Straus Posted March 12, 2010 Share Posted March 12, 2010 I found this jaw bone segment on the Oregon coast. It is about 3 1/2 inches long, 2 1/4 inches high and 3/4 inch deep (not including the rock matrix on back). It has four molars. They are slightly transluscent, almost like agate. One molar is filled with crystals. I would love to learn anything I can about this fossil. What animal is it from? Seal? Sea lion? Are the teeth agatized? If so, does that indicate anything about the age of the fossil? There is a thin layer of rock covering the front of the jaw bone. should we try to clean that off to expose the bony material? If so, how? Any info that you would like to share would be so appreciated. We are very new to this, and really excited! Link to comment Share on other sites More sharing options...
TourmalineGuy Posted March 12, 2010 Share Posted March 12, 2010 Wow, that's really awesome. May I ask where you found it on the coast? I just moved to Oregon, myself, and have read a lot about the coastal geology lately, so I may be able to help. You have a few options and the teeth aren't in great shape so that makes it more difficult. But it reminds me a lot of Desmostylus Hesperus. An ancient "sea-hippo." If so, that is quite an incredible find! http://fingerlakesfossilfarm.org/mammal_images/desmostylus_teeth-01.jpg Here is an example of some stray unbroken teeth in matrix http://www.rockpow.com/images2/seacowmed.jpg Here is another. Was it found in the Newport area? If so, that's almost surely what it is, the teeth just don't look like any of the other local fauna. Seal and Sea Lion teeth are quite different. Also, it seems to have the cylindrical cross section of the desmostylus... Very cool Edit: Oh yeah, to help with your questions. If I am correct (wait for some others to agree). Desmostylus Hesperus is between 10-30 Million Years old. The teeth are probably not agatized, the coloring is likely just a feature of how the enamel was preserved. And the crystals may just be pieces of sand, check carefully, its hard to tell from the pics. I wouldn't try to expose the bone more, at least until you show it to someone more expert. Oh and the Portland area Paleontology group, NARG, would love for an opportunity to see this, I'm sure. http://www.narg-online.com/index.htm They meet on the first Wednesday of every month in the Beaverton area. Link to comment Share on other sites More sharing options...
Harry Pristis Posted March 12, 2010 Share Posted March 12, 2010 Unlikely to be Desmostylus because of the uniformity and number of the teeth -- too many teeth, too uniform in size. It appears that you have a maxilla of something with the enamel crowns sheared off. In other words, it seems that you have a piece of upper jaw with only roots remaining. I might have a guess if this were a Florida specimen from a known time, but no guesses on Oregon fossils. Maybe Bobby can help you. http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
Boesse Posted March 12, 2010 Share Posted March 12, 2010 Hmm... interesting. There are other desmostylians from Oregon, including Cornwallius, and Behomotops (or perhaps it's only from Washington). Either way, this specimen may not have enough of the crowns preserved for proper ID, but I'm going to email this page to my friend Dr. Brian Beatty, who is currently studying NE pacific Desmostylians (including Oregonian Cornwallius). I'm also interested to hear where this came from; there are Oligocene through late Miocene vertebrate bearing units on the Oregon coast. Bobby Link to comment Share on other sites More sharing options...
Straus Posted March 12, 2010 Author Share Posted March 12, 2010 Wow, that's really awesome. May I ask where you found it on the coast? I just moved to Oregon, myself, and have read a lot about the coastal geology lately, so I may be able to help. You have a few options and the teeth aren't in great shape so that makes it more difficult. But it reminds me a lot of Desmostylus Hesperus. An ancient "sea-hippo." If so, that is quite an incredible find! http://fingerlakesfossilfarm.org/mammal_images/desmostylus_teeth-01.jpg Here is an example of some stray unbroken teeth in matrix http://www.rockpow.com/images2/seacowmed.jpg Here is another. Was it found in the Newport area? If so, that's almost surely what it is, the teeth just don't look like any of the other local fauna. Seal and Sea Lion teeth are quite different. Also, it seems to have the cylindrical cross section of the desmostylus... Very cool Edit: Oh yeah, to help with your questions. If I am correct (wait for some others to agree). Desmostylus Hesperus is between 10-30 Million Years old. The teeth are probably not agatized, the coloring is likely just a feature of how the enamel was preserved. And the crystals may just be pieces of sand, check carefully, its hard to tell from the pics. I wouldn't try to expose the bone more, at least until you show it to someone more expert. Oh and the Portland area Paleontology group, NARG, would love for an opportunity to see this, I'm sure. http://www.narg-online.com/index.htm They meet on the first Wednesday of every month in the Beaverton area. Hi, new at this and messed up on first attempt to reply, which is why one response is posted twice. Anyway, thank you guys so much for your responses. Now I am more curious than ever, and I will contact NARG. I found this out of Coos Bay, Oregon. It is supposed to be a Pliocene area. The teeth only appear about 1/4 inch above the jaw bone ridge, The third molar really does appear to be filled with crystal, not sand but the photo is not great. If anyone is interested I will try to shoot it again for more detail. I am not going to try to clean it my self. Did anyone happen to look at my other post? Bone or rock? Thank you for sending photos to friend, I will be very excited to hear what they have to say. Link to comment Share on other sites More sharing options...
