Re: BITING CERATOP{S}IANS

[Stan Friesen <swf@ElSegundoCA.ATTGIS.COM>]

>From: Tom Holtz <tholtz@geochange.er.usgs.gov>
 > 
 > A few people addressed the problem of open land fossils.  One point I
 > didn't notice (sorry if I missed it) was the fact that, during the
 > Mesozoic, there was no grass.  There must have been some non-forested land,
 > but what vegetation covered that land is hard to say.  Ferns, perhaps.

Ferns certainly formed a significant part of the open land vegetation,
at least where there was sufficient water.

To this day there are places where grasslands would otherwise be
expected that are dominated by ferns (specifically the bracken
meadows of England and New England).

I suspect that "desert" (that is relatively barren vegetation) covered
a wider range of habitats in the Late Cretaceous than it does now, since
grasses are less water-dependent than any of the potential alternatives
I know of from pre-Neogene times.

 > In
 > any case, no pampas, grasslands, or savannahs (by definition) during the
 > Cretaceous.

I pretty much agree, with the caveat that I might use the term
fern savannah to refer to the fern-dominated equivalent of a grass-
land savannah.
 > 
 > >CERATOPSIANS DID NOT FORM DEFENSIVE RINGS
 > 
 > That's mighty absolute of you.  I would agree that substantial evidence for
 > defensive rings is not there, but exactly how would you demonstrate
 > evidence for or against this kind of behavior in the fossil record?

About the only evidence I could think of would be trackway evidence,
and even there, this can only provide positive evidence, not negative.
[Lack of trackways demonstrating such behavior is NOT good evidence,
as the combination of good track preservation conditions with predator
attacks is likely to be extremely rare].


swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.