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Re: Pterosaur size (Was: Great in the air, not so good underwater)

To me at least, dinosaur body size, for saurischians at least, seems to reach its peak around the Cenomanian/Turonian, with theropods like Spinosaurus, Mapusaurus, and Giganotosaurus and sauropods like Argentinosaurus and Paralititan. Body size seems to decline in sauropods afterward, Bruhathkayosaurus, if a sauropod at all, being an exception. The carnosaurs and spinosaurs appear to go completely extinct at that point for some unknown reason.

What is interesting here is that most of these truly huge sauropods and theropods are from Gondwanaland, suggesting that geographic isolation may have been involved.

Then again, there are lineages that actually decrease in size over the Cretaceous, not just titanosaurs, but dromaeosaurs are another example; compare Utahraptor and Deinonychus from the EK to Bambiraptor and Saurornitholestes from the LK. Though I can't recall exactly when Achillobator lived; that might throw the pattern off.