Plesiosaur swimming reconstructed from skeletal analysis and experimental results
F. Sanders, K. Carpenter, B. Reed, and J. Reed.
Webpage Copyright © 2004-2010 by Mike Everhart
Webpage created 11/10/2004; updated 02/12/2010
LEFT: "Dolichorhynchops in flight" is copyright © 2001 by Russell Hawley.
Those of you who were fortunate enough to attend the talk given by Frank Sanders at the 2004 SVP meeting in Denver, Colorado, saw some very interesting videos of underwater experiments that re-created the probable method by which plesiosaurs swam. For those of you who weren't there or missed the session, Ken Carpenter has graciously provided me a copy of one of the videos (.wmv). Click here to download the file.
The .wmv version of the video file is about 600 kb and may take a while to load if you are on a dial up modem. If you cannot view the .wmv version, you may request a .mpeg version (5.5 Mb) from Mike Everhart
The abstract is shown below and is available as a .pdf file.
PLESIOSAUR SWIMMING .WMV VIDEO
|2004 - Journal of Vertebrate
Paleontology 24(Supplement to 3): 108A-109A.
ABOVE FOR THE .PDF VERSION OF ABSTRACT
SANDERS, Frank, CARPENTER, Kenneth, REED, Brian,
REED, Julia, Denver Museum of Natural History, Denver, CO
Three basic hypotheses have
been proposed for the swimming locomotion of plesiosaurs: rowing motion in which the
flippers move primarily in a horizontal plane; figure-eight motion (underwater flight) in
which the flippers move primarily in a vertical plane while continuously being rotated on
their longitudinal axes so as to generate thrust in a manner roughly analogous to that of
penguins or sea turtles; and a sea lion stroke in which the flippers move downward (and
backward (belly-ward)) to produce thrust. Within these hypotheses various proposals have
been made for synchronicity of the fore and rear flippers, as well as front flippers
propelled while the back flippers were passively employed for stabilization/steering.
These models for flipper motion have not been adequately constrained by limits of joint
articulation of fossil specimens. Furthermore, the proposed models for plesiosaur
propulsion have not previously been experimentally tested; given the inherent complexities
of underwater propulsion it is important that conclusions regarding plesiosaur swimming
should be confirmed by successful physical demonstrations.
(© 2004 Society of Vertebrate Paleontology - Used with permission of the authors)
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