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Hi, Richard, Deb, you're right, it is an optical illusion and yes, all the marks are hollows. Vesna, I think what you see is the reflection of the microscope's light. Sorry the light isn't really good. The bone isn't that dark either, it's more a dark brown than the black you can see here. (But I actually found these marks on burned bones of every stages, including calcinated bones. They are just smaller and less fitted for pictures). If anyone is interested, I could take more pictures (although to me there isn't really anything more too see). Best, Aurélie Le 23/04/2015 06:44, Deb Bennett a écrit : > Richard, run the enlarged photos up into Photoshop and then rotate them > 180 degrees. That should make the optical illusion go away. > > And yes, I agree about the vivianite -- its patterns are always > Mandelbrotian. Cheers -- Deb Bennett > >> I think there is an optical illusion with the enlarged photos, where the >> marks look to me like upside down cups on the surface of the bone. >> >> In the image that includes three bones, the marks look like hollows. >> >> Am I correct in assuming that all the marks are hollows in the bone? >> >> I have seen vivianite on bones ranging from the late Pleistocene to recent >> mass graves. The crystals I saw were always jagged, not rounded. >> >> Richard Wright >> >> >> >> -------- Original Message ---------- >> >> Hello all, >> maybe a mineral, instead of an insect? >> It seems to me, looking at the last three pictures, that there is a >> blue powdery substance between cupules. It reminds me on vivianite, a >> mineral that gains this kind of deep blue color by oxidation; it is >> found often related to organic matter, including fossil bones. I found >> it on fragmented bones in a Serbian cave, in a Pleistocene layer. The >> most famous vivianite occurrence is "Blue Babe", the carcass of a >> steppe bison found at Alaska, and nick-named after the blue coating of >> this mineral. >> best regards, Vesna >> 2015-04-22 15:09 GMT+02:00 Jean-Bernard Huchet : >> Dear Aurlie, >> Really interesting find. A student from my laboratory submitted me a >> long bone fragment from Brazil showing exactly the same kind of >> modification on surface. >> In any case, these "cupules" are not dermestid pupal chambers and do >> not result from subterranean termites action. >> >> ....but the problem still has not been resolved :( >> >> Good luck, >> Kindest regards, >> Jean-Bernard >> >> Dr Jean-Bernard Huchet, PhDUMR 7209, Archozoologie, Archobotanique >> Socits, pratiques et environnements Musum national d'Histoire >> naturelle CP 56, 55 rue Buffon 75005 Paris - France Tel: 33(01) 40 79 >> 32 74 [log in to unmask] [2] >> Musum national d'Histoire naturelle, Institut de Systmatique, >> Evolution et Biodiversit ISYEB, UMR 7205 CNRS MNHN UPMC EPHE CP 50 >> (Entomologie), 75231 Paris Cedex 05 - France >> UMR 5199 du CNRS, PACEA Anthropologie des populations passes et >> prsentes Universit de Bordeaux Bt. B 8, alle Geoffroy St Hilaire, CS >> 50023 33615 Pessac Cedex - France Tel: 33(05) 40 00 25 48 >> [log in to unmask] [3] >> >> ======================================== >> >> Message du : 22/04/2015 11:00 >> De : "Aurelie Guidez " >> A : [log in to unmask] [5] >> Copie : >> Sujet : Re: [ZOOARCH] Strange little makrs >> >> Hi all, >> >> First, thank you for your ideas, to everyone who took the time to >> take a look at my mistery. >> >> I had already thought about insect pupation chambers but the >> regularity, number and size of my marks made me dismiss that idea. >> From what I saw in the various paper references you indicated, I think >> they are too small and too superficial, and so am still not convinced. >> >> As for a chemical corrosion explanation, I agree with you Richard. As >> I told Christian, I didn't go that way because of the regularity of >> the marks but would be more than ready to explore that lead if anyone >> could provide an example of such a phenomenon. >> >> Richard, I couldn't find the article you mentionned, but from the >> extract and the image you included, I must say I have the same >> objections as above. The marks on my bones are very rarely above 1mm >> in diameter, and when they are, it seems like the fusion of two too >> close