a shorter muscle).

But really, this ignores the aspects explained above; most of the bulk of most animals is in the torso, and most of the time people focus heavily on the torso when evaluating how "robust" they perceive an animal to be, but the torso will usually contribute very little to functional muscle power (as already explained). In fact if it is disproportionately the torso that is more robust, it might mean that when actually compared at mass parity, many other parts (and muscles) of the more elongated animal are going to be larger, as less of it is going to be torso. It also ignores that while a more elongate animal may have longer, thinner muscles for the same mass, it also might have longer muscle moment arms, compensating for their lower cross-sectional areas.

I think that honestly a lot of the popular "more robust animals are more powerful" trope stems not from biomechanical reality, but from tending to compare animals at similar linear dimensions, in which case of course you aren’t actually comparing similar-sized animals, you are comparing a more robust animal that is also much larger overall to less robust animal that is also generally smaller. Like comparing a jaguar to a leopard; of course the former is certainly more powerful, but that’s not just because it is more robust, but mainly because it is simply larger (by mass), even if it isn’t longer or taller.
I could envision that if people were more accustomed to seeing visual comparisons of animals of differing levels of robusticity at actual mass parity (a 200 kg bear and a 200 kg tiger, a 90 kg jaguar and a 90 kg leopard, a 9 t Giganotosaurus and a 9 ton T. rex etc.), they would come to rather different conclusions regarding their "power levels". As it is, of course this is not what we are commonly being shown. Real-life jaguars are much bigger than real life leopards, real-life brown bears are much bigger than real-life tigers, and while real-life Giganotosaurus wasn’t smaller than T. rex at all, the only skeleton of Giganotosaurus is certainly considerably smaller than the two very large T. rex skeletons it is commonly compared to.

What’s likely much more important than the respective width of the chest (which isn’t really of much use when it comes to applying force) between lions and ungulates is that a lion has very different limb morphology from an ungulate. I wouldn’t say its limbs are necessarily more powerful or stronger overall, but it can definitely use them in more versatile ways due to greater dexterity and more evenly distributed limb musculature. On the other hand, my guess would be that a zebra’s kick is actually much stronger than a lion’s (kick or, for a more realistic equivalent, pawswipe), so again, this depends on our standard of comparison. Is the lion better at grappling? Of course. Is there something about its morphology that makes it inherently more powerful or stronger than a zebra? Likely not, its morphology is just adapted to allow it to apply what strength it has in ways that are perhaps more useful to a direct confrontation, and thus it gets perceived as stronger.

Sept 2, 2023 7:39:28 GMT 5 Supercommunist said:

I wonder what's up with all the extra vertical chest depth? Maybe an adaptation for increasing strengh while also keeping it streamlined?

I mean viscera and other internal organs need to go somewhere…
Also there’s been the suggestion in the literature that Ceratosaurus may have been a good swimmer or even specialized for life in fluvial environments (as opposed to Allosaurus being more specialized for arid environments), in which case it is plausible that a laterally flattened body could have been useful as an adaptation for swimming (though I will readily admit that that’s not necessarily something we see in confirmed semi-aquatic animals). Alternatively, perhaps a very narrow body shape could have been useful for locomotion in thickly forested areas by improving its ability to fit between (vertical) obstacles, but also its lateral spine flexibility (although with the downside that it likely means higher rotational inertia for a given body mass…which might not be so important seeing how no large theropod is likely to have been capable of quick turns to begin with).

But seeing how this is all based on Greg Paul’s skeletons, and how they are sometimes known to unreasonably reduce certain dimensions (to this day his published skeletal of Sue is only 10.5 or at best 11 m in axial length, when literally everyone else agrees it should be 12.3-12.4 m) as well as to commonly make animals much more slender than other people’s reconstructions, and seeing how there are rather considerable morphological differences between different Ceratosaurus specimens, it would be interesting to get some independent confirmation of this. The caudal cross-sections in Madsen (1976) do suggest Ceratosaurus was narrower in build compared to Allosaurus, but it’s unclear which specimen this is based on.

