sixgill pete Posted June 10, 2013 Share Posted June 10, 2013 I am wondering if any of you guys or gals know of any good resourced for ID'ing Lee Creek Dolphin, Porpoise and Whale teeth? Dolphin teeth I understand are conical shaped and porpoise are more blade shaped. But what about to the species level. I am sure there are more than 1 species of dolphin and porpoise found there. Is it even possible to identify them down to the species level? Bulldozers and dirt Bulldozers and dirt behind the trailer, my desert Them red clay piles are heaven on earth I get my rocks off, bulldozers and dirt Patterson Hood; Drive-By Truckers May 2016 May 2012 Aug 2013, May 2016, Apr 2020 Oct 2022 Link to comment Share on other sites More sharing options...
siteseer Posted June 10, 2013 Share Posted June 10, 2013 Sixgill Pete, You need this volume: Ray, C.E., D.J. Bohaska, I.A. Koretsky, L.W. Ward, and L.G. Barnes. (eds.) 2008.Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication No. 14. Virginia Museum of Natural History Publications. It is the fourth volume in the series on Lee Creek paleontology. It covers mammals and updates the other three volumes. It shows a variety of whale teeth. You can order it through the Virgina Museum. Jess I am wondering if any of you guys or gals know of any good resourced for ID'ing Lee Creek Dolphin, Porpoise and Whale teeth? Dolphin teeth I understand are conical shaped and porpoise are more blade shaped. But what about to the species level. I am sure there are more than 1 species of dolphin and porpoise found there. Is it even possible to identify them down to the species level? 1 Link to comment Share on other sites More sharing options...
cowsharks Posted June 10, 2013 Share Posted June 10, 2013 I have to go back and look at my copy of that volume to review the marine mammals section again. Compared to the numerous publications on fossil shark teeth there appears to be very little for fossil marine mammals, especially their teeth. This has been very frustrating for me because I know I have some pretty awesome fossil specimens from Calvert Cliffs and I have no resources for getting any ID's it seems. I've shown the specimens to folks at the Smithsonian, but it seems the specimens I have might be so rare that not much info is known about them; I realize this isn't the Smithsonian's fault, but nonetheless frustrating because I have specimens without a name/ID. I hate labeling everything with generic names like Dolphin, Whale, etc. Link to comment Share on other sites More sharing options...
siteseer Posted June 11, 2013 Share Posted June 11, 2013 Yeah, I have the same problem with Sharktooth Hill whale teeth large and small. With sharks you can often ID them to species but some are difficult-to-impossible to pin down. Whales tend to be distinguished by skull features other than teeth. I have a few teeth that would seem to belong to an uncommon whale but they could be just a less common tooth form of a common whale. In that fourth Lee Creek volume there is a photo of several modern sperm whale teeth, all belonging to one species and yet some of the teeth are dissimilar. We might expect the teeth to be more like each other instead, becoming more reduced to a simpler shape over time (a tendency in toothed whales) especially since the adult sperm whale has teeth only in the lower jaw. It boils down to a human expectation that everything in nature should be able to be neatly categorized like the manufactured things we collect. I have to go back and look at my copy of that volume to review the marine mammals section again. Compared to the numerous publications on fossil shark teeth there appears to be very little for fossil marine mammals, especially their teeth. This has been very frustrating for me because I know I have some pretty awesome fossil specimens from Calvert Cliffs and I have no resources for getting any ID's it seems. I've shown the specimens to folks at the Smithsonian, but it seems the specimens I have might be so rare that not much info is known about them; I realize this isn't the Smithsonian's fault, but nonetheless frustrating because I have specimens without a name/ID. I hate labeling everything with generic names like Dolphin, Whale, etc. Link to comment Share on other sites More sharing options...
Boesse Posted June 11, 2013 Share Posted June 11, 2013 I have one piece of advice for you: prepare for failure and disappointment. The general attitude amongst marine mammal researchers is that, with the exception of really distinctive species, isolated odontocete teeth are generally not identifiable even to the genus level, and often not even to the family level. This is due to the issue that Siteseer brought up above - that there is a tremendous amount of variation in modern odontocete dentitions. Second, the distinction between species is effectively non-existent between modern odontocetes. Sure, if you have a freak like a Mesoplodon, Monodon, Phocoena, Inia, Kogia, or Orcinus it is possible to identify Pliocene specimens - but different species of modern Delphinus, Stenella, Tursiops - different species of fossil kentriodontids or platanistoids - there's zero hope. Odontocete teeth do not preserve the same breadth of diagnostic information that shark teeth have. Pinniped and sirenian teeth, on the other hand, are generally identifiable to the genus level. 1 Link to comment Share on other sites More sharing options...
