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Re: The Biggest Dinosaurs
On Wed, 20 Aug 1997, Thomas R. Holtz, Jr. wrote:
> In fact, during the last eleven million years or so of the Cretaceous of
> western North America, there seems to be a net size increase in most of the
> dinosaur groups. The latest Maastrichtian tyrannosaurids, ceratopsians,
> pachycephalosaurians, "hypsilophodontians", ankylosaurids, and nodosaurids
> are the biggest known for each of those lineages. Furthermore, the average
> hadrosaurids of the latest Maastricthian are pretty big, too, but the
> largest known are from either the early Campanian of Baja California or the
> early Maastrichtian of China.
Are there any best-guesses as to why this mean size increase
occurred? Was there a similar size increase among smaller dinosaurs of
the same time?
Thanks in advance.