Further complicating this, it seems that very little of the ribcage of Ceratosaurus has ever been found to begin with:

Madsen and Welles 2000 said:

Only five isolated ribs of Ceratosarus have been
recovered from the C-LDQ, three dorsal and two cervical.
The cervical ribs UUVP 2172 and 6520 (plate 19) are
incomplete, but were readily identified by comparison with
the sixth cervical vertebra, UUVP 6964 (plate 15), which
retained part of the right rib.
The three dorsal ribs, UUVP 548, UUVP 316, and
UUVP 610 are incomplete, but UUVP 548 is the best ex-
ample measuring 846 mm in length and 152 mm across the
proximal end. These elements are long, relatively heavy,
and only slightly bowed along the proximal third of their
length. Their configuration suggests a slab-sided body cav-
ity for Ceratosaurus.
A common character of these few ribs, cervical and
dorsal, is a pneumatic cavity (plate 19).

In the type of C. nasicornis preserves only a single one according to Gilmore (1920).
So the evidence for the "slab-sided" built in Ceratosaurus seems to literally be this one sentence from Madsen and Welles based on three (?incomplete) thoracic ribs (preserved in isolation). Hence while I don’t necessarily disagree with the evidence for a fairly narrow body shape in Ceratosaurus, I think the error margins are rather large, and it’s also unclear to which extent this can be generalized to all specimens/if it might have been ontogenetically variable, which I think is important to acknowledge.

So I think my bottom line is that just like only looking at lateral views can be misleading, taking any skeletal or comparison at face value without questioning the underlying evidence or assumptions can be as well.
---
Gilmore, C.W. 1920. Osteology of the carnivorous Dinosauria in the United States National museum: with special reference to the genera Antrodemus (Allosaurus) and Ceratosaurus. US Government printing office, Washiington DC.
Madsen, J.H. 1976. Allosaurus fragilis: a revised osteology. Utah Geological and Mining Survey Bulletin 109: 1–163.
Madsen, J.H. and Welles, S.P. 2000. Ceratosaurus (Dinosauria, Theropoda): a revised osteology. Utah Geological Survey Miscellaneous Publications 00–2.
www.theropoddatabase.com/Ceratosauria.htm#Ceratosaurusnasicornis

[Supercommunist]

Well, why would one expect the bulk of the torso to have much relevance for how powerful an animal is (at similar overall mass)?

Those torsos are mainly composed of internal organs that do not contribute to strength, and are also not very flexible, especially when they are very bulky.[/quote]

Generally speaking, bulkier and robust animals tend to be stronger than more gracile animals. Buffalos appear more powerful than similar sized elands, boars appear more powerful than deer at parity, humans with broad muscular chest tend to be stronger than humans with average chests. Smilodon are considerably bulkier than extant cats and most likely were more powerful wrestlers.

Of course it depends on how we even define or attempt to quantify how "powerful" an animal is, which is very tricky to do anyway (I’d be curious as to how someone quantified that a lion is 20% "more powerful" than a zebra too).

It's based on a study.

We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator–prey pair, the predators had 20% higher muscle fibre power than prey,

www.nature.com/articles/nature25479

I think that honestly a lot of the popular "more robust animals are more powerful" trope stems not from biomechanical reality, but from tending to compare animals at similar linear dimensions, in which case of course you aren’t actually comparing similar-sized animals, you are comparing a more robust animal that is also much larger overall to less robust animal that is also generally smaller. Like comparing a jaguar to a leopard; of course the former is certainly more powerful, but that’s not just because it is more robust, but mainly because it is simply larger (by mass), even if it isn’t longer or taller.

In a lot of cases people do compare similar massed creatures. Cheetahs for instance are roughly the same mass as leopards and seem considerably weaker.

I mean viscera and other internal organs need to go somewhere…

Sure, but ceratosaurus seems to have a lot more vertical chest depth than most theropods. Dilophosaurus, for instance, also has a narrow torso but doesn't appear to have as much vertical depth as a ceratosaurus.

