Camel necks: condyles don’t reach the cotyles
April 2, 2013
Long, long ago — back in 2010! — Gordon Dzemski of the University of Flensburg, Germany, sent me a copy of a miniposter that he had prepared, and invited me to share it on SV-POW!. Somehow, it fell through the cracks, and I never did so. Time to fix that!
First, the highlight: a X-ray of a camel neck:
The great thing about this is that the condyles and cotyles are so thickly coated in cartilage that the condyles don’t even reach, let alone nestle inside, the cotyles. Amazing.
Now in contrast, the condyles of horse cervicals do nestle in their corresponding cotyles — very neatly. And the distressing thing is that, to the best of our knowledge, there are no osteological correlates that would allow us to distinguish these conditions. That is, nothing about the naked bones of the camel and horse that would let us infer this huge difference in their cartilage.
Unless anyone knows different?
(Of course, here at SV-POW!, we have previous with camels: the Cambridge camel, all the camels, the Oxford camel, the Paris camel)
Anyway, here is the whole of the poster that Gordon prepared:
And here is his own commentary on it:
Hi Mike,
for your nice Blog and the never ending story of articulated or disarticulated camels, giraffes, goos or ostrichs necks I have made a nice overview of some x-ray pictures of my work.
I think we can postulate some basic principles:
1) There is in every mammal an invertebral disc space between the neck vertebrae.
2) Every mounted skeleton of an animal with a free space between the cotyle-condyle joint system is in articulated postion (but without an invertebral disc).
3) The joint capulse with the specific system components of invertebral discs, cartilage, ligaments and tendons are capable of great dorsoventral and lateral flexion and is capable of high pressure or great tensile force to reach/generate the postures of the living animal neck . And yes, the space beween the camels vertebrae can be 30 or more mm.
4) For prehistoric animals we can assume an average invertebral disc space of 5% of the neck length. I think it is the best guess so far.Please use the picture and this email freely for your Blog if it is in your opinion.
I am inclined to think that the 5% estimate for extinct animals may be a little on the high side (for reasons that will become apparent in due course) but all the evidence is that it’s in the right ballpark.
This has implications.
Sauropod Vertebra Picture of the Week 
April 2, 2013 at 4:46 pm
This is the Cervical Indipendence Day!
April 2, 2013 at 6:55 pm
I really think it is time for X-ray machines big enough for complete, articulated camel and giraffe necks ;)
April 2, 2013 at 7:17 pm
Heinrich,
You just need an industrial CT scanner, of the sort they use to scan jet engines.
April 2, 2013 at 7:20 pm
Yep – where are the much-vaunted corporate sponsors when you need them?
April 2, 2013 at 7:28 pm
Neck? Pfft. We need scanners big enough for the whole darned giraffe.
So how does one go about acquiring these corporate sponsors we keep hearing about, I wonder?
April 2, 2013 at 7:29 pm
BTW., I am pretty sure John H.’s CT-scanner at the RVC would be good for a whole giraffe neck, so long as it was straight.
April 2, 2013 at 7:30 pm
not for a living giraffe, though!
as for the sponsors: pretend your research can be used as ammo in the climate change wars, for the polluters ;)
April 2, 2013 at 11:59 pm
I know that some cetacean workers have successfully been able to use US military CT scanners to look at large baleen whale heads (see http://www.deseretnews.com/article/590045211/A-whale-of-a-CT-scanner.html?pg=all. These same scanners should be able to do what you want. They have a couple here in Utah at Hill Air Force Base. And the skull of Tyrannosaurus rex specimen FMNH PR 2081 (better known as “Sue”) was scanned by Boeing, I believe.
April 3, 2013 at 12:05 am
I was so disappointed when I read that link and found it was only a baby baleen whale. A one-meter head? Bah.
Still, though — not wholly contemptible. For a mammal.
April 3, 2013 at 1:19 am
But note that they used their “small” CT scanner to scan it!
April 4, 2013 at 12:05 pm
I have no experience/knowledge about vertebrae, mammals or biomechanics whatsoever, and I’m afraid my comment will be completely redundant, but couldn’t the different cotyle/condyle relation of horses (relative to camels or any other vertebrate) have anything to do with lateral/axial movements of the head relative to the neck (e.g. move it side-to-side and rotate it along the axis of the neck instead of up-down)? I imagine a camel having a more flexible neck, even relative to it’s length. This is more or less stated in the quote, I guess…
Perhaps a way of checking this is to look for muscle attachments on the cotyle/condyle complex and perhaps on the shoulder blades/ “shoulders” (the parts which are involved in these kinds of movements at least). Also, a calculation of cartilage compressibility could be fun?
This undoubtedly has been done before – as I stated, I’m a vertebrate noob :p
April 4, 2013 at 12:20 pm
Simon, your suggestions all sound good to me. One of things about being a noob is that you often don’t appreciate how much work has not been done before, and how many questions remain to be asked, let alone answered. You would scarcely credit how often Matt and I, in trying to understand sauropods, go looking for analogous work on extant animals and find that it doesn’t exist.
November 8, 2013 at 8:37 am
[…] In the horse, the condyles are deeply inserted into the cotyles of the preceding vertebrae; but in camels, they don’t reach even the lip of the cotyle. This should worry us, as horse and camel cervicals are grossly similar, and no osteological […]
November 8, 2018 at 12:17 pm
[…] that doesn’t fossilise. Consider for example the difference between horse necks (above) and camel necks […]
January 28, 2021 at 11:09 am
[…] Now, some caveating. Zhang et al. (2018) report two different lengths for most the cervicals: a maximum centrum length, which includes the anterior condyle, and a “minimum centrum length” without the anterior condyle. Reporting cervical lengths minus the condyle is fairly common–Janensch did it for what is now Giraffatitan (“ohne condylus”), McIntosh (2005) did it for the AMNH Barosaurus, Tschopp and Mateus (2017) did it for Galeamopus pabsti, and so on. In the freely available but as-yet-not-formally-published 4th chapter of my dissertation, I referred to the length without the condyle as the “functional length”, and I explicitly assumed that it was “the length that each vertebra contributes to the total neck length”. At the time I assumed that condyles were always fully buried in cotyles in life, because I didn’t know about camel necks (see Taylor and Wedel 2013b: fig. 21 and this post). […]