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Just How Did Sauropods Defend Themselves?

  • 07-12-2011 8:05pm
    #1
    Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭


    Allosaur wrote: »
    It's my opinion that in nature, one doesn't have to be fast. One just has to be fast enough.
    BTW did that make them any less agile?

    Anyway, interestingly enough
    http://theropods.blogspot.com/2011/04/theropod-speed-and-locomotion-part-ii.html

    Put Deinonychus at 30-40Mph. That is four time plus faster than most people.
    Not slow.

    Now the bigger you get the slower you go, it puts Giga- at 10ish Mph. However one wonders how fast Argentinasaurus moved. My bet is that it wasn't all that zippy.

    I have always thought that sauropods are too often depicted as very slow animals with very slow reflexes, just waiting to be bitten by some passing theropod. In documentaries you always see the theropod taking a big bite and the sauropod just moaning in pain. It's rather sad. I have always imagined them as being much faster than usually believed, and by faster I don´t mean they were runners; simply that they could turn around quickly to face an enemy, that they had quick reflexes and that a theropod had to work hard to actually take a bite, and not only that, but doing so would be extremely dangerous. Sauropods are very underrated IMO.


Comments

  • Registered Users Posts: 128 ✭✭Allosaur


    Adam Khor wrote: »
    I have always thought that sauropods are too often depicted as very slow animals with very slow reflexes, just waiting to be bitten by some passing theropod. In documentaries you always see the theropod taking a big bite and the sauropod just moaning in pain. It's rather sad. I have always imagined them as being much faster than usually believed, and by faster I don´t mean they were runners; simply that they could turn around quickly to face an enemy, that they had quick reflexes and that a theropod had to work hard to actually take a bite, and not only that, but doing so would be extremely dangerous. Sauropods are very underrated IMO.
    I'm in two minds about it.
    Firstly the projected mass of these animals is about or at least near the limit of what we think that bone and muscle could support. And that was just in normal motion and/or standing still.
    If you put that mass in motion, the forces excerted must have been enormous. A quick demonstration of the principal:
    Put a 12ft ladder on your shoulder, turn around. About 1/2 way through the turn, try and reverse it's direction......

    For even such a comparitivly small and light object the resistance is very noticible, and it takes a lot longer to slow down than it did to speed up.n Imagine scaling that up to the lenght and weight of a sauropod neck and tail. Don't even start me on the centrifugal force at the head end when it swung it's neck. G-LOC would be a factor methinks...Unless it's arteries and veins could constrict like a g-suit, or provide a seperate pulsing action to augment the heart in getting the blood all the way out there.. (my head hurts and I'm just thinking about it).

    But having said that, obviously they could move and had some defence. Otherwise, they just served as a huge all-you-could-eat buffet for anything and everything...

    I just can't begin to understand how.:confused:


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    Allosaur wrote: »
    I'm in two minds about it.
    Firstly the projected mass of these animals is about or at least near the limit of what we think that bone and muscle could support. And that was just in normal motion and/or standing still.
    If you put that mass in motion, the forces excerted must have been enormous. A quick demonstration of the principal:
    Put a 12ft ladder on your shoulder, turn around. About 1/2 way through the turn, try and reverse it's direction......

    For even such a comparitivly small and light object the resistance is very noticible, and it takes a lot longer to slow down than it did to speed up.n Imagine scaling that up to the lenght and weight of a sauropod neck and tail. Don't even start me on the centrifugal force at the head end when it swung it's neck. G-LOC would be a factor methinks...Unless it's arteries and veins could constrict like a g-suit, or provide a seperate pulsing action to augment the heart in getting the blood all the way out there.. (my head hurts and I'm just thinking about it).

    But having said that, obviously they could move and had some defence. Otherwise, they just served as a huge all-you-could-eat buffet for anything and everything...

    I just can't begin to understand how.:confused:

    Well, I know jack about physics and whatever, but I know a bit about nature, and for what I've seen, nature doesn´t care about whatever limitations we humans think it has. Remember when they said Pteranodon was the top limit for a flying creature, size-wise, and that anything larger would be completely unable of taking off? And even, that Pteranodon itself was too big to take off from the ground and had to throw itself from a cliff?
    Well, enter Quetzalcoatlus, Hatzegopteryx (same thing?) and all those giant azhdarchids, some of them the size of friggin giraffes. They were probably about half a ton in weight- much, much larger than Pteranodon, and guess what? They could fly. Probably not as well as Pteranodon, but still, paleontologists had to swallow their words about "upper limits".
    They also used to say that anything bigger than Brachiosaurus would simply collapse, but now we have Argentinosaurus, Alamosaurus, Sauroposeidon...
    Non prehistoric examples also abound.

