piranha Posted March 13, 2015 Share Posted March 13, 2015 On 7/18/2013 at 4:57 PM, Auspex said: This does look like oolites. But, the joke begs the question: have trilobite eggs ever been identified? Anyone know? This great question from Auspex a couple years ago can now be answered in the affirmative. Up until now there have been a few close calls but nothing conclusive. The earliest reference to alleged trilobite eggs was made by Joachim Barrande in 1872. C.D. Walcott also published a brief paper in 1877 and each of these were subsequently disproved by Percy Raymond in 1931. Zhang and Pratt 1994 also reported on possible eodiscid embryos but had to concede that they may have been produced by another soft-bodied arthropod. Now at long last we finally have what appear to be bona fide trilobite eggs. Not surprisingly, the remarkable preservation of pyritized Triarthrus specimens from New York have yielded this highly anticipated fossil gold. Pun intended, Enjoy! PYRITIZED IN SITU TRILOBITE EGGS FROM THE ORDOVICIAN OF NEW YORK (LORRAINE GROUPE): IMPLICATIONS FOR TRILOBITE REPRODUCTIVE BIOLOGY Hegna, Thomas, Martin, Markus, Soriano, Carmen (2015) Geological Society of America - North-Central Section - 49th Annual Meeting (May 19-20) Paper No. 20-3 - Presentation Time: 8:45 AM Despite a plethora of exceptionally preserved trilobites, trilobite reproduction has remained a mystery. No trilobite has preserved unambiguous eggs or genitalia. This study reports on the first occurrence of preserved, in situ trilobite eggs from Triarthrus eatoni from the Lorraine Group in upstate New York. Like other exceptionally preserved trilobites from the Lorraine Group, the trilobites are replaced with pyrite on their exoskeletons and ventral appendages. The eggs (presumably representing unfertilized eggs) are spherical to elliptical in shape, about 50 µm in size, and are clustered in the genal area of the cephalon near the lateral border. The eggs are only visible ventrally with no dorsal brood pouch or recognized sexual dimorphism. This location is consistent with how modern horseshoe crabs carry their unfertilized eggs. Trilobites likely released their gametes (eggs and sperm) through a genitalia pore of as-yet unknown location (likely near the posterior boundary of the head). If T. eatoni’s reproductive biology is representative of other trilobites, they spawned rather than mated and exhibited r-strategy reproduction. A more detailed view of the anatomy associated with the eggs in currently in progress with synchrotron x-ray tomography. Barrande, Joachim (1872) Systême Silurien du centre de la Bohême. 1 ère Partie. Recherches paléontologiques, Supplement au Vol.I: Trilobites, Crustaces divers et Poissons, (Prague and Paris) Walcott, C.D. (1877) Note on the Eggs of the Trilobite. Annual Report of the New York State Museum of Natural History, 31:66-67 Raymond, P.E. (1931) Capsule-shaped "Eggs" In: Notes on invertebrate fossils, with descriptions of new species. Bulletin of the Museum of Comparative Zoology, 55:165-213 Zhang, X.G., & Pratt, B.R. (1994) Middle Cambrian arthropod embryos with blastomeres. Science, 266:637-639 11 Link to comment Share on other sites More sharing options...
Auspex Posted March 13, 2015 Share Posted March 13, 2015 I have wondered about this ever since I first learned what trilobites were... What a discovery! "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
xonenine Posted March 13, 2015 Share Posted March 13, 2015 amazing, and NY, no less...another fossil goes on the bucket list "Your serpent of Egypt is bred now of your mud by the operation of your sun; so is your crocodile." Lepidus Link to comment Share on other sites More sharing options...
Raggedy Man Posted March 13, 2015 Share Posted March 13, 2015 Fascinating ...I'm back. Link to comment Share on other sites More sharing options...
izak_ Posted March 14, 2015 Share Posted March 14, 2015 Wow... A-mazing... Thanks for sharing. Link to comment Share on other sites More sharing options...
Herb Posted March 14, 2015 Share Posted March 14, 2015 WOW! any pix? "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
piranha Posted March 14, 2015 Author Share Posted March 14, 2015 WOW! any pix? According to the abstract it sounds like the images are still in the works. Hopefully a published paper is coming soon as well. A more detailed view of the anatomy associated with the eggs is currently in progress with synchrotron x-ray tomography. Link to comment Share on other sites More sharing options...
Ludwigia Posted March 14, 2015 Share Posted March 14, 2015 A logical assumption has finally been verified. It should certainly be interesting to read a published paper about it. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
Malcolmt Posted March 14, 2015 Share Posted March 14, 2015 Way to go Markus!!!!!!! If eggs were to be found a good place to look would have been on his "goldbugs" Link to comment Share on other sites More sharing options...
Triceratops Posted March 15, 2015 Share Posted March 15, 2015 Very interesting! Thanks for sharing. -Lyall Link to comment Share on other sites More sharing options...
