theropod1 In reply to TriceratopsHorridus [2022-06-10 21:37:06 +0000 UTC]

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theropod1 In reply to Dragunalb [2021-06-04 22:01:42 +0000 UTC]

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theropod1 In reply to ThaAnonymousPerson [2017-11-24 22:25:53 +0000 UTC]

yes

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theropod1 In reply to Dinopithecus [2017-03-23 08:38:18 +0000 UTC]

First of all, depends on the theropod in question, they aren't that similar across the ranks in that regard. Some had more flexible necks than others. And of course it depends on what angle the opponent would be relative to the theropod.

So rather than giving you an overgeneralized answer to that question, here’s a very helpful visualisation from Snively et al. 2013:
palaeo-electronica.org/content…

Shown (3) is the maximum lateral range of motion of the head and neck of Allosaurus.
A couple of things to note: Of course Allosaurus is considered one of the large theropods with a rather high degree of cervical flexibility. I don’t know much about Megalosaurs in this regard. A derived tyrannosauroid would almost certainly be less flexible, but of course it would also have a shorter neck to make up for that, which would make grappling it even more difficult.
As you see the individual joints, including the craniocervical articulation, aren’t all that flexible, but if you add up the angles over several you end up able to flex that neck quite a bit rather quickly. So it’s very important to take into consideration where that hypothetical grappling animal has its hold on the neck, and how much of its length is still free to move. That’s of course also relevant because grappling more anteriorly would give the grappler much better leverage and make escaling its grasp much more difficult.
So perhaps theropod flexibility was sufficient for what you describe, perhaps not, depending on where the attacker is standing compared to the theropod and what theropod we are talking about.

As for shaking vigorously, there are certainly theropods I could see doing that, though of course the neck is a vulnerable region and doing so would be risky. But again, depending on the attacker I suppose it could work in some cases.

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Dinopithecus In reply to theropod1 [2017-03-24 22:27:38 +0000 UTC]

"As you see the individual joints, including the craniocervical articulation, aren’t all that flexible"

Yeah, I find that puzzling. I read that the large articular surfaces of theropod zygapophyses promoted neck flexibility; I imagined it would be by making the individual joints flexible. The opisthocoelus morphology of carnosaur cervicals should also have helped with this. Lastly, Snively's reconstruction doesn't look like the cranium is flexed all that much from the atlas, but theropods had more or less spherical occipital condyles, allowing for great mobility at the joint.

Did these things just really not help that much to make the individual joints flexible in absolute terms?

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theropod1 In reply to Dinopithecus [2017-03-25 22:17:09 +0000 UTC]

I didn’t mean to say Allosaurus’ neck wasn’t flexible. For a cervical skeleton, it’s in all likelyhood very flexible. But individually, intervertebral joints or the craniocervical joint still don’t have huge ranges of movements.
They never do, probably those in Allosaurus already have a comparatively large range of movement (as you correctly point out, they are in fact adapted for that), but individual vertebrae simply don’t move all that much. It’s the summation of many small rotations that ends up making the neck flexible.
What I meant to say by that: it really matters how much neck there is to make that turn you were referring to, because it can’t just bend 90° in a single spot.

Simply put, the measure of what’s flexible for an intervertebral joint isn’t the same as that for a jaw joint, or knee joint etc., because they don’t have to be and vertebrae are loaded in a very different way from jaw or limb bones. They need those support structures, like zygapophyses, cervical ribs and neural spines to provide adequate support to the spine without excessive muscular effort despite its mostly horizontal posture. Allosaurus does have a comparatively flexible neck. Part of the reason why is that its skull likely wasn’t very heavy compared to some other theropod skulls, meaning it needed less rigid support. But still individual vertebral joints will generally not be as flexible as some other joints in the body, and this is why.

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Dinopithecus In reply to theropod1 [2017-03-27 21:29:19 +0000 UTC]

Oh, don't get me wrong. I remember past comments from you about Allosaurus' neck flexibility; I don't think you would ever claim its neck wasn't flexible with the evidence at hand. It just surprises me a bit that individual cervicals never have absolutely large ranges of motion, regardless of how flexible they are relative to others.

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theropod1 In reply to Dinopithecus [2017-03-28 11:31:56 +0000 UTC]

That might be surprising, I can relate.
But think about it. If individual intervertebral joints had huge ranges of motion, summing that across all joints in the neck you’d quickly end up with a neck that could curl in on itself 360° or more.
That would neither be hugely beneficial, nor would it come without major drawbacks attached to it.

