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Post by Pangolinmoth on May 4, 2009 3:25:47 GMT
Here's some info. From early on there has been speculation by Osborn and others that sauropods could reach up on hind legs, using their tail as the third 'leg' of a tripod (somewhat like kangaroos), and a famous restoration of a Barosaurus rearing up on hind legs in the American Museum of Natural History illustrates this hypothesis well. One study postulated that if sauropods had adopted a bipedal posture at times, there would be evidence of stress fractures in the forelimb 'hands'. However, none were found after examining a large number of sauropod skeletons. If a sauropod stood in the tripod posture, there would be a heavy weight load on the haemal spines on part of the tail. As the sauropod got heavier as it grew, when it reared, these haemal spines would have to carry more and more load, until some of them would break due to stress fracture, and that would make rearing painful and the sauropod would have to stay on four feet after that. That may have evolved as a safety measure to prevent rearing when it got too heavy for rearing to be safe. There are reports of such haemal spine fractures being found in sauropod tail vertebrae.  Pangolinmoth what you say is true but there's a lot more to it. Robert Bakker speculated in his "Dinosaur Heresies", that the Herbivores of the Late Jurassic all fed high in the trees, probably because Sauropods had such long necks. However he also proposed that Stegosaurs who had almost no neck did the same. He said they did this by using the Tri-pod position (two rear legs and tail as a third leg). He also claimed these Dinosaurs died out because the high vegetation died out. Furthur he claimed that the herbivore Dinosaurs of the Cretaceous took over because they were low browsers. What he didn't know at that time was that the Sauropods didn't die out all over the world, and many lived in the Late Cretaceous. One of the problems is that Sauropods are incredible heavy like Elephants, Hippos and Rhinos, even more so. Elephants can stand on their two hind legs in the circus but seldom do in the wild preferring to keep all four legs on the ground. I've never seen a Hippo or Rhino stand on two legs. Also many Sauropods were mounted in museums early on showing a swan like neck position. In order to obtain this position it was neccessary to break neck vertebrae. Scientist later discovered that the necks of Sauropods were stiff and not very flexible. Most Sauropods couldn't raise their necks much above their shoulders. Which would mean they probably feed closer to the ground. Also this would make it difficult to move around in a forrest because their long necks would keep running into trees as they turned and they couldn't raise it up around trees. Even Brachiosaurs which are generally shown as having giraffe like necks have been questioned. Kinto (Favorite) Dinosaurs show Brachiosaurus with a rather straight forward neck to illustrate this idea. We can't even be sure that the haemal spine fractures found in some sauropods were caused from trying to stand on their tails or something else. In conclusion there still is much speculation and debate on this topic. And seeing how there is many different types of sauropods which probably ate different foods at different heights the debate is likely to continue.  Well put Stoneage. I like to think that they could. I think I agree with the idea that up until a certain age it was possible. |
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Post by Dan on May 4, 2009 5:51:01 GMT
And what exactly has been postulated regarded the purpose of neck length? I haven't been following the sauropod theories of late, though I remember Crichton claiming long necks could act as a counterbalance for long tails, which could be used as weapons (not that it was really his place to postulate such things).
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Post by kuni on May 4, 2009 8:44:00 GMT
A large neck means the sauropod has more potential food it can access(by swinging the neck from side to side) without having to move its entire body. If it had a really short neck, it would have to take a step every time it ate all of the plants in front of it.
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Post by Dan on May 4, 2009 17:07:41 GMT
Really? Long necks have a number of inherent problems for the animal, though. Minor energy conservation seems like a rather small advantage.
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Post by stoneage on May 4, 2009 22:32:36 GMT
Really? Long necks have a number of inherent problems for the animal, though. Minor energy conservation seems like a rather small advantage. Unless of course you weigh 20 tons are more! ;D |
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Post by Dan on May 4, 2009 22:41:29 GMT
True, but then we know little of their metabolisms.
