Help identify

[Mahnmut]

Played a bit (cut away) with the scan from Digimorph that @JohnJ recommended.

Its similar enough to make me confident to say that we are looking at a relatively horizontal cut through someones occipital region, probably a toothed whale (with less confidence), its still quite different from the dolphin skull I used as a reference .

The cut I simulated is not exactly fitting, but my pc takes to long for these things for much try and error.

The nasal septum (or what lies behind it) looks much thicker in the fossil, I do not find a correlate for the two highly structured openings the fossil has.

It being a baleen whale or one of the earlier forms could also explain the differences, I did not find a scan with internal structures for one of these.

Hope to hear from the experts!

Best regards,

J

[pachy-pleuro-whatnot-odon]

1 hour ago, Top Trilo said:

If the red part is a fossil are you saying these parts are also part of the fossil? Because those areas aren't as symmetric.

 

1 hour ago, Fossildude19 said:

I would expect this from a broken/eroded rock/bone cross section, though.

 

1 hour ago, HuckMucus said:

That is part of the interesting thing, when looking at a cross-sectional aspect with more erosion on one side than the other.  It take more imagination than I have to visualize the "whole", especially with something so complex as a skull with nasal/sinus material.  Nevertheless, while not perfectly symmetrical, the portions you point out are nonetheless "there" on opposite sides, just at different levels.  I think.  MO. 

 

When ichthyosaurs die, they often crash nose-first into the sea floor, which crushes and breaks part of their rostrum, making any cross-section through this very difficult to interpret (haven't ever seen such a cross-section, but one can imagine how intricate it must look). Another thing to keep in mind is that we might not actually be looking at a perfectly coronal, horizontal or sagittal cross-section, meaning that the bones may look elongated on one side versus on the other.

 

Think about a block of wood taken from a tree trunk. If you slice it horizontally, you'll get a ring pattern (horizontal section); take a pizza-slice  out of the trunk cutting through it vertically, and you'll get a pattern of vertical bands (radial section); but cut through the wood just outright vertically and you'll end up with a pattern of bands and loops (tangential section). Cut a piece of wood diagonally, and the patterns you see will become even more complex. If the latter is what's going on with the presumed skull, you'll end up with unexpected patterns.

 

Wood-cutting planes (source)

 

 

1 hour ago, JohnJ said:

Try this Digimorph Bottlenose dolphin entry.  Select the coronal or horizontal slice movie.

 

Great site! Will definitely bookmark this for later! Had a bit of difficulty finding the video you referenced, hence a pointer below, but very instructional, as is the dynamic cut-away (which will also give you an impression whereabouts along the skull the cross-section shown is located. Not having an actual 3D model, as in Jan's case, available, though, is a bit limiting in that you can't analyse the potential for cross-cuts at odd angles, as explained above. Still, this was the resource I was looking for when I posted my example images before, so again: an extremely useful resource!

 

[HuckMucus]

What's intriguing to me about the matrix is that creamy looking substance appurtenant to the red "inside the hooks" which does not match *most* of the standard banding outside.  The cream also seems to be in what looks like those two "sinus" dots in the middle.  Hmmmm? 

Edited June 7, 2022 by HuckMucus
clarify

[Top Trilo]

10 minutes ago, HuckMucus said:

The cream also seems to be in what looks like those two "sinus" dots in the middle.  Hmmmm? 

Are you suggesting the creature suffered from a severe sneeze? 

[pachy-pleuro-whatnot-odon]

14 minutes ago, HuckMucus said:

What's intriguing to me about the matrix is that creamy looking substance appurtenant to the red "inside the hooks" which does not match *most* of the standard banding outside.  The cream also seems to be in what looks like those two "sinus" dots in the middle.  Hmmmm? 

 

Nah, to me this is simply sedimentary infill. Unless I'm mistaken in my geology, each of the regular bands you see in the rock represents a different depositional episode with the alternating colours pointing to differences in depositional environment (could be tidal deposition near to an estuary, lagoon or river delta where sandy sediments washed in from sea might be interchanged with more humus-rich ones carried in from land, kind of like a varve in a glacial lake deposit). Water currents would probably keep deposition during each of these episodes rather minimal. But with an open skull lying there sediment would've found an easy way in, but would've had a much harder time to get back out again. Hence, you get a thick layer of sediment on the open inside of the skull.

