• Welcome to TONMO, the premier cephalopod interest community. Founded in 2000, we have built a large community of experts, hobbyists and enthusiasts, some of whom come together when we host our biennial conference. To join in on the fun, sign up - it's free! You can also become a Supporter for just $50/year to remove all ads and gain access to our Supporters forum. Follow us on Twitter and Facebook for more cephy goodness.

Discussing the New Papers on Fossil Cephalopods

Phil

TONMO Supporter
Supporter
Joined
Nov 19, 2002
Messages
3,033
If anyone wants to comment or discuss the New Papers on Fossil Cephalopods please do here!

As far as possible I've only included papers that can be downloaded for free in their entirety. I don't see the point of just hinting of an interesting paper and only providing an abstract; that's just annoying!

I've locked the thread itself so that we can just keep that purely to a list of interesting papers. If anyone finds an interesting paper, please just drop me a line and I'll add it.

Thanks,

Phil

:nautiloi:
 
Joined
Apr 8, 2004
Messages
602
Phil, WOW I've worn out my copy of WordWeb, so many whopping great words !
"Origin of Ammonoid Locomotion" made the best bedtime reading, I've always viewed the various designs as looking extremely unstable & awkward but how can you compare a piece of rock to the original creature ?
Manouverability & speed through the water would dictate feeding behaviour just as the available prey dictates the form of the predator, chicken & egg ? Is there any video of a nautilus in action ?
With drag a major factor with motion thro' water I wonder what was the plan with ammonites sporting protuberances such as those from your neck of the mud.
Statoliths are another eye opener :cyclops: , I marvel at some of the instruments evolution has equipped us with to get us thro' the day but we have many millions of years over these guys but still they were equipped with equally cunning gadgets - hats off to Mother Nature & I doff my cyber cap to you for supplying this top info ! :thumbsup:
If I had loads of spare cash I treat you to a phat fossil off Ebay ! :wink:
 

Phil

TONMO Supporter
Supporter
Joined
Nov 19, 2002
Messages
3,033
Hi Spartacus, apologies for the tardy reply.....Yeah, some of those articles are classics; I tried reading the Germanonautilus one but it gave me a headache...and that was just the abstract! :smile: Well, even if some of us mere mortals don't understand these articles completely I thought it might be a useful resource for some readers. Actually, some of them are comprehensible to the non-scientist; Trachyteuthis reads fine, and Neale Monks' heteromorph paper at the end is interesting.

spartacus said:
With drag a major factor with motion thro' water I wonder what was the plan with ammonites sporting protuberances such as those from your neck of the mud.
Well, I've had a quick research for you; some Cretaceous ammonites were highly ornamented; as you say this would have increased the drag on the swimming animal. However many of these bumps are defensive trade-offs as they are bases of spines. Some of the Albian Hoplitaceae were very spiny indeed; have a look at the photo of the specimen of Euhoplites armatus in the 'Folkestone' article for example. Unfortunately I only put in a side view but the ammonite is very bulky when seen in cross section. These spine bases run in two lines in parallel rows along the specimen, the living animal would have been a ball of spines; not an image one traditionally associates with ammonites, but an appealing one. Not only would the animal have looked like a floating hedgehog and been unpalatable to predators, but the spines would have made the animal appear larger, perhaps another deterrent to potential predators.

In his book 'Ammonites' Neale Monks notes that spines are not uncommon in (the rare) Triassic ammonites but became increasingly widespead and well developed through the Jurassic and into the Cretaceous. The spines were normally hollow, which meant that they were initially full of gas, the snapping off of a spine would have led to a loss of bouyancy in the animal via the gas escaping. For this reason as the animal grew the spines were sealed off at the base after they were formed, the bumps we find on the surface of some of these ammonites are really the sealed off stumps of the spine bases; many researchers refer to them as tubercles.

Odd that the nautiloids never really developed this feature....hmm....

If I had loads of spare cash I treat you to a phat fossil off Ebay ! :wink:
Aw, thanks!
 