    So I think that, if sauropods grew to those immense sizes, it is because they could, because they evolved adaptations to make sure that such sizes wouldn´t be a hindrance. They are among the longest-lived dinosaur linneages, they were around from the late Triassic to the latest Cretaceous. You don´t survive that long among formidable giant theropods unless you are perfectly able of defending yourself.


  • Registered Users Posts: 128 ✭✭Allosaur


    Adam Khor wrote: »
    Well, I know jack about physics and whatever, but I know a bit about nature, and for what I've seen, nature doesn´t care about whatever limitations we humans think it has. Remember when they said Pteranodon was the top limit for a flying creature, size-wise, and that anything larger would be completely unable of taking off? And even, that Pteranodon itself was too big to take off from the ground and had to throw itself from a cliff?
    Well, enter Quetzalcoatlus, Hatzegopteryx (same thing?) and all those giant azhdarchids, some of them the size of friggin giraffes. They were probably about half a ton in weight- much, much larger than Pteranodon, and guess what? They could fly. Probably not as well as Pteranodon, but still, paleontologists had to swallow their words about "upper limits".
    They also used to say that anything bigger than Brachiosaurus would simply collapse, but now we have Argentinosaurus, Alamosaurus, Sauroposeidon...
    Non prehistoric examples also abound.

    So I think that, if sauropods grew to those immense sizes, it is because they could, because they evolved adaptations to make sure that such sizes wouldn´t be a hindrance. They are among the longest-lived dinosaur linneages, they were around from the late Triassic to the latest Cretaceous. You don´t survive that long among formidable giant theropods unless you are perfectly able of defending yourself.
    It's the "understanding how" bit I'm having a problem with.
    Phill Manning in Dinosaur CSI did a demonstrative piece on it. The methods were questionible, but the science was well founded. Take a look and you'll see what I mean.


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    I'm in the "Screw your physics!" camp on this one. There's just no way they could have survived for so long in so many places if they were simply big mushrooms waiting to be eaten. many had whips, clubs or spikes on their tails. these were clearly used for defensive purposes.
    Perhaps their awkwardness was a secret advantage? Flailing around wildly at random and smashing any adversary foolish enough to get too close.


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    Galvasean wrote: »
    I'm in the "Screw your physics!" camp on this one. There's just no way they could have survived for so long in so many places if they were simply big mushrooms waiting to be eaten. many had whips, clubs or spikes on their tails. these were clearly used for defensive purposes.
    Perhaps their awkwardness was a secret advantage? Flailing around wildly at random and smashing any adversary foolish enough to get too close.

    Thing is, being huge is already a huge advantage, because most predators prefer not to attack a creature that looks too tall and massive. Lions are capable of hunting elephants but they very rarely do so, simply because elephants look too big and scary.
    Now imagine a sauropod armed with a long dangerous tail (a flesh-slicing whip in the case of Diplodocus and co), a long neck (which means it could reach and bite you, I don´t know why no one ever thinks of this- I've asked paleontologists and they agree that sauropods, regardless of how weak their jaws were compared to other dinosaurs, would have a nasty bite nonetheless), huge forelegs that could crush you (or stab/slash with those sidewards pointing spurs/claws?)... doesn´t sound harmless to me at all.


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  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Adam Khor wrote: »
    a long neck (which means it could reach and bite you, I don´t know why no one ever thinks of this- I've asked paleontologists and they agree that sauropods, regardless of how weak their jaws were compared to other dinosaurs, would have a nasty bite nonetheless),

    Littlefoot's Mother gave that a go in TLBT, but thought better of it when Sharptooth's bite was much bigger.



  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,646 Mod ✭✭✭✭Capt'n Midnight


    The best comparison I've heard of for a suaropod's tail is imagine someone swinging a telegraph pole at you

    wasn't Ankylosaurus' club about the same weight as a person ?


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    The best comparison I've heard of for a suaropod's tail is imagine someone swinging a telegraph pole at you

    wasn't Ankylosaurus' club about the same weight as a person ?

    It wouldn´t surprise me if it was even heavier than your average person...

    I'm thinking most dinosaurs (except perhaps for ceratopsians) used their tails as defensive weapons... almost no one ever imagines giant theropods, for example, using their tails to hit enemies, but even crocodiles and monitor lizards (whose most obvious weapons are their teeth) will lash out at enemies with their tails.
    I don´t buy the usual "the tail would break" argument.

    As for sauropods, I feel like I should mention once again the infamous Amphicoelias brontodiplodocus paper, which may have been wrong about almost everything but did point out that the tail of Diplodocus seems to have had a series of keratinous blades that probably made the tail not a simple whip, but a flesh-slicing weapon of doom, similar to those martial arts metal whips but moved by a monstrously powerful animal.
    31NgENQuNTL._SS500_.jpg

    diplodocus-pastori.jpg

    Imagine what it could do to an enemy! The Shunosaurus tail-club and similar ones (like Spinophorosaurus) would be variations on the same theme, but equally nasty...


