[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

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

On 12/12/06, jrc <jrccea@bellsouth.net> wrote:

Also, I find the following overall patterns suggestive. Simplified, the
sequence goes; 1). a class appears, reaches maximum size, then disappears.
If the disappearance is not catastrophic, they dwindle in size. 2). New
class appears, reaches maximum size that is _less than the preceding class
maximum_, then dwindles gradually in size. This exact pattern is the rule
(since the mid-Jurassic, anyway), not the exception, for terrestrial
animals. Dwindling giantism, generally, seems to be the rule in the
terrestrial record (insects, amphibians, reptiles...).

------Interesting.  The very largest pterosaurs were present at the very end
of the Cretaceous, so apparently the rule doesn't hold for them.

Doesn't seem true for dinosaurs either - the biggest theropods, the biggest ornithischians, and most of the contenders for biggest sauropod, are Cretaceous.

Andreas Johansson

Why can't you be a non-conformist just like everybody else?