Joined
Apr 8, 2004
Messages
602
Hi Phil, there's no rush ! :roll:
I didn't realise that the papers had been breeeding, so I've scanned the Heteromorph paper which also is tentacularlytastic :biggrin2:
There still appears to be a great deal of debate & supposition surrounding
cephkind whether in the fossil record or existing species which is what helps to make them so fascinating.
Academically, Sir Steve O'Shea MBE OBE DFC is our leading light in terms of 21st century squidness & Neale Monks is a (if not "the") main fossil ceph player & between them I'm sure they'd be happy to admit we know a fraction of what there is to know about our fave subject.

From an engineering background & believing strongly in the "if it looks right...." approach & chaos theory joined with my new found knowledge of spiny ammonites coupled with 2 papers on ammonite locomotion I'd say we're dealing mainly with creatures that crawled about the sea bed, bobbed & swam freely about midwater & possibly did the same but on the surface.
Some couldn't swim, some could but badly, others could well.
(check out Markoceras Spitzerii)
Some looked up, some looked down, some predominantly looked up but could also look down & vice versa, others were clever dicks picking & choosing in which direction they looked at leisure.
Some were active predators, others scavengers & some nibbled a bit & had allotments.
I'd even bet my dinner money that some had feathers !

This is pure conjecture & should be read with an open mind but I believe that our nautiloid chums chose to remain unadorned purely not to look daft.

I'm glad I'm not (yet anyway) into trilobites coz I reckon I'd end up going
MAAAAAAAAAAAAAAAAAAAAAAAAAAAAD sir !!

p.s. Sorry about protuberances :oops: tubercles it is.
 

Architeuthoceras

Architeuthis
Staff member
Moderator
Joined
Nov 19, 2002
Messages
2,441

A spiny Permian nautiloid, Cooperoceras, on the right, looks like it fits on the sea floor. The smooth shelled ammonoid, left, looks like it should be higher in the water column, and going alot faster.

from the palaeos site
 
Joined
Apr 8, 2004
Messages
602
Kevin, I rest my case !
I don't know how you guys do it but WOW :notworth:
gadzooks ! you even sourced a Permian photo (if you really really want to impress tell me it's a video still).
I think you'll find the ammonoid you mention is in comm.s mode shortly to resume high speed, high altitude reconn. according to the radio transmission recording I found on Ebay.
 

cthulhu77

TONMO Supporter
Registered
Joined
Mar 15, 2003
Messages
6,638
somewhat off subject...and perhaps already known, but...
I found a great book on the sale table at Barnes and Noble last week...published in 2000, by Deborah Cadbury, called Terrible Lizard...all about the first fossil hunters...quite fascinating !
If you haven't read it, I highly recommend it !
 
Joined
Apr 8, 2004
Messages
602
G'day Greg, thanks for the tip & will add it to list . Well rated all round apart from Mr Picky of Sodding Chipbury :x
On similar vein, caught prog on National Geog on the 2 psychos engaged in all out war ripping up dinos early last century (Mantell & Owen peut etre ?). They even agreed (unless I'm seriously confused) that on death each would have his brain removed & weighed to find who had the greater intellect, once & for all. Needles to say, he who croaked last didn't play ball & the other guys grey matter resides in a jar ! what a perlum :roll:
I enjoyed it anyway :biggrin2:
 

Phil

TONMO Supporter
Supporter
Joined
Nov 19, 2002
Messages
3,033
Thanks Greg, didn't know about "Terrible Lizards". Is this a different book to her previous one "Dinosaur Hunters", or is it the USA name for the same work? I'm a bit confused as that also dealt in the rivalry between Gideon Mantell and Richard Owen unless she has written two books on the same subject? There was a very interesting docu-drama about it over here a year last Christmas; Owen was very much cast as the arrogant career-obsessed bad guy who set out to destroy poor Mantell. Mantells twisted spine was horrific stuff!

The rivalry between Cope and Marsh could make a good drama too I'd imagine. As you say though, Spartacus, it does take a lot to please Mr Picky of Sodding Chipbury.
 

Forum statistics

Threads
20,833
Messages
206,714
Members
8,457
Latest member
DaneMom6800

Monty Awards

TONMOCON IV (2011): Terri
TONMOCON V (2013): Jean
TONMOCON VI (2015): Taollan
TONMOCON VII (2018): ekocak


Top