Large amounts of soft tissue and the size of the skull would prevent such extreme motions from being possible anyway. So if nd what purpose would that flexibility really serve in the first place? Allosaurus is not a swan that would or could use its jaws to order or clean its plumage. Nor is it a venomous serpent that would just need the tiniest of nicks in the skin and some venom to be fatal (not to dismiss the possibility of venom outright, but currently I’ve seen no concrete evidence of venom, and Allosaurid anatomy doesn’t really seem to necessitate it).

And lets not forget that it you give each of these joints unlimited flexibility, that will come at the cost of strength and durability. So while a swan-necked Allosaurus may have an easier time turning around to bite something that’s grabbing its neck, what use would that be if the attacker has already snapped that neck before it can retaliate, or if it doesn’t have the strength to do any damage to what it bites. Really the only animals where I’d envision such excessive flexibility would be useful in such a scenario are those that have very potent venom.

Adapting for maximum ability to counterattack something once it’s gotten a hold if its neck is likely not a good survival strategy from an evolutionary perspective though. You wanna keep things from getting to your neck in the first place. Once again something that a decent pair of jaws and the neck strenght to support them are a better way of accomplishing than an excessively flexible neck.

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Dinopithecus In reply to theropod1 [2017-03-29 22:29:12 +0000 UTC]

You make a good point with the last paragraph (you wanna make sure your neck isn't grabbed in the first place). I just wanted to know whether or not theropods could free themselves if they did get caught.

Though, in a fight with a cat or bear with arms that have wide spans for grabbing something, do you think could they do this and bring their assets to bear first?

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theropod1 In reply to Dinopithecus [2017-03-30 12:47:22 +0000 UTC]

Do what? prevent them from grabbing their neck, or freeing themselves afterwards?

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Dinopithecus In reply to theropod1 [2017-03-30 12:55:14 +0000 UTC]

The former (and additionally, be the first to gain purchase). I believe you've already said that it depends on the circumstances regarding the latter.

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theropod1 In reply to Dinopithecus [2017-03-30 16:13:44 +0000 UTC]

Well, yeah, of course.
I’d expect that once you give another animal that is intent on killing you free access to your neck, you’re pretty much done for.
So I highly doubt in a clade that brought forth almost all large land predators during a 150Ma time span the members would not have learned to keep adversaries from reaching their throat.
Most (it goes without saying, macropredaceous) theropod bauplans are optimized to bite first, cuddle later. There’s a pretty big set of jaws between that neck and anything trying to reach it from the front, so obviously in a fight anything trying to get to that neck has to get past the jaws, which are the theropod’s main means of offence. So I’d say getting there would be pretty difficult. A neck isn’t automatically easier to get to just because it’s longer, in a frontal assault that has very little bearing and even at an angle that neck just has to turn in order to be protected by the skull once more.

So since whichever one manages to get to the opponent’s neck first will usually win the fight, the question of whether they could prevent something from grabbing their neck is pretty much tantamount to asking whether they could fight at all.

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Dinopithecus In reply to theropod1 [2017-04-02 04:38:34 +0000 UTC]

Also, what do you think of the new "no lips for tyrannosaurids (as per Daspletosaurus horneri)" conclusion by Thomas Carr?

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theropod1 In reply to Dinopithecus [2017-04-02 15:08:57 +0000 UTC]

Actually I’m not even sure whether this necessarily completely rules out the presence of lips (Though admittedly the rough bone texture is unlike that in squamates or mammals, this wasn’t actually addressed by Carr and colleagues), although the confirmed similarities to crocodiles would make that appear likely (and the tactile-faced hypothesis has previously been associated with lack of lips). But it would appear that at least tyrannosaurids probably didn’t have lizard-like lips from what we can tell now. The evidence for this never was that strong in the first place and Carr et al.’s recent paper isn’t the first work to provide indications to the contrary.

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Dinopithecus In reply to theropod1 [2017-03-31 02:12:44 +0000 UTC]

Hmm, yeah.

Then I have to wonder, if a hypothetical carnosaur, megalosaurid, tyrannosaurid, or whatever macrophagous head-first theropod fought an equal sized bear or cat, would something like a 50/50 sound logical?

And sort of unrelated to this, some people have said (on Carnivora, no less) that the inability of theropods to pronate or supinate their hands disallowed them to grapple and wrestle with prey as per animals such as felids, ursids, and mustelids. Is this true?