But seeing how this is all based on Greg Paul’s skeletons, and how they are sometimes known to unreasonably reduce certain dimensions (to this day his published skeletal of Sue is only 10.5 or at best 11 m in axial length, when literally everyone else agrees it should be 12.3-12.4 m) as well as to commonly make animals much more slender than other people’s reconstructions, and seeing how there are rather considerable morphological differences between different Ceratosaurus specimens, it would be interesting to get some independent confirmation of this. The caudal cross-sections in Madsen (1976) do suggest Ceratosaurus was narrower in build compared to Allosaurus, but it’s unclear which specimen this is based on. Perhaps it will turn out that large, adult Ceratosaurus were broader-bodied than Paul’s reconstruction suggests.

Thanks for the info. Unfortunately, I never been able to memorize which people have reliable reconstructions are which ones don't.



www.deviantart.com/mithoskuu/art/Utahraptor-ostrommaysorum-skeletal-676822799











Not sure if this comparsion is accurate but the size difference is kind of amusing:



www.deviantart.com/triceratopshorridus/art/Utahraptor-vs-Giganotosaurus-841718048

[theropod]

Sept 6, 2023 22:44:12 GMT 5 Supercommunist said:

Generally speaking, bulkier and robust animals tend to be stronger than more gracile animals. Buffalos appear more powerful than similar sized elands, boars appear more powerful than deer at parity, humans with broad muscular chest tend to be stronger than humans with average chests. Smilodon are considerably bulkier than extant cats and most likely were more powerful wrestlers.

"Appear stronger" seems rather like circular reasoning. As I acknowledged, more robust animals do indeed appear to be stronger to most people, but that doesn’t necessarily mean they actually are. If there is a quantitative comparison between the strength of a 1 ton eland and a 1 ton buffalo, I would be very interested in seeing it, as well as what kind of standard for comparing the overall strength of these animals someone might come up with. Clearly these two are not going to wrestle one another (and neither would a boar and deer for that matter).
A shoving match then? Hmm maybe, but this could go either way. Given that both have similarly suitable equipment to actually shove with, a taller, more elongated animal has the advantage of height giving it better leverage and the ability to push down on its opponent, while the shorter animal has the advantage of a lower center of gravity, giving it better stability, but these are also not directly related to strength. If both are the same mass, then it is entirely possible both have the same muscle mass, and  thus also similar muscular power.
Is a 100 kg boar stronger than a 100 kg deer? In terms of simple strength (not aggression, weaponery, durability or fighting prowess)? I would not be so sure of that at all. Just that people generally have a feeling that that is correct doesn’t make it a fact. Clearly these animals are very differently proportioned, and hence have very different strengths and weaknesses, but how they would fare when directly compared to one another probably depends heavily on which body region or muscle and which movement is being compared.

Regarding humans with broad muscular chests, sure, they are certainly stronger than average people, but that’s because they are more muscular (not to mention also usually heavier) not simply because they are broad. People that have a broad chest that isn’t muscular, but just very obese, likely are not stronger than an average person, especially one of the same overall mass (in fact I would be fairly confident a very short but obese person is significantly weaker in any relevant strength metric than a tall, healthy person of the same body mass and with a normal physique). Also broad-chested and muscular people don’t necessarily have wider ribcages or skeletons than normal people, they appear wider due to the musculature that is around that skeleton. Quite different from comparing two animals that differ in width simply because the geometry of their skeletons is different, not necessarily because one has more musculature on top of that skeleton than the other.

We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator–prey pair, the predators had 20% higher muscle fibre power than prey,

www.nature.com/articles/nature25479

Very interesting! But I think you are misunderstanding the finding of that study. 

The higher power found here is related to the tissue properties of the muscle fibres, and has nothing at all to do with body shape. One muscle fibre from a lion will simply generate more power than one muscle fibre from a zebra. That’s related to the kind of muscle fibres cats have; white, glycolytic muscle tissue is capable of higher power output (but less endurance) than red, oxidative muscle, and cats have particularly high proportion of there high-power, fast-twitch white muscle fibres, ergo at the same overall muscle mass they produce more power than an animal with more red muscle mass (but also cannot sustain this effort for as long). This is true no matter what body shape the animals have, so it’s not surprising that the muscle power of a lion is greater than a similar-sized (or similar muscle-mass) zebra, even under the assumption that a more compact animal is generally more powerful. 

