|
Post by fleshanthos on Sept 22, 2009 16:56:33 GMT
In his Hawaiian shirts.
|
|
|
Post by foxilized on Sept 22, 2009 21:30:42 GMT
I AIN'T A FREAK, YOU'RE A FREAK Actually I AM afreak. But I am a handsome freak. ;D
|
|
|
Post by foxilized on Sept 23, 2009 6:17:23 GMT
Besides that Knight painting, have you ever seen any other artwork (some book or something) of sauropods on 2 feet BEFORE the 80's?
|
|
|
Post by sarcasmosaur on Sept 23, 2009 8:13:31 GMT
Pretty sure Bakker was drawing 'em in the 80's.
Dunno about before then.
|
|
|
Post by Griffin on Sept 23, 2009 16:18:29 GMT
|
|
|
Post by fleshanthos on Sept 24, 2009 0:27:59 GMT
Bakker seems to be pretty good at studying anatomy and deriving a conclusion based on it. I searched for my copy for about 20 mins before realizing I'd lent it to my cousin.
Will read up on his conclusions later, but I recall he compared a Sauropod (don't recall which ones) to a mechanical crane - and compared it to the rearing ability of an elephant at he same time.
Having done a University course in comparative vertebrate anatomy myself, I do think that comparing animals biomechanics should give some very real insight into the likely cases for loooonnnng extinct species.
|
|
|
Post by stoneage on Sept 24, 2009 1:16:37 GMT
Charles R. Knight "Diplococus restored. The largest creature that ever roamed the earth (cover Illustration), in: Scientific American, vol 96, no. 24 (June 15,1907) p485. 1899 Osborn "There is a traditional view that these animals were ponderous and sluggish. This view may apply in measure to Brontosaurus. In the case of Diplodocus it is certainly unsupported by facts." Osborn in addition proposed a novel function for the tails which he thought could function "as a lever to raise the entire forward portion of the body upwards. Thus the quadrupedal Dinosaurs ocassionally assumed the position characteristic of the bipedal dinosaurs--namely, a tripodal position. This I believe is the begining of the Tripod Sauropod position.
|
|
|
Post by Griffin on Sept 24, 2009 2:17:58 GMT
Wow thats a great find Stoneage.
|
|
|
Post by fleshanthos on Sept 24, 2009 16:36:23 GMT
Heh - a 102 yr old depiction is INDEED form the stone age! HAHAHAHAHAHAHAHAHA....
|
|
|
Post by foxilized on Sept 25, 2009 1:01:49 GMT
Well that was the one I meant, great find anyway stone. Apparently that idea of Osborn and Knight wasn't taken too seriously, cuz my point is it wasn't repeated until probably the 70's. It was buried and forgotten (just like happened with the "hot blooded" Laelaps painting) until the "reinassance" of the dinos in the 70's revisioned them and made them popular at last. That in fact was the point of this thread, just for paleoart history reasearch: knowing if that painting was the origin, and if it was continued at any point before the 70's, or not.
|
|
|
Post by foxilized on Sept 25, 2009 22:07:04 GMT
BTW, any of you guys who really know scientific facts (you know I feel very ignorant, actually, about the modern beliefs), which are the species that actually are supposed to be able to do it?
Not the Brachio...
Plateosaurus, still?
Diplo, Apato and the rest?
|
|
|
Post by Griffin on Sept 26, 2009 1:39:31 GMT
Any diplodocid is supposed to be able to do it. Plateosaurus and the other prosaropods as well.
Brachiosaurus probably could not.
The rest I am unsure of.
|
|
|
Post by Horridus on Sept 26, 2009 14:35:14 GMT
Any diplodocid is supposed to be able to do it. Plateosaurus and the other prosaropods as well. Didn't a 2007 study decide that some prosauropods had to be bipeds as they couldn't pronate their hands (that old chestnut)? The study particularly looked at Plateosaurus and Massospondylus, as I remember. Still, only the one study...
|
|
|
Post by Griffin on Sept 26, 2009 15:25:38 GMT
Any diplodocid is supposed to be able to do it. Plateosaurus and the other prosaropods as well. Didn't a 2007 study decide that some prosauropods had to be bipeds as they couldn't pronate their hands (that old chestnut)? The study particularly looked at Plateosaurus and Massospondylus, as I remember. Still, only the one study... Oh yeah I forgot I heard about that. I don't know how true it is though.
|
|
|
Post by fleshanthos on Sept 27, 2009 14:49:44 GMT
Given that the forelegs could reach the ground alot easier than is apparent in lets say hadrosaurs, it seems pretty unlikely that pronation of hands was impossible. This is a guesstimate. I would need to see the study; it needs to be examined to see if it is a valid conclusion or not. I didn't see anything apparently limiting in a CAST of ONE Plateosaurus that I didn't examine in detail.