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theropod1 In reply to Dinopithecus [2017-04-02 15:17:13 +0000 UTC]

That’s always a logical baseline to start from when evaluating any hypothetical combat scenario, although of course the sheer diversity of the taxa you list is way too high to give you a blanket statement like that. So the possible outcomes could still vary widely depending on the two particular taxa you are comparing. In some pairings the carnivoran will be more formidable, in others the theropod.

And of course a theropod would never grapple and wrestle with its forelimbs in the same manner as a carnivoran, but I don’t think that has much to do with their forearm mobility, rather with forelimb length and posture, and to an extend the limited range of protraction. A cat trying to grab something will also turn its palms inward for that, it’s just the best posture for doing that, which is why theropod arms adopted it permanently in the absence of a need to use them for locomotion.

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theropod1 In reply to Dinopithecus [2016-09-27 11:54:34 +0000 UTC]

Just because it would be a shame to leave this unanswered, even though this is pretty much just what I wrote on WoA:
I think their way of solving that problem was simply by producing more force.
Quadrupeds have better leverage because they have two leg pairs, but most theropods have humungous musculature powering their hindlegs, i.e. more force to make up for that. Whether they could produce just as much torque I don’t know, but even if not, how fast a quadruped can turn may be limited for other reasons than the sheer ratio between torque and RI.
The rotational inertia would likely be somewhat greater due to their more elongated body shape than the typical quadruped, but that’s certainly highly dependant on the theropod and quadruped in question (theropods do have more or less effective means to lighten the ends of their bodies).
This is partly offset by what we already discussed; potentially quicker capacity of excerting torque because of shorter moment arm, and flexing of the body (also more effective in some theropods than in others) while turning in order to reduce RI. I’ve got no quantification of this, but I doubt this is enough to offset their long body shapes and make them able to turn on the spot just as well as a same-sized quadruped. However as I wrote

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Dinopithecus In reply to theropod1 [2016-12-06 18:30:40 +0000 UTC]

About that topic (or really to deviate from it):

Remember how you said elephants are kind of a (rough, at least) sauropod analogue when it comes to dealing with predators (they're neither behaviorally nor anatomically adapted for dealing with predators as massive as they are)? Well, another person I asked on Carnivora agrees that their body plan takes advantage of being so large.

Do you know of any ways this might hold true? That is, what about their anatomy makes them so reliant on size? Having tusks makes it kind of hard to believe (although, I recently read a publication saying that elephant tusks have a rather low tensile strength and are susceptible to fracture, for whatever it's worth).

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theropod1 In reply to Dinopithecus [2016-12-09 12:33:42 +0000 UTC]

I’m not sure what you mean by "their body plan takes advantage of being so large". Every large animal takes advantage from that large size, otherwise it wouldn’t have become large in the first place. And every body plan depends on its owner being the size at which it evolved to function properly.

Surely an elephant tusk could fatally injure an elephant-sized animal given the right circumstances.
The point is that there are body plans, weapons, and importantly, behavioural adaptions that would be better suited to do so.
If I recall correctly I touched on this the last time I discussed this: despite their undeniable intelligence, they still never, in their entire evolutionary history, have had to deal with predators that were anywhere close to their own size, and it seems unlikely an elephant that had to do this suddenly would be up to the challence simply on the basis of using the appropriate behavioural response.

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Dinopithecus In reply to theropod1 [2016-12-15 22:55:34 +0000 UTC]

I'm sorry, are you busy? I'm still eagerly awaiting your thoughts .

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theropod1 In reply to Dinopithecus [2016-12-17 19:01:30 +0000 UTC]

Oh, sorry about that. Yes, pretty busy at the moment but nonetheless I should check DA more often. So please excuse the delay.
I think something like a ceratopsian is better protected all-round both due to its body shape being lower and its more bony/horny face (although with some recent suggestions admittedly they might have had some serious soft tissues not previously expected, but I take it that those would not be exposed or vital to the degree an elephant’s trunk is) and overall more compact bone structure. Plus in a direct comparison most ceratopsians horns seem like they will provide better penetration against something large.

Thyreophorans’ main advantage is that they have their weapons on their tail. I think it’s not difficult to see the benefit of not attacking with a body part that houses so many vital and vulnerable structures as the head does. Having your weapon on the end of a long tail is pretty much perfect for keeping an opponent at a distance, so as long as they can turn to face an attacker they are very hard to beat for something similar in size.

