Re: [asa] Quick Q about coprolite densities

The amount of coprolites varies, but I would say generally they aren't
really
that abundant. We find them sometimes in coal balls where they are
about
the only evidence we have in those fossils of animals. However, it is
only the
occassional coal ball that has them. But if you get a coal ball that
has them,
you are more apt to find more than one.

I seem to remember an oolitic limestone, in which the oolites (balls)
were
originally interpreted to be coprolites. While that made them VERY
abundant
in the limestone, subsequent interpretations suggested they were not
coprolites.

There was an interesting paper analyzing and showing that coprolites in
coal balls
showed enough difference in vegetation matter as to suggest at least two
different
kinds of cirtters.

Coal balls are clacareous nodules that preserved the peat of
Pennsylvanian coal
before it was turned into coal. The preservation of the plant material
is often exquisite.

James Mahaffy (mahaffy@dordt.edu) Phone: 712 722-6279
498 4th Ave NE
Biology Department FAX : 712
722-1198
Dordt College, Sioux Center IA 51250-1697
>>> "Duff,Robert Joel" <rjduff@uakron.edu> 01/09/07 10:44 AM >>>
I was reading about the coprolite mining industry in England in the late
19th century and was amazed by the shear volume of coprolites unearthed
there. Although not all of these nodules where necessarily fossilized
excreta it still got me thinking about the volume of faeces in the
fossil record. Does anyone know of any estimate of volume of coprolites
versus preserved organismal remains or have any general impressions of
how common fecal material is versus other fossils? One location that
came to my mind is the Green River formation. It seems to be loaded
with fish pellets that I imagine might account for many time the mass of
the preserved fish themselves. The reason I am interested is that it
struck me that in the YEC model one would predict that coprolites should
be less common than other fossils (how many time can the animals taken
up by the flood poop in a few days?) especially considering faeces could
have been easily dissolved in a flood while the YEC model considers
animals to have been well preserved.

Joel

--------------------------------------------------------
Dr. R. Joel Duff, Associate Chair

Associate Professor of Biology

185 ASEC, Department of Biology

University of Akron

Akron OH 44325-3908

rjduff@uakron.edu

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Received on Tue Jan 9 13:11:06 2007