Re: Suchomimus vs Baryonyx: Dare to Compare

["M.Alan Kazlev" <akazlev@kheper.auz.com>]

tlford@ix.netcom.com wrote:

> Betty Cunningham wrote:
> >
> > Have Suchomimus' feet been found?
> > Did it show any special adaptations such as a wideing of the foot
> base?
> >
> > I ask becasue if this was piscivorus and lived in a sort of
> "crocodilian
> > niche" it seems awful heavy to go wandering around in mud on a mere
> two
> > feet and I'm wondering if it's feet were either hippo-like in being
> big
> > broad blunt shapes, or if they seemed like they were possibly webbed
>
> > like modern waterfowl.  We've seen that the skin on the HANDS of
> > hadrosaurs could modify skin around the fingers to some sort of
> knobby
> > walking mitt, and I'm wondering if the skin on the FEET could have
> been
> > as specialized.
> >
> > Has it's tail been found?
> > If it were as much a swimmer as a crocodile is, wouldn't we find the
>
> > tendon fusion  of the tail reduced from the conditions of say,
> > Deinonychus so the tail would not be as rigid right at the base of
> the
> > spine.   The 'wave' that goes through the body of a swimming animal
> > would be greatly reduced if the tail were as immobile for a section
> as
> > seen in  Deinonychus.  (picture of the 'wave' of the spine of a
> swimming
> > lizard here: I used it as reference for a swimming crocodile I've
> just
> > completed:  http://faculty.vassar.edu/~jolong/swimming.html )
> > Here's a great article on dolphin spine flexibility when considered
> as a
> > swimming locomotor:
> > http://faculty.vassar.edu/~jolong/discsum.html   So if we got fused
> > tendons in the tail for any great length it wasn't no natural
> > swimmer......
> >
>
> A few other things to consider.
>
> Some say Suchomimus/baryonyx caught fish like a bear,

I have always thought the bear analogy strange.  Quoting Greg Paul (who
makes a very good point here)"no living land animal as gigantic as
spinosaurs survive on fresh-water fish alone.  Even brown bears d so
only during the brief and intense salmon runs through narrow mountain
streams..."
[Predatory Dinosaurs of the World, p.271]


> using it's large thumb claw. Why? When the head has a longer reach,
> the claw would be
> inefective. Then it caught fish with his mouth.

yes, the crocodile analogy sounds more logical - crocodiles of course
grew to spinosaur size.  However the metabolism is different - crocs are
ectotherms, whereas spinosaurs like other theropods would have probably
been quasi-endothermic adults (and fully endothermic during the rapid
growth phase when young).

In fact, all crocodile anologues - phytosaurs, champsosaurs,
cochleosaurs, eryopids, etc were *all* ectothermic

> Lets examine this. We have to play the picture all the way through.
> Sure
> it has a skull that looks similar to that of a ghavial. But the
> nostrals
> are still on the side of the skull and not the top,

which *does* seem to mitigate against a semi-aquatic life-style

> so it didn't float like a ghavial. It couldn't swim like a ghavial.
> The whole body
> ungulates, not just the tail. So we rule out swimming to catch a fish
> (it would have to have been a deep river, lake, to begin with). So it
> stood up to it's belly in a river. The rivers bottom would have to
> have
> been hard or it would have sunk into the mud. IT would have to have
> fast
> reflexes to catch the fish. The water would have to have been clear
> for
> it to see the fish. A 6 foot fish swiming in 6 feet of water is
> awfully
> shallow for it. The biggest fish usually are at the deepest part of
> the
> lake/river.
>
> So I say no fish eater. What did it eat then? Terrestrial animals of
> course.

*but* then why the elongated snout and conical (fish-eater) teeth?The
whole beast is an enigma!

[snip]

> I can't see Torvosaurs being close to Spinosaurs.

certainly the accepted paradigm is that the Spinsoaurs are cousins to
teh Megalosaurs (Torvosaurs).  But accepted paradigms have been wrong
before...

>

[snip]

> Why ignore Dilophosaurus? It has a premaxilla very similar, though
> fewer
> teeth, to Baryonyx. The maxilla is long, and could easly be streatched
>
> to that of Baryonyx or Suchomimus.

Yes, Greg Paul argues that the Spinosaurs are late surviving
Dilophosaurs

> A long skull, big claw, a fish eater dosen't make. The WHOLE animal
> needs to be looked at.
>
> Tracy



--
Kewl!   :-)

M.Alan   Proteus   CyBeRrDeWd

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