This is simply a shape-independent metric of muscular power. Which is also possibly the only metric that can easily and objectively be defined, as all other ways of quantifying how strong an animal is depends on which specific body regions, muscle groups and movements are compared (of which there are almost infinite possible combinations, so it will be very difficult to get a comprehensive measure of strength this way, not to mention they are of course not all equally important depending on what one wants to actually compare).

In a lot of cases people do compare similar massed creatures. Cheetahs for instance are roughly the same mass as leopards and seem considerably weaker.

Weaker how exactly? A cheetah can apparently generate sufficient power output to propel itself at a speed unmatched by any other terrestrial animal, so in that regard it is almost certainly stronger than a leopard. To accellerate the same mass to a faster speed necessitates more force, i.e. it means the animal is stronger (in terms of the specific muscle groups generating the force that is involved in locomotion, at least).

How would one quantify the overall shape-dependent strength of an entire animal?

Certainly animals can be stronger for some specific movements, but that usually comes at a cost. In the case of cheetahs, of course they are extremely cursorial, which comes at the expense of limb flexibility and distal limb musculature, meaning among other things they aren’t good grapplers or climbers. So even though they are undoubtedly very strong in some metrics, they cannot apply this strength in the same ways a leopard can.

Sure, but ceratosaurus seems to have a lot more vertical chest depth than most theropods.

Since I know of approximately four preserved Ceratosaurus ribs in total, that conclusion might be premature. Also based on available reconstructions, the way the chest of Ceratosaurus is usually portrayed doesn’t really look significantly deeper compared to similar-sized Allosauroids or Tyrannosauroids, albeit looking longer and less tapering. As I said though, how much of that has a basis in fact and how much is speculation isn’t all that clear.

Unfortunately, I never been able to memorize which people have reliable reconstructions are which ones don't.

That’s not really surprising, since this isn’t a simple case of memorization, but really needs to be considered on a case by case basis. Greg Paul, while of massive importance to the development of modern paleoart, does have his scientific idiosyncracies and doesn’t really use very modern techniques (for example as of the most recent interview I know of him, he was still doing his skeletons with pen and paper rather than digitally).

[Infinity Blade]

I don't really have anything substantial to add to the conversation at this point, but I think with regards to similar-massed herbivores vs carnivores specifically (e.g. the wildebeest/zebra vs lion comparison above), the herbivore more than likely has that massive ribcage because it needs to accommodate long, massive guts to digest plants. That isn't, however, necessarily an adaptation for strength. So for example, if you had an 8t T. rex (or for that matter, an 8t Giganotosaurus) and compared it to an 8t American mastodon, the proboscidean certainly has a bulkier ribcage, but I don't think it would necessarily be physically stronger than the theropod just because of that.

[Exalt]

Sept 6, 2023 22:44:12 GMT 5 Supercommunist said:

Well, why would one expect the bulk of the torso to have much relevance for how powerful an animal is (at similar overall mass)?

Those torsos are mainly composed of internal organs that do not contribute to strength, and are also not very flexible, especially when they are very bulky.

Generally speaking, bulkier and robust animals tend to be stronger than more gracile animals. Buffalos appear more powerful than similar sized elands, boars appear more powerful than deer at parity, humans with broad muscular chest tend to be stronger than humans with average chests. Smilodon are considerably bulkier than extant cats and most likely were more powerful wrestlers.

[/quote][/div]

While we're here, can I get a brief explanation of the science for how we know, or think we know, how muscular an animal would be? I've heard of "muscle attachment sites" in regards to bones before but that's all.

EDIT: Why do quotes keep messing up for me...

[Supercommunist]

"Appear stronger" seems rather like circular reasoning. As I acknowledged, more robust animals do indeed appear to be stronger to most people, but that doesn’t necessarily mean they actually are. If there is a quantitative comparison between the strength of a 1 ton eland and a 1 ton buffalo, I would be very interested in seeing it, as well as what kind of standard for comparing the overall strength of these animals someone might come up with. Clearly these two are not going to wrestle one another (and neither would a boar and deer for that matter). A shoving match then? Hmm maybe, but this could go either way. Given that both have similarly suitable equipment to actually shove with, a taller, more elongated animal has the advantage of height giving it better leverage and the ability to push down on its opponent, while the shorter animal has the advantage of a lower center of gravity, giving it better stability, but these are also not directly related to strength. If both are the same mass, then it is entirely possible both have the same muscle mass, and thus also similar muscular power.

