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Re: A problem of cartilage
Short answer: No problem of cartrilage. We provide for cartilage,
as is apparent to even casual inspection.
Shorter answer: just jump to the bottom of this post, where I quote
from Joe's boss (click the link to hear) "I'm not arguing that with
Short peek: To confirm that I leave space between condyle and
cotyle, I include below URL's to some representative ONP
reconstructions (with the thumbnails and higher-resolution images
paired below). Note that I sometimes use transparency to clearly
indicate that the condyle inserts only partly into the associated
Three diplodocids (thumbnail below; higher resolution versions
elsewhere on site):
Longer answer for GSP and others concerned about providing for
cartilage in ONP reconstructions.
1) My ONP restorations do include spacing for substantial cartilage.
The size of the gap is based on a substantial number of samples
across actual sauropod necks that are in articulation in situ. These
include ventrally-exposed diplodocid neck series in relief up on the
wall of DNM, and specimens such as DNM 28 (which is in storage on
pallets at BYU) and the USNM Camarasaurus neck (also on pallet, only
partly prepared), and Barosaurus lentus CM 11984 (likewise only
partly prepared) and many others we have personally poured over and
measured and photographed. In all: the central articulations are
tightly spaced. Obviously there is a gap, and I do not naively
restore them as if there no intervertebral cartilage. As my ONP
digital photo-composites reconstructions clearly show, I provide for
an appropriate intervertebral gap.
2) The gap between condyle and cotyle in articulated sauropod
cervical series scales roughly proportionally to the condyle radius.
3) regarding the AMNH 5761 specimen, the one where GSP says "Kent is
still trying to argue that 5761 cervicals 11 & 12 are fused
straight. He is not going to win this one." We should start off in
heartfelt agreement with the observation that there is indeed a bit
more (vertical) gap between the underlying foam cushion and the
condyle of C11 than below the rim of the cotyle of C12 (which rests
on the foam). That's because the condyle is SMALLER in diameter than
the cotyle. Get it? Let me go through the reasoning: A) condyles
fit inside cotyles, B) cotyles have an inside and an outside diameter
(the rim has a thickness), C) the cotyle inside diameter is larger
than the condyle diameter to provide for said cartilage. Therefore,
the cotyle outside diameter is necessarily a bit larger than the
associated condyle diameter. How much bigger? Oh, about the amount
the condyle of C11 is above the foam :) I'm not arguing that with you.
4) We find that at most just a bit of the ball is visible between the
raised ridge of the condyle (where the synovial capsule would have
attached) and the posterior of the cotyle, at least for the caudal
end of the cervical series. Look at the illustration of Euhelopus
(you can find it on my site) and see how tightly articulated the
centra are preserved. Look at Janensch's illustration of the block
containing C10-D2 of _Brachiosaurus brancai_ specimen SII:
5) GSP didn't understand my caution regarding compositing a vertebral
series out of discrete illustrations, commenting "Since all the 3108
cervicals are on the same figure at the same scale and appear to
articulate with one another it is hard to see how there is a scaling
issue." Since this seems to be an earnest attempt to understand why
his exercise with tracing paper resulted in a gopher-hunter, and the
same illustrations turn out more biologically plausible in my ONP
reconstructions, I re-reiterate that one cannot trust that just
because the publication says the illustrations are all 1/10 scale, or
whatever, that they in fact ARE all published to the correct scale.
With Janensch, great care seemed to be given to the printing of
illustrations of the original material (with the exception of the
skeletal reconstruction :), but with the diplodocids in Hatcher and
Gilmore, there are small discrepancies in scale (carefully measure
total centrum length in the illustration, multiply that length by the
purported scale value and compare what you get with the published
textual values for that length). The individual images are not all
printed at precisely the same scale, which can lead astray those that
just cut (or trace) and paste. Trust but verify.
6) Finally, regarding GSP's remarkable proclamation: "No modern
mammal feeds higher than giraffes because what with dental batteries
and big brains they are too big headed to be so long necked"
I can only respond:
"I have no response to that"
from the movie "Joe versus the Volcano". Listen at:
And more generally, about going on and on about sauropod necks, I
wish to sign off by quoting (from the same movie):
"I'm not arguing that with you! "I'm not arguing that with you! "I'm
not arguing that with you! Who told you that? ... if I said that I'd
be wrong ... No! I told you that! Me! What? Maybe. Maybe.