How Much of an Upset Do You Want It to Be?


Really? We get to see that Greg Paul was really really right about that whole “neoflightless” thing? In case you hadn’t heard — and if you’re reading this blog, you most likely have — Archaeopteryx lithographica, famed urvogel, has been dethroned as, well, the urvogel.

Skeleton of STM 27-2, holotype of Xiaotingia zhengi Xu et al., 2011. Grey areas are reconstructed from severely-damaged bone in the braincase region. Lengths of the tibia and metatarsus are reconstructed, as are the conjoining ends, which are not preserved.

Xu Xing and several of his students and colleagues have named a new taxon, Xiaotingia zhengi, from a specimen (mainslab, missing the counterslab) that was recovered from northeastern China and from sediments in the late Mesozoic. They may or may not predate the arrival of Archaeopteryx lithographica. Moreover, a phylogenetic analysis of over 300 characters and nearly 90 taxa, an adaptation of the Theropod Working Group analysis supports the placement of Archaeopteryx lithographica outside of the stem leading to birds where it splits from the Dromaeosauridae and Troodontidae (Deinonychosauria). This position, effectively at the base of a clade including it and Deinonychosauria, has been linked to Greg Paul’s theory that “Archie” is, in fact, a tiny flighted dromaeosaur that gave rise to bigger-bodied, flightless (hence “neo”-flightless).

Now, personally, I’m interested in something else about this specimen, which I will get to in a while, perhaps a hint of which is in this blog’s general theme. I wanted to take this post to discuss something that came up tangentially.

STM 27-2, holotype of Xiaotingia zhengi Xu et al., 2011.

Denver Fowler has commented here in regards to Raptorex kriegsteini, and it was further mentioned not that long ago here by both Denver and Mike Taylor on the Dinosaur Mailing List, both because of LH PV18 (type of the aforementioned specimen) and others. A while back, I mentioned the case of two pterosaur specimens, KJ1 and KJ2, which may have a large effect on the biomechanics of cranial crests and the taxonomy of the “nyctosaurids,” pterosaurs similar to Pteranodon longiceps and kin. The provenance of STM 27-2, holotype of Xiaotingia zhengi Xu et al. (2011) is another example. From the SOM of the latter paper:

The holotype and only known specimen of Xiaotingia zhengi was acquired by the Shandong Tianyu Museum of Nature from a fossil dealer, according to whom the specimen was collected in the Linglongta area, Jianchang, western Liaoning, China. However, he could not provide accurate information as to the quarry in which the specimen was collected. […] Although the slab preserving the Xiaotingia zhengi holotype is most similar to the fossil-bearing beds of the Tiaojishan Formation, it is difficult to distinguish between Tiaojishan and Yixian shale slabs on the basis of macro-sedimentary features. Discoveries of additional specimens with definite locality information, or micro-sedimentary analysis of the slab preserving the Xiaotingia zhengi holotype, will help to resolve this issue.

Fowler et al. (2011) especially raised issues with Sereno et al. (2009) on the provenance of LH PV18 due to the lack of certainty and the apparent contradictory statements of fossil dealers. If such an issue were to matter, the above specimen would be among them. The authors are careful, however, as they make little in the biostratigraphal context (unlike Sereno et al.) which allows the specimen to essentially speak for itself. Here, we are once again faced with the question of the value of material which we cannot reliably date, and whether that date actually matters.

My personal feeling is that the specimen is of value regardless of its provenance. In a way, this means that material acquired from the Tuscon Rock and Gem Show, itself often in controversy over such specimens, can also be of such value. It has much to do with specimens like this one, which AMNH preparator Jason Brougham brought up on his blog here, for different reasons:

A “conchoraptorine” currently in private hands.

or these ones:

Specimens of the “mitrata” oviraptorid … or oviraptorids. It’s actually not quite that clear. The first is found from Ask.com on Oviraptor (of philoceratops fame, which is most certainly isn’t) while the other comes from Witmer Labs site.

These specimens are valuable, effectively lost to Science, they tell us nothing. But as casts, as surficial data, they can be used for other things, such as datapoints in broader analyses, morphological variation data, etc. They cannot be cut up, scanned under computed tomography or magnetic resonance imagine, or sampled for microtextural analyses, but their gross anatomy can be assessed (to the degree that the cast and thus unprepared “matrix” allows). Should we have the opportunity, this material qualifies other work, and is thus of importance, although not to the degree that having the actual specimen in an institution (and the mantra “It belongs in a museum!” so applies in this case). It cannot replace the original, not by a long shot, but casts are valuable for researchers even when the original is available, because that material may be too large to handle, too rare or valuable to cut up or into, or too fragile to touch, expose, etc., as in the famous Iguanodon bernissartensis skeletons extracted from the Bernissart coal mines in Belgium, which “suffer” progressive pyritization.