Generally speaking, bulkier herbivores are more difficult to overpower. For instance, there are many accounts of buffalos fighting off several male lions at a time. Elands, by constrast, are easier to overpower and kill.

This isn't just my personal observation. Buffalo are noted to be more dangerous prey and marked as a level 2 threat while elands are a 1.



Graph comes from this lion study. zslpublications.onlinelibrary.wiley.com/doi/abs/10.1017/S0952836905007508

Elands are much better jumper than buffalos and while that does count as strength, overall buffalo seem to be more powerful animals.

You're right that a lot of the tissue within a torso are organs but I imagine animal with broader chests tend have more muscle within their torsos than organs. As IB pointed out, herbivores usually require extensive stomachs to digest plants so they have to devote more space to accomdate that stuff but if you herbivore to another herbivore, the bulkier while will probably have more chest muscles.

Regarding humans with broad muscular chests, sure, they are certainly stronger than average people, but that’s because they are more muscular (not to mention also usually heavier) not simply because they are broad. People that have a broad chest that isn’t muscular, but just very obese, likely are not stronger than an average person, especially one of the same overall mass (in fact I would be fairly confident a very short but obese person is significantly weaker in any relevant strength metric than a tall, healthy person of the same body mass and with a normal physique). Also broad-chested and muscular people don’t necessarily have wider ribcages or skeletons than normal people, they appear wider due to the musculature that is around that skeleton. Quite different from comparing two animals that differ in width simply because the geometry of their skeletons is different, not necessarily because one has more musculature on top of that skeleton than the other.

Humans are often obese but this is not true of most animals. Asides from hibernating bears, it's rare to see a wild animal being severely overweight. It's also true that athletes probably don't have huge rib cages, but then again, unlike humans in wealthy nations, there isn't going to be nearly as much physical and msucular variation amongst wild animals.

Very interesting! But I think you are misunderstanding the finding of that study.
The higher power found here is related to the tissue properties of the muscle fibres, and has nothing at all to do with body shape. One muscle fibre from a lion will simply generate more power than one muscle fibre from a zebra. That’s related to the kind of muscle fibres cats have; white, glycolytic muscle tissue is capable of higher power output (but less endurance) than red, oxidative muscle, and cats have particularly high proportion of there high-power, fast-twitch white muscle fibres, ergo at the same overall muscle mass they produce more power than an animal with more red muscle mass (but also cannot sustain this effort for as long). This is true no matter what body shape the animals have, so it’s not surprising that the muscle power of a lion is greater than a similar-sized (or similar muscle-mass) zebra, even under the assumption that a more compact animal is generally more powerful.

Sorry for not clarifying, I am aware that the power difference between lions and zebras is not due to bodyshape. I just linked the study to show you where I pulled the 20 percent figure from.

This is simply a shape-independent metric of muscular power. Which is also possibly the only metric that can easily and objectively be defined, as all other ways of quantifying how strong an animal is depends on which specific body regions, muscle groups and movements are compared (of which there are almost infinite possible combinations, so it will be very difficult to get a comprehensive measure of strength this way, not to mention they are of course not all equally important depending on what one wants to actually compare).

In a broad sense, I am sure there are some areas where zebras are stronger than lions, for instance, like you said it possible their lengs produce more kicking force even without the hooves. But lions are probably stronger when it comes to the areas people typically associate with strength such as high weight lifting ability or jaw strength.

Weaker how exactly? A cheetah can apparently generate sufficient power output to propel itself at a speed unmatched by any other terrestrial animal, so in that regard it is almost certainly stronger than a leopard. To accellerate the same mass to a faster speed necessitates more force, i.e. it means the animal is stronger (in terms of the specific muscle groups generating the force that is involved in locomotion, at least).
How would one quantify the overall shape-dependent strength of an entire animal?
Certainly animals can be stronger for some specific movements, but that usually comes at a cost. In the case of cheetahs, of course they are extremely cursorial, which comes at the expense of limb flexibility and distal limb musculature, meaning among other things they aren’t good grapplers or climbers. So even though they are undoubtedly very strong in some metrics, they cannot apply this strength in the same ways a leopard can.

