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Sauropod Necks. How much do we really know?. Almost nothing, it turns out. Mike Taylor University of Bristol dino@miketaylor.org.uk Matt Wedel Western University mathew.wedel@gmail.com. Why sauropod necks matter. Sander and Clauss 2008:fig. 1. The Berlin Brachiosaur.
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Sauropod Necks How much do we really know? Almost nothing, it turns out. Mike Taylor University of Bristol dino@miketaylor.org.uk Matt Wedel Western University mathew.wedel@gmail.com
Why sauropod necks matter Sander and Clauss 2008:fig. 1
Sauropod neck skeletons are misleading for three reasons. 1. Incompleteness
The Berlin Brachiosaur Giraffatitan brancai MB.R.2181 (HMN SII) Janensch 1950b Plate VIII
The Berlin Brachiosaur Giraffatitan brancai MB.R.2181 (HMN SII) Janensch 1950b Plate VIII
The Carnegie Diplodocus CM 84 & 82 Hatcher 1901 Composite from Plate III
The Carnegie Diplodocus CM 84 & 82 Hatcher 1901 Composite from Plate III
The Carnegie Diplodocus CM 84 & 82 Hatcher 1901 Composite from Plate III
Hatcher 1901 Plate I
The Carnegie Apatosaurus CM 3018 Gilmore 1936 Plate XXIV
The Carnegie Apatosaurus CM 3018 Gilmore 1936 Plate XXIV
Taphonomy of Sauroposeidon Wedel et al. 2000
Gilmore 1925, plate X Baby Camarasaurus
Sauropod neck skeletons are misleading for three reasons. 1. Incompleteness 2. Distortion
The Carnegie Diplodocus CM 84 & 82 Hatcher 1901 Composite from Plate III
Why distortion? Wedel 2005
Sauropod neck skeletons are misleading for three reasons. 1. Incompleteness 2. Distortion 3. Absent cartilage
51cm 41cm +25%
Not likely as much as 25% because a baby giraffe is: A. a baby (though SII is also subadult) B. not a dinosaur How much cartilage does a domestic turkey have in its neck?
255 mm turkey neck Articulated vertebrae are 226 mm long => must add 12% to bone-only length
Domestic turkey Anterior articulation
Domestic turkey in ONP 16º
Domestic turkey Synovial joint extends centrum length by 12%
Domestic turkey in true neutral pose 44º
Domestic turkey neutral poses 28º difference
760 mm adult ostrich neck Articulated vertebrae are 701 mm long => must add 8% to bone-only length (Matt Cobbley, pers. Comm.)
Were sauropod necks more like Those of giraffes or birds? Birds are more closely related. BUT gross vertebral morphology is more like that of giraffes, e.g. opisthocoelous articulations.