With suids, it’s not so much their weaponery that I find so impressive, but rather their resilience and having proven to have the aggression to be a threat to large predators repeatedly (records of tigers disemboweled by boars and lions killed by warthogs, as well as how peccaries do against jaguars, not to mention what boar can and have done to human hunters).

Additionally, elephant’s columnar legs aren’t the best at providing flexibility and maneuverability, including bringing their tusks to bear. Obviously this is not a problem nowadays, because elephants never need to match other animals their own size anyway, and because they could never match extant predators in the first place. But when you are a Tyrannosaurus and your choice is between attacking a 6t-Triceratops and attacking a 6t african elephant, the Triceratops would likely be more trouble.

But what I’m saying is not that elephants would be helpless against similar-sized opponents (at least not on the grounds of functional anatomy, though I think if an elephant encountered a predator the same size as itself it would be pretty prone to panic). It’s just that in modern ecosystems their role is consistently comparable to that of large sauropods in the mesosoic; they’ve never had to face similar-sized predators because there never were terrestrial predators that big during the cenozoic, so they aren’t ideally adapted for protecting against them. On the other hand, thyreoporans, suids and ceratopsians evolved alongside same-sized or bigger predators and at least for the dinosaurs, their weaponery evolved so prominently that I’d downright call it an arms race.
Just my take of course, I’m absolutely open to counterarguments, and there are certainly many people out there with much better knowledge on elephant biology than I have.

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Dinopithecus In reply to theropod1 [2016-12-17 20:10:11 +0000 UTC]

I also recently read from a publication that recorded male Asian elephant combat (in one particular population). In tactile fights, they more often headbutted or wrestled than gored. The authors cited the low tensile strength of elephant ivory as a potential reason for this; it's apparently almost twice as low as that of the culms of some bamboo species (~110 MPa vs. 219 MPa). The authors even said that tusks could possibly be broken by the weight and trunks of elephants on the basis that the animals could easily do the same to bamboo (some bulls were also observed draping their trunks over an opponent's tusk and pressing down with their weight; here's a link ).

Looking at videos of (African) elephant fights, it looks like they too also bump and wrestle with their heads more often than they actually try to gore. If elephants never lived with predators as large as themselves, might we expect them to sometimes headbump and wrestle and not even gore (although, giant crocodilians are probably too low to the ground for them to try this)? And if their tusks are really susceptible to fracture, wouldn't this also prove to be a disadvantage?

But about panicking on sight: someone on Carnivora doubted that elephants (or other megaherbivores like rhinos) would even recognize mega theropods as predators. Do you think this would hold true?

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theropod1 In reply to Dinopithecus [2016-12-19 15:10:09 +0000 UTC]

That’s interesting information. But also a bit confusing.
I used to think keratin had a very high tensile strength (composite bows are made from buffalo horn for crying out loud), but doing some reading just now, the truth of the matter is that its tensile strength is extremely dependant on the moisture content, and at 19% moisture it’s just 40MPa (see here: meyersgroup.ucsd.edu/papers/jo… ) while when fully dry it’s much higher.
We can probably agree about the effectiveness of horn in its various applications as weapons, and others do too, even pointing out the remarkable fracture toughness of the material. So tensile strength isn’t the only thing of significance to how resistant a structure would be at resisting fracture.

Also, headbutting is awfully common in intraspecific conflicts, but not that much in any other context I know of. Maybe that’s actually a mechanism to prevent injuries. Now, I’m not surprised that in sheep fractured spines are the most common causes of death after intraspecific conflict (how else would they kill each other?), but how common are such injuries overall? More common than they’d be if both had sharp horns that they’d use to stab each other? I find that unlikely.
So the question is not just what elephants would use to attack a large opponent, but also what they use when they are fighting to kill.
Here’s an elephant goring a buffalo: www.youtube.com/watch?v=xkqh2s…


Actually, no idea whether an elephant would recognize a megatheropod for what it is, that’s pretty much impossible to answer. Elephants are pretty damn smart, and theropods have some features that might be rather telling of their predatory nature (in terms of teeth, jaws, and claws)–at least humans have never had the slightest trouble recognizing T. rex or Carcharodontosaurus as predators without having ever seen one before.
On the other hand, no adult elephant knows any animals its own size that aren’t conspecifics, and it might be a pretty big leap to assume it would associate some 6t behemoth with the lifestyle it knows from 200kg lions or 50kg hyaenas…
I really can’t even give you an educated guess as to how they’d react. For me it’s a 50/50 matter. A bit like speculating whether we would accurately judge whether an alien was a friend or foe with limited time for observation and no data to go on.

