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Re: Triceratops defence, w/added stuff
At 08:51 AM 6/14/99 -0500, Andy Farke wrote:
>To me, it seems that all of the "evidence" for Triceratops herding is
>non-existant, based only on the "extant phylogenetic bracket" approach. Bone
>beds are known for Chasmosaurus, Torosaurus, Pachyrhinosaurus, Einiosaurus,
>etc., implying *but not proving* herding. ...
In my opinion, the phylogenetic bracket is not really useful for herding,
since among extant herbivores there is considerable difference in herding
behavior between closely related forms.
Now, I would be surprised if _Triceratops_ didn't remain in at least small
groups, at least part of the year. But that is a pretty weak statement.
>And, herding may only have been seasonal, for mating, migration, etc. I
>should point out here that evidence for ceratopsian migration is
>circumstantial at best, based on Pachyrhinosaurus material found in Alaska
>and Alberta. Whether these are even the same species of pachyrhinosaur is
Also, given the situation at the time, east-west migration would have been
more likely. A change in altitude of a few thousand feet is equivalent
to many hundreds of miles in the north-south direction. Denver is
mid-temperate, a mere 20 or so miles outside of Denver is a boreal-type
forest of spruce and fir, and a handful of miles beyond *that* is a tundra.
Since the Rockies had already started to form by the Late Cretaceous, even
though they were less high than now, this west would have been the shortest
May the peace of God be with you. firstname.lastname@example.org