MOROPUS Posted March 12, 2010 Share Posted March 12, 2010 Could it be a primitive eroded horse jaw section? By the way, that`s a veeery nice and rare piece of fossil! You are very lucky to came across something like that! Link to comment Share on other sites More sharing options...
Straus Posted March 12, 2010 Author Share Posted March 12, 2010 I can't lie, I was pretty tickled when I saw it and realized what it was! Will have to look up the horse idea to see if they were on the Oregon coast. Thanks. Link to comment Share on other sites More sharing options...
Straus Posted March 13, 2010 Author Share Posted March 13, 2010 I just did a little more research and the area where I found thise is considered miocene. I hope that helps us figure this out. Thanks again! Link to comment Share on other sites More sharing options...
TourmalineGuy Posted March 13, 2010 Share Posted March 13, 2010 Very unlikely to be part of horse, but not beyond the realm of possibility... That would be very cool. Looking through the book "Oregon Fossils" the only listed marine mammal (in this book) from Coos Bay is a walrus. Anyone have some walrus teeth to compare...? Link to comment Share on other sites More sharing options...
Boesse Posted March 13, 2010 Share Posted March 13, 2010 DEFINITELY not a pinniped, especially not the pinnipeds from the Empire Fm., which are all (mostly) unpublished. Bobby Link to comment Share on other sites More sharing options...
Beatty Posted March 13, 2010 Share Posted March 13, 2010 If it is a desmostylian, it would have to be a very young one, a juvenile individual. But the thin nature of the mandible, seen from the broken end, is not too characteristic of desmostylians, even young ones. I would suggest that it is a terrestrial mammal of some sort. Without the crowns, or better details of the formation it came from, it is really hard to tell what it is. The roots are similar in shape to desmostylians, but that can be said for animals a number of large terrestrial mammals as well. It might be from a young entelodont, perissodactyl, or a number of other "ungulates". Still, this is encouraging, and the place it came from is certainly worth going back to.... Brian Beatty Asst. Professor, Dept Anatomy New York College of Osteopathic Medicine Old Westbury, NY 11568 and Managing Editor, PalArch's Journal of Vertebrate Palaeontology www.palarch.nl Link to comment Share on other sites More sharing options...
Guest Smilodon Posted March 13, 2010 Share Posted March 13, 2010 If it is a desmostylian, it would have to be a very young one, a juvenile individual. But the thin nature of the mandible, seen from the broken end, is not too characteristic of desmostylians, even young ones. I would suggest that it is a terrestrial mammal of some sort. Without the crowns, or better details of the formation it came from, it is really hard to tell what it is. The roots are similar in shape to desmostylians, but that can be said for animals a number of large terrestrial mammals as well. It might be from a young entelodont, perissodactyl, or a number of other "ungulates". Still, this is encouraging, and the place it came from is certainly worth going back to.... Just curious. How often have you seen desmostylian teeth still in the jaw? Link to comment Share on other sites More sharing options...
Straus Posted March 13, 2010 Author Share Posted March 13, 2010 Would it help at all if I did a detail sketch of the shape of the molar from top view? I know that the crowns are mostly gone, but I can still determine the structure. What information do you need about the formation? Link to comment Share on other sites More sharing options...
Boesse Posted April 2, 2010 Share Posted April 2, 2010 Just curious. How often have you seen desmostylian teeth still in the jaw? I think this will answer your question: http://www.bioone.org/doi/abs/10.1671/039.029.0320 Link to comment Share on other sites More sharing options...
Guest Smilodon Posted April 2, 2010 Share Posted April 2, 2010 I think this will answer your question: http://www.bioone.org/doi/abs/10.1671/039.029.0320 The article does not seem to answer my question. I was asking, generally - 5%, 25%, 50% of desmostylid specimens? My sense is, very rarely. Link to comment Share on other sites More sharing options...
Boesse Posted April 2, 2010 Share Posted April 2, 2010 The link to that article was to illustrate that Brian is already an authority on desmostylian fossils, and he's probably seen close to all of the desmostylian jaws currently in museum collections. That being said... the answer to your question regarding the percentage of demostylian jaws: it's probably closer to 1%; most specimens are isolated teeth (i.e. the Sharktooth Hill Bonebed, and the Santa Margarita Sandstone). Bobby Link to comment Share on other sites More sharing options...
siteseer Posted April 2, 2010 Share Posted April 2, 2010 Unlikely to be Desmostylus because of the uniformity and number of the teeth -- too many teeth, too uniform in size. It appears that you have a maxilla of something with the enamel crowns sheared off. In other words, it seems that you have a piece of upper jaw with only roots remaining. I might have a guess if this were a Florida specimen from a known time, but no guesses on Oregon fossils. Maybe Bobby can help you. Harry, I think it could be a camel. Jess Link to comment Share on other sites More sharing options...
