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A Dissection of Dakotaraptor Status


Troodon

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 Dakotaraptor steini was found in a multi-species bonebed in the Hell Creek Formation and lots of questions have been raised around this material since it was described.  Elements of the holotype were found to belong to a turtle (furcula) and Anzu (Tibia) and questions raised on others.  To make matters worst the holotype is not available for study..  So its been shrouded in controversy.

 

A good review of where we currently stand is presented in the attached Twitter thread

 

 

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Nice "posts".  I liked the info, but twitter is a terrible medium for that type of posting or discussion.  I did like this quote the best "Unfortunately, the mess of Dakotaraptor, and it's admittedly overblown controversy, is due to the actions of those directly, indirectly, and not at all involved in the process of its description...."

 

Yes, even the people totally uninvolved in the creature are to blame! LOL  It sounds funny even though its true.

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"There is no shortage of fossils. There is only a shortage of paleontologists to study them." - Larry Martin

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I think keeping the Holotype from others is significant and feeds the controversy.

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Definitely not the cleanest and most issue-free way of describing a new species. The lack of access to the holotype runs contrary to the accepted norms of paleontology. Most folks lack the detailed knowledge to assess information in the paper describing this species (myself included). We are left to trust the community who does understand its contents and its implications and then we form a meta-opinion based on how it was received by those in the know.

 

To me, (one of the people totally uninvolved ;)) this paper hovers unnervingly close to Pons-Fleischmann territory. While it is true that there is more to this story than there ever was to "cold fusion" (as there are actual dinosaur bones involved) it is unclear whether Dakotaraptor will join a long line of pathological science like 'memory of water' or 'N-rays'.

 

The ghost of Dakotaraptor still haunts DePalma as it taints subsequent extraordinary claims like the Tanis fossil site. I have read through the paper on the initial findings for that site and found it curious. There seems to be some evidence for this site being a window into the K-Pg extinction but it is well above my pay grade to critique the validity. Had it been written by anybody else but DePalma it would not be subject to "the boy who cried wolf" criticism.

 

https://en.wikipedia.org/wiki/Tanis_(fossil_site)

 

It would be a nice resolution for the Dakotaraptor holotype to be made available but I'm not holding my breath.

 

 

Cheers.

 

-Ken

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5 hours ago, Troodon said:

 Dakotaraptor steini was found in a multi-species bonebed in the Hell Creek Formation and lots of questions have been raised around this material since it was described.  Elements of the holotype were found to belong to a turtle (furcula) and Anzu (Tibia) and questions raised on others.  To make matters worst the holotype is not available for study..  So its been shrouded in controversy.

 

A good review of where we currently stand is presented in the attached Twitter thread

 

 

I'm not a vertebrate person so excuse my ignorance, but why is the holotype not available for study? I would think that simple fact would render this species nomen dubium...

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4 minutes ago, Crusty_Crab said:

I'm not a vertebrate person so excuse my ignorance, but why is the holotype not available for study? I would think that simple fact would render this species nomen dubium...

 

You need to ask DePalma.  

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Yeah that is the underlying issue. DePalma has in a lot of ways approached this in a very...uh...sensationalist manner. It's not like, say, Nick Longrich or Dave Evans haven't also erected Late Cretaceous theropod taxa on fragmentary remains, but the issue with DePalma's work is that:

 

1. access to the majority of material is restricted because he has the material in his private collection

 

2. the material that is available for comparative study is not dromeosaurid

 

3. he's put a LOT of effort into the press material and curation of his associated image in the press, and much less into the comparative work that forms the basis of his interpretation that this material is all dromeosaurid

 

 

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I remember hearing about the press release going out before the paper, but Some of the aspects have me confused (although that doesnt take much).  My understanding of the process is that the paper has to be published and peer-reviewed before a new name can become valid.  Part of that peer review is examination of the holotype which also requires that it is housed in a public institution.  So has the paper been reviewed?  Was the specimen ever in public access? Without all that, isnt name automatically nomen dubium?

