monty
Mar 2nd, 2007, 02:37pm
http://scienceblogs.com/pharyngula/2007/03/orthozanclus.php
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View Full Version : [News]: Pre-ceph Cambrian thingie (orthozanclus) monty Mar 2nd, 2007, 02:37pm http://scienceblogs.com/pharyngula/2007/03/orthozanclus.php octobot Mar 3rd, 2007, 06:55am Fossil Find May Be One of Oldest Ever (http://news.google.com/news/url?sa=T&ct=us/3-0&fd=R&url=http://www.associatedcontent.com/article/166059/fossil_find_may_be_one_of_oldest_ever.ht ml&cid=0&ei=JVTpRdjIMaCIsgGTorneBQ) Associated Content, CO - 7 hours ago It could be a "missing link" to the evolution of cuttlefish, squids, and octopus. The ancestors of the multi-tentacled sea creatures include ammonites, ... More... (http://news.google.com/news/url?sa=T&ct=us/3-0&fd=R&url=http://www.associatedcontent.com/article/166059/fossil_find_may_be_one_of_oldest_ever.ht ml&cid=0&ei=JVTpRdjIMaCIsgGTorneBQ) tonmo Mar 3rd, 2007, 08:04am Quite a discovery! Jean Apr 3rd, 2007, 09:00pm makes me think of a chiton..........with spines! J VaBeach Girl Apr 19th, 2007, 01:27am KEWL!!! Stephanopod Jun 13th, 2007, 09:30am So I'm a bit late (call me a born again naturalist). As interesting as facinating this seems, however it might be a tad early to see a link with cephalopods... After all, we are talking about a (most probably) blind specimen that crawled (or maybe swam...) on its belly. Where are those tentacles? Jean Jun 13th, 2007, 09:32pm So I'm a bit late (call me a born again naturalist). As interesting as facinating this seems, however it might be a tad early to see a link with cephalopods... After all, we are talking about a (most probably) blind specimen that crawled (or maybe swam...) on its belly. Where are those tentacles? True and yet there is a link between cephalopods and mussels (which are sessile) and snails/slugs (which crawl) and so on, they are all molluscs! The speculation is that this beastie might be molluscan (or annelid...........:grin: ), if molluscan, it's related to cephs albeit distantly! j willsquish Jun 15th, 2007, 07:20pm It's neat, but only a sister group at best. Keep in mind that at the same time orthozanclus was around, so was Scenella, the monoplacophoran. So, the shelled molluscan lineage was already in place, and shelled guys were where cephs come from too. When you look at kimberella, the precambrian mollusc/mollusk (British vs. American sp.) you can see it's not far from being exactly like a polyplacophore or monoplacophore. It's just not shelled yet. Attached is a nice pic of a kimberella. It's about twice the size of the original. The original is around an inch long from mouth to end. Actually the thumbnail version's about right, maybe a little small. You can see all the little gills around the edge, and a deeper spot where the thick noncalcified mantle was, with a poo trace to the right and a head end to the left. Enough traces of radula like feeding from the time makes me think it's can easily fit into mollusca. All that aside, the orthozanclus does unite a couple oddball cambrian 'explosion' beasties into something one could clearly speculate on. The tree of life is getting nearer to complete, albeit perhaps asymptotically. Graeme Jun 17th, 2007, 08:19pm That Orthozanclus reburrus thing looks very Giger-esque! Very cool :D |