View Full Version : A Mysterious Ammonite.


Phil
Apr 21st, 2003, 06:46am
So there was I last night down the pub, as usual, listening to some terrible jazz, when this chap says to me: “Phil, I know you are interested in fossils. I’ve got a really large one in my shed. Do you want to see it?” Rather nervously accepting his offer, I went to his house at two in the morning, carried on drinking copious amounts of his lethal home-brewed cider and he gave me this enormous ammonite!

I got stopped by the police on the way home who asked me what on earth I was doing at half past four in the morning staggering around and carrying something gigantic and suspicious in a bag. I explained to the officer, in a half-cut sort of way, that it was a limestone ammonite of immense proportions. The officer looked somewhat perplexed and drove on, obviously thinking I was some sort of nutter.

Anyway, I have absolutely no idea what the species of ammonite actually is, and I would gratefully like to hear any suggestions. Unfortunately the person who gave it to me did not know either and did not know where it was found. All I can say is that it is preserved as limestone, came from the UK, has complex suture marks and has no keel. It is 13 inches across. I suspect it may be Jurassic, due to the lack of ornamentation, but I’m not exactly sure.

tonmo
Apr 21st, 2003, 07:18am
Wow! Nice catch. See, good things *do* happen when you drink heavily. :beer:

Why do I get the feeling that your friend is going to wake up this morning and say, "ugh, my head... hey! Where the hell is my ammonite???" :)

Architeuthoceras
Apr 21st, 2003, 09:41am
Great fossil Phil!

Sorry I can't help you with an I.D., It does look like it came from the Jurassic or Early Cretaceous.

I used to come home with pretty things like that after a good night on the town, well maybe they were a little softer, I can't remember.

:ammonite:

WhiteKiboko
Apr 21st, 2003, 11:38am
are you sure he gave it to you? :) i know a few times in the past ive gone klepto in the wee hours.... but not to worry, if you were subjected to horrible jazz all night, you can plead temporary insanity.... also, its good to see that a bottle of beer is still a well recognized unit of measurement... (as long as theyre the 12oz/355ml kind and not those little 6-7oz ones)

congrats on the interesting find...

Melissa
Apr 21st, 2003, 11:16pm
Your story is almost as good as the ammonite! :lol: You make me think I should hit the bars more often. :beer:

Melissa

Fujisawas Sake
Apr 21st, 2003, 11:45pm
"oooooooh,

A Guiness goes well
with an ammonite shell
At any time o' night

I'll wager some quid
and a big local squid
It's not a be-le-mite

O' fossil, old fossil
those secrets you keep
of muscle scars
and tissue deep
Obsession of ours,
Goodbye to sleep

A Guiness goes well
With an ammonite shell
At any time o' night..."

Okay, this doesn't answer the question, and its not QUITE a pub song, but since the topic seems to be drinking and thinking... of squid... :P

Sushi and Sake,

John

Phil
Apr 22nd, 2003, 07:42am
Thanks John, that was great! I'll copy that and show my ammonite donating aquaintance next timer I'm out. I think he will love it!

I think you should throw in a 'Heave-to, me hearties' and make it a sea shanty!

Phil
Apr 22nd, 2003, 10:15am
I think I've got it.

If anyone out there knows any better, then please shout!

I believe that this is an example of Lytoceras aaleniarum based upon a photo on page 42 of Neale Monks & Philip Palmers book. The form and the suture lines look, as far as I can tell, identical.

If I am right then this was a big and bulky Jurassic ammonite that was probably a bottom feeder. As it was so bulky and unstreamlined it would have been a poor swimmer. What is quite interesting about this fossil is that the sutures are really quite complex up until the final three or four body chambers when they rapidly become very simple, just a slight curve on the final (preserved) body chamber. This can be seen in the photo if you look closely.

I would imagine that this would imply the animal had reached a specific stage of development in its life, probably sexual maturity, and we may be looking at the whole and intact animal rather than a fragment.