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"There is no shortage of fossils. There is only a shortage of paleontologists to study them." - Larry Martin

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17 minutes ago, hadrosauridae said:

I remember hearing about the press release going out before the paper, but Some of the aspects have me confused (although that doesnt take much).  My understanding of the process is that the paper has to be published and peer-reviewed before a new name can become valid.  Part of that peer review is examination of the holotype which also requires that it is housed in a public institution.  So has the paper been reviewed?  Was the specimen ever in public access? Without all that, isnt name automatically nomen dubium?

I would say neither the peer reviewer nor the author can determine the validity of a name. That's left to the larger scientific community. For invertebrates, the community is small, everyone knows each other and the atmosphere is collegial so thats usually not a problem. I get it that with dinosaurs, thats not the case, with lots of big money and names on the line. In my opinion, that someone would even consider keeping holotypes in their personal collections and not in a public institution is antithetical to science. In science, reputation is everything. You might be right, but if your reputation is rubbish, we'll never know the difference. I'm seeing DePalma's reputation is not high, and therefore all of his work is suspect. 

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39 minutes ago, hadrosauridae said:

I remember hearing about the press release going out before the paper, but Some of the aspects have me confused (although that doesnt take much).  My understanding of the process is that the paper has to be published and peer-reviewed before a new name can become valid.  Part of that peer review is examination of the holotype which also requires that it is housed in a public institution.  So has the paper been reviewed?  Was the specimen ever in public access? Without all that, isnt name automatically nomen dubium?

 

The formality of associating a name with a specimen is really quite flexible; there is no requirement of peer review and "published" represents a wide range of possible activities. Press releases do not invalidate the name, but in this case it is more a symptom of an issue with how RdP does his science; it is very much focused on press coverage and not rigor. 

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20 minutes ago, Crusty_Crab said:

I would say neither the peer reviewer nor the author can determine the validity of a name. That's left to the larger scientific community. For invertebrates, the community is small, everyone knows each other and the atmosphere is collegial so thats usually not a problem. I get it that with dinosaurs, thats not the case, with lots of big money and names on the line. In my opinion, that someone would even consider keeping holotypes in their personal collections and not in a public institution is antithetical to science. In science, reputation is everything. You might be right, but if your reputation is rubbish, we'll never know the difference. I'm seeing DePalma's reputation is not high, and therefore all of his work is suspect. 

 

I'm not entirely clear on what the public/private status of the PBMNH...it's apparently a non-profit 501(c)3 but I'm not sure if it qualifies as a public repository or not i.e. are the collections protected as a permanent scientific repository or are they technically property of RdP or a 501c3 that he controls. There are a range of semi-public museums in Europe that seemingly follow this model and a lot of scientists, especially German scientists, have no problem publishing on those fossils, but this is generally not done in the US research ecosystem. I'm not going to pass judgment on whether one system is "better" than the other, but I will point out that the underlying problem is that people who have wanted to reexamine this material have not been able to, and it is therefore somewhat surprising that, despite a ton of work being done on Hell Creek fossils for over a century, somehow RdP has found a ton of Dakotaraptor whereas no one else has. So, people find that fishy.

 

Personally I have no opinion on the science itself because I don't do dinosaurs and I don't really care much about reputation per se, but it's worth recognizing that there is some irregularity in how work was done on Dakotaraptor and how the PBMNH has facilitated (or rather, not facilitated) the public access typically associated with normal scientific reproducibility.

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8 minutes ago, jdp said:

 

The formality of associating a name with a specimen is really quite flexible; there is no requirement of peer review and "published" represents a wide range of possible activities. 

Only too true unfortunately.  Self-published works are fine, as long as you print up a few extra copies and send them to a few libraries and museums so other researchers have "access" (however limited) to the publication.  It seems rather curious to me, though, that names published in theses and dissertations are not considered to be valid.

 

It seems to me that a possible solution would be to restrict the name Dakotaraptor steini to the holotype, as it is not available, and erect a new name based on good and properly curated material.  This is not uncommonly done with invertebrate fossils when the type material is lost and the original description is so vague no-one can be sure what the diagnostic characters ever were, as sometimes happens with species described long ago.

 

Don

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17 minutes ago, FossilDAWG said:

It seems to me that a possible solution would be to restrict the name Dakotaraptor steini to the holotype, as it is not available, and erect a new name based on good and properly curated material. 

