Is That Terry Dactyl' Fossil?

[Scylla]

http://news.bbc.co.uk/local/dorset/hi/people_and_places/nature/newsid_9225000/9225848.stm

Ever wonder who's been eating your ammonites?

[Terry Dactyll]

Scylla.... No its not my fossil... but between a couple of friends we tried to narrow down the predatory culprit and I think we may have got a little closer.... I will have to ask permission from my friend to post an image and theory we shared....

Edited December 1, 2010 by Terry Dactyll

[Terry Dactyll]

I got the go ahead to post the image which I hope you find as interesting as we did..... Following the BBC news release that Paddy & Chris at the Fossil Workshop in Lyme Regis had noted damage to Promiceras ammonite shells in consistently the same area on the shell, they concluded ''the ammonites were eaten by a fellow cephalopod such as a soft-bodied squid.''...

We had a follow up discussion and I suggested that very often predator and prey are found fossilised together (like meg teeth& whale bones) and I had wondered if the Cenoceas Nautilus we find all through the lower jurassic could be responsible for feeding on the small ammonites... to manipulate the shell to attack in the exactly same place takes some skill and I thought a nautilus could be tactile and intelligent enough to manage this attack at the position the sinue or muscle holds the cephlopod in the shell... hence maximising on the potential meal... I had seen a couple fossil nautilus beaks over the years and they appeared strong enough to do the job.... its only the small shells that this is noted on and potentially could have been part of the food chain for the nautilus of the day... Promiceras are thought to be possibly juvenile Xiphoceras...

Anyway... My friend followed this up by posting the image of a Promiceras he had found showing the feeding damage next to a fossil nautilus beak from the green ammonite layer..... The resemblence in the profile is uncanny..2 very nice fossils...