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Re: Kickboxing Cassowary (funny)



David Marjanovic wrote:

> Isn't it a bit overdesigned for that?

If it performs well those missions, it would be good enough. I see
three refinements in dromaeosaur unguals: a) large relative size, b)
curvature, c) cutting edge. All these can function well for stabbing a
biting small mammal, lizard, or Protoceratops juvenile. Many mating or
defensive weapons are relatively large (not to talk about horns).

> "Dromaeosaurine" teeth (found in Dromaeosaurinae or some subset thereof --
> dromaeosaurid phylogeny is currently a mess), on the other hand, are similar
> to tyrannosauroid ones.

That may hold for Dromaeosaurus, but the fact that teeth in other
moslty complete dromaeosaurs are small (Deinonychus, Velociraptor)
indicates we should not extrapolate the habits of Dromaeosaurus as
suggested by its teeth to the other dromaeosaurs were the teeth are
not equally developed.

Just in case, I was not saying that the teeth should be great to kill
the prey, just for tearing it apart once death (or not) for the sake
of swallowing a piece of meat. For tearing pieces of a large prey
apart teeth are commonly large (in scanvenging or predatory birds
there is a great tooth-like process in the tip of the bill for that
sake). I say you need relatively large teeth. The relatively short
postorbital region of the dromaeosaurid skull suggests the abductor
musculature was neither great thing as to tear off chunks. This also
happens in Cathartes, but at least it has "tooth-like process in the
bill" and expects other carnivores to break the hide before eating. It
would be strange for a predator to have to wait for a larger predator
to cut the hide of its prey.

> *Archaeopteryx* teeth are different again.

True, but I only say Archaeopteryx that it resembles them in having
small teeth (or at least, some nearly complete dromaeosaurs such as
Deinonychus and Velociraptor), and small teeth does not suggest big
prey. The small-toothed jaws would make the jaws in these dromaeosaurs
approach a cutting function, as that of the tomial border in bird
ramphothecae, instead as of those with somewhat larger teeth to grasp
a chunk of flesh (were however cutting is also welcome, but larger
teeth are necessary for the biting not to be quite superficial).

> Makes sense, except that none of your examples have sickle-shaped claws.

Why would sickle-claws not to be cutting for defense? a cutting border
might help penetration. I suspect you refer to this aspect, as the
ungual is quite curved in prosauropods.