RichW9090 Posted June 11, 2013 Share Posted June 11, 2013 Bobby is spot on. Of course, that didn't stop many of the early (and, unfortunately a few of the present day) paleontologists from attaching a name to each isolated tooth or isolated, fragmented, water-worn vertebra of a cetacean that they found. Just because there exist such species names, doesn't mean that those species are actually diagnosable. 1 The plural of "anecdote" is not "evidence". Link to comment Share on other sites More sharing options...
cowsharks Posted June 11, 2013 Share Posted June 11, 2013 (edited) I have one piece of advice for you: prepare for failure and disappointment. The general attitude amongst marine mammal researchers is that, with the exception of really distinctive species, isolated odontocete teeth are generally not identifiable even to the genus level, and often not even to the family level. This is due to the issue that Siteseer brought up above - that there is a tremendous amount of variation in modern odontocete dentitions. Second, the distinction between species is effectively non-existent between modern odontocetes. Sure, if you have a freak like a Mesoplodon, Monodon, Phocoena, Inia, Kogia, or Orcinus it is possible to identify Pliocene specimens - but different species of modern Delphinus, Stenella, Tursiops - different species of fossil kentriodontids or platanistoids - there's zero hope. Odontocete teeth do not preserve the same breadth of diagnostic information that shark teeth have. Pinniped and sirenian teeth, on the other hand, are generally identifiable to the genus level. Bobby, does this mean that ID's such as cf.Tretosphys ("c" in first image) and Ninoziphius cf platyrostris ("e" in second image) are too specific and possibly inaccurate? These come from the elasmo.com Lee Creek trips section for previous years. Edited June 11, 2013 by cowsharks Link to comment Share on other sites More sharing options...
cowsharks Posted June 11, 2013 Share Posted June 11, 2013 Don, I know it doesn't have much in it by way of tooth illustrations, but there's a decent book that compares the skeletal anatomy of Dolphins and Seals : http://www.buriedtreasurefossils.com/images_Literature/Seal-Dolphin%20Book.jpg I bought mine through the Aurora Fossil Museum for $25 or so. I've used it to help identify various bones that I've found along Calvert Cliffs. All of the illustrations are line drawings - no actual photographs. Daryl. 1 Link to comment Share on other sites More sharing options...
Boesse Posted June 11, 2013 Share Posted June 11, 2013 Rich - Excellent point. I cannot overemphasize that even professional researchers do not trust the old literature. Many paleontologists used to name fossil cetaceans just off teeth ("Scaldicetus"), vertebrae (Zarhachis), and earbones (e.g. all the Sharktooth Hill odontocetes), and it has made navigating cetacean paleontology like walking a minefield. Some names are still in use - Zarhachis had distinctive vertebrae, and a good skeleton with a beautiful skull has been treated ever since as the de facto holotype/neotype, problems of establishing a vertebra as a holotype notwithstanding. Under ICZN rules you can establish anything as a holotype even if it's undiagnostic. Siteseer - excellent question. Tretosphrys is one of the 'freaks', so to speak, and is probably a diagnosable critter; we just don't have a skull yet, but I believe there are a couple of jaw fragments with those teeth. It's the rest of the odontocetes with simple crowns you gotta watch out for. As for Ninoziphius, that is probably a little less reliable as Messapicetus gregarius from the mid-late Miocene also has weird roots like that with a similarly shaped crown. Again, this reinforces what I was taught as a young paleontologist: question the accuracy of every fossil identification, even if made by someone of authority in the field. Bobby 1 Link to comment Share on other sites More sharing options...
mako-mama Posted June 15, 2013 Share Posted June 15, 2013 The main basis for ID for the Ninoziphis tooth was the fact the root was square. In Messapicetus the roots are more flattened and the few teeth I've seen are considerably larger. Given the huge variety of cetacean teeth found at Aurora, I've since learned to sort by "tooth type" until a skull is found ;-) Link to comment Share on other sites More sharing options...
Boesse Posted June 15, 2013 Share Posted June 15, 2013 Pat, I understand that you have to work with whatever you are left with. To be honest, however, a recent paper on Ninoziphius by Olivier Lambert, G. Bianucci, and C. Muizon indicates that the Lee Creek ziphiid material may not be correctly identified as Ninoziphius. My points above are that it is not really always possible to identify odontocete teeth even to the family level. No two teeth of Mesappicetus gregarius are identical; there are about four or five teeth, and all of them look different (Bianucci et al. 2010: fig. 10). Link to comment Share on other sites More sharing options...
mako-mama Posted June 16, 2013 Share Posted June 16, 2013 Thanks, Bobby! As I stated, I now only sort by type and advise others to do the same-short of having the skull in view. Sadly, it is my experience that many useful skulls end up in the possession of casual fossil collectors who are unwilling to donate them. They end up as curiosities in someone's fossil shed--and we all suffer the lack of knowledge that could be gained. Yeah, parking lot reporting isnt always a dependable source of info. Link to comment Share on other sites More sharing options...
non-remanié Posted June 16, 2013 Share Posted June 16, 2013 This topic should be pinned for Bobby's sake! ---Wie Wasser schleift den Stein, wir steigen und fallen--- Link to comment Share on other sites More sharing options...
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