Still_human Posted December 8, 2018 Share Posted December 8, 2018 Does anyone have any fossils of, or with anomalocaris BODIES? I'm interested in seeing what they look like. I did searches for them and they all look so random, without any features except for the overlapping ends. Even the beautiful full-animal fossils have bodies like that. Did they always fossilize so unimpressively? Link to comment Share on other sites More sharing options...
Thecosmilia Trichitoma Posted December 8, 2018 Share Posted December 8, 2018 I thought that some of them were quite nice. However, even the Burgess Shale has limitations, and a perfectly preserved fossil can be very rare. They are actually quite amazing as they stayed buried safely for 508 million years. Here is one of the better ones that I have seen online. 1 It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt -Mark Twain Link to comment Share on other sites More sharing options...
Pumpkinhead Posted December 8, 2018 Share Posted December 8, 2018 If you want to see some really glorious stuff I would recommend checking out the ROM's website. Thecosmilia's picture is actually Opabinia, which will appear similarly jumbled as both Anomalocaris and Opabinia have non mineralized skeletons and were deposited rapidly in the case of the Burgess Shale. Considering the poor durability of the original animals these specimens are really quite beautiful and exquisitely preserved 2 Link to comment Share on other sites More sharing options...
Still_human Posted December 14, 2018 Author Share Posted December 14, 2018 On 12/8/2018 at 5:26 PM, Thecosmilia Trichitoma said: I thought that some of them were quite nice. However, even the Burgess Shale has limitations, and a perfectly preserved fossil can be very rare. They are actually quite amazing as they stayed buried safely for 508 million years. Here is one of the better ones that I have seen online. That's the thing, they might BE perfectly preserved! I just don't know exactly what their body IS, and how it would look when perfectly fossilized. If it's squishy, which I think it's supposed to be, or at least softer than the rest, then maybe the best it could ever be preserved is the relatively undetailed mass that it appears as in the fossils that perfectly preserved the rest of the animal. That's what I was hoping to find out--if there are any fossils with the body mass having a more visible structure. Link to comment Share on other sites More sharing options...
Still_human Posted December 14, 2018 Author Share Posted December 14, 2018 On 12/8/2018 at 5:51 PM, Pumpkinhead said: If you want to see some really glorious stuff I would recommend checking out the ROM's website. Thecosmilia's picture is actually Opabinia, which will appear similarly jumbled as both Anomalocaris and Opabinia have non mineralized skeletons and were deposited rapidly in the case of the Burgess Shale. Considering the poor durability of the original animals these specimens are really quite beautiful and exquisitely preserved Were they actually non-mineralized? I knew anomalocaris' body was supposed to be soft, but I thought they had hard, armored, or at least calcified "fins" and heads(including the mouth and appendages). As for opabinia, I don't really know as much about, but thought that at least the body was structured similarly to anomalocaris'. It looks like its from one of those kids books or toys where you can swap different animals' heads and bodies with each other's. Anomalocaris body with kids drawing of imaginary animals' head! Link to comment Share on other sites More sharing options...
Johannes Posted December 14, 2018 Share Posted December 14, 2018 The mineralization of those early arthropods is still under debate. Quite sure is a kind of phosphate cuticula ("soft body" in the meaning that phosphate cuticulae can, under oxigenated conditions be easier decomposed by microorganisms than calcified ones). problem is, that mineralization of these animals is everytime at least secondary, even for the phosphated ones (following more critical scientist working with Chengjiang and Burgess, in whose arguments I agree). So; in my opinion they were "mineralized" in terms of a +- hardened cuticula of organophosphates, which could be "hardened" by inlays of calcite and other minerals in the molecular network of the phosphates (hard to prove with the material we know). There were some debates about the topic applied to early trilobites in the literature (but I believe somebody else here is faster than me to cite the relevant papers.. ) 2 Link to comment Share on other sites More sharing options...
Pumpkinhead Posted December 14, 2018 Share Posted December 14, 2018 As Johannes said, it is hard to extrapolate what the mineralogy of the original cuticle was as the preservation of the fossils consists of secondary mineralization. And of course some parts are hard such as the radial moutparts and the appendages. I generally see anomalocaris proper described as non-mineralized; clearly this is a generalization of the entire carapace if it is in fact correct to call it non-mineralized in the strictest sense. While a bit old, this paper does give a very brief synopsis of anomalocaridid scleritization: https://www.tandfonline.com/doi/pdf/10.1080/11250009809386724 I'm not sure how representative this is of the current whatever consensus can be found nowadays but it does give a good sense of the diversity of anomalocaridid scleritization that can be observed. At any rate, they are certainly "squishier" than a trilobite, as was opabinia. Someone once told me that opabinia looks like Noo Noo off of Teletubbies: 1 Link to comment Share on other sites More sharing options...
Still_human Posted December 14, 2018 Author Share Posted December 14, 2018 2 hours ago, Pumpkinhead said: As Johannes said, it is hard to extrapolate what the mineralogy of the original cuticle was as the preservation of the fossils consists of secondary mineralization. And of course some parts are hard such as the radial moutparts and the appendages. I generally see anomalocaris proper described as non-mineralized; clearly this is a generalization of the entire carapace if it is in fact correct to call it non-mineralized in the strictest sense. While a bit old, this paper does give a very brief synopsis of anomalocaridid scleritization: https://www.tandfonline.com/doi/pdf/10.1080/11250009809386724 I'm not sure how representative this is of the current whatever consensus can be found nowadays but it does give a good sense of the diversity of anomalocaridid scleritization that can be observed. At any rate, they are certainly "squishier" than a trilobite, as was opabinia. Someone once told me that opabinia looks like Noo Noo off of Teletubbies: Hahahahaha! and thanks for the article!!! Link to comment Share on other sites More sharing options...
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