The elephant in the living room: Amphicoelias brontodiplodocus
October 7, 2010
Well, this is frustrating. Over on the VRTPALEO mailing list, all the talk at the moment is of the new paper by Henry Galiano and Raimund Albersdörfer (2010), describing their rather comically named new species Amphicoelias brontodiplodocus. And to be fair, the material they’re describing is sensational, and the photographs in the paper are pretty good.
But I don’t want to talk about that.
There are other things I do want to talk about, but I can’t help feeling that whatever else we cover here at the moment, everyone is going to be thinking “Yes, but what about Amphicoelias brontodiplodocus?” So I don’t think I can go on to write about the things I want to before we’ve at least acknowledged the existence of this paper.
And yet, and yet … I have so many problems with this paper, even before we get to the controversial part, namely the conclusion that Diplodocus, Barosaurus, Apatosaurus, Supersaurus, Suuwassea, Tornieria and Eobrontosaurus are all congeneric with Amphicoelias — more precisely, conspecific with the single species Amphicoelias altus.
Aside from the a priori unlikelihood of that, we have these problems:
- First, and maybe most important, the specimens described in this paper are all privately owned, so whatever conclusions might be gleaned from examining them are not replicable by other scientists. For the Society of Vertebrate Paleontology, that’s a deal-breaker right there (and I am in full agreement).
- Second, the new paper doesn’t seem to be published: at least, no-one’s yet claimed that it exists in numerous identical hardcopies, so for ICZN purposes the new name is a nomen nudum. (That will surely change, though: I am confident that Dinosauria International, LLC are perfectly capable of printing off a hundred copies and sending them out to libraries.)
- Third, the paper doesn’t seem to have been peer-reviewed: at least, there’s nothing in the acknowledgements that indicates that it was. It doesn’t seem to have been edited in anything like the usual sense either.
- Fourth, there is mechanical evidence of enormous sloppiness in the composition of the paper. For example, many cited papers are not included in the REFERENCES CITED section, and most of the references that are included are not in fact cited in the paper. As an example, my own Taylor et al. (2009) is cited but not referenced, while Taylor and Naish (2005) is referenced but not cited. Lots of Upchurch papers in the bibliography are never cited. That doesn’t give me confidence about the rest of the work.
- Likewise, the paper is rife with typos and grammar errors, such as this from page 28: “A. louisae is by far the most widely acclaimed example, and B. excelsus skeleton mounted and exhibited in the Peabody museum. Despite the familiarity of these Apatosaurus specimens various aspects of it [sic] skeleton remain poorly known.” Not a killer, but again it doesn’t give me confidence.
- “brontodiplodocus” is a stupid name.
Against that backdrop, consider the radical taxonomic hypothesis. All Morrison formation diplodocids (and some from elsewhere) are considered to belong to a single species, Amphicoelias altus … except for the new specimens, which belong to the new and separate species A. brontodiplodocus. In other words, we’re being asked to believe that the new specimens are more different from all other Morrison diplodocids than any of them are from each other. And yet we’re brought to this conclusion by the very animals that are apparently not as similar. It’s as though I discovered dogs, and thereby concluded that lions, cheetahs and house-cats are are all the same species.
So this is not just a matter of extreme taxonomic lumping: it’s weirder than that. It’s “all the other stuff is just a single species except the one we’ve discovered which is different”.
As Tom Holtz is fond of saying, extraordinary claims demand extraordinary evidence. I’m not going to come out and say it’s impossible that all Morrison diplodocids except the new specimens were conspecific. But if I were the one setting out to propose such a heterodox hypothesis, I would do myself every possible favour: I’d do it from properly accessioned specimens in public museums, I’d publish in a recognised peer-reviewed journal, I’d take care to get my nomenclature right, match up my citations and references, and generally dot the i’s and cross the t’s.
Until that’s done with this new material, I’m not sure there’s much point in investing a lot more effort in evaluating the phylogenetic/taxonomic claims.
(Henry, I know you’re an occasional reader here. Sorry to be so negative, but I’m sure you’ll understand that I have to call ‘em as I see ‘em.)
- Galiano Henry, and Raimund Albersdörfer. 2010. A new basal diplodocid species, Amphicoelias brontodiplodocus from the Morrison Formation, Big Horn Basin, Wyoming, with taxonomic reevaluation of Diplodocus, Apatosaurus and other genera. Dinosauria International, LLC, Wyoming. 50 pages.
- Taylor, Michael P. and Darren Naish. 2005. The phylogenetic taxonomy of Diplodocoidea (Dinosauria: Sauropoda). PaleoBios 25(2): 1-7.
- Taylor, Michael P., Mathew J. Wedel and Darren Naish. 2009. Head and neck posture in sauropod dinosaurs inferred from extant animals. Acta Palaeontologica Polonica 54(2): 213-220.