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Re: "Bonn Scientists Simulate Dinosaur Digestion in the Lab" (mesozoic grass?)




Of course... It also matters how the sauropods were eating - if they swallowed the plants whole the silica would cause less wear.

Even more to the point: I am not aware of any studies confirming that
Mesozoic era Equisetum contained silicates (and have even seen this question
raised in a couple of works by paleobotanists). This is doubly true for
other forms like the larger Neocalamites and elegant Schizoneura paradox
which may be only very distantly related to Equisitum.

As for "grasses" there *were* plants with morphologically similar forms:
For instance the gnetal Ephedra which today specialises in arid
environments, has a clear fossil record establishing several species in the
Cretaceous and was likely around much earlier.

It is interesting to note that the modern Yucca, despite being a flowering
plant, is morphologically similar to a number of mesozoic Cycads and
Cycadeoids and grows in fireprone habitats today in association with Ephedra
(run a search).

There were also apparently herbaceous (or even possibly ruderal aka. "weedy") conifers in the Mesozoic (run a search for A. stipulare)

Finally, our knowledge of paleobotany appears to suffer from a greater
preservation bias than vertebrate paleontology and receives less attention
(I recall Tiffney stating in the late 90s that almost no work on
plant-dinosaur interactions had been done).

So, assuming it is laging by 40-60 years in some parts of the field
(paleoecology matures later than taxonomy) and everything should be taken
with caution (including the lake of angiosperm grasses in the Cretaceous).

S!

-Jonas Weselake-George


----- Original Message ----- From: "Brian Baziak" <baziak@hotmail.com>
To: <d_ohmes@yahoo.com>; <dinosaur@usc.edu>
Sent: Wednesday, February 06, 2008 12:18 PM
Subject: RE: "Bonn Scientists Simulate Dinosaur Digestion in the Lab"




It may be hard to see, depending on the rate of tooth replacement to the rate of wear. Even then, you may need to see it in teeth still in the skull to know that you have front teeth. I don't know how easy it is to differentiate them in sauropods. We also need to think about what exactly the sauropods are eating, since horses are grazers, and grasslands didn't even exist for saurpods.

Brian

Date: Wed, 6 Feb 2008 08:53:13 -0800
From: d_ohmes@yahoo.com
Subject: Re: "Bonn Scientists Simulate Dinosaur Digestion in the Lab"
To: dinosaur@usc.edu

This was mentioned in reference to the silicates in equisetum, the
excessive wear they cause on teeth.

"However, many dinosaurs did not have any molars at all. They just pulled
up their food and gulped it down." --  innovations report.

Wouldn't silicate wear still be present on the 'front' teeth of any
horsetail eating sauropod? Having seen the effects of armadillo shell on
dog teeth, I can state that wear occurs very quickly (relative to sauro
life spans) in that case.

Don

----- Original Message ----
From: "mkirkaldy@aol.com" <mkirkaldy@aol.com>
To: dinosaur@usc.edu
Sent: Wednesday, February 6, 2008 10:45:46 AM
Subject: "Bonn Scientists Simulate Dinosaur Digestion in the Lab"

"Bonn
Scientists
Simulate
Dinosaur
Digestion
in
the
Lab"
06.02.2008
http://www.innovations-report.de/html/berichte/biowissenschaften_chemie/bericht-102776.html
"Scientists
from
the
University
of
Bonn
are
researching
which
plants
giant
dinosaurs
could
have
lived
off
more
than
100
million
years
ago.
They
want
to
find
out
how
the
dinosaurs
were
able
to
become
as
large
as
they
did.
In
actual
fact
such
gigantic
animals
should
not
have
existed.
The
results
of
the
research
have
now
been
published
in
the
journal
'Proceedings
of
the
Royal
Society
B'."

Mary


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