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Dinopithecus In reply to theropod1 [2016-12-19 21:18:05 +0000 UTC]

"We can probably agree about the effectiveness of horn in its various applications as weapons, and others do too, even pointing out the remarkable fracture toughness of the material. So tensile strength isn’t the only thing of significance to how resistant a structure would be at resisting fracture."

That's a valid point. However, given the way tusks are shaped and how they're used, I feel like tensile strength would be quite significant to their resistance to failure. If we consider, as an example, elephants locking their tusks and wrestling, the tusks are most likely going to experience bending stress (especially if the heads themselves aren't making the most contact), in which tensile stress is experienced outside of the bend (and while I'm only now learning physics, apparently if the material yields to the compressive stress at the inside of the bend before it yields to tension, which is apparently the case for most materials, the bending strength IS the tensile strength).

Of course, a theropod or crocodilian isn't an elephant to lock tusks with, so that's why I wonder if what I just said would really matter in a fight with them. I was wondering if maybe robust skulled and toothed tyrannosaurids and crocodilians might be able to bite onto a tusk as a protective means and perhaps end up (unintentionally) breaking it with their power.

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theropod1 In reply to Dinopithecus [2016-12-20 12:09:28 +0000 UTC]

Hmm, bone is vastly stronger in compression than it is in tension, so it ought to fail in tension first when bending. But that's actually what results in the tensional strength determining bending strength. With wood, and probably bamboo too, it's the other way around, they are weaker in compression.

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Dinopithecus In reply to theropod1 [2016-12-21 04:55:34 +0000 UTC]

So what do you think of my idea of predators possibly biting a tusk and (possibly unintentionally) breaking it with their strength, possibly as a means of defense from goring? At first one might consider how dangerous that would be, but given how the elephants in that study sometimes gained advantages by grabbing opponents' tusks and pulling down with their weight (thus putting their trunks at risk of being punctured, which would create problems both in the short and long run), I have a feeling that maybe it won't be as risky as one might think. Is it a bad kind of crazy or is it conceivable?

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theropod1 In reply to Dinopithecus [2016-12-22 09:13:27 +0000 UTC]

Not a bad idea at all, in fact that's very reasonable.
Considering there's ample fossil evidence for T.rex using that tactic against Triceratops, it would be only natural in an encounter with an elephant. What I don't know is whether it would be a means of attack, or rather a defense, ass it seemingly was with trike.
But as I've hinted before, I think in fact the whole face-biting thing would likely be more effective on an elephant since in addition to the tusks there's also that trunk, which may be big and strong to a modern predator, but is just waiting to be torn off by an attacker big enough to do that.

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Dinopithecus In reply to theropod1 [2016-12-24 04:47:08 +0000 UTC]

That's good to know, heh.

Would carnosaurs, with their less solidly-constructed skulls and more blade-like dentition, have a different approach?

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theropod1 In reply to Dinopithecus [2016-12-28 22:34:29 +0000 UTC]

Using this approach might break a few teeth, but since that’s not really much of a concern it’s certainly a viable defensive tactic. There would be less force involved, and probably not that much of an attempt to break or bite off the tusks or horns or gain control over the opponent by sheer strength.
Much like even if you were nowhere near strong enough to overpower the wielder or gain full control of their weapon, if someone came at you with a polarm you’d be far better off if you were able to grab hold of the shaft, to maneuver not just the weapon itself but also yourself in relation to it.
However, some more forceful grappling could potentially be accomplished by means of recruiting the strength of the upper body by using the forelimbs, somewhat like the way komodo dragons wrestle each other, but this would likely be after making initial contact with the jaws.

Also, all the more so with a carnosaur’s dentition, I think the trunk and the other facial soft tissue would be a prime target. a well-placed bite there would not necessarily be fatal, but certainly extremely painful and debilitating, not to mention that it would lead to massive blood loss and potentially affect the elephant’s sensory capabilities. My guess would be that such a bite would leave an elephant quite impaired in its capacity to defend itself, and open to further attack to its legs or belly, which would fully cripple or kill it.