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    is the idea of sauropods rearing up on their hind legs completely mooted now?

    barosaurus_43798.jpg


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    Galvasean wrote: »
    is the idea of sauropods rearing up on their hind legs completely mooted now?

    barosaurus_43798.jpg

    I read somewhere that titanosaurs and brachiosaurs probably didn´t rear up due to being heavier/having a more rigid spine and body, whereas diplodocoids were very well suited for rearing up (and even as you know, some say baby diplodocids could run on two legs). Their tail was also adapted to support weight. So the famous Barosaurus female rearing to protect its young would be perfectly plausible :D


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  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Adam Khor wrote: »
    I read somewhere that titanosaurs and brachiosaurs probably didn´t rear up due to being heavier/having a more rigid spine and body,

    :eek:

    jp-brach.jpg&sa=X&ei=GLDrTur-AY2XhQf48qDACA&ved=0CAwQ8wc&usg=AFQjCNENJFIx1N9OKOZyfuZp4j5qAv0xbw

    :(


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    Galvasean wrote: »
    :eek:

    jp-brach.jpg&sa=X&ei=GLDrTur-AY2XhQf48qDACA&ved=0CAwQ8wc&usg=AFQjCNENJFIx1N9OKOZyfuZp4j5qAv0xbw

    :(

    I never really understood why the Brachiosaurus reared up in JP... it didn´t become much taller at all! :D But it made for a nice scene.

    Hey, and who knows? Elephants aren´t particularly flexible animals either and they do rear up:

    2797501571_9068be0881.jpg

    They also do stuff like this (not that they do it in the wild, but they CAN do it, that's my point):

    pic_1067.jpg
    (And yes, I do think these kind of acts are cruelty)



  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Hoo-hah!!!!


    brontomerus.jpg&sa=X&ei=F0PuTt_yHpOxhAeqyvWoCA&ved=0CAwQ8wc&usg=AFQjCNEp0durAqGImhEr05k5qrBI1bH6FQ
    astro-big.jpg&sa=X&ei=dEPuTp-2HcOnhAfu0tmrAg&ved=0CAwQ8wc4Jg&usg=AFQjCNHEvNBBa0UI1hXLQEewUcBDUBXL-Q
    sauropod1.jpg&sa=X&ei=kUPuTs_zGIO0hAeLm9jGCA&ved=0CAwQ8wc4Jg&usg=AFQjCNHUx2AP_yXvfD_ybxXaYaJDcov2bQ
    thunder_thighs.jpg&sa=X&ei=sEPuTp7LFdOyhAfApti9CA&ved=0CAsQ8wc&usg=AFQjCNGwNuqZkDTCIOJ2zBQ3pL1pY2Z7KA


  • Registered Users Posts: 128 ✭✭Allosaur


    Hypothetically speaking (AKA "Pulling this out of my arse") an animal that large shouldn't need to move fast to do damage. If kinetic energy is deffined by the mass times the acceleration of an object, then the amount of kinetic energy in even a slow moving sauropod tail would be tremendious due soley to the weight of the thing.

    It's the same reason why a glacier doesn't need to move fast in order to carve out a valley.

    "But the theropod could get out of the way".

    Yes he could. - That's the point though isn't it...

    ANd the job is made more difficult for your average theropod if they are attacking hearding animal. If the whole heard responds (like a flock of birds for example) then I'd imagine it would be very difficult to get close enough to injure anything significant.

    In preditor / prey interactions the trick to survival is not to be the quickest, healthiest, or best protected. The trick is not to be the slowest, sickest or most vulenable. It's often enough just to make the preditors look somewhere else for a meal.


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    images?q=tbn:ANd9GcSyBbAl0edveSy2i1sJrsl_WSSR3YubB5Sc0gilNIzG__ibgOfz5y_wPgL3


  • Moderators, Science, Health & Environment Moderators Posts: 5,279 Mod ✭✭✭✭Adam Khor


    Galvasean wrote: »
    images?q=tbn:ANd9GcSyBbAl0edveSy2i1sJrsl_WSSR3YubB5Sc0gilNIzG__ibgOfz5y_wPgL3

    Perfectly plausible IMO. Just because their teeth weren´t particularly adapted for biting other animals doesn´t mean they couldn´t deliver a nasty bite anyways (think tapir, horse, donkey, human...)

    Plus look at this:

    Tapuiasaurus+macedoi+2.jpg

    5365890329_bb7188a6ef.jpg

    camarasaurus.jpg
    Tendaguru-brachiosaur-skull-Dave-Hone-Nov-2011-tiny.jpg
    If those things weren´t good for biting...


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Certainly wouldn't stick my hand in there to test out the idea...


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