[JohnJ]

A couple of rotated coronal slices through a Walrus Skull on Digimorph.

 

[Mahnmut]

The second 3d-model I used is available at the same site from digomorph, directly below the animations, labelled stl.

There goes my confidence in the horizontal cut through the occipital region ^^ .

well spotted @JohnJ.

Much closer fit in orientation.

[Fossilnoodlechamp]

Wow nice find either way, this site has some very intelligent people in it.

[Auspex]

1 hour ago, JohnJ said:

A couple of rotated coronal slices through a Walrus Skull on Digimorph.

Great Freaking Googly Moogly! What a great fossil!

This thread has to be among the best we've published. Wow... Just wow!

 

[Fossildude19]

@Boesse

[Shellseeker]

I have been watching this thread.  Normally , I get similarities , vibrations, possibilities. I have to admit that I do not have clue... Will watch with interest...

[Sjfriend]

This is too cool, awesome, jaw-dropping  to be ignored. I too saw a whale skull cross section at first glance.

 

I also would recommend getting photos and location to a local paleontologist! Of course I would have also done everything in my power to get it home (just to make sure it stays safe, wink wink)

[jpc]

bobby will be along promptly (he says with great hope)

 

[SawTooth]

Fossil or not it's definitely interesting.

[Mahnmut]

Interesting or not, it is definitely fossil

 

I am deeply ashamed to have gotten the anatomy 90° wrong , but I at least am sure about that.

Very curious to hear what Boesse has to say.

Best regards,

J

[Meganeura]

Idk what on earth it is, but that screams walrus skull to me based on the cross section from @JohnJ. 

Regardless, what an incredible find!

[HuckMucus]

200 or 800 pounds, I don't know.  Only a 1/4 of it showing, I don't know.  But if we are looking at a skull and if the balance of the animal goes down into the sand, just think what else might be showing on the sides and bottom of this rock.  Time to break out the back hoe?  If not you, then some school or museum?  I hope I'm not being punked.  

[Mcmaker]

Wow, i'm astonished by your imagination and thinking process! What a case!

[abyssunder]

On 6/6/2022 at 3:43 PM, Carl said:

The symmetry is WAY to accurate for me to not believe that's a fossil. 

@Boesse

I tried to say that the symmetry is a starting point in the ID of this specimen and you see that.

[FB003]

Be sure to keep us updated! Very interesting topic.

[Carl]

On 6/7/2022 at 10:32 AM, Mahnmut said:

Hello again,

I tried looking at different 3d scans of whale skulls to find a cut that resembles this one here.

Until now all the whale scans I found are optically made, that means scanned from the outside without internal detail. I hope to find a ct scan of a dolphin that would show the internal structure. But I think the cut of an Orca skull (nmml:1850) via morphosource) shows more or less the view your fossil does. Still wondering what the finely structured areas are, maybe even inner ear structures?

The way the sediment flowed (?) around the bone is fascinating also, or, to use a technical term I just learned, jaw-dropping.

 

The section through the skull in question would most likely be transversely through the skull rather than frontal/dorsal/longitudinal evidenced by the paired turbinate-like structures,

Edited June 9, 2022 by Carl

[Carl]

I'm pretty sure that whales have a poor sense of smell and lack complex turbinates so I'm thinking of marine mammals outside of cetaceans, like pinnipeds.

[pachy-pleuro-whatnot-odon]

7 minutes ago, Carl said:

I'm pretty sure that whales have a poor sense of smell and lack complex turbinates so I'm thinking of marine mammals outside of cetaceans, like pinnipeds.

 

Seems like quite a large skull for one, though...

[Carl]

5 minutes ago, pachy-pleuro-whatnot-odon said:

 

Seems like quite a large skull for one, though...

That's a good point. Elephant seals have enormous heads, but this could be too big. Seems some cetaceans do have turbinates so I'm not entirely ruling them out.

Edited June 9, 2022 by Carl

[Mahnmut]

Carl, you are of course right concerning the orientation of the "cut", as I have acknowledged before.

When I made my dolphinskull-experiment I was so sure it would have to be a whale (because of the size) that I assumed the nasal passage to be near vertical, wondering if the turbinate structures could be cochleae. the overall shape was close enough to fool me.

JohnJ found a much better fit with the coronal section of the walrus.

I wouldnt expect turbinates in a whale either.

Best regards,

J