Hello again, old friend
December 5, 2011
This week the SV-POW!sketeers are off to Bonn, Germany, for the Second International Workshop on Sauropod Biology and Gigantism. All three of us will be there, plus SV-POW! guest blogger Heinrich Mallison, plus Wedel Lab grad student Vanessa Graff, plus about 50 other awesome scientists from around the world. So we’ll have a ton of fun, but we probably won’t get much posted.
In the meantime, enjoy this cool encounter from the bone cellar at the Humboldt Museum in Berlin, where Mike and I fetched up at the end of the last IWSBG back in 2008. It’s a transversely-sectioned dorsal centrum of Giraffatitan, one that Janensch illustrated in his 1950 monograph on the vertebrae of Giraffatitan. Mike and I were very familiar with the cross-section image from the paper, so it was cool and a bit unreal to find the actual item.
Reference
Janensch, Werner. 1950. Die Wirbelsaule von Brachiosaurus brancai. Palaeontographica (Suppl. 7) 3:27-93.
Sauropod Vertebra Picture of the Week 
December 6, 2011 at 10:53 am
Hi there, sorry if this doesn’t fit into the title of this post but this is quite urgent because I couldn’t find ANY articles that discussed about cervical ribs. I Googled and found your article here: https://svpow.wordpress.com/2009/12/02/your-cervical-ribs-are-probably-non-existent/
Not to be confused with transverse processes(those pointing backwards) in chickens which are also called cervical ribs, this are “thoracic lookalike ribs” attached to the 14 cervical vertebrae. It is not fused.
I am studying on the chickens vertebrae for my final year project and no one seems to have the answer. It only appears in a few of the chickens I dissect. Do you what these are and what purpose do they serve? Are they similar to human cervical ribs condition that is said to contribute to cancer?
Thank you!
December 6, 2011 at 11:21 am
Hi, Matt,
There is more on cervical ribs in Veronica the ostrich: right cervical rib #3, but it’s generally true that they are neglected. Not just on SV-POW!, but in the literature generally.
I don’t understand what you mean at all here. Transverse processes don’t point backwards, they point sideways (as the name suggests). The processes that point backwards from the ventrolateral part of chicken cervicals are indeed good, honest cervical ribs, homologous with those of sauropods. They are unfused in very young birds, but fuse to the vertebrae (capitulum to parapophysis, tuberculum to diapophysis) during ontogeny.
If you post some photos of your chicken vertebrae on a public site such as flickr, and then post the URLs here, we’ll be happy to take a look at them for you.
December 7, 2011 at 6:24 am
Hi Mike thanks for the answer!
About the statement above, yeah transverse processes point sideways and spinous processes point upwards so I was actually confused myself because certain books refer to the cervical ribs(those located at the ventrolateral location) as transverse processes. I can’t remember but I think it was by Tankred Koch. I have to check again to be sure.
The cervical rib I’m referring to here isn’t the one mentioned above but rather it is a pair of ‘thoracic-like ribs’ that is attached to the last cervical vertebrae(C-14).
The photos are at home so I’ll post it up once I get home. Thank you for your help once again! :)
December 7, 2011 at 9:38 am
The problem, I suppose, is that the various parts of a vertebra do shade into each other. Properly, a diapophysis is the more dorsal, and the parapophysis the more ventral, of the two articular surfaces that support the ribs; but those terms are often also used to include the processes that those facets are on. These processes are often directed laterally, and so they are sometimes (or at least the one bearing the diapophysis is often) called the lateral process — a term that is more descriptive than nominative.
These terms all make more sense for dorsal vertebrae (= thoracic vertebrae in avian terminology) than they do for the cervical vertebrae, in which the ribs are usually fused to the diapophyseal and parapophyseal processes (so that there are no diapophyseal and parapophyseal facets). I can see why at that stage someone might loosely refer to the whole fused diapophyseal process+parapophyseal process+cervical rib complex as a lateral process. And since the actual rib part that projects backwards is so small in chickens, careless labelling of the whole “lateral process” could give the impression that the rib itself is the lateral process. But it’s not.
[If you’ve not seen it before, I recommend SV-POW! Tutorial 2: Basic vertebral anatomy, and Tutorial 4: Laminae! — and indeed all the other tutorials.]
December 7, 2011 at 10:35 pm
These are the photos I took:
December 7, 2011 at 10:44 pm
Right, those are from right at the cervical-dorsal transition, where things get muzzy. Those two long-thin, posteroventrally directed processes are ribs of a kind. The posteriormost of the two I think is a dorsal rib, since it has an uncinate process. I don’t know chickens well enough to tell you whether the other the the last cervical or the first dorsal (=thoracic).
Anyway, they are not “transverse processes”.
December 8, 2011 at 12:14 am
The first ‘rib’ you see is attached to the last(14) cervical vertebrae. The second rib you see with the uncinate process is the first thoracic rib which is not fused.
The ‘rib’ attached to C-14 is bewildering and some chickens have it while others don’t. I can’t seem to find a definite answer. Do you think these are similar to the cervical ribs that occur rarely in humans but are said to cause cancer?
December 8, 2011 at 7:38 am
I wouldn’t really want to speculate. But if it’s present in some chickens and not in others, then it’s obviously not functionally very important. Individual variation is pretty common in many animals.
December 8, 2011 at 11:38 am
On the topic of gigantism: there is one advantage for a vegetarian animal in being very large. This is that the effect of a toxin in a poisonous plant will often depend on dosage per kilogram. The greater the mass of the animal, the more dilute is the toxin.
In modern tropical forests, most plants are poisonous. Very likely this was equally true when dinosaurs were around.
December 9, 2011 at 5:05 am
[…] previously reported, the lot of us are in Bonn for the sauropod biology workshop. Last night we met up at the welcome […]
December 9, 2011 at 6:17 am
Thanks Mike for taking your time to help me out. Maybe I’ll just include it in my FYP so that more research can be done on this peculiar bone. Thanks again and I find this site really interesting! :)
December 9, 2011 at 6:55 am
Interesting thought, Don. I’d not seen that mentioned before. Do you know if it’s in the literature?
December 9, 2011 at 9:36 am
Obviously larger herbivores need to eat more as well, but the dilution of toxic should still hold if mammals are anything to go by as larger ones generally need to eat less as a proportion of their bodyweight (e.g. the smallest carnivoran, the least weasel, must eat a third of its bodyweight every day and can apparently starve to death in 24 hours).
December 9, 2011 at 8:55 pm
I _think_ this has been mentioned in the literature, but I couldn’t point you to a specific ref. In any case, Odontodactylus is right, the lower mass-specific metabolic rate of big animals and hence lower food requirements per unit body mass should insulate them from toxins to an extent.
May 1, 2014 at 12:51 am
[…] showing the pneumatic internal structure. Compare to similar views of dorsals in this post and this one. This is actually one half of a matched set that includes both halves of the centrum. I left with […]
March 13, 2021 at 11:10 pm
[…] and about most of the CT and other cross-sections that I’ve published or used over the years (example), is that they’re more or less bilaterally […]