It is true that running ability is a legit measure of strength. I, just have a tendency to view speed and strength as diffrent things even though they really aren't. For instance, Usain Bolt being one of the fastest men alive would have some of the strongest legs in history, but most people wouldn't really consider him an especially strong athlete and would probably consider a similar weight UFC fighter or weight lifter to be much stronger than him.

Since I know of approximately four preserved Ceratosaurus ribs in total, that conclusion might be premature. Also based on available reconstructions, the way the chest of Ceratosaurus is usually portrayed doesn’t really look significantly deeper compared to similar-sized Allosauroids or Tyrannosauroids, albeit looking longer and less tapering. As I said though, how much of that has a basis in fact and how much is speculation isn’t all that clear.

That's fair. I am rather sad how rare ceratosaurus seems to be and unfortunately it doesn't appear that ceratosaurus is nearly as popular as I would hope, so I don't expect to see any major studies done on it soon.

Also I missed the chance to discuss this point in my last post because the format of my response to you got messed up so I rushed to fix it:

Also there’s been the suggestion in the literature that Ceratosaurus may have been a good swimmer or even specialized for life in fluvial environments (as opposed to Allosaurus being more specialized for arid environments), in which case it is plausible that a laterally flattened body could have been useful as an adaptation for swimming (though I will readily admit that that’s not necessarily something we see in confirmed semi-aquatic animals).

We actually recently discussed the ceratosaurus' supposed aquatic adaptations in the ceratosaurus profile thread. I know there is not enough fossil evidence to support this idea, but I thought the notion that the ceratosaurus was a jaguar-like predator that often preyed on smaller semi-aquatic creautres like crocodilians was a really cool idea.

I don't really have anything substantial to add to the conversation at this point, but I think with regards to similar-massed herbivores vs carnivores specifically (e.g. the wildebeest/zebra vs lion comparison above), the herbivore more than likely has that massive ribcage because it needs to accommodate long, massive guts to digest plants. That isn't, however, necessarily an adaptation for strength. So for example, if you had an 8t T. rex (or for that matter, an 8t Giganotosaurus) and compared it to an 8t American mastodon, the proboscidean certainly has a bulkier ribcage, but I don't think it would necessarily be physically stronger than the theropod just because of that.

I think I was just taken aback by how thin a lion is when you remove the skin. I never considered lions bulky animals but I would have never described them as narrow. It doesn't help that some lions do appear rather bulky from the side.

[theropod]

Sept 7, 2023 4:13:45 GMT 5 Supercommunist said:

Generally speaking, bulkier herbivores are more difficult to overpower.

I can very well imagine that to be true, and they may be one relevant measure of how "strong" they are, but where is the evidence?

This isn't just my personal observation. Buffalo are noted to be more dangerous prey and marked as a level 2 threat while elands are a 1.

The buffalo in this table is also listed as 25% heavier (though all the masses seem curiously low), so this doesn’t prove anything about them at equal sizes. Also there are other factors besides raw strength that influence how dangerous a prey item is; in the case of cape buffalo, I would strongly suspect they are both better-armed and more aggressive (and, judging by this table, lconsiderably arger) than eland. So this doesn’t represent a proxy of simple strength, it just indicates how dangerous a prey item they are.

Elands are much better jumper than buffalos and while that does count as strength, overall buffalo seem to be more powerful animals.

Again, seem to be. But is a 1000 kg Buffalo objectively stronger than 1000 kg eland?

You're right that a lot of the tissue within a torso are organs but I imagine animal with broader chests tend have more muscle within their torsos than organs.

Exactly, you imagine. Lots of people share this imagination, but is there any reason why this should be the case?

Bulkier torsos naturally have greater rigidity (added to such adaptations as more elongate neural spines and strong spinal ligaments that often accompany them), so they likely need, and hence have, less muscle in order to maintain their posture. I do not claim to know this, nor take it as evidence of anything, but I would expect a lion’s more flexible torso to actually contain more muscle than a similar-sized zebra’s.