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Post by [][][]cordylus[][][] on May 4, 2009 23:41:15 GMT
Didn't they have a half-bird half-reptilian type metabolism? I think I read that somewhere. … And that they would need an avian air-sack type system to breathe properly ;D
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Post by bokisaurus on May 4, 2009 23:43:56 GMT
Very nice collection   Go sauropod fans Go! ;D Yah, I think I need to find a better way to display my long necks ;D |
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Post by piltdown on May 5, 2009 0:38:05 GMT
Very nice collection Go sauropod fans Go! ;D Yah, I think I need to find a better way to display my long necks ;D Do what I do, buy a coffee table and place all the large sauropods in the middle of the living room ;D  *sigh* And I wonder why I don't have a social life  ;D |
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Post by tetonbabydoll on May 5, 2009 0:41:45 GMT
Hmmm, I wonder if I can et away with that....? Susan my "accidently" remove them to parts unknown...   |
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Post by bokisaurus on May 5, 2009 2:27:53 GMT
Very nice collection Go sauropod fans Go! ;D Yah, I think I need to find a better way to display my long necks ;D Do what I do, buy a coffee table and place all the large sauropods in the middle of the living room ;D *sigh* And I wonder why I don't have a social life ;D LOL! ;D ;D ;D If I only have a big living room ;D |
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Post by stoneage on May 5, 2009 3:20:24 GMT
Didn't they have a half-bird half-reptilian type metabolism? I think I read that somewhere. … And that they would need an avian air-sack type system to breathe properly ;D Actually this is all debatable. I'm too tired to talk about it now. Maybe later.  |
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Post by piltdown on May 8, 2009 0:56:51 GMT
I wasn't intending to do so, but while I was buying big lots for the Kaiyodo and similar sauropods I got hold of a few Kaiyodo theropods, and was sufficiently interested in them to keep them. Alas, I have now succumbed to the collector mentality and am now busily chasing down chase figures and special figures and repaints Here's a pic, there's still dozens more to go, but they'll be in my grasp very soon The Battat is present because even with the Kaiyodos it's still the second-best mass produced tyrannosaur around  Unfortunately to make way for the theropods the pterosaurs and ornithischians have almost all disappeared. The tyrannosaurs were hungry and ate them all ;D |
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Post by [][][]cordylus[][][] on May 8, 2009 1:01:56 GMT
What's the megalania doing there?!
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Post by piltdown on May 8, 2009 1:03:36 GMT
Honorary theropod ;D I just like overgrown meat-eating lizards  |
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Post by [][][]cordylus[][][] on May 8, 2009 1:07:07 GMT
I thought it was another guard dog or something ;D
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Post by bokisaurus on May 8, 2009 1:08:16 GMT
I wasn't intending to do so, but while I was buying big lots for the Kaiyodo and similar sauropods I got hold of a few Kaiyodo theropods, and was sufficiently interested in them to keep them. Alas, I have now succumbed to the collector mentality and am now busily chasing down chase figures and special figures and repaints Here's a pic, there's still dozens more to go, but they'll be in my grasp very soon The Battat is present because even with the Kaiyodos it's still the second-best mass produced tyrannosaur around Unfortunately to make way for the theropods the pterosaurs and ornithischians have almost all disappeared. The tyrannosaurs were hungry and ate them all ;D Ah, the inevitable fate of all species specialist! Sooner or later, something will just pull yah and before you know it, BOOM! Your collection have doubled! hay naku, nakakatakut na yan! ;D ;D Did some of your pterosaur migrate to deanm's collection perhaps? Nice collection, BTW. I know, one of this days I will photograph my Kaiyodo collection, too ;D |
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Post by piltdown on May 8, 2009 1:37:31 GMT
I thought it was another guard dog or something ;D Eh, Tyrannosaurus rex doesn't need a guard ;D Though I did get a few Kaiyodo andrewsarchuses to help herd the sauropods ;D |
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Post by deanm on May 8, 2009 1:42:59 GMT
Alas, not yet... I would lovingly adopt the strays... At deanm's home for wayward pterosaurs "all are welcome"
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Post by piltdown on May 8, 2009 1:48:40 GMT
Alas, not yet... I would lovingly adopt the strays... At deanm's home for wayward pterosaurs "all are welcome" Alas, I spoke to the Quick rhamphorhychus and he told me he prefers the climate here in Vancouver ;D |
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Pangolinmoth what you say is true but there's a lot more to it.
![[][][]cordylus[][][] Avatar](http://files.sharenator.com/Troll_Face_U_MAD_RE_wrestling_1-s407x405-126802.jpg)
Go sauropod fans Go! ;D
;D 