Guest Smilodon Posted April 2, 2010 Share Posted April 2, 2010 The link to that article was to illustrate that Brian is already an authority on desmostylian fossils, and he's probably seen close to all of the desmostylian jaws currently in museum collections. That being said... the answer to your question regarding the percentage of demostylian jaws: it's probably closer to 1%; most specimens are isolated teeth (i.e. the Sharktooth Hill Bonebed, and the Santa Margarita Sandstone). Bobby It's so hard to convey intention in the written word. I was not questioning the expertise of the person. I knew the answer already. My statement was meant to point out that the possibility of this being a desmostylid jaw was infinitesimally small to begin with. Taking the specimen's size into account made it nearly 0% unless it was very juvenile as he correctly pointed out. Lastly it looks nothing like I'd imagine that young desmostylid teeth would look like broken off that way. No criticism was intended at all. Link to comment Share on other sites More sharing options...
Guest Smilodon Posted April 2, 2010 Share Posted April 2, 2010 Interestingly, as I remember, it looks a lot like a dugong maxilla I once found in Florida with it's teeth broken off in a similar manner Link to comment Share on other sites More sharing options...
Harry Pristis Posted April 2, 2010 Share Posted April 2, 2010 Harry, I think it could be a camel. Jess Could be! It's difficult to rule out a number of artiodactyls -- there was a proliferation of 'em in the Miocene. I imagine there were a few, even in Oregon. http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
siteseer Posted April 2, 2010 Share Posted April 2, 2010 The link to that article was to illustrate that Brian is already an authority on desmostylian fossils, and he's probably seen close to all of the desmostylian jaws currently in museum collections. That being said... the answer to your question regarding the percentage of demostylian jaws: it's probably closer to 1%; most specimens are isolated teeth (i.e. the Sharktooth Hill Bonebed, and the Santa Margarita Sandstone). Bobby Bobby, I saw an unprepped Desmostylus skull in matrix (one side of the jaw and the two teeth visible) from where they excavated for that toll road in Orange County several years ago. That was cool to see. I haven't seen any jaw sections with teeth from the Monocline Ridge area where hundreds of teeth were found and were seen by the flat at Tucson in the 80's and into the 90's. You don't see too many these days. The teeth are rare in the Sharktooth Hill Bonebed. It might be safe to say that Bob Ernst found at least 30 complete teeth in his lifetime plus probably more than three times as many partial teeth but only two jaw sections with a tooth in it. The weird thing about the Santa Margarita Sandstone is that I've seen only one complete Desmostylus and a few partials from it but maybe twenty Palaeoparadoxia teeth, the latter being much rarer elsewhere. Desmostylus teeth break up after some transport but "Palaeos" are more solid and travel better. I have been told that much of what is found in the Santa Margarita was washed in from the south. That's why most of what you find is water-worn. Link to comment Share on other sites More sharing options...
Boesse Posted April 2, 2010 Share Posted April 2, 2010 It's so hard to convey intention in the written word. I was not questioning the expertise of the person. I knew the answer already. My statement was meant to point out that the possibility of this being a desmostylid jaw was infinitesimally small to begin with. Taking the specimen's size into account made it nearly 0% unless it was very juvenile as he correctly pointed out. Lastly it looks nothing like I'd imagine that young desmostylid teeth would look like broken off that way. No criticism was intended at all. Ya, that's the problem, sometimes you can mistake what someone's saying. No worries. Jess - LACM just finished preparing a nearly complete skeleton of a Paleoparadoxia from the Monterey Formation, which I believe is just missing the legs below the knees. Either way, it looks like a really incredible fossil. Which reminds me - Stan Jarocki may have the proximal end of a desmostylian femur from the Santa Margarita - it's pretty huge (and we can safely say it isn't from Dusisiren!). It's unfortunate that (if this specimen does indeed represent a land mammal) it's missing the crowns; this is almost undoubtedly from marine rocks, likely from the Empire Formation. Nonmarine tie-ins are always helpful (even if the Empire's age is already known via paleomag). Bobby Link to comment Share on other sites More sharing options...
Guest Smilodon Posted April 2, 2010 Share Posted April 2, 2010 It might be safe to say that Bob Ernst found at least 30 complete teeth in his lifetime plus probably more than three times as many partial teeth but only two jaw sections with a tooth in it. I wonder where they are now? (Hint - one of them is in Florida now, and one is Delaware. ) Link to comment Share on other sites More sharing options...
Straus Posted April 2, 2010 Author Share Posted April 2, 2010 Thank you all so much for trying to help me identify this. It's killing me, I want to find out so bad. Is there anything else that would help give a difinitive answer? Better photo of a specific area? Detail sketch? It was found in the Empire Formation. Whether or not I ever get the answer, I have so appreciated everybodies input. If I ever do find out (ie take it to professor Orr at U of O) I will post what he says. Link to comment Share on other sites More sharing options...
Straus Posted April 2, 2010 Author Share Posted April 2, 2010 Hi again. I was able to take some much improved photos of this fossil. I hope these will be of further help in an identification. I have also sent these photos to the Oregon Proffesor who is an expert. I'll let you know if I hear back from him. In the mean time, here are some better detail shots. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.