Several years ago, I
was fortunate to be asked to helm the scientific description of Jane, a very
complete skull and skeleton of a subadult tyrannosaurid found in the Hell Creek
Formation of Montana by the Burpee Natural History Museum (Rockford, IL). That
project is presently winding down, where I have only the ribs, gastralia, and
hemal arches to write up, in addition to other loose threads.
Following the model of
H. R. Giger’s posthumously published Alien Diaries, I will document the closing
stages of the Jane monograph in the style of a summative journal on the days I
push that work forward. State abbreviations (e.g, AK, NY, WY) are used instead
of people’s names to preserve their anonymity. Since this diary pertains to a
research project that is in progress, new data and anatomical description are
excluded from the narrative. It is my hope that some of you will take an
interest in reading about how such a project is undertaken, and that this inside
account will satisfy your curiosity.
 |
| Today’s view of the Jane monograph upon wrapping up for the day: a pair of cervical ribs that will be in a holding pattern for a week. |
Tuesday September 30, 2014
A two-hour drive from Kenosha to the Burpee Museum; arrived
shortly after 10 am. Once in collections, I first measured the height of the
spinous process of each cervical vertebra from the dorsum of the laminae so
that I can compare this specimen with the ratio of character 212 in Brusatte et
al. (2010). I only measured the height from the ceiling of the vertebral canal
during a previous visit; I take up to 41 measurements for each vertebra, but
that doesn’t always capture everything. WI and I went to the gallery to remove
the cervical ribs from the mounted skeleton; I photographed the ribs in
position before WI removed them; I left with one in hand while WI removed the
rest.
Back in collections I worked on describing the new rib – I
wrote up three last Tuesday – until WI brought down the rest; I then put the nine
ribs in their correct sequence. All of the cervical ribs were found associated
with the skeleton, but detached from the vertebrae, so I do not know which
vertebrae they belong to. However, working out the correct sequence was
straightforward. Several ribs are still upstairs because they are fixed to the
mount, so I will have to write those up while standing in the display!
IL stopped by briefly and I raised the possibility that our
respective institutions might get some publicity out of this formative stage of
the monograph, instead of waiting for its publication to take action. We
discussed the possibility of a documentary to follow up on the one about the
discovery and collection of the skeleton – Jane the Mystery Dinosaur - that was
done in 2006. It is just an idea at this stage and a tangible plan is required for
it to get anywhere.
After that, I labeled each rib with post it notes, marked with
their relative sequence; there is only one set of duplicates (i.e., a matching
left and right bone of the same anteroposterior sequence). I found that the
posteriormost cervical rib on the right side was on the mount inside out and
upside down; it will be an easy fix for WI when it goes back on display. After establishing
the sequence I finished writing up the anteriormost rib in time for lunch.
Following lunch, a meeting with OH and IL regarding next
summer’s field season ate up of much of the afternoon, but it was worth the
investment of time for solving many of our field logistics this far in advance.
I was left with a relatively short amount of time to start on the description
of the paired ribs before I had to leave, but I managed to give the general
description, the primary dimensions, the lateral surface of the expanded
anterior region, and a good start on the tuberculum.
This skeleton sometimes seems endless, even this close to
the end, but there’s always aspects of its morphology – even in cervical ribs –
that are new and exciting that give me the incentivizing thrill to keep going
forward. I get to see the transformation of serially homologous features from
one rib to the next; this opportunity gives me a better understanding of the
nature of some features, such as the various forms taken by the cranial process
along the cervical series. After I notice such things, the following week seems
to be a long, long way off and snapping off the twig of the day’s task takes
great strength.
Oh yes – as of today, the manuscript is 350 pages long and
there are 173 pages of tables of measurements.
References cited
Brusatte, S. L., M. A. Norell, T. D. Carr, G. M. Erickson,
J. R. Hutchinson, A. M. Balanoff, G. B. Bever, J. N. Choiniere, P. J.
Makovocky, & X. Xu. 2010. Tyrannosaur paleobiology: new research on ancient
exemplar organisms. Science 329:1481.
Giger, H. R. 2014. The Alien Diaries. Section 9
Entertainment: 660 pp.
"I take up to 41 measurements for each vertebra, but that doesn’t always capture everything."
ReplyDeleteAlmost anything's better than Brochu's (2003) Sue monograph when it comes to measurements. The one measurement he provides for postaxial presacrals? Dorsoventral height. :| Why would that ever be chosen over central length? The caudals don't even get measured.
"Several ribs are still upstairs because they are fixed to the mount, so I will have to write those up while standing in the display!"
It's not like they have world experts on tyrannosaurs writing up a monograph of the material or anything. I mean, it'd take work to take them off the mount.... :| Maybe museum resources are in a far worse state than I imagine, but you'd think the one time the curators would disassemble mounts would be when their specimen is being initially described or redescribed. There's no better time.
Hi Mickey – I’m sure plenty of holes will be found when this work is published that are presently invisible to me.
ReplyDeleteWith regard to the ribs, the issue is with the mount itself – even though it is constructed as a rack, where bones can be removed separately, in only a few areas this has proven impossible. It certainly hasn’t been without the earnest effort of museum staff to free them; the mount is simply too difficult in some areas to remove bones because they are either fixed in place or removal would damage them. In fact, this is the first time that the skeleton has been so extensively disassembled for research, so we are all on the learning curve regarding the armature.
Regardless, the access I’ve had to Jane (and other fossils) at the Burpee Museum, and the courtesy with which I’ve been treated there, ranks with the best museum collections I’ve had the privilege of visiting, including the AMNH, CMN, FMNH, MOR, NMMNH, ROM, RSM, SDSM, and others. I can assure you that the Burpee Museum staff take this project very seriously and are making great accommodations to see that it happens.