 

The problem is that, as far as I understand it, there is no known Dakotaraptor material that is not part of RdP's institutional collections, and that doesn't really help rule out the possibility that some of the material RdP attributed to Dakotaraptor might belong to other theropods, such as Anzu.

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20 minutes ago, jdp said:

 

The problem is that, as far as I understand it, there is no known Dakotaraptor material that is not part of RdP's institutional collections, and that doesn't really help rule out the possibility that some of the material RdP attributed to Dakotaraptor might belong to other theropods, such as Anzu.

 

I've seen a couple of foot claws in private collections that are consistent with the holotype but nothing in museums.  Of course a few teeth are out there that seem to match the holotypes description 

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Yeah sorry, I wasn't quite specific. There is no material accessioned into museums and therefore available for scientific study which is identifiable as Dakotaraptor and therefore no way for researchers who are not RdP to really meaningfully assess the validity of his description. I have no reason to doubt that there are not interesting and perhaps relevant specimens in private collections, but until they are in a public repository it is difficult for the research community to weigh in on it and, more importantly, to use those as data in analyses of paleoecology, phylogeny, etc. This is in many ways a similar problem to the Nanotyrannus debate; there may very well be specimens in private collections that are relevant to this discussion but unless it is part of a public repository it's not really available for study and the scientific community needs to make do with what they have available to them.

 

This is in many ways a conversation about the specifics of the standards of the field and less a discussion about the specifics of which dinosaurs actually lived in the HCF. A similar thing applies to a lot of other material in private collections; there are a lot of fossils which are known about colloquially but which we can't really say anything about because nothing we say is inherently verifiable if other researchers want to revisit those fossils.

Edited by jdp
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3 hours ago, FossilDAWG said:

It seems to me that a possible solution would be to restrict the name Dakotaraptor steini to the holotype, as it is not available, and erect a new name based on good and properly curated material.  This is not uncommonly done with invertebrate fossils when the type material is lost and the original description is so vague no-one can be sure what the diagnostic characters ever were, as sometimes happens with species described long ago

 

Don, in your example, wouldn't the "name" of the improperly curated specimen be just 'interesting reading' if another name was erected based on properly curated discoveries of the same kind of animal?  Would the subsequent authors even need to acknowledge the "interesting reading"?

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The human mind has the ability to believe anything is true.  -  JJ

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25 minutes ago, JohnJ said:

 

Don, in your example, wouldn't the "name" of the improperly curated specimen be just 'interesting reading' if another name was erected based on properly curated discoveries of the same kind of animal?  Would the subsequent authors even need to acknowledge the "interesting reading"?

Correct me if I'm wrong, but that is the implication of nomen dubium. The description is assigned to the name, which is unverifiable and therefore nomen dubium. That leaves it free for someone else to find something, describe it to current standards and is verifiable, and assign another name to it. 

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56 minutes ago, Crusty_Crab said:

Correct me if I'm wrong, but that is the implication of nomen dubium. The description is assigned to the name, which is unverifiable and therefore nomen dubium. That leaves it free for someone else to find something, describe it to current standards and is verifiable, and assign another name to it. 

 

That is what I wondered, too.  But, I'm not sure those circumstances are specifically covered by the "nomen dubium" designation.

 

From the ICZN FAQs:

Quote

Available names which cannot be interpreted and are not used, e.g. if the type is missing, can be a problem for taxonomists. Such a name is often referred to as a nomen dubium (plural nomina dubia) or dubious name.

Such names do not become unavailable, even if they are not used as valid, they may become valid again in the future as they can continue to compete in homonymy and, if later applied to taxa, can compete in synonymy. This may be a problem for the stability of names e.g. as potential senior synonyms or homonyms may overturn the established usage of junior names.

The Code can allow prevailing usage to be kept where this will aid stability, even where this goes against the principle of priority. E.g. a forgotten name not used as valid since 1899, and found to be a senior synonym or homonym, can be declared a “nomen oblitum” and an established junior name for the same species a “nomen protectum”. This makes the junior name valid and the senior name invalid (Articles 23.2, 23.9.2). Difficult cases can be referred to the Commission for a ruling.

