Jump to content

Shellseeker

Recommended Posts

Hunting yesterday,  found an area of slightly larger teeth....It is not often that one location can yield Hemipristis, Mako, Megalodon and Great White.

In the Peace River, GWs are really difficult to find  and I am not positive about this one.

IMG_8581.thumb.JPG.b2fc9aa88c1e925dabdc05db6308d6dd.JPG

 

Is this a GW or a Meg...?

IMG_8580.thumb.JPG.40e5c0386bf3e196cf76b2d8b8657eec.JPGIMG_8567.thumb.JPG.a31094361fa551d12bbb0e8b465c2238.JPG

It sort of depends on whether you see a bourlette (or not) and how you see the symmetry of the serrations.

SEM-photographs-of-tooth-serrations-in-five-species-A-C-auriculatus-B-C.png.16d52c5782a2aac3ccd49efc84954676.png

 

There were a variety of Tiger (Aduncus, Contortous, Mayumbensis, and Cuvier), but no sand tigers.. Lots of Hemipristis and larger Lemons

Also a camel_llama tooth...some Armadillo scutes, and two almost identical Capybara front teeth....

IMG_5636CapybaraCrop.thumb.jpg.b9473852332c46983090b59cc4a8dbf5.jpg

 

Digging next to me, my friend found this bone,  and tossed it on the bank. I retrieved it thinking I might be able  to get it identified.. The broken half bone is 2 x 2 x 3 and a possible carpal/tarpal,  astragulas, calcaneum, etc of a megafauna like Rhino, Sloth, Bison, Proboscidien. A limited set of non_long bones.  I think Daniel @Meganeuratracked down a Rhino Astragalus this way,  and I also have the possibility that a TFF member may just recognize this 1st photo...

 

IMG_8564.thumb.JPG.fb50abe399a677d03a05fb6be3434f19.JPGIMG_8563.thumb.JPG.2005c8e80b90820c5621298437392fd1.JPGIMG_8562.thumb.JPG.1b9d08900792bacf46df4ca6aafa74de.JPGIMG_8561.thumb.JPG.3a41bd48bb19b5cbb35d64e48dcc1730.JPGIMG_8560.thumb.JPG.9cec5b3fd6a96aca6cc46f777c270f50.JPG

  • Enjoyed 7

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

3 minutes ago, Shellseeker said:

Hunting yesterday,  found an area of slightly larger teeth....It is not often that one location can yield Hemipristis, Mako, Megalodon and Great White.

In the Peace River, GWs are really difficult to find  and I am not positive about this one.

IMG_8581.thumb.JPG.b2fc9aa88c1e925dabdc05db6308d6dd.JPG

 

Is this a GW or a Meg...?

IMG_8580.thumb.JPG.40e5c0386bf3e196cf76b2d8b8657eec.JPGIMG_8567.thumb.JPG.a31094361fa551d12bbb0e8b465c2238.JPG

It sort of depends on whether you see a bourlette (or not) and how you see the symmetry of the serrations. 1.37 MB · 0 downloads

SEM-photographs-of-tooth-serrations-in-five-species-A-C-auriculatus-B-C.png.16d52c5782a2aac3ccd49efc84954676.png

 

There were a variety of Tiger (Aduncus, Contortous, Mayumbensis, and Cuvier), but no sand tigers.. Lots of Hemipristis and larger Lemons

Also a camel_llama tooth...some Armadillo scutes, and two almost identical Capybara front teeth....

IMG_5636CapybaraCrop.thumb.jpg.b9473852332c46983090b59cc4a8dbf5.jpg

 

Digging next to me, my friend found this bone,  and tossed it on the bank. I retrieved it thinking I might be able  to get it identified.. The broken half bone is 2 x 2 x 3 and a possible carpal/tarpal,  astragulas, calcaneum, etc of a megafauna like Rhino, Sloth, Bison, Proboscidien. A limited set of non_long bones.  I think Daniel @Meganeuratracked down a Rhino Astragalus this way,  and I also have the possibility that a TFF member may just recognize this 1st photo...