So.
Study required!
|
|
|
Post by stoneage on Sept 27, 2009 17:13:29 GMT
The basal sauropodomorph dinosaurs Plateosaurus and Massospondylus are often portrayed as habitual quadrupeds that were facultatively bipedal. Surprisingly, the functional morphology of their forelimbs has rarely been considered when reconstructing their locomotor habits. If Plateosaurus and Massospondylus were efficient, habitual quadrupeds we predict that the manus would have been pronated such that it produced a caudally directed force in parallel with the pes. We articulated and manipulated the forelimbs of Plateosaurus, Massospondylus and several extant outgroup taxa (Varanus, Alligator, Anser and Struthio) using a standardized protocol. Moreover, we compared our results with previously published estimates of forelimb movement in saurischian outgroup taxa from Theropoda and Sauropoda and with the basal sauropodomorph/sauropod Melanorosaurus. Our results indicate that the range of motion in the forelimbs of Plateosaurus and Massospondylus did not allow efficient, habitual quadrupedal locomotion. The range of humeral flexion and abduction is limited and the articular surfaces of the radius and ulna orient the palmar surfaces of the manus medially in semi-supination. Active or passive pronation of the manus was not possible and the manus could not function in a dynamically similar way to the pes for efficient quadrupedal locomotion. Our results also rule out specialized forms of quadrupedal locomotion, such as the knuckle-walking gait of some mammals. We suggest that most known "prosauropod" trackways were probably not made by animals such as Plateosaurus or Massospondylus, but the ichnotaxon Otozoum may have been created by animals similar to these taxa. Furthermore, we show that trunk and limb ratios do not yield consistent results and should not be used solely to determine posture. Although these two taxa probably assumed a quadrupedal posture as hatchlings, we show that the morphological orientations of the forelimb elements remained consistent across ontogeny, precluding efficient, quadrupedal locomotion at any age. As with theropods, forelimb use in basal sauropodomorphs is difficult to reconstruct and interpret. We speculate that the forelimb could have aided in acquiring vegetation or defence in Plateosaurus and Massospondylus only if these animals reared or assumed a tripodal posture.
|
|
|
Post by Horridus on Sept 27, 2009 17:39:05 GMT
And that's us told.
|
|
|
Post by fleshanthos on Sept 28, 2009 15:04:01 GMT
I like the Abstract - what paper is it from?? seems at odds with:
Do they mean other Sauropodomorphs than Plateo/Masso ? Or are these included?
What forelimbs, exactly, did they articulate? Fossil bone? Plaster casts? Soft plastic casts with even softer simulated joint articulation? Did they accurately scan and model the bones/muscles/ligaments/tendons into a computer using several specimens???
I need to see the methodology and materials used section....
|
|
|
Post by stoneage on Sept 28, 2009 21:38:10 GMT
I like the Abstract - what paper is it from?? seems at odds with: Do they mean other Sauropodomorphs than Plateo/Masso ? Or are these included? What forelimbs, exactly, did they articulate? Fossil bone? Plaster casts? Soft plastic casts with even softer simulated joint articulation? Did they accurately scan and model the bones/muscles/ligaments/tendons into a computer using several specimens??? I need to see the methodology and materials used section.... www.paleontologia.pl/forum/viewtopic.php?t=1077This is all I have and I assume possibly incorrectly that it is an abstract of the 2007 Bonnan study. If you can find answers to your questions let me know.
|
|
|
Post by Megaraptor on Sept 28, 2009 21:48:38 GMT
Pffff. I want to color mine green, or possibly orange or red, because pink is so not my color. Oh wait this thread is about sauropods isn't it Uh Why aren't there any Dicraeosaurus toys, do I need to sculpt my own or what? You don't need to sculpt your own, I can do that. Once I figure out how.......
|
|