Re: A Whole Bunch Of Questions

["Jordan Mallon" <j_mallon@hotmail.com>]

> From: "Ivan Kwan" <dino_rampage@hotmail.com>

> 1) Sail or Muscle???
>
> In _Suchomimus_, there seem to be some pretty tall neural spines on the 
> vertebrae above its hips... is there evidence for either a sail or for a 
> hump of muscles? It does seem interesting that most of us still prefer to 
> see our spinosaurs & ouranosaurs with sails instead of humps... what 
> evidence is there for these dinosaurs not to have humps? (I still prefer 
> mine with sails thank you.)
>
> Same with _Acrocanthosaurus_... would it have a low sail along its neck & 
> back or just a huge bunch of muscles?

I was just discussing this very same topic with Jaime the other day...
As it turns out, neither are very big fans of the hump hypothesis.  While 
Jack Bailey makes a decent argument for muscular humps in tall-spined 
dinosaurs, I'm not so sure he's all too convincing. Jaime pointed out that 
the neural spines, for example, bare no muscle scars, that the distal ends 
are not incrassate, etc.
I've also seen arguments that say _Spinosaurus_ could not have had a dorsal 
hump, otherwise the weight of the hump would have forced the animal down 
onto its front legs; the hands and wrists of which were not built for 
walking on.

> 4) Hadrosaur necks
> I've noticed a few hadrosaur restorations where thelong thin neck is buried 
> under this thick neck just like that of a horse's. I've also seen this 
> trend in a few of Greg Paul's artwork and in the silhouettes of his 
> skeletal reconstructions. Personally, I think my hadrosaurs look better 
> with thin necks, but hey, what do I know? But anyway, does the evidence 
> point towards thin necks, thick ones, or somewhere in between. Does 
> Leonardo the _Brachylophosaurus_ tell us anything?

> From what I've heard, Leonardo supports the idea of neck somewhere in 
between the swan-like and horse-like reconstructions we're used to seeing.

> 5) Hadrosaur skin
> I often notice that many restore hadrosaurs with a thin frill of skin along 
> their necks & backs. I've also seen an equal number of hadrosaur 
> restorations with a row of bumps or spines along the back. Do the hadrosaur 
> mummies or skin impressions point to either one being more plausible than 
> the other? I've always thought that a dorsal frill would be subject to much 
> damage through abrasion, sharp vegetation as well as failed predator 
> attacks.

I think that "dorsal frill" you refer to has been attributed to an 
_Edmontosaurus_ specimen.  I'd be curious to know more about this, too.

> 6) _Parasaurolophus_
> While we're on hadrosaur skin, is there actually evidence that 
> _Parasaurolophus_  possessed a flap of skin that extended from the end of 
> its crest down along its neck or is it purely conjecture (& a stroke of 
> artistic license?)

Still artistic licence, so far as I know.

Jordan Mallon

Undergraduate Student, Carleton University
Vertebrate Paleontology & Paleoecology

Website: http://www.geocities.com/paleoportfolio/
AIM: jslice mallon

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