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Dinopithecus In reply to theropod1 [2016-12-31 00:27:52 +0000 UTC]

Okay. But I'm kind of having trouble envisioning a carnosaur employing its forelimbs in such a scenario, especially if it's something like a short-armed carcharodontosaurid. What body part would the forelimbs hook onto? The tusk? Some part of the face behind the tusks?

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theropod1 In reply to Dinopithecus [2017-01-01 21:34:37 +0000 UTC]

I’d imagine that if it bit onto them, that should provide sufficient control to step in and push with its chest, using the forelimbs as an anchor point. Whether gripping the tusks or the face behind them would be more advantageous would probably depend on the individual elephant’s tusk length.
But isn’t this whole scenario a little too far from reality anyway?

On a different note, to come back to the tensile strength issue I think the comparison with bamboo is sort of flawed. Bamboo may be very strong in tension, but its only half that strong in compression. With bone, we’ve got the complete opposite situation, and ivory is probably pretty close to bone.
Bamboo isn’t twice as strong as ivory, it’s just potentially twice as strong in tension. On the other hand, ivory is twice as strong in compression. So in the end they are merely limited by different material properties, but their overall strength is about the same. And I think the strength of a solid piece of bamboo with the diameter of an elephant tusk is nothing to look down on.

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Dinopithecus In reply to theropod1 [2017-01-02 06:32:22 +0000 UTC]

I hadn't thought of that. That ivory would have something against bamboo to make up for its inferior tensile strength (namely superior compressional strength) makes a lot of sense. Good point.

One final thing I've been wondering about is the way predators like big cats and bears are rated against large well armed herbivores and how predatory dinosaurs compare. On Carnivora, you see people of the idea that felids and ursids would stand reasonable chances in a fight against say, bovines, even when the latter are some number of times larger (on the basis of recorded predation events). You don't really see people claiming the same for carnivorous dinosaurs; theropods are pitted against elephants and rhinos their own weight. I get that these predators are completely different, but I've always been of the idea that predatory dinosaurs still had their own effective means for macropredation as well.

What do you think of the whole thing? Do you agree with all this predator (be it a cat, bear, theropod, etc.)-beating-multiple-times-heavier-and-well-armed-herbivore stuff?

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theropod1 In reply to Dinopithecus [2017-01-03 19:50:28 +0000 UTC]

Well, sort of.
I think a theropod would have a more difficult time than a carnivoran, but would still generally be capable of it (just perhaps not as often, or with prey quite as large proportionately speaking).
Not because theropods are somehow inherently flawed compared to cats, as I’m pretty sure some people on cf believe somewhere deep down, but because macropredation becomes more difficult as the combatants become larger, because using size, i.e. brute force and blunt trauma, as a weapon becomes easier and specialized weaponery becomes less important.

So a 2t Allosaurus has a harder time against something twice its size than a 200kg lion.
But still theropods seem to have been quite capable of bringing down prey a few times larger than themselves. Where it gets difficult is with the "well-armed" part. Obviously a sauropod is not particularly well-armed, certainly not by comparison with an elephant of the same size, let alone a rhino, but I’d question whether that’s still that important at the scale we are talking about. For a sauropod, and indeed an elephant too, it’s a lot easier to just kick and trample a smaller predator than it is to use claws or tusks to kill it.
So I think a sauropod isn’t particularly lacking in terms of defenses against a smaller attacker. This is also part of why elephants aren’t such bad sauropod analogues in terms of trophic interactions. Where the sauropod turns out notably less capable is when pitted against a similar-sized adversary, where some sort of stabbing/goring weaponery really comes into its own as just crushing the opponent with your superior weight and strength isn’t an option any more.

There’s reasonable evidence that Allosaurus- or Torvosaurus-sized theropods at least occasionally took Camarasaurus-sized prey for example. So I’d think they wouldn’t cut a particularly poor figure preying on an elephant either. That’s of course in a hunting scenario, not a fight. Clearly in an all-out, face-to-face fight a correspondingly smaller theropod would have a similarly poor chance against an elephant as a lion would against a buffalo, but the sort of scenario where they’d be likely to interact would be pretty different.
As for the evidence for predator-prey relationships with similar-sized, very well-armed prey, you are as well aware of it as I am, but I should reiterate here that I’d rate a stegosaur or ceratopsian a little higher than I would a bovid or elephant for a given size.