 

IMG_8564.thumb.JPG.fb50abe399a677d03a05fb6be3434f19.JPGIMG_8563.thumb.JPG.2005c8e80b90820c5621298437392fd1.JPGIMG_8562.thumb.JPG.1b9d08900792bacf46df4ca6aafa74de.JPGIMG_8561.thumb.JPG.3a41bd48bb19b5cbb35d64e48dcc1730.JPGIMG_8560.thumb.JPG.9cec5b3fd6a96aca6cc46f777c270f50.JPG

Thanks for sharing,

 

It always amazes me how these rivers in the USA can be dived and sieved etc for fossil goodies. 
 

That figure comparing serrations is really useful. Is that from Elasmo? 
 

I thought I would go for a little Meg on that tooth, it’s a tricky one though, missing most of the root, and a half convincing bourlette. Always nice to find something that gets you pondering though! If they were all east IDs it wouldn’t be as fun. 
 

 

Link to comment
Share on other sites

22 minutes ago, Doctor Mud said:

Thanks for sharing,

 

It always amazes me how these rivers in the USA can be dived and sieved etc for fossil goodies. 
 

The rivers are like a washing machine.  The hard stuff like rocks and fossils are extracted from the mud/sand of the land,  and deposited on the river bed in heavy concentrations,  Like the Grand Canyon the rivers dig deep trenches between high banks,  uncovering layers going back in time.

22 minutes ago, Doctor Mud said:

That figure comparing serrations is really useful. Is that from Elasmo? 
 

Tracing the Ancestry of the Great White Shark, Carcharodon carcharias, Using Morphometric Analyses of Fossil Teeth

Kevin G. Nyberg, Charles N. Ciampaglio and Gregory A. Wray
Journal of Vertebrate Paleontology
Vol. 26, No. 4 (Dec. 11, 2006), pp. 806-814 (9 pages)
Published By: Taylor & Francis, Ltd.

 

I thought I would go for a little Meg on that tooth, it’s a tricky one though, missing most of the root, and a half convincing bourlette. Always nice to find something that gets you pondering though! If they were all easy IDs it wouldn’t be as fun. 
 

Yes, most of the ones that have their roots are much easier to ID

2017May23rdGreatWhite.thumb.jpg.b6f15b9e2905400336c3207022e6f54f.jpg

Thanks for posting,  I enjoy the discussion... Jack

 

 

  • Thank You 1

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

Hmm, based on serrations, I would have said GW, but it looks like a bourlette to me.  I'll be interested to see what the experts say.

  • I Agree 1

Fin Lover

 

image.png.e69a5608098eeb4cd7d1fc5feb4dad1e.png image.png.e6c66193c1b85b1b775526eb958f72df.png

image.png.7cefa5ccc279142681efa4b7984dc6cb.png

My favorite things about fossil hunting: getting out of my own head, getting into nature and, if I’m lucky, finding some cool souvenirs.

 

Link to comment
Share on other sites

Serration size on the tooth says GW to me, but serration shape and uniformness says Meg - that’s an interesting one. @Al Dente @hemipristis @MarcoSr whatcha think? 

Edited by Meganeura
  • I Agree 1

Fossils? I dig it. :meg:

 

Link to comment
Share on other sites

Well, if that isn't a straddle-the-line tooth!

 

The size and apparent thinness of the root (what's left) of it certainly are consistent with a GW. The relatively coarse serrations would be further evidence for a GW proclamation but then there is that apparent bourlette that turns everything on its head and suggests this to be a small meg. I'm going to have to forward this photo to my meg specialist and see what his take is on it. I do love a good mystery--there is usually a teachable moment hidden within such mysteries. :)

 

The mystery bone that you salvaged from your buddy's discards does seem to have prominent articular facets that remind me of the non-moving bones further up from the carpals/tarsals in the wrist/ankle of a large mammal. To someone familiar with such bones (e.g. Richard Hulbert) they'd be able to proffer a decent ID in mere moments. Here it will take someone who has had experience in a similar bone to be able to narrow things down. Great job rescuing this from the spoil pile. ;)

 

 

Cheers.

 

-Ken

  • I found this Informative 1
  • Enjoyed 1
Link to comment
Share on other sites

2 hours ago, Meganeura said:

Serration size on the tooth says GW to me, but serration shape and uniformness says Meg - that’s an interesting one. @Al Dente @hemipristis @MarcoSr whatcha think? 

 

1 hour ago, Al Dente said:

 

I think it is a meg based on the bourlette.

 

23 minutes ago, digit said:

Well, if that isn't a straddle-the-line tooth!