But this is only the tip of the ‘berg, as it were: Here, I discuss real, stable, preserved specimens which have been lost through the human agency of desiring to keep private and hidden what are ostensibly “cool” toys, but are valuable pieces of information to scientists. But there’s another type of “lost” specimen, and that’s the destroyed specimen. I will get to that in a bit.

Fowler, D. W., Woodward, H.N., Freedman, E.A., Larson, P. L. & Horner, J. R. 2011. Reanalysis of “Raptorex kriegsteini“: A juvenile tyrannosaurid dinosaur from Mongolia. PLoS ONE 6(6):e21376.
Sereno, P. C., Tan L., Brusatte, S. L., Kriegstein, H. J., Zhao X.-j. & Cloward, K. 2009. Tyrannosaurid skeletal design first evolved at small body size. Science 326:418-422.
Xu X., You H.-l., Du K. & Han F.-l. 2011. An Archaeopteryx-like theropod from China and the origin of Avialae. Nature 475:465-470.

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15 Responses to How Much of an Upset Do You Want It to Be?

  1. I agree completely that specimens are of value even if they’re of uncertain provenence or only casts of privately held specimens. Sure you can’t do everything with a cast, but there are plenty of natural casts and molds (Scleromochlus, Kakuru, etc.) and we don’t throw those out. Ditto for specimens which naturally have uncertain provenence due to reworking or eroding out and being displaced. There should be no difference between natural and artificial loss of data besides the latter being more regrettable due to the possibility of avoiding it. The bottom line is specimens don’t have to be useful for everything to be useful for something.

  2. DF says:

    Specimens without locality data are morphologies without context. They might seem to be a good record of morphology, but they can be extremely difficult, if not impossible, to properly compare with specimens for which strat data is known. Making them holotypes is just kicking the problem down the line.

    Perhaps a good compromise would be to allow study of casts / specimens without data, but not allow them to be holotypes. That way at least, we should avoid any future “is it or isn’t it” taxonomy seniority issues, when dealing with new specimens that do have data.

  3. I agree in general about not allowing casts or specimens without locality data to be holotypes, but there are certain degrees of certainty that can be derived from specimens even when they lack locality data, including unique sedimentology. This latter aspect was used to resolve (mostly) the locality of the holotype of Hallopus victor. Similarly, much of the type material for various taxa such as Triceratops horridus and Manospondylus gigas were/are unresolved, but we are fairly certain not only from which portion of the US they derive, but from the county and state they come from.

  4. DF says:

    Triceratops horridus is a problem, unfortunately. We need metre-scale strat position, not just the general area. I don’t have any personal experience dealing with Manospondylus.

    I agree that if you can relocate a quarry, or place a specimen due to some unique sedimentological data (perhaps using REE signatures; e.g. Trueman’s work) then it’s fine. I would be curious as to how many purchased specimens come with quarry photos that allow accurate relocation.

  5. Nick Gardner says:

    I have to second Denver’s sentiments here, but I’d state all of the above is moot until the original material is in the hands of someone who can properly study, regardless of whether they are interested in it for morphological data or relocating its quarry of origin. While it remains in private hands, this is pretty much shooting in the breeze.

  6. I don’t see what the problem is for holotypes without locality data. Everyone says provenence shouldn’t be used as a diagnostic character, so the anatomy should speak for itself when comparing to other taxa with known localities. Locality data can suggest possible synonymies and reject other synonymies, but it isn’t diagnostic in itself when we don’t know all the taxa which existed.

    • Ideally, a holotype should have provenance and associational information provided for it immediately. This ideal is the mark you shoot for when you name new taxa. I’m not a zoologist, who may often describe cryptid species from skins and such which are provided by other collectors or hunters, and thus may often lack provenance data. Chris Taylor remarks here about provenance being “Brazil,” which is ridiculous in comparison to what is provided NOW with GPS coordinates and such. There is no reason we should settle for less than the ideal, regardless of the quality or value of the specimen. In this, I think Denver and I agree. This makes private collector-based material more problematic when procured solely to sell to those who are unlikely to care about the scientific value of the specimens. Sedimentology, preparation techniques, associated material, these things matter not in such a context. That is, unsurprisingly, why the Liaoning beds are so well-sampled nowadays, as they are being professionally hunted by museums to combat private collector-based hunting; the holotype of Sinosauropteryx prima, as well as Beipiaosaurus inexpectatus, arrived in such a fashion as that of Xiaotingia zhengi, and this impairs us knowing from where in this formations they may derive, and thus their relative stratigraphic relationship.

