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and Gram's stain, which can detect
keratin, are also useful.
Positive controls may include hard
tissues from vertebrate and invertebrate
fossils from the same localities, as well as
skeletal material from fish and amphioxus.
Additional controls could involve
conodonts that are subjected to light
etching instead of decalcification, and the
staining of undecalcified elements. The
method does not work well on elements
that are still embedded in matrix.
This technique makes it possible to
localise organic residues to defined
tissues in the conodont that are still in a
natural position. The stain is not a surface
deposit, but soaks into the hyaline tissue
and leaves the albid tissue that is
exposed on the surface unstained.
Although molecules such as collagen
are widespread in the Animal Kingdom, it
is unlikely that any of the stains are in
fact specific for particular protein residues
in the fossil material. They are simply
deposited in regions of high organic
content. Nevertheless, the presence of
hydroxyproline in many species of
unaltered conodont element is an effective
demonstration that hyaline tissue is high
in collagen in the original unfossilised
state, and therefore unlikely to be a form
of vertebrate enamel. No organic residues
appear to be present in the albid tissue,
and this is therefore unlikely to be a form
of vertebrate bone.
Kemp, A. & Nicoll, R.S. 1996. A
histochemical analysis of biological
residues in conodont elements. Modern
Geology 20. 287-302 [reprinted in MG
21, 197-213 with 2 colour plates].
Savage, N.M., Lindorfer, A. & MacMillen,
G.E. 1990. Amino acids from Ordovician
conodonts. Courier Forschungsinstitut
Senckenbverg 118, 267-275.
*****************
Richard J. ALDRIDGE, Professor of
Palaeontology, Head of Department,
Department of Geology, The University,
Leicester LE1 7RH, U.K.
Phone: 0116 252 3610
Fax: 0116 252 3918
E-mail: ra12@leicester.ac.uk
Palaeobiology in the UK does pretty well at
the moment. Ivan Sansom and Phil
Donoghue have both just been given
Lectureships at Birmingham, and we have
appointed Sarah Gabbott to a Lectureship in
Leicester. Derek Briggs was elected FRS. As
far as my current students go, Kim Freedman
is in the very final stages of writing up(look
out for her taphonomic study of Jamoytiusin
Palaeontology) and Steph Barrett is getting
some interesting new results out of sectioning
conodonts. I have a new student starting in
September, but he will be working on
acritarchs.
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Papers of interest:
Donoghue P.C.J. & Chauffe, K.M. 1998.
Conchodontus, Mitrellataxisand
Fungulodus: Conodonts, fish or both?
Lethaia31: 283-292.
Donoghue P.C.J., Purnell, M.A. & Aldridge,
R.J. 1998. Conodont anatomy, chordate
phylogeny and vertebrate classification.
Lethaia. 31:211-219.
Donoghue P.C.J.,Forey, P.L. & Aldridge, R.J.
2000. Conodont affinity and chordate
phylogeny. Biol. Rev. 75, 191-251.
Fascinating stuff! - ed.
*********
Mark PURNELL, Department of Geology, The
University, Leicester LE1 7RH, U.K.
Is now on the permanent staff at Leicester.
Purnell M.A. 1999. Scenarios, selection, and
the ecology of early vertebrates. In Major
Events in Early Vertebrate Evolution:
Palaeontology, Phylogeny and Development.
A joint Systematics Association / Natural
History Museum meeting 8-9 April 1999, p.
25.
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Handbook of PaleoichthologyVolume 4.
Chondrichtyes III Holocephali
Where to order
Verlag Dr Friedrich Pfiel
Wolfratshauser Str. 27. D-81879
Ph: 49 89 7428270, fax: 49 89 7242772.
E-mail: 100417.1722@compuserve.com
****************************
The Encyclopedia of
Paleontology.
edited by Dr Ron SINGER
Published by Fitzroy Dearborn Publishers. 2
volumes; 1700 p. Chicago.
ISBN 1-884964-96-6
includes papers on fossil fish by several of
our group - e.g., Burrow, Gagnier, Janvier,
Kemp, Long, Sansom, Turner, Young
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