 

The size and apparent thinness of the root (what's left) of it certainly are consistent with a GW. The relatively coarse serrations would be further evidence for a GW proclamation but then there is that apparent bourlette that turns everything on its head and suggests this to be a small meg. I'm going to have to forward this photo to my meg specialist and see what his take is on it. I do love a good mystery--there is usually a teachable moment hidden within such mysteries. :)

 

The mystery bone that you salvaged from your buddy's discards does seem to have prominent articular facets that remind me of the non-moving bones further up from the carpals/tarsals in the wrist/ankle of a large mammal. To someone familiar with such bones (e.g. Richard Hulbert) they'd be able to proffer a decent ID in mere moments. Here it will take someone who has had experience in a similar bone to be able to narrow things down. Great job rescuing this from the spoil pile. ;)

 

 

Cheers.

 

-Ken

 

This is a tough one because of the serrations as Meganeura points out, the thinness of the root as Ken points out, and the bourlette that Eric points out.  I've seen very thin bourlettes on a few great whites before but never a bourlette this thick and pronounced.  So I'm in the meg camp.  However the serrations in the area circled in the picture, do look like great white serrations, large, pointy and irregular.

 

 

tooth.thumb.jpeg.5b592d7f1e11e4a8979a4afff9e5cdee.jpeg

 

 

Marco sr.

  • I found this Informative 1

"Any day that you can fossil hunt is a great day."

My family fossil website     Some Of My Shark, Ray, Fish And Other Micros     My Extant Shark Jaw Collection

image.png.9a941d70fb26446297dbc9dae7bae7ed.png image.png.41c8380882dac648c6131b5bc1377249.png

Link to comment
Share on other sites

38 minutes ago, MarcoSr said:

 

 

 

This is a tough one because of the serrations as Meganeura points out, the thinness of the root as Ken points out, and the bourlette that Eric points out.  I've seen very thin bourlettes on a few great whites before but never a bourlette this thick and pronounced.  So I'm in the meg camp.  However the serrations in the area circled in the picture, do look like great white serrations, large, pointy and irregular.

 

 

tooth.thumb.jpeg.5b592d7f1e11e4a8979a4afff9e5cdee.jpeg

 

 

Marco sr.

Just as another point - I had found a similarly confusing tooth a couple months ago that everyone here agreed was GW despite the bourlette. Now, the bourlette on mine wasn't quite as pronounced, but it was definitely pretty prominent/visible!

Personally I think it's a GW despite the bourlette.

 

Edited by Meganeura
  • I found this Informative 1

Fossils? I dig it. :meg:

 

Link to comment
Share on other sites

2 hours ago, MarcoSr said:

 

 

 

This is a tough one because of the serrations as Meganeura points out, the thinness of the root as Ken points out, and the bourlette that Eric points out.  I've seen very thin bourlettes on a few great whites before but never a bourlette this thick and pronounced.  So I'm in the meg camp.  However the serrations in the area circled in the picture, do look like great white serrations, large, pointy and irregular.

 

 

tooth.thumb.jpeg.5b592d7f1e11e4a8979a4afff9e5cdee.jpeg

Marco sr.

Thanks for your response and summary... The tooth 29 mm on the slant, was laying labial side up and I immediately wondered if it was a GW.  My friend, with twice the river experience, looked at it for a long time and said GW...  It is harder to make out the bourlette at the river. The camera makes it clearer and bigger.  I left the river thinking GW, but now believe it is a Meg..

I know we have transitional cusps Chub to Juvenile Meg,  and transitional serrations Meg to Mako.  Maybe we have transitional bourlettes Meg to juvenile GWs...:shakehead:

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

3 hours ago, digit said:

Well, if that isn't a straddle-the-line tooth!

 

The size and apparent thinness of the root (what's left) of it certainly are consistent with a GW. The relatively coarse serrations would be further evidence for a GW proclamation but then there is that apparent bourlette that turns everything on its head and suggests this to be a small meg. I'm going to have to forward this photo to my meg specialist and see what his take is on it. I do love a good mystery--there is usually a teachable moment hidden within such mysteries. :)

 

The mystery bone that you salvaged from your buddy's discards does seem to have prominent articular facets that remind me of the non-moving bones further up from the carpals/tarsals in the wrist/ankle of a large mammal. To someone familiar with such bones (e.g. Richard Hulbert) they'd be able to proffer a decent ID in mere moments. Here it will take someone who has had experience in a similar bone to be able to narrow things down. Great job rescuing this from the spoil pile. ;)

Cheers. -Ken

Thanks , Ken..

