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Re: Kickboxing Cassowary (funny)



I currently think perhaps dromaeosaurids used their ungual more in the
sense of modern Neornithes (i.e., kicking each other during mating,
killing snakes, defending from predators by kicking, etc.) than to
bring down dinosaurs larger than themselves, which is less likely the
primitive function for digit II pedal ungual in Neornithes.

Isn't it a bit overdesigned for that?

I said in other thread that Deinonychus teeth were relatively small,
as in Archaeopteryx, so that it seems difficult for it to tear pieces
of the prey to later swallow. They do not seem to have powerful jaw
musculature as to tear out the flesh from the prey. At least, that
state of things seem to fit better with the dromaeosaurs killing prey
not much larger than themselves.

"Velociraptorine" teeth (those found in most dromaeosaurids in the broad sense) do look well suited for cutting (as opposed to tearing), being strongly compressed mediolaterally and having rather fine serrations. They were, however, most likely too short, recurved and fragile for chomping down on prey that can put up a fight. This is why current textbook wisdom says they used their claws to kill prey and their teeth just for eating.


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

*Archaeopteryx* teeth are different again: few, widely spaced, really small, and conical -- there's just a bit of cutting edge near the tip. This does indicate small prey in comparison to head size -- and fits the fact that the claw on the 2nd toe of Archie is not enlarged.

Now, if dromaeosaurs were actually relatively slower than other, more
cursorial coelurosaurs (Ostrom 76'), because of the relatively short
metatarsus, and if they can not fly (whether primarily or secondarily
non-flyers, although I lean towards the first), I suppose it would be
more important for them to defend when facing a predator, and so to
use claws more defensively than offensively. After all, defense may
explain most enlargements of pedal unguals in non-avian Dinosauria
(e.g., Therizhinosauridae, Iguanodon, "prosauropods") as well as the
cassowary.

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