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Re: The timing of stegosaur extinction
Since it looks like nobody more knowledgeable than I got this mail correctly
displayed (it has no line breaks), I'll try...
----- Original Message -----
From: "Joe Cantrell" <email@example.com>
Sent: Monday, February 14, 2005 6:28 PM
Subject: The timing of stegosaur extinction
When did the last stegosaurs disappear in North America, South America,
Africa Europe and other regions?
Good question. Usually stegosaurs are rare, and because most, uh,
vertebrates are rare in general, we can't automatically assume that the
youngest fossil coincides with the extinction of the group. -- If I recall
correctly, stegosaurs are known from:
NA: Late Jurassic only, including the last stage of that epoch.
SA: Early Cretaceous only. (The one fossil is still unnamed.)
Africa: Late Jurassic only.
Europe: Middle Jurassic to Early Cretaceous.
Asia: Middle Jurassic to Early Cretaceous.
Probably this means that Stegosauria as a group died out around the end of
the Early Cretaceous. Surprises can't be excluded.
You might have heard of *Dravidosaurus*, which was described as a Late
Cretaceous stegosaur from India... this has turned out to be a badly
preserved bone of a plesiosaur.