pits. They are also never more than 1-1,5 mm deep. That will >> also answer your question. What you probably see on the bone in the >> right of the picture are some pits whit sharper edges. They create a >> shadow that make it look like it's deeper but it's not. >> >> I'm not giving up! I hope I'll fing a suitable explanation. If anyone >> has an other idea, please share, I'll consider any and every lead! >> >> Cheers, >> >> Aurlie. >> >> -- >> Aurlie Guidez >> Doctorante - PhD Student >> [log in to unmask] [6] >> [log in to unmask] [7] >> [8] >> UMR 7044 - Archimde >> Ostothque du Muse Zoologique de Strasbourg >> 29 boulevard de la Victoire >> F - 67000 Strasbourg >> http://archimedeunistra.fr/membres/doctorants/aurelie-guidez/ [9] >> Le 22/04/2015 05:24, Richard Wright a crit : >> >> Aurlie I have never seen anything like the marks you illustrate. They >> are a challenge. Christian suggests the possibility of chemical >> corrosion. My problem is that I can't see what corrosive agent could >> produce marks, in cortical bone, that were so consistent in shape and >> size, and separated from each other. So my bet is borings by some >> invertebrate organism. To that extent I agree with Adam's post >> suggesting dermestsid beetles. However your marks are virtually all >> roughly circular, and so do not mimic the elongated pupal chambers of >> dermestids. Interestingly, Hasiotis (Sedimentary Geology 167 (2004) >> 177-268) discusses borings on dinosaur bones that seem to closely >> resemble those you have. He describes them thus: START QUOTE (C) Small >> hemispherical borings on the surface of a femur of D4.18. Type >> 18--circular to elliptical borings in dinosaur bone, Fig. 13C-H >> Description: Predominantly circular to slightly elliptical in >> plan-view, the borings are preserved as molds and casts within the >> bone and are shallow hemispheres typically 0.01-4.0 mm deep. Some >> elliptical pits appear to be incomplete borings. The borings range >> from 0.5-1, 2.5-3, and 4-5.0 mm in diameter. Clusters of borings are >> random with no particular distribution between borings. Some skeletal >> elements contain both small and large borings, but one size always >> dominates the bone surface. Borings from different quarries have >> similar diameters, shapes, and distributions across bone surfaces. >> None of the dinosaur bones examined contain deep or fully penetrating >> holes or trails. Occurrence: Dinosaur bone borings were observed in >> quarries in the Brushy Basin Member in Colorado, Utah, and Wyoming. >> Tracemaker: The morphologies suggest that these borings were most >> likely produced by the larvae of carrion beetles (Coleoptera: >> Dermestidae) and are very similar to the traces of modern >> dermestids(Fig. 13G-H)." END QUOTE In case you can't get to Hasiotis's >> original article, there is an image of Fig. 13C at >> https://app.box.com/s/f1r7ece5menr1rucboe8kk50x7b7ez0v [10] A final >> question. Among the pits, are there any deeper borings that turn into >> tunnels that are perpendicular to the surface of the cortical bone? In >> the image with three separate bones, I wondered whether this was the >> case for some of the marks on the bone on the right. Please let us >> know if you solve this intriguing problem. Richard Wright >> >> -- >> *** >> Prof.dr Vesna Dimitrijevi >> Laboratory for Bioarchaeology, Department of Archaeology Faculty of >> Philosophy, University of Belgrade ika Ljubina 18-20, 11000 Belgrade >> Serbia >> >> http://filozofskifakultetbeograd.academia.edu/VesnaDimitrijevic [11] >> >> https://www.researchgate.net/profile/Vesna_Dimitrijevic/publications >> [12] >> >> http://bioarchlab.org [13] >> >> >> >> Links: >> ------ >> [1] mailto:[log in to unmask] >> [2] mailto:huchet@mnhnfr >> [3] mailto:[log in to unmask] >> [4] mailto:[log in to unmask] >> [5] mailto:[log in to unmask] >> [6] mailto:[log in to unmask] >> [7] mailto:[log in to unmask] >> [8] http://www.unistra.fr >> [9] http://archimede.unistra.fr/membres/doctorants/aurelie-guidez/ >> [10] https://app.box.com/s/f1r7ece5menr1rucboe8kk50x7b7ez0v >> [11] http://filozofskifakultetbeograd.academia.edu/VesnaDimitrijevic >> [12] >> https://www.researchgate.net/profile/Vesna_Dimitrijevic/publications >> [13] http://bioarchlab.org/ >> >> >> >>