Scylla Posted March 17, 2015 Share Posted March 17, 2015 That is sooo cool! Link to comment Share on other sites More sharing options...
piranha Posted January 27, 2016 Author Share Posted January 27, 2016 While looking for some unrelated material I stumbled across additional info on the alleged trilobite eggs from Zhang & Pratt 1994. Evidently they were found to be worm eggs. It's also worth mentioning that Zhang & Pratt agree as co-authors of this recent paper: Quote The first phosphatized embryos were recovered from the middle Cambrian (Stage 5) Gaotai Formation in Duyun (Zhang and Pratt, 1994). Completely unexpected, these stirred considerable excitement and provoked a worldwide search for embryos in comparable limestones. The minute embryos were initially presumed to be of arthropod affinity because they occurred with many phosphatized eodiscoid trilobite protaspides—the only larval form in the same strata. However, a number of prehatching ‘egg-larvae’ (Fig. 2A and B , including Markuelia coiled within their egg membranes, were subsequently discovered from the original limestone bed (Zhang et al., 2011). These are oblate spheroid-shaped, and are roughly the same size as other known cleavage embryos (Fig. 2C). Thus the postulated trilobite affinity for the original specimens is incorrect and, rather, they belong to this scalidophoran worm taxon. Shen, C., Pratt, B.R., Lan, T., Hou, J.B., Chen, L., Hao B.Q., & Zhang, X.G. (2013) The search for Orsten-type fossils in southern China. Palaeoworld, 22:1-9 Link to comment Share on other sites More sharing options...
Raggedy Man Posted January 28, 2016 Share Posted January 28, 2016 While looking for some unrelated material I stumbled across additional info on the alleged trilobite eggs from Zhang & Pratt 1994. Evidently they were found to be worm eggs. It's also worth mentioning that Zhang & Pratt agree as co-authors of this recent paper: So my question is, did the eggs settle by the trilobite or were they purposely laid on the trilobite so when they emerge a food source was immediately available? ...I'm back. Link to comment Share on other sites More sharing options...
Auspex Posted January 28, 2016 Share Posted January 28, 2016 So my question is, did the eggs settle by the trilobite or were they purposely laid on the trilobite so when they emerge a food source was immediately available? My gut instinct is the latter, but we'll probably never know. It is possible too that the trilobite was there to eat the eggs... "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
piranha Posted January 28, 2016 Author Share Posted January 28, 2016 On 1/28/2016 at 7:49 AM, Raggedy Man said: So my question is, did the eggs settle by the trilobite or were they purposely laid on the trilobite so when they emerge a food source was immediately available? On 1/28/2016 at 7:55 AM, Auspex said: My gut instinct is the latter, but we'll probably never know. It is possible too that the trilobite was there to eat the eggs... The worm eggs were not laid on or near a mature trilobite. The worm eggs were found associated with trilobite larvae: "The first description of Cambrian embryos was based on a few embryos of cleavage stages, which Zhang and Pratt (1994) had originally attributed to arthropods, presumably trilobites because eodiscoid protaspides were the only fossil larvae recovered in the same rocks." Zhang, X.G., Pratt, B.R., & Shen, C. (2011) Embryonic development of a middle Cambrian (500 myr old) scalidophoran worm. Journal of Paleontology, 85(5):898-903 1 Link to comment Share on other sites More sharing options...
piranha Posted January 13, 2017 Author Share Posted January 13, 2017 This highly anticipated paper has finally been published. Enjoy! Hegna, T.A., Martin, M.J., & Darroch, S.A. (2017) Pyritized in situ trilobite eggs from the Ordovician of New York (Lorraine Group): Implications for trilobite reproductive biology. Geological Society of America, Geology, 45(3):199-202 OPEN ACCESS PDF 5 Link to comment Share on other sites More sharing options...
Malcolmt Posted January 13, 2017 Share Posted January 13, 2017 Great paper been waiting to read. Amazing preservation no doubt what they are..... Link to comment Share on other sites More sharing options...
Missourian Posted January 14, 2017 Share Posted January 14, 2017 For some reason, the eggs in/near the trilobite's head reminded me of the 1980s B-movie 'Time Walker': https://www.youtube.com/watch?v=Zabhd3E8JDU Context is critical. Link to comment Share on other sites More sharing options...
piranha Posted January 14, 2017 Author Share Posted January 14, 2017 We have come a long way from the first alleged trilobite eggs reported by Barrande and Walcott in the 1800's. For an interesting historical perspective, here is Walcott's description and the subsequent rebuttal by Raymond. Walcott, C.D. (1877) Note on the Eggs of the Trilobite. Annual Report of the New York State Museum Natural History, 31:66-67 Raymond, P.E. (1931) Capsule-shaped "Eggs" In: Notes on invertebrate fossils, with descriptions of new species. Bulletin of the Museum of Comparative Zoology, 55:165-213 Link to comment Share on other sites More sharing options...
Ramon Posted January 14, 2017 Share Posted January 14, 2017 Wow!!! I didn't even know trilobites layed eggs. What a great discovery!!! "Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier Link to comment Share on other sites More sharing options...
piranha Posted January 27, 2017 Author Share Posted January 27, 2017 On 1/13/2017 at 10:23 AM, piranha said: This highly anticipated paper has finally been published. Enjoy! Hegna, T.A., Martin, M.J., & Darroch, S.A. (2017) Pyritized in situ trilobite eggs from the Ordovician of New York (Lorraine Group): Implications for trilobite reproductive biology. Geological Society of America, Geology, 45(3):199-202 OPEN ACCESS PDF 1 Link to comment Share on other sites More sharing options...
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