A Mysterious Ammonite.

[Steve O'Shea]

This thread reminded me of a dream I had several months ago - I was looking at freshwater squid in a crystal-clear jungle stream. The squid really looked weird, but they were definitely squid.

Maybe this was a premonition.......

 

[Fujisawas Sake]

Dreaming of cephs?

Any thoughts, Steve? I mean freshwater and all? Are there any species that handle brackish water?

Sushi and Sake,

John

 

[Architeuthoceras]

Not alot of detail in the following reference, but it does infer that they are rethinking ammonoid habitat and including superhaline, subhaline, and even brackish (surface) water environments. Still not fresh, but ammonoids could have been headed up stream until their demise at the end of the Cretaceous.

This book is a must read for anyone interested in ammonoids. It is a costly book, but can be found in most university or larger public libraries. I think I have plugged this book before here on Tonmo, which only shows what an indispensable reference it is.

Also, I have been dreaming of Cephs since I was 16

(Reference)
Westermann G.E.G., 1996. Ammonoid Life and Habitat. IN Landman, Neil H., Kazushige Tanabe, and Richard Arnold Davis, editors. Ammonoid paleobiology. Plenum Press, New York [ISBN: 0-306-45222-7]

 

[Clem]

Hello Phil,

Your overview of Ammonites is excellent. I hadn't known anything about them prior to finding TONMO, and found the posts on the subject to be largely impenetrable (due to my ignorance). Thanks for so ably orienting this novice.

One question inpsired by your text: have ammonite fossils been scanned with CAT/MRI technologies? (There have been some recent, succesful ID's of fossilized soft structures in dinos using these methods.) Has it been tried with fossil cephs?

Clem

 

[Phil]

Hi Clem,

Thanks very much, by the way.

Funnily enough when I was having a scout around for information on ammonite biology on the net the other day I came across a very interesting reference. Unfortunately I cannot find any further details than this and no images that I can link to, but for what it is worth........

At the 1999 Palaeontological Association meeting in Edinborough, three researchers from the UK presented some fascinating images of an ammonite that displayed some of the soft bodied parts still in situ preserved in calcite in the body chamber, this is the first time this has ever been announced. All I can tell you is the ammonite was the Jurassic Sigaloceras and was scanned with CT imaging, X-Ray, UV, SEM and EDAX (whatever that is). Apparantly results were obtained showing the digestive system, muscles and siphuncle. The researchers reconstructed the functional morphology of the ammonite.

Unfortunately, this does not yet seem to have been published, or if it has, it is in the realms of academia and will not filter down to us mortals for years!

 

[Clem]

Phil,

Aha, thank you. I'll join in the hunt for that data. Stuff that good shouldn't be kept under a bushel.

Perhaps you could take your mystery ammonite to hospital, introduce him as your "very ill" pet snake, and demand the full battery of imaging scans. Act very distraught.

Yours truly,

Clem

 

[Phil]

Ha ha!

Actually my sister is a doctor of radiography. I never thought of asking her.....I'll see what I can do.

Quincy: "Gentlemen, welcome to the world of forensic palaeontology...."

 

[Fujisawas Sake]

Quincy: "Gentlemen, welcome to the world of forensic palaeontology...."

Watch a bunch of malcaologists faint, I take it?

I still think there may be more to the idea of freshwater colonization, or lack thereof... Only time will tell...

Sushi and Plum Wine

John

 

[The Moog]

Hello, Phil's "doctor of radiography" sister here, I'm really only used to people and bits of studff made to look like people, but I know the science, and CT would be the thing I imagine, you can scan in slices and reconstruct (just like they do with mummies to see what's in them). I imagine MRI may be a problem if there's any trace of metal that will go magnet-mad.
As I exist in academic-land, keepers of secret documents, I'll see if I can find the article. We currently do archaelogical stuff here, x-raying fossils is the next step? Joint research anyone?

 

[Phil]

Hmmmm......CT could be a problem. Most of the ammonites I have found were preserved in iron pyrites so I suppose they could not be scanned. I have a couple in chalk, but I doubt if you would get any good results in that either.

I'll see if I have any others preserved in other rock-types.

Could be fun.....images posted here first.......

 

[Steve O'Shea]

Hello, Phil's "doctor of radiography" sister here ....... Joint research anyone?

LOL. I did a few CT's of giant squid (Architeuthis) several years ago (I have a cobber that is also a radiologist) - in fact they nearly had to be vacate a floor of the hospital because of the smell.... . We are planning to do this again on a different kind of squid (Moroteuthis) in ~ 5 weeks, and scan a few recently received ammonites (Rhaeboceras) with aptychus and radular teeth in situ. I think our problem is one of getting the images into some electronic format that we can post online. Any suggestions Moog?

The CT's of Architeuthis were rather interesting; it was very nice to observe in situ the two tiny 'bones' (statoliths) in the ventral surface of the cartilaginous cranium (they're only 2mm in greatest dimension - I was surprised at the resolution of this equipment). At the time I was looking for additional calcareous structures in the squid that might be of value for aging or systematic purposes. The lenses were calcareous - surprising to me then, but I've since learnt this to be true of squid. However, other than the lenses and the statoliths, and a few irregularly distributed small bodies/deposits of carbonate throughout the cranium, no other deposits were found.

What we did find, and did not expect, were 3 very clearly defined cartilaginous zones/bands/layers in the cranium - different densities of cartilage I think Mike (my cobber) said. Hard to know what these represent, but the immediate thought was that they represented three distinct growth stages (we do tend to jump to conclusions - but the change was so abrupt). I guess it means something and that we'll just have to work harder to figure out what it is. I suppose one way of looking at this would be to get squid of a known age and see whether there's any corelation between their age and different densities of cartilage. More study needed!

There was something in the CT's that excited Mike that he thought might have some medical application .... but for the life of me I do not recall (I think it had something to do with the eyes).

The Moog - joint research! Interesting proposition!!

Looking forward to some images online
Cheers
Steve

 

[Clem]

Phil & Moog,

In addition to the 2000 PALASS abstract which described the [i[Sigaloceras[/i] scans, there was a 1999 PALASS conference abstract that announced the discovery of the fossil (but made no mention of the non-invasive investigation that would follow). It says a little more about the formation in which it was found. Maybe that would help to identify fossils that would be amenable to scanning?

See "Ghosts of Ammonites Past," here:

http://www.palass.org/pages/archive/confabs99.html



Clem

 

[The Moog]

Steve said...
"I think our problem is one of getting the images into some electronic format that we can post online. "

(Can't do flashy quote thing yet).

Well, if you have them in electronic format at the scanner site, they are probably DICOM images, you can donwload a DICOM reader from the internet and it will convert to .bmp or .jpg, if you only have the printed copy, you can scan them like a normal photo and post like any other picture.
Hope this helps, and I will search for a picture of Phil when I next visit our parents house.
A couple of us here are quite keen on x-raying some of Phil's fossils, tho' you'll all have to wait as I'm off to the USA to teach,in 3 days time for three months, so on my return it will be top of my list!
I will be checking posts though and learning lots more

Ali (the Moog)
[/quote]

 

[Steve O'Shea]

(Can't do flashy quote thing yet).

Me neither

I'll do the scan trick and see where that gets us; we're about to (hopefully) post an entire giant squid CT-style on TONMO; that's gotta be a near first!
Ta
O

 

[The Moog]

We have a special scanner for x-ray film, so, see how you go with a normal scanner, but if the resolution isn't up to it, ask your Radiologist friend if he knows of such a thing.
can;t wait to see the CT squid!
Ali