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Re: Oviraptorids as Parrots?

Dann Pigdon wrote:

Both tiger sharks and jaguars (of all things!) are specialist
testudinate feeders. The sharks use sideways head thrashing to 'saw'
through the shells of marine turtles with their serrated teeth,

Not to contradict Dann, since tiger sharks do find sea turtles very appetizing, and some tiger shark populations do indeed target sea turtles. But I thought tiger sharks were the ultimate nonspecialist predators. Aside from turtles, they'll eat teleosts, sea mammals, reptiles (especially sea snakes), birds, other sharks, molluscs, crustaceans, and the occasional _Homo sapiens_ that happens to be in the wrong place at the wrong time.

In fact, based on anayses of stomach contents, tiger sharks will eat almost ANYTHING that isn't nailed down (including stuff that used to be nailed down - like tyres, license plates, nails, and other trash that somehow ended up in the ocean). Tiger shark teeth appear to be adapted for generalized predation and opportunistic scavenging. The teeth resemble the teeth of certain members of an extinct family of sharks known as anacoracids, which have likewise been argued to be generalist predators/scavengers for this reason.

Sharks preying or feeding on testudinates goes all the way back to the Mesozoic (e.g., cretoxyrhinid tooth marks in protostegid shells; Shimada and Hooks, 2004, J. Pal. 78: 205?210)