Architeuthoceras
Apr 22nd, 2003, 12:07pm
Phil,
It looks to me like the last half whorl or so has been weathered, and so the more complex part of the sutures are missing. The sutures on ammonitic ammonoids are complex but as you move toward the center of the septa they become alot more simple, almost smooth in the center of the whorl. Usually as an ammonite reaches maturity it begins to slow it's growth so the sutures would become approximated (closer together). I cannot tell if the sutures on your specimen are closer because of the weathering. another indication of maturity would be a change in ornamentation or shape of the aperture, but I cannot see any ornamentation and the last whorl or body chamber is missing, this would add another 3/4 or more whorls to the conch. The complete conch would have been alot bigger.

Just the opinion of an amateur ammonitologist.

:ammonite:

Phil
Apr 23rd, 2003, 03:09am
Thanks Kevin.

I've gone back and had another look at it and I think you are absolutely right. I may have jumped the gun a bit in my post above (Still learning, you know!).

The lack of complexity on the final couple of sutures does indeed seem to be an artifact of weathering and the sutures do not become more compacted towards the (missing) aperture. It's a pity the centre is quite worn and the rear of the fossil, which you can't see in the photo, is much more eroded.

I still think it was a lucky find!

Thanks a million.

Fujisawas Sake
Apr 23rd, 2003, 03:32am
Phil,

Maybe I should compose "squid songs" to spin a much more positive image of our teuthoid buddies...

Okay, maybe not... :heee:

BUT... It was a lucky find, and I'm happy for you. Is there any way you can find out more? Any schools nearby with an "ammonitologist"? :lol:

Sushi and Sake,

John

Architeuthoceras
Apr 23rd, 2003, 10:22am
It is a great find Phil, and after looking thru Monks & Palmer it looks like your ID is on the money.

Fujisawas Sake
Apr 24th, 2003, 02:01am
Phil (or anyone),

The last question I asked in my topic "Malacology: H.G. Wells Style" was about freshwater cephs, or the lack thereof. Is there any evidence that ammonites were exclusively marine? And is there any evidence that any cephs may have tried to make it to the freshwater? Any ideas on why we don't have freshwater cephs? I mean, I can guess the physiological reasons, but not the evolutionary ones....

Sushi and Sake (And other food for thought)

John

Phil
Apr 24th, 2003, 07:56pm
As far as I know there is absolutely no evidence for freshwater ammonites. Very few molluscs at all seem to have made the transition to freshwater, and those are bivalves and gastropods.

I've had a search on this and can find no evidence, but if I can find anything to the contrary I will, of course, let you know.

Pity really, who wouldn't like a pet ceph in their village pond?

Fujisawas Sake
Apr 24th, 2003, 09:39pm
Phil,

My wife thinks it has to do with niches occupied by vertebrate predators. That might be true as well....

Steve O'Shea
Apr 25th, 2003, 01:12am
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
Apr 26th, 2003, 02:15am
Dreaming of cephs? :sleeping:

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

Sushi and Sake,

John

Architeuthoceras
Apr 28th, 2003, 01:02pm
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 :sleeping:

(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]

:ammonite:

Clem
Apr 29th, 2003, 10:20pm
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
Apr 30th, 2003, 07:10am
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
Apr 30th, 2003, 03:04pm
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
Apr 30th, 2003, 03:22pm
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
May 1st, 2003, 02:14am
Quincy: "Gentlemen, welcome to the world of forensic palaeontology...."

Watch a bunch of malcaologists faint, I take it? :heee:

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
May 14th, 2003, 02:17pm
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
May 14th, 2003, 02:22pm
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
May 14th, 2003, 03:17pm
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.... :mrgreen:. 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
May 14th, 2003, 03:20pm
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

:wink:

Clem

The Moog
May 15th, 2003, 12:04pm
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)
:bugout: [/quote]

Steve O'Shea
May 15th, 2003, 03:24pm
(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
May 16th, 2003, 12:40pm
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

Phil
Jan 18th, 2005, 08:29pm
Image restored. That incident with the Police and the ammonite still makes me chuckle. Oh dear.