Even if they did have more muscle in their torso, which I do not see any reasonable cause to suspect, since the torso is fairly immobil, that would again throw up the question of what is a relevant metric of strength, as that muscle couldn’t effect much movement as opposed to muscle in the limbs, neck, or tail.

As IB pointed out, herbivores usually require extensive stomachs to digest plants so they have to devote more space to accomdate that stuff but if you herbivore to another herbivore, the bulkier while will probably have more chest muscles.

A giraffe has a more compact torso than a buffalo or a rhino, does it have more chest muscle at equal body mass? And, if so, why?

Humans are often obese but this is not true of most animals. Asides from hibernating bears, it's rare to see a wild animal being severely overweight.

There is no such thing as "overweight" for a healthy wild animal, but the amount of body fat among different animals, life stages and times of the year varies massively (certainly bears are not unique in having fat reserves), and it’s not reasonable to suspect that herbivores have massive amounts of muscle somewhere where it isn’t needed or useful due to a presumed correlation of relative muscle mass with body shape that lacks empirical support.

It's also true that athletes probably don't have huge rib cages, but then again, unlike humans in wealthy nations, there isn't going to be nearly as much physical and msucular variation amongst wild animals.

Exactly, there is not. Which is why comparing an athlete to a non-athlete is not a good analogy for comparing different animals that just happen to have different ribcage geometry, but (unlike athletes vs non-athletes) not necessarily different muscle mass.

Sorry for not clarifying, I am aware that the power difference between lions and zebras is not due to bodyshape. I just linked the study to show you where I pulled the 20 percent figure from.

Ah ok, but then I don’t get the relevance of the figure, or why one would be surprised by it due to the body shape, as it has nothing to do with, nor would be expected to be influenced by how wide their torsos are.

In a broad sense, I am sure there are some areas where zebras are stronger than lions, for instance, like you said it possible their lengs produce more kicking force even without the hooves. But lions are probably stronger when it comes to the areas people typically associate with strength such as high weight lifting ability or jaw strength.

Well, jaw strength is a single very specialized area, and yes, very likely greater for the lion. That is sort of the point, it’s difficult to objectively compare strength across an entire animal, but easy to compare strength in particular areas.

I am not so sure if jaw strength is more typically associated with strength than how forceful something can kick or punch. Seeing how people usually have a very human perspective, I would say the opposite.

As for weight lifting capacity, seeing how horses have been used for carrying heavy weights for millenia, I would guess that they are relatively strong in this regard. As for a lion’s weight-lifting capacity I have honestly no idea, I don’t know if anyone has ever tried riding a lion.

It is true that running ability is a legit measure of strength. I, just have a tendency to view speed and strength as diffrent things even though they really aren't. For instance, Usain Bolt being one of the fastest men alive would have some of the strongest legs in history, but most people wouldn't really consider him an especially strong athlete and would probably consider a similar weight UFC fighter or weight lifter to be much stronger than him.

Yes, but wild animals don’t do MMA or weightlifting. In an objective, quantifiable way, Usain Bolt is likely extremely strong. He might not win an MMA fight against someone who has specifically trained the muscle groups and movements (not to mention the techniques) needed for MMA, but an MMA fighter is also never ever going to win a race against Bolt. And while sheer speed is not usually that important in a confrontation (which most of the people here are primarily interested in), the muscles needed for it do impart some other, more relevant metrics of strength, see aforementioned example about kicking. But also if you take two similar animals, and give one the muscles needed to run faster, that animal is also likely going to be able to push or pull greater loads than another same-sized animal without these adaptations, because the muscles that generate the energy needed to produce the force needed to accellerate the animal body to a certain kinetic energy are also going to be needed to acellerate any load that it pulls or shoves.

That's fair. I am rather sad how rare ceratosaurus seems to be and unfortunately it doesn't appear that ceratosaurus is nearly as popular as I would hope, so I don't expect to see any major studies done on it soon.

