Laos dinosaur sacrum vertebra

[FF7_Yuffie]

Hello,

 

Thoughts on this? Associated and connected sacrum verts from Laos - Gres superieurs.

 

5 inch long. 

 

Seller id'd it as a ornithomimid, but was told it could be other theropod.

 

That formation just has a handful of species described. No ornithomimids. 

 

But is anyone able to take a look and shed some light. Ornithomimid, raptor, even juvenile ichthyovenator etc.

 

If ornithomimid, it would be an entirely new species? With none described from there or the equivalent Khok Kruat Formation?

 

 

[pachy-pleuro-whatnot-odon]

Can't really answer your question, but just wanted to advocate caution in assuming that if this were ornithomimid in a formation where none have previously been described (even if also the case in an equivalent formation), this automatically must be a new species. For although there seems to be a general trend in palaeontology these days to split animals into species based on presumed regional differences, you should keep in mind that a sufficiently sized dataset is required to properly rule out individual variation. And that's in addition to the general difficulties involved with taxonomy. For, on-going research is coming to the realisation that there's a discrepancy between genetic and anatomical affiliation, with the latter being vulnerable to the influences of convergent evolution, and the former being closer to what our current definition of speciation would be - that is, a species broadly consists of similar-looking animals that are able to produce viable offspring together, irrespective of the specific populations from which the parent animals derive. This has profound implications for how we apply taxonomic classification to the palaeontological record, although I doubt these ideas have made their way into that field yet.

[Sagebrush Steve]

14 hours ago, pachy-pleuro-whatnot-odon said:

…a species broadly consists of similar-looking animals that are able to produce viable offspring together, irrespective of the specific populations from which the parent animals derive. This has profound implications for how we apply taxonomic classification to the palaeontological record, although I doubt these ideas have made their way into that field yet.

Yes, this is something that has confounded me for decades.  The definition a biologist uses for “species” is vastly different from what a paleontologist uses.  Apparently because there is no way to prove whether two similar-looking fossil animals could produce viable offspring, the tendency seems to be to declare a new species every time a fossil is found that is even slightly different from the existing fossil record.  (Yes, I know that is an oversimplification but not by as much as some people would have you believe.)  Given the biological definition of “species,” maybe fossils should not be classified as species at all, but given a new name similar to how fossil footprints are not assigned to an animal species but rather to a separate “ichnospecies”.

[Troodon]

Not sure you will be able to put any identifier on this sacrum.  Its a nice peice from a cool location.  Nice to have in any collection even though its indeterminate.

[pachy-pleuro-whatnot-odon]

7 hours ago, Sagebrush Steve said:

Given the biological definition of “species,” maybe fossils should not be classified as species at all, but given a new name similar to how fossil footprints are not assigned to an animal species but rather to a separate “ichnospecies”.

 

That's an interesting idea. However, I'm having a bit of difficulty envisioning how this would help academic research. That's because while for collectors it's often enough to stick a cool sounding label on a fossil that will help define its general place in (pre)history, the idea behind palaeontology, as I understand it, is much more to extend the biological sciences into the past to inform us on the broad history of life on earth. Take away or simplify the taxonomic tools, and you greatly reduce palaeontology's scientific utility.

 

That having been said, one may, of course, ask what value the current palaeontological paradigm towards speciation provides over that of a "fossilitaxa", especially since palaeontology's existing contributing value to the biological sciences hasn't, to my knowledge, ever been evaluated under the terms discussed here. I do, however, agree that the way everything is split off into its own species (and sometimes genus) these days - though much needed to get rid of wastebucket-taxons - seems counterproductive to the biological pursuit by confusing our phylogenetic analyses with unverifiable and dubious detail. Call me a lumper, but I'd rather propose to maintain taxonomic classifications, but limit them to the generic level for fossil species/species for which no historic records exist.

 

The situation is quite different when you apply palaeontology with either a geological or commercial perspective, as in these cases it's actually beneficial to acknowledge as many different species as possible. In commerce, more species, quite simply and directly, equates to more sales; whereas in geology splitting has its benefit over lumping, especially if the distinctions can be stratigraphically tied, since here the main purpose is biostratigraphy, aimed at quickly identifying the most promising layers for economic exploitation (e.g., oil). As such, I think the situation surrounding taxonomy in palaeontology is a good example of why a discipline can't ever properly serve multiple masters... But that's just my opinion, of course.