Burgess Shale Cephalopod

Thanks Roy!

Here is a link to a UK announcement:
Newly discovered fossil revealed as the mother of modern-day molluscs

"Our discovery allows us to push back the origin of cephalopods by at least 30 million years, to the famous Cambrian explosion about a half-billion years ago," said Jean-Bernard Caron of the Royal Ontario Museum in Toronto.

An abstract from Charles D. Walcott and the discovery of the Burgess Shale the might have additional info to interest our fossil members.
 
I'll be very VERY interested to see how this affects the whole idea of nautiloids to coleoids transition.
 
It all seems very odd to me - the thing looks so advanced, akin to a modern coleoid. What on earth is it doing so far back in time?

According to the conjectured time line available at Pharyngula it is a dead-end lineage sharing a common ancestor with the nautiloids and others in the early Cambrian. It didn't lead to the squid and ammonites at all. So where does this leave our small creeping shelled early nautiloids such as Plectronoceras?

http://scienceblogs.com/pharyngula/upload/2010/05/mother_of_all_squid/nectocaris_phylo.php

Can a syphon really be interpreted? What form did it's own ancestors take, shelled or not? Where is the radula? Isn't a dead-end lineage all to easy to place an unfamiliar animal in?

Something is not right here...
 
How sure are they that the funnel is indeed that, a funnel, and not a mouth of sorts, there's a bit too much Anomalocaris going on here, from my perspective...
 
Yeah, that looks really like a larval dinocarid/anomalocarid. (Hence 2 arms and a 'funnel' that looks very like an anomalocaris mouthplate, segmentation, and projections that look like fins along the sides) In fact, stratocladistically speaking it has very little to do with cephalopoda. None of the ancient cephs have much in common. It shares 5 times as many characters with anomalocarids as it does with cephalopods. It would be weird for it to lose the shell, then evolve a specialized shell with air chambers, then slowly lose the shell again. Not the most parsimonious solution. And the segmented body structure isn't even seen in modern cephalopods, or any molluscs, except maybe chitons, but that's mostly a hard tissue/gill pairing. It's convergent evolution only. It had a similar lifestyle to modern squids. How many months would a paleontologist have to wait before publishing a paper reclassifying it?

Here's another link with another picture of a different fossil specimen.

http://blogs.discovermagazine.com/n...tually-a-500-million-year-old-squid-relative/

You can clearly see the 'funnel'. It looks much like a mini anomalocarid mouth to me. Anomalocaris mouth below for comparison.

http://ircamera.as.arizona.edu/NatSci102/NatSci102/text/cambrian_files/burgess22.jpeg
 
Also, why no radula? We see radulichnites as far back as the pre-cambrian mollusc kimberella, and the radula's one of the easiest spotted features of pohlsepia (soft bodied octopod ancestor from Mazon Creek).
 

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