Now, as you may recall from that discussion I had on the DML some time ago, there are some who would disagree and hypothesize that most large theropods didn’t hunt prey their own size or larger at all, but I cannot seem to bring that into accordance with fossil evidence or functional anatomy. Many things about carnosaurs and megalosaurs are simply ridiculously overpowered if they didn’t attack large prey on a somewhat regular basis.

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Dinopithecus In reply to theropod1 [2017-01-04 01:11:09 +0000 UTC]

From this I reckon that smaller theropods (e.g. the lion-sized Marshosaurus or the leopard-sized Deinonychus) would fare better at macropredation than their larger brethren because their prey would be less capable of using size as a weapon (obviously though, the maximum size of the prey range will only go so far). Wouldn't these folks, then, fare as well at macropredation as predators in their size range like carnivorans or oras?

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theropod1 In reply to Dinopithecus [2017-01-04 22:28:12 +0000 UTC]

My guess would be that they would, yes.

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Dinopithecus In reply to theropod1 [2016-12-09 17:12:19 +0000 UTC]

By that he meant that elephants aren't "...terribly formidable pound for pound." That on a proportional basis, the elephant body plan just isn't that well suited for fighting similar sized predators and not as suited for messing something up as well as them.

He knows that elephant tusks can kill equivalent sized animals; he made that clear before a couple times. He just thinks that, well, what I just mentioned above.

If elephants don't have the best suited bauplans and weapons for fighting similar sized predators, then how, specifically, do they compare to animals that do? Like, how exactly are the weapons and other anatomical features of a ceratopsian, thyreophoran, or suid (examples you gave for the latter) better for this task than those of an elephant? I might have some clues, but I feel like you have better insight to this question than I do.

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theropod1 In reply to kirkseven [2016-08-21 11:25:35 +0000 UTC]

It could. However note that MOR 008 seems to plausibly fall within the 11-11.2m range itself, at least based on its more accurately restored skull length of 1.34m.

The question is how to get an unbiased sample, especially if we have got individual subsamples that differ markedly from each other.

The statistical significance is not high either way, but the figures could at least be indicative if we can objectively sample and estimate as many specimens as possible (in fact there are probably even enough T. rex specimens to get fairly significant results, well over 50 in total, but we lack data on many of them and will probably not get them any time soon).
That way at least 15 or 20 specimens will give us a much better idea of the normal size of the species than one, so lack of statistical significance is no reason not to at least do the best we can.

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kirkseven In reply to theropod1 [2016-08-21 16:05:37 +0000 UTC]

About MOR 008 it does appear to look similar to
AMNH 5027 which could suggest something longer
Than sue. (I'm not sure if it would be heavier)

And blazes image seems to suggest that the corrected
Version of the skull is 140cm going by pixel count.

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theropod1 In reply to kirkseven [2016-08-27 09:09:34 +0000 UTC]

That depends on how you measure it. I had forgotten Blaze assumed the measurement to be Pmx-qj, so yeah, if it was, it is fairly large (134cm in MOR 008 vs 141cm in sue), but honestly the 1.5m skull length figure could be referring to any measurement of the skull, not necessarily the smallest.
About AMNH 5027: I wouldn’t go by the looks (I really don’t trust the restored skull shape to be so precise as to exactly distinguish which specimens it resembles most), but a proportionately smaller skull than sue is certainly plausible. On the other hand I doubt that’s going to affect the average size much, since we have to equally consider proportionately longer legs than in sue, so skulls of smaller individuals may be giving conservative estimates, but in exchange the femora are giving upper estimates when scaling both based on sue. But yeah, that’s a valid point.

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kirkseven In reply to theropod1 [2016-08-27 18:07:58 +0000 UTC]

Yeah.. unless it's proportioned like sue or stan
It might actually be longer than sue but I don't
Think it would be heavier.

Just to double check I scaled using Blazes weight estimate for
AMNH 5027 (6.9 tonnes) to match the 12.57 meter estimate and got
8.34 tonnes.so bigger than I expected but still smaller than sue
Whose at 8.4 tonnes going by hartman estimates.

So much smaller than Jack Horners guestimate of 13.72 meters.

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theropod1 In reply to FeatherNerd [2016-08-09 22:11:59 +0000 UTC]

Thanks a lot for those and your kind words!
Your own work is great too!

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FeatherNerd In reply to theropod1 [2016-08-09 23:11:47 +0000 UTC]

Thanks! Also thanks for the watch!!!

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