Both of your comments are illuminating. 

 

On the bone, I almost left it... It was late in the day, time to leave. Those facets were staring back at me ..

This a Dolphin humerus from March of 2018..

IMG_1068.jpg.26ddadd61bde43d6af1af9f93a7a41fb.jpg

Then I thought , it might be the phalanx or metapodial of one of those big guys.mastodon_bones.thumb.jpg.7be2b0a4a6c52b0d2e96f4cf30906a1f.jpg

I would say I only have a 40% chance of ID...  With Richard Hulbert around,  I would bump that to 80%

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

My megalodon resource replied back that the presence of the small bourlette and the uniformity of the serrations make this a small megalodon for him.

 

 

Cheers.

 

-Ken

  • I found this Informative 2
  • Thank You 1
Link to comment
Share on other sites

On 2/7/2023 at 5:38 AM, Meganeura said:

Serration size on the tooth says GW to me, but serration shape and uniformness says Meg - that’s an interesting one. @Al Dente @hemipristis @MarcoSr whatcha think? 

A bit late to the party...

 

Can't disagree with any of the observations.  If. pressed, I'd vote for a meg.  A very curious tooth

  • Enjoyed 1
  • I Agree 1

'Those who cannot remember the past are condemned to repeat it.'

George Santayana

Link to comment
Share on other sites

I guess my take is that the evidence for GW vs Meg are pretty much in balance, and we have other examples of Megs with irregular serrations and small roots and GWs with small bourlettes. In a Bayesian framework, if the data are ambivalent, go with your priors, so I'd bias my beliefs toward whichever species is more commonly found at your site.

 

On the other hand, a pure parsimony-driven analysis might point to GW, since there seems to be more characters inconsistent with Meg (flatness of the blade, thinness of the root, pointness and irregularity of the serrations) than inconsistent with GW (presence of a bourlette).

 

My meta-priors are slightly in favor of Bayes over parsimony.

  • Enjoyed 1
Link to comment
Share on other sites

The best thing about a "mystery" find like this is the discussion that it generates here on the forum. A meg that looks like a meg or a GW with no ambivalent features are quite pretty to look at but there is no chance for learning and an elaboration of the features that distinguish each taxon. Just like megs with atavistic side cusps, fossils that don't fit comfortably within their pigeonholes are a pleasure to see featured here. :)

 

 

Cheers.

 

-Ken

  • I Agree 4
Link to comment
Share on other sites

I think I am a little late to the discussion but I would have to side with meg. The bourlette is just a little to thick for what I know as a GW but I am no expert.

 

- Parker

Link to comment
Share on other sites

12 hours ago, debivort said:

I guess my take is that the evidence for GW vs Meg are pretty much in balance, and we have other examples of Megs with irregular serrations and small roots and GWs with small bourlettes. In a Bayesian framework, if the data are ambivalent, go with your priors, so I'd bias my beliefs toward whichever species is more commonly found at your site.

 

On the other hand, a pure parsimony-driven analysis might point to GW, since there seems to be more characters inconsistent with Meg (flatness of the blade, thinness of the root, pointness and irregularity of the serrations) than inconsistent with GW (presence of a bourlette).

 

My meta-priors are slightly in favor of Bayes over parsimony.

It is always difficult even with my own experiences over 15 years of fossil addiction in the Peace River.

I know that I have found exactly 5 Great Whites. During the same period, I would estimate no more than 100 Megs a year and so the ratio is likely about 250 to 1.  

  • I found this Informative 1

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

Just now, Shellseeker said:

It is always difficult even with my own experiences over 15 years of fossil addiction in the Peace River.

I know that I have found exactly 5 Great Whites. During the same period, I would estimate no more than 100 Megs a year and so the ratio is likely about 250 to 1.  

It took me a while to get on TFF since I posted 2 days ago... For the first time in a long time , I did back to back hunting trips,  and tonight my back is very painful... But I thought I would share this find from yesterday...

Sometimes I imagine that if I just talked a lot about a species, that species fossil will magically show up.

This tooth is 45 mm on the slant. It has been a (long) while since I found my last GW.

