STL Science Center

STL Science Center

13 December 2011

Is There Any News?

Supersaurus is as big in the recent (past 30 years) history of paleontology as it was in its era of plant eating domination. A gut as large as the one on Supersaurus certainly led to many eating competition prizes and now, all that fuel which created such an enormous dinosaur has led to a great deal of excitement in us far smaller creatures about what this giant was like and what we know about them. The bones are enormous, of course, and any paper that has made use of the bones has been forced to show them on whole pages and, where details of small segments of these enormous bones are required, without going anywhere near showing the entire bone on that whole page dedicated to the bone.

I think, despite the many papers and articles I found today that go into very good, fair, sometimes crappy, and even extraordinary detail about Supersaurus, I am going to stick with those papers that are always of the utmost importance to dinosaurs, effectively what we could consider their birth certificate into human culture: discovery, description, and naming articles and articles that step back years and years later and discuss the morphology of the species. To that end, the first paper that I will present is James Jensen's October 1985 article which ties Supersaurus vivianae and Ultrasaurus mcintoshi into a conspecific hierarchy, effectively eliminating U. mcintoshi from the vernacular, and making it a junior synonym, in favor of Supersaurus. Though this would actually happen later, after the name was changed to Ultrasauros, the groundwork for the name change was set by Jensen himself unintentionally. I am sure Jensen doesn't mind considering the third dinosaur he described in this 1985 article, Dystylosaurus edwini is now also considered to be a specimen of Supersaurus misnamed. Another interesting item from the article that has been revisited over the years is that Jensen repeatedly refers to Supersaurus as a Brachiosaur and Supersaurus is now known to exist within the diplodocid family. A minor detail that has been changed, but a very important detail as it is very important to the family tree of sauropods.

The second article, by David Lovelace, Scott Hartman (who does fantastic skeletal recreation that I have used to teach myself quite a bit), and William Wahl, discusses the morphology of Supersaurus and evaluates diplodocid phylogeny twenty two years after Jensen's article. Lovelace, Hartman and Wahl's 2007 article describes a new specimen of Supersaurus recently found and goes on, after describing it, to discuss osteology and shows an alternative placement for Supersaurus as an apatosaurid specifically, a subfamily of diplodocids generally not attributed to the Supersaurus genus. In fact, most places I have looked, and there may be a debate I do not know about concerning this placement, has Supersaurus in the diplodocid family in the subgroup diplodocinae where this paper makes the genus a part of the diplodocid family and the apatosaurine subgroup. I think I may have to shoot an email to Mr. Hartman seeking his opinion of their placement in that subgroup to more fully explain it to all of us. The article goes in to great detail on Supersaurus and sadly I do not have the time it would take to discuss it all, but there are some wonderful photos of bones and well done skeletals, as would be expected, used in the article. Take a good chunk of the day to at least skim the article, 18 pages is a lot of science reading after all, and I know you will learn a lot about the dinosaur and its family at the same time.

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