Plesiosaur Day, 18 November 2004 - Some notes on the meeting
Mike Everhart
Sternberg Museum of Natural History, Fort Hays State University, Kansas, USA
Other topic suggestions:
What were they eating? (let's pay special attention to stomach contents and a possible change in habits from the Jurassic through the Cretaceous)
An old, yet unanswered question: What was the role of gastroliths? ….do they occur regularly in any group besides elasmosaurs? What is their earliest occurrence?
What can we say regarding the range / mobility of elasmosaurs from the probable source of their gastroliths versus where their remains are found? (Elasmosaurs found in western Kansas are several hundred kilometers from the nearest sources of such stones)
When did pliosaurs go extinct worldwide? Our last pliosaur in Kansas (Brachauchenius) dates from the Middle Turonian.
Mike Taylor
Selected comments:
I should also observe that I found it a surprisingly difficult job doing
a recent limbs review paper with Hans Thewissen (I did the tetrapods other
than mammals). Although I managed to 'use up' most of my remaining unpublished
functional morphological thinking, and clear that side of my desk, so
to speak, I did not enjoy doing this paper, as I found, rather counterintuitively,
that the marine reptiles were by far the most difficult part. I came to
feel that one of the problems with plesiosaur (and marine reptile generally)
work is that the swimming side of matters is sometimes - not always, but
sometimes - being taken that bit too far. And, in fairness, I have to
say that I now find my 1987 ichthyosaur swimming paper horribly simplicistic.
I was left feeling that if I ever have the opportunity and the time I would like to collaborate with a real modern hydrodynamics expert to give all this marine reptile swimming stuff a good critical review.
MAT plesioprojects 29.9.04
In press
J. G. M. Thewissen and M. A. Taylor. Aquatic adaptations in amniotes [limbs]. In B. K. Hall (ed.) From Fins to Flippers. University of Chicago Press.
Already 'started' but still in gestation - if sometimes the blastocyst is under delayed implantation …
M. A. Taylor, A. R. I. Cruickshank and L. F. Noè. Design for torsion in tetrapod skulls: the case of twist-feeding pliosaurs (Plesiosauria: Reptilia). (This discusses the use of geodesic lines of tension and compression, and how they are not pure helices but are modified by beam loadings.)
M. A. Taylor, L. F. Noè and perhaps G. W. Storrs. The marine reptile fauna from the lowermost Lias (Rhaetian, Late Triassic, and Hettangian, Lower Jurassic) of Street, Somerset. Also published and in press/preparation, papers on various collectors of Street marine reptiles.
M. A. Taylor. Bristol Institution ichthyosaur and taxonomic problems of Ichthyosaurus latimanus.
In the longer term
M. A. Taylor. A review of Scottish marine reptile material as acquired by NMS in recent years - mostly fragmentary and mostly Upper Jurassic (and much of it not plesiosaurian). Likely to produce lots of worthy but short, even itsy bitsy, papers - nothing very revolutionary at first glance.
Proposed MSc student project with Mike Benton
Dorset County Museum plesiosaur (?pliosaur) with gastroliths.