Indeed, Ceratosaurus is understudied, and besides some qualitative, subjective and rather old interpretations, there’s very little about its jaw function in the published literature. Exacerbating that, there’s little regard for morphological differences between the small, subadult holotype and larger, more robust specimens. I have been thinking of perhaps doing a comparative study of its jaw apparatus at some point, if I can get my hands on some scans of a well-preserved skull that is. Some bending strength metrics for its rostrum or mandible, and a comparison to Allosaurus and Tyrannosaurus in this regard, might be interesting. But sadly I haven’t found any publicly available ct scans so far, and I’m not going to blow several tons of carbon in the atmosphere and spend a few thousand bucks to cross the Atlantic just to do that single thing.

Really, it is pretty frustrating how we can see dozens of studies on the jaw mechanics of the single species T. rex (sorry Greg) come and go, while hugely diverse lineages of theropods, like all ceratosaurs, all megalosauroids (not to mention all carcharodontosaurs) can be go almost entirely unstudied in the same regard, even when there is good skull material available (as in the case of Ceratosaurus or various Abelisauroids).

Also I missed the chance to discuss this point in my last post because the format of my response to you got messed up so I rushed to fix it:

Also there’s been the suggestion in the literature that Ceratosaurus may have been a good swimmer or even specialized for life in fluvial environments (as opposed to Allosaurus being more specialized for arid environments), in which case it is plausible that a laterally flattened body could have been useful as an adaptation for swimming (though I will readily admit that that’s not necessarily something we see in confirmed semi-aquatic animals).

We actually recently discussed the ceratosaurus' supposed aquatic adaptations in the ceratosaurus profile thread. I know there is not enough fossil evidence to support this idea, but I thought the notion that the ceratosaurus was a jaguar-like predator that often preyed on smaller semi-aquatic creautres like crocodilians was a really cool idea.

It is, yes. And who knows, maybe there really was this sort of environmental niche partitioning in the Morrison. Maybe at some point there will finally be some renewed interest in Ceratosaurus (and Jurassic or Morrison theropods in general) that will lead to some more insights on this. This goes for jaw mechanics as well. I know there’s an ongoing project that might potentially include Ceratosaurus, so we can hope.

[theropod]

Sept 7, 2023 4:10:05 GMT 5 Exalt said:

While we're here, can I get a brief explanation of the science for how we know, or think we know, how muscular an animal would be? I've heard of "muscle attachment sites" in regards to bones before but that's all.

The size of muscle attachment sites is roughly proportional to the thickness of the muscles that attach to them, so the size (read: area) of muscle attachment sites can be used as a proxy for the size of muscles (take for example the lateral area of the iliac blade in theropods, from which we know the thigh muscles originate, or the lateral area of the proximal caudal centra and haemal arches, from which the caudofemoral muscle originate).
That is because logically, a muscle that produces a larger force will also need a larger, stronger attachment to bone, so theoretically, the larger the attachment areas, the bigger and stronger the muscle is likely to be.

However, in reality a lot about how muscular people perceive certain animals to be is speculation, and there aren’t really any quantitative estimates for how much muscle specific extinct animals would have in total based on their skeletons. While theoretically possible, such an estimate would be very time-consuming, and in addition have such wide error-margins that it would not be very meaningful anyway, so usually people just guesstimate muscle volumes based on comparison with extant animals and how large their muscles are relative to the bones.
Also, quantifying the size of attachment sites itself is not that straightforward, as not all muscle attachment sites are always neatly delimited and marked with a sharpey as "muscle x attached on this area". So there will always be a lot of inherent uncertainty and speculation in estimating the size of an extinct animal’s muscles, meaning error bars for absolute estimates are very large (but you can get a much better idea of relative muscle sizes by comparing related animals to each other).

Also, sometimes muscle volumes are constrained by other osteological stops, for example we know many jaw adductor muscles must pass through the adductor chamber of the skull, so that cannot be thicker than what would fit in that chamber, representing an upper limit to their size.

[Exalt]

So is the idea that Smilodon was so muscular based on having different shapes to its bones than pantherines?

[Supercommunist]

Bulky jaguar.



www.sciencephoto.com/media/387476/view/view-of-a-jaguar-panthera-onca-on-the-prowl

I think this picture also illustrates why shrink wrapping is so pervasive. If all cats were extinct and we only had the fossils most wouldn't envision them getting getting that bulky.



www.artstation.com/artwork/5BPVgO