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Re: NAPC-96 Washington, June 1996



Tom Lipka wrote:

>I was going to post the same thing question but decided to wait a few more
>days. I am also attending the NAPC-96 and would like to hear from those who
>are attending/presenting as well.  Just out of curiousity, and as an
>_unofficial_ prelude to the abstracts with programs that we all will get,
>would anyone who plans to present or talk about something ( I am) care to
>tell us something about their presentation?  Think of it as a free chance to
>advertize your work! Conversely, if you do not wish to make any public
>statements yet but don't mind telling me or others off list, I would still be
>interested. Maybe even post an abstract?

Ok here is mine.

Title: Early taphanomic history of the Lower Cambrian Emu Bay Shale fossil
Lagerstatte.

The Emu Bay Shale in South Australia, contains a restricted collection of
beasts including trilobites up to 25 cms (10 inches) long, two species of
_Anomalocaris_ and some other Cambrian arthropods.  They are preserved by
red stained, fibrous CaCO3.  One form, _Myoscolex_, however is preserved by
calcium phosphate, with a covering of CaCO3.  Initially _Myoscolex_ was
identified as an annelid and the preserved tissues were recognised as being
muscle tissue.  Recent finds have shown the _MYoscolex_ is preserved as a
'soft-tissue x-ray', the muscles, and only the muscles, are preserved, but
none of the more recalcitrant tissues (cuticle etc).  This reversal of
normal preservation can be explained wrt lab experiments on early
phospatization.

The other interesting thing is that rare specimens of _Myoscolex_ do
preserve some features which bring the annelid classification into
question.
One specimen has a series of flap-like appendages, a few have what appear
to be large eyes, with two specimens showing at least three eyes, two
specimens show what might be a proboscis, and a few specimens show
tergites.  These characters, along with the nature of the cuticle where it
is preserved, suggest an arthropod affinity, more exactly an affinity with
the Burgess Shale vacuum cleaner form _Opabinia_.

OK it isn't vertebrate palaeontology, but I'm the moderator (for one more
day anyway), so wat i sez goes!

Chris

cnedin@geology.adelaide.edu.au                  nedin@ediacara.org
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Many say it was a mistake to come down from the trees, some say
the move out of the oceans was a bad idea. Me, I say the stiffening
of the notochord in the Cambrian was where it all went wrong,
it was all downhill from there.