Also, ground cover IS extensive today and there is evidence of that for
the past as well: e.g., over 400 types of fern pollen from the Morrison
alone. Why then, show barren ground (and this goes beyond just
Henderson's art)?
That is quite an impressive showing of pollen diversity. Certainly, it
would seem that ground cover must have been common in many locations
(and I would actually say that Doug Henderson's illustrations depict a
great deal of ground cover in many cases, though some of his more well
known works are 'bare ground' terrain). However, I am curious how much
ground cover we should expect in some of the depositional environments
that are reconstructed. My paleobotanical knowledge is limited so I am
curious to what extent pollen diversity records are thought to
correlate with living biomass.
Also on the general note of paleobotanical records, I am curious
whether or not there is any fossil evidence for significant epiphytic
biomass during any portions of the Mesozoic. (There is, after all, at
least one epiphytic cycad living today, so perhaps the Jurassic
included more such taxa).