Last updated: 2010-04-29 14:53

 

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The human mind has the ability to believe anything is true.  -  JJ

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2 hours ago, JohnJ said:

 

Don, in your example, wouldn't the "name" of the improperly curated specimen be just 'interesting reading' if another name was erected based on properly curated discoveries of the same kind of animal?  Would the subsequent authors even need to acknowledge the "interesting reading"?

Where I have seen the approach used is cases where it is impossible (and very likely to remain so) to know what the species actually is.  For example, imagine a situation where the type specimen is lost and the description is so poor it could apply to several distinct species or even genera (not uncommon in species described in the early days of paleontology).  You can't select a new type specimen (a lectotype) from topotype material (specimens from the same locality as the lost type) if there are multiple species or genera that all fit the original description.  Add to that the fact that early workers often kept very poor locality data or described species from glacial erratics of unknown origin, so you can't even identify topotype material.  All of this creates a catch-22 situation: the species name is legally valid in that at the time there was a holotype specimen and the (very poor) description was validly published, but today it is impossible to assign any new specimens to the species with any confidence because there is neither an existing type specimen nor a sufficient description to compare the specimens to. 

 

The only way out of the mess is to assign the name to the missing (or sometimes still existing but extremely poor and unidentifiable) type, and describe (with appropriate detail) a new species based on a good type specimen.  The old name is only "interesting reading" in the paper that describes (with discussion of the taxonomic reasoning) the new species.  Going forward, both the old name and the new name would appear on faunal lists for the formation, which (to the uninformed) would seem to slightly inflate the number of species in the formation.  The old name would be excluded from any modern revisions of the taxonomy, because there would be no characters to code in any phylogenetic analysis, though some mention would have to made of the fact that the name is unavailable to be used for new species.

 

Unfortunately though, on further thought, the approach would not be a good idea in the case of Dakotaraptor.  The type is not lost, it is embargoed.  That means if someone found new material and described a new species under a new name, the new name would always be at risk of becoming an invalid junior synonym if (or when) the Dakotaraptor steini holotype is "un-embargoed".  The situation is bad enough as it is, but it would be worse to deliberately create taxonomic confusion in order to "stick it" to the people who have put Dakotaraptor steini under (hopefully temporary) wraps.

 

Don

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Very informative, Don.  Thanks.

The human mind has the ability to believe anything is true.  -  JJ

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IMO there are two issues: resolving the "correct name" and getting a quality description of Hell Creek dromeosaur fossils that are available to study. If new material is also given a name and it turns out that they're the same thing as Dakotaraptor once the Dakotaraptor type becomes available for study, great. But if not, the information is out there. The "correct name" is really just a matter of bookkeeping.

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To be fair, it's not like synonymy issues would be anything vertebrate paleontologists would find novel or difficult to handle. (The same is true, though I think to a lesser extent, for invertebrate paleontologists.)

 

Don

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yep. personally, I find the nuts and bolts of taxonomic nomenclature to be tedious and I'm happy to let people who care more about the ins and outs of ICZN rules to do that qwork while I do the kinds of work that interests me.

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One of my favorite quotes comes from Rousseau Flower, one of the classic old school paleontologists.  In his monograph on the Montoya corals, after a long winding recounting of the tortured taxonomic history of one of the corals, he wrote "After all, paleontology should be about the study of fossils, not the study of names of fossils."

 

Don

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On 5/17/2021 at 9:00 AM, hadrosauridae said:

Nice "posts".  I liked the info, but twitter is a terrible medium for that type of posting or discussion.  

Using Thread Reader helps. Not perfect but better than nothing.

 

This probably won't help but there is additional limb bone material at the Carnegie Museum from Lance Creek which includes some dromaeosaurid bones. Unfortunately, the rest could be anything. It's labelled in the collection as ornithomimid but friends in the know that I've shared pictures with from my visit in 2010 (or was it 2011?) have said it doesn't look as such and at least one person thought some of it looked like possible thescelosaur.

Edited by Nick G.
Note on some more fossils
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