      • “There is no reason we should settle for less than the ideal, regardless of the quality or value of the specimen. In this, I think Denver and I agree.” Well that’s the crux of our disagreement then. I’m a realist who will settle for less when there’s no guarantee another specimen will be found. It would be ideal to only use complete specimens for holotypes, but maybe another Pedopenna will never be found, for instance. So might as well name it now with incomplete information instead of waiting a decade, a century or forever for a specimen with a skull, or stratigraphic information, to show up.

        • This path leads inevitably, in it’s slippery way, down the road where everything proliferates with names.

          I am patient, and can wait decades for something to expand my knowledge on a thing. I don’t need a false label to content myself with encapsulating what I know now under the pretense that we might as well do this, and figure out what to do with it later … when later happens. Cope, Marsh, and others tried it the other way, and that hasn’t necessarily worked out well for them. A good number of holotypes have been replaced in this manner, under our assumption that the better specimen is the better holotype. This was even the option when Allosaurus fragilis was named, prompting the current effort to shift the types. If we can find ourselves more willing to take the time, effort and patience to investigate substantively beforehand, then we may never have to settle for the inadequate type specimen. This would render a large list of taxa (with tooth-based forms at the top) poor, and I suspect that is the best point at which we should proceed.

  7. Pingback: Raptorex is Doomed | The Bite Stuff

  8. Schenck says:

    Two things:

    (1) Anchiornis displaced Archaeopteryx as the basal bird in Xu et al’s analysis, but Lee & Worthy, in a likelihood analysis, reinstated Archaeopteryx as such.

    (2) Taxonomic names are issues of convenience for the discussion of the status and relationships of organisms, and names requires holotypes. Things like Raptorex or Triceratops horridus are worth formal discussion in the science, thus are worthy of names, and thus holotypes don’t really need GPS coordinates or stratigraphic descriptions; obviously this sort of information should be included when available. And obviously if you’re making an ontogenetic and stratigraphic arguement for a revision of Triceratops/Torosaurus, holotypes that don’t have stratigraphic data associated with them can’t figure into that argument, which is unfortunate.

    Ok I lied three things:

    (3) You mention fossils held in private personal collections and fossils destroyed as ways of loosing fossils, but what about improper academic collections? How often is potentially useful material collected, brought back to a university/college/etc, and never properly studied or published on? I’m not talking about material that proper researchers at least /intend/ to publish on, but rather, practically-private university/departmental collections, or material collected by American universities in foreign countries that is improperly taken out of those countries. This isn’t a major source of lost fossils, but there is some loss associated with this.
    For my own part, I’m happy to be involved with a group that returns material to the country it was collected from. For example, (and this was settled before I started working with the group), this group collected a large volume of material in a foreign country in cooperation with a local museum and government, and then prepared and preserved the material, published on it, and just this year returned it. The local museum didn’t have the facilities or the number of personnel to do this, but now they have a suitcase full of specimens (these are mouse sized animals) individually prepared packaged and label, held in display cases, etc. This of course is the way things are supposed to work, but that’s not always the case. That’s an affront to the country the material was collected from, and when it’s not published on, it’s an affront to the science at large too!

    • Note that this post was written before the revised analysis. It should be clear that I didn’t take the current position for granted, and am familiar with the vagaries of phylogenetic analyses revising one another.

      Holotypes that lack locality info are one thing: this makes it difficult to associate them into fine-level stratigraphic work, but not impossible. It is still possible to determine that a specimen derives from a given formation (at the least). The issue of whether to toss out specimens without locality information becomes problematic when you realize that virtually ALL specimens from 1860s onwards including the “big” Hell Creek finds are effectively useless. We might as well not use names like Tyrannosaurus rex, Triceratops horridus, Ankylosaurus magniventris while we’re going at it. Problematically, ontogenetic arguments have been conducted from specimens from different localities, and slightly different horizons. Even the Scannella/Horner and Goodwin/Horner ontogenetic series require specimens at different stratigraphic levels, possibly only separated by a couple hundred thousand years, but separated in time they likely are, nonetheless. You’d need extraordinary bonebed preservation, which is rare indeed, to make a definitive argument, and even then you’re likely to miss using a holotype for context.

      I’d say improper handling of fossils is an effective destruction method, right? One can destroy something through perversity or through ignorance and neglect.

  9. Schenck says:

    Didn’t realize the date on this posting! It just showed up in my newsfeed recently, maybe you bumped it because of the other postings on raptorex? Anyway, interesting points in your comment.

  10. Adam Ludford says:

    Hi Jamie,
    We would like to use the image of Xiaotingia zhengi for academic purposes on our website, http://www.explorebioedge.com. Do you have any contact details where we could ask permission?
    Kind Regards,
    Adam

    • All skeletal illustrations produced by me on this website are CC-BY, so you are free to use so long as you attribute the source of the illustration to me. You could cut it in half, color it purple and put pink polka dot underwear on it, for all I care :)

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