BARYONYX

["Jaime Headden" <jaemei@hotmail.com>]

1: ANALOG

a: BEARS

Okay, so bears are not good analogs for *Baryonyx*. Bears have large 
paws (forget the claws, they weren't used for fishing) that are used to 
literally swipe a salmon from the water. *Baryonyx'* hand was, to put it 
simply, small. Only the "thumb" was large of the whole manus, and we 
have enough of the manus to detirmine this, too. The forelimb was small, 
quite short, whereas bears have very long forelimbs.

A bear does not stand on its hindlegs to fish, it will often lunge after 
those salmon and catch it in its jaws---it does this more frequently 
than "swiping", even juveniles.

How the skulls figure is simple: long, with larger teeth located to the 
anterior withing the jaws. *Baryonyx* has teeth much smaller than the 
anterior dentition towards the back, and this is especially evident on 
the mandible. Bears have teeth typical of the Carnivora: insicors, 
canines, elongate molars with slicing cusps that "shear" as in scissors 
when overlaping. Yes, *Baryonyx'* teeth overlapped, but the form is very 
different, conical, with finely serrated carinae, on all the teeth, 
anterior premaxillary teeth almost angled forward or they _do_ angle 
forward, forming a tooth arrangement that has no parallel, not even 
crocodiles.

b: CROCODILES

Here you have elongate jaws, mostly carinate and occasionally serrated 
conical teeth, but crocodile teeth variate along the jaws, and can be 
large toward the back of the jaws, almost as large as the anterior 
teeth---this is especially evident in the gharial, whose teeth are 
nearly all the same size. Of fisher crocs, the forelimbs are used either 
to walk with, or swim. Now, Baryonyx, hypothetically, could swim, and 
definately could have walked, but the forelimbs were, most likely, not 
used. As above, they were quite small.

Crocodiles, unlike bears, are developed almost to the exclusion of all 
other forms of habitat, to the water, while bears are very varied in 
their place of residence (though all species are excellent swimmers).

2: HABITAT

A developed shoreline, riverbank, or lakeshore as opposed to the 
estuarine or marine habitats gave *Baryonyx* a decided position within 
which to exploit. Of his neighbors, *Megalosaurus* is too incomplete to 
hypothesize about, and *Eustreptospondylus* was seemingly more suited 
for fully terrestrial habitat.

When you're a shoreline animal, you develop certain traits, including 
the swimming ability (the isolated ora or Komodo dragon, *Varanus*, 
could also swim, but was delegated to a forest habitat, with occasional 
forays to the sea to hop the next ride to the other islands it is now 
found on), and a predisposition to aquatic or near-aquatic dietary 
habits (i.e., feeding on those who feed on aquatic fauna or flora, 
though we can probably say with some certainty that *Baryonyx* did not 
eat leaves).

3: THE NOSE

The snout of *Baryonyx*, though often cited as similar to the crocodile 
snout, is actually a near miss for such an analog, as based on several 
features:

i)   external naris located back from tip, top, and back of snout
ii)  orbits located laterally, with some binocular vision
iii) teeth reduced in size towards rear of jaw
iv)  anterior teeth forming "piercing" apparatus actually analagous to 
     a bear-trap*

* = a bear trap functions by setting long blades into the flesh, 
gripping and holding to prevent escape; such was a structure of the 
*Baryonyx* jaws, though true function may be somewhat different.

Okay, so Bary could grab food, and prevent it from getting away, and 
instead of doing this by holding it with the hands, as would many other 
theropods, he could use the jaws instead, and so they were rather large 
and strong. But the fish of the Wealden, for instance, didn't get very 
large, as seen in *Lepidotes*, one of the rare occurances where we know 
_for sure_ a meal (not diet) of a dinosaur.

The snout with the posteriorly-displaced nares could mean that Bary 
could probe the waters without having to splash around a lot and lunging 
after leaping dinner, like certain ursines. This snout, like the kiwi or 
platypus (you heard me, _platypus_!) could function as a probe for muddy 
water or even the muck itself, meaning the food was like the mudskipper, 
oir catfish, who bury themselves, or other aquatic life. The only 
problem with this is that kiwi's and platypi have nares at the tips of 
the their snouts, platypi being able to seal these off.

4: THE CLAW

Unlike raptor claws, the thumb ungual is broad, not compressed, and 
would actually serve as a piercer or grabber than as a blade, for it 
lacks any similarity to slashing blades, as used today or seen in some 
modern animals (certain birds can and will attack by slashing with their 
talons, instead of grabbing, by penetrating and digging in, tearing 
flesh or just raking it painfully, and this is usually defensive 
behavior---sounds like *Baryonyx* could have used intrspecific combat or 
feared larger predators, unlikely as the latter is as Bary could have 
reached over forty feet in length).

Comments are welcome,

Jaime A. Headden

______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com