IMG_8593crop.JPG.bc85b4db7f203ff7c94fe177d6806b94.JPG

  • Enjoyed 5

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

4 hours ago, JBkansas said:

That's a beautiful tooth. I wonder what causes that pattern on the enamel.

I’ve always heard it (And this is probably wrong, but anyway) that it’s due to roots pressed up against the tooth as it fossilizes

  • Enjoyed 1

Fossils? I dig it. :meg:

 

Link to comment
Share on other sites

Great tooth Jack.  Let us know what fossil you are thinking about prior to your next trip out, so we can look forward to an exciting trip report. Haha

 

And I was in the GW camp for the first tooth, but the knowledge and expertise of all those supplying comments convinced me that meg was a better choice.

  • Enjoyed 1
Link to comment
Share on other sites

I don't believe serration size or shape are very good characteristics to use when identifying shark teeth, there is so much variation between individuals. I think I've posted these photos before. The first two photos show two Otodus auriculatus from the Castle Hayne Formation that show very different serrations. The last photo shows two Carcharodon teeth from the Rushmere Member of the Yorktown Formation.

 

auricpair.thumb.JPG.2de8a59cf64b6b5bdeb511da4bde9e7b.JPGauricpair3.JPG.3190fe8aa14dc3649f876388a19102e3.JPG

 

 

carcharodon pair.jpg

Link to comment
Share on other sites

4 hours ago, Meganeura said:

I’ve always heard it (And this is probably wrong, but anyway) that it’s due to roots pressed up against the tooth as it fossilizes

Either while it is being mineralized or after such a process. Roots (and the symbiotic mycorrhizal fungi) are really quite efficient at seeking out minerals needed for the growth of the plant. Calcium and to a larger extent phosphorous are essential minerals needed for plant growth--much of the phosphate mined from the phosphate region of Florida goes to plant fertilizers.

 

A shark tooth would have been deposited in the sandy matrix in a marine environment and so plant roots would have had very limited access to the tooth as it was becoming fossilized. The "lightning strike" patterns on the enamel of fossilized shark teeth are more usually due to exploring root tendrils that have found the tooth (and its cache of phosphorous) long after the tooth was mineralized.

 

Terrestrial fossils could well have been tapped for their mineral stores long before the bones were fully mineralized given their accessibility on land and proximity to growing plants. It is likely (even probable) that other bones beyond teeth are having their phosphorous leached away by plant roots but you don't often see the dendritic patterns on the bone surface. The shiny smooth enamel surface makes a much better backdrop for the signs of the root's efforts to be seen.

 

Once you know the common term used for this phenomenon is "lightning strike" it is possible to find lots more examples of this process:

 

https://www.google.com/search?q=fossil+teeth+lightning+strike&tbm=isch

 

 

Cheers.

 

-Ken

 

  • I found this Informative 4
Link to comment
Share on other sites

46 minutes ago, digit said:

Either while it is being mineralized or after such a process. Roots (and the symbiotic mycorrhizal fungi) are really quite efficient at seeking out minerals needed for the growth of the plant. Calcium and to a larger extent phosphorous are essential minerals needed for plant growth--much of the phosphate mined from the phosphate region of Florida goes to plant fertilizers.

 

A shark tooth would have been deposited in the sandy matrix in a marine environment and so plant roots would have had very limited access to the tooth as it was becoming fossilized. The "lightning strike" patterns on the enamel of fossilized shark teeth are more usually due to exploring root tendrils that have found the tooth (and its cache of phosphorous) long after the tooth was mineralized.

 

Terrestrial fossils could well have been tapped for their mineral stores long before the bones were fully mineralized given their accessibility on land and proximity to growing plants. It is likely (even probable) that other bones beyond teeth are having their phosphorous leached away by plant roots but you don't often see the dendritic patterns on the bone surface. The shiny smooth enamel surface makes a much better backdrop for the signs of the root's efforts to be seen.

 

Once you know the common term used for this phenomenon is "lightning strike" it is possible to find lots more examples of this process:

 

https://www.google.com/search?q=fossil+teeth+lightning+strike&tbm=isch

Cheers. -Ken

 

:tiphat:You are one of many plus unique in your detailed knowledge combined with the ability to craft the words that enhance understanding in those of us that do not have that knowledge.   :default_clap2::default_clap2:.  Adding value to the TFF forum

  • I Agree 1

The White Queen  ".... in her youth she could believe "six impossible things before breakfast"

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...