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retirement as Secretary-General of IGCP last
April.
She made a fleeting visit to Edinburgh,
Reading, Newcastle and Jurmala in
September 99. In Edinburgh she spoke about
the Lower Carboniferous tetrapod-bearing
assemblage in Queensland. Allen & Unwin
have just brought out a paperback called
"Wizards of Oz - Recent breakthroughs by
Australian scientists" by Peter Spinks and
Anne Warren and Sue are in it for the
discovery of the Carboniferous tetrapods!
Most exciting so long as the powers that be
read it and give us more money!!
In Jurmala Sue showed some of the arctic
remains from Somerset Island and Timan. In
between she delved in museum drawers at
BGS and RSM Edinburgh and the Hancock
Museum.
Papers of note:
Turner S. 1999. Early Silurian to Early
Devonian thelodont assemblages and their
possible ecological significance. In Boucot,
A.J. and Lawson, J. (eds.).
Palaeocommunities: case studies in
International Geological Correlation
Programme 53, Project Ecostratigraphy,
Final Report. Cambridge University Press,
Cambridge. 42-78.
Turner S. (1999): Non-gnathostome
vertebrates: In R. Singer (ed.),
Encyclopedia of Paleontology. Fitzroy
Dearborn Publishers. 2 volumes; 1700 p.
Chicago.
Turner, S., Kuglitsch, J.J. and Clark, D.L.
1999. Llaandoverian thelodont scales from
the Burnt Bluff Group of Wisconsin and
Michigan. J. Paleont., 73(4):667-676. (SEE
THE COVER!!)
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Below a small digression upon which I have
pondered long and hard:-
THE IMPORTANCE OF COPROLITE EVENTS
S. Turner : Ichthyolith Issues20.
HAS anyone else wondered seriously
about how much we owe to the vertebrate
digestive system to preserve really important
information about the evolution ofour
ancestors? With my propensity for finding
coprolites (and sometimes not much else) I
have often given the matter deep thought.
Well, I think we should elevate the humble
coprolite to the position it deserves. I
suggest here that we should seek out the
characteristics of Palaeozoic and other fish
coprolite-bearing horizons, which I propose
here to designate Coprolite Events (as a
belated contribution to IGCP 216 perhaps -
with apologies to Otto Walliser).
These phosphatic deposits are event
horizons crowded, nay overwhelmed by fossil
ordure or coprolites (Reviews see e.g.
Häntzschel et al. 1968, Duffin 1979, Thulborn
1991). Palaeozoic horizons where coprolites
begin to be noticeable (i.e. fish have got to a
reasonable size and perhaps begin schooling)
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do not occur until the Early Carboniferous
according to Daphne Sumner's (1994) review.
She illuminated us on the large numbers of
coprolites throughout the West Lothian Oil-
Shale Formation, Lower Carboniferous
(commonly in the transition zone between the
East Kirkton Limestone and the overlying
Little Cliff Shale) which is a case in point.
She also noted other horizons, in particular,
the Pumpherston Shale at South Queensferry
near Edinburgh (even I managed to collect
some from here - S.T. coll. in Hancock
Museum - courtesy of a fine day out with
Stan Wood) - all Viséan. She noted other
similar Carboniferous horizons (Price 1927,
Johnson 1934, Zidek 1980). Johnson's (1934)
horizon may be a significant stratigraphic
event horizon being found by him in Colorado
and by Price (1927) in West Virginia at
approximately the same age in black shales
of the so-called Weber Formation; the
copious coprolites occurring in a zone about
23 m thick. Johnson and Price ascribed their
coprolites to "ganoids" but given their spiral
nature, chondrichthyans would be a more
likely source. Does anyone else have
evidence of this Late Carboniferous
phosphatic hey day. Were Zangerl &
Richardson's (1963) examples from the same
time?
BUT significant coprolitic horizons do also
occur in much older deposits: the Telychian
fish beds of Lesmahagow in Scotland and
New Brunswick, Canada, for example. Here
presumed coprolitic masses and strings have
yielded some of the best-preserved thelodont
scales. The source of these coprolites is
thought tobe invertebrate, arthropod and
possibly eurypterid or phyllocarid. Gilmore
(1992) had a deal to say about other spiral
coprolites in the Late Llandovery of Scotland;
Ritchie (1963) also noted these. Gilmore saw
his specimens as originating from thelodonts
with a spiral valve, as in chondrichthyans.
At the first IGCP 328 meeting at Parc de
Miguasha in 1991, Jim McAllister enthralled
us with an account of the coprolites from the
Late Devonian (early Frasnian), Escuminac
Formation (McAllister 1996). Then there are
amazing examples possible in the late
Famennian Cleveland Shale (e.g. Williams
1972, Briggs & Crowther1990, McAllister
1985). Waldman (1970) prized open a
Cretaceous coprolite to the same good effect
finding Lepisosteusscales and other remains
in a presumed crocodilian coprolite. He
emphasised something I have been trying to
maintain since the beginnings of IGCP 328 -
that most palaeoecology etc. has been based
on macrovertebrate evidence and that
microvertebrates have been neglected or
ignored, giving what Waldman calls an
unbalanced or a "top-heavy" approach.
So vertebrates got into the weighty
business much earlier than Sumner's
contention implies and equally significantly by
Early Silurian times. BUT I know of no really
good Ordovician event - can anyone
enlighten me?
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