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Troodon

My Jurassic Park - The Judith River Formation (Montana)

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Troodon
12 minutes ago, -Andy- said:

I see you have found a new way of photographing your raptor teeth.

 

The 8mm tooth is incredible.

 

For the 12mm tooth, wouldn't it be S. langstoni due to upwards pointing serrations?

Ha ha have less lazy so taking the time to do it this way.

Yes, splitting hairs on the 12 mm tooth but it really has not been reported from the JR  (Currie 2013) so who knows

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hxmendoza
On 1/10/2018 at 1:34 PM, Troodon said:

Old teeth new pictures

DromieT.thumb.jpg.74460e72c1f888b390faede8e1c03531.jpgDromTeeth.thumb.jpg.865cdd4189387bd6694caa3b9c3a2611.jpg

 

Beautiful teeth @Troodon.

I do question the 25mm Dromaeosaurus tooth ID. I think it may better fit the first caniniform maxillary tooth of Nanotyrannus. Maybe even the second maxillary tooth. Any pics of the base?

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Troodon
1 minute ago, hxmendoza said:

 

Beautiful teeth @Troodon.

I do question the 25mm Dromaeosaurus tooth ID. I think it better fits the first caniniform maxillary tooth of Nanotyrannus. Maybe even the second maxillary tooth. Any pics of the base?

Thanks, that tooth is Judith River

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hxmendoza
9 minutes ago, Troodon said:

Thanks, that tooth is Judith River

 

Oops!! I didn’t bother reading the formation. Sorry! LOL!

 

Okay then, possibly the first maxillary tooth of a Gorgosaurus-like tyrannosaur (If not Gorgosaurus sp. itself). What do you think?

 

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Troodon

I thought the serration density was different need to recheck and get back.  If they are the same definitely Tyranno.

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Troodon

A few JRF Tyrannosaurid Teeth from my collection

 

TyrannoTeeth4.thumb.jpg.97340022e6c98753a5055bddebcd09fd.jpgTyrannoTeeth3.thumb.jpg.5fd55783c771d1174590c3c41bec8604.jpgTyrannoTeeth2.thumb.jpg.bd7a63ae294d13f47fe6cf1ea77d96d7.jpg

 

Positional Teeth

TyrannoTeeth1.thumb.jpg.66d5b7a6b12026162fe366709c45b421.jpg

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hxmendoza
2 hours ago, Troodon said:

@hxmendoza serration density  that of a Dromie

Okay, good to know. Big tooth!

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-Andy-

Beautiful teeth as always!

 

By the way, Frank, have you ever done a distal mid-crown serration count for your tyrannosaurids? Reading off "Dental Morphology and Variation in Theropod Dinosaurs: Implications for the Taxonomic Identification of Isolated Teeth", I noticed that the distal mid-crown denticle density of Daspletosaurus was in the range of 9.0 - 11.2, while Gorgosaurus was 10.0 - 15.0. We talked briefly about this, but didn't look into it any further.

 

I am curious to see if your bigger "likely-to-be-Daspletosaurus" teeth fulfills this rule too. My 3-incher JRF tyrannosaurd crown (which I like to imagine is Daspletosaurus) has 10/5mm on the midline. Meanwhile, my two smaller JRF tyrannosaurids (1.2 inch crown, and 2 inch crown) have 13 to 14/5mm on the midline. Due to low sampling data on my part, I can't tell if the size of the teeth causes this difference in serration count.

 

Tyrannosaurid count.jpg

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hxmendoza
3 hours ago, Troodon said:

A few JRF Tyrannosaurid Teeth from my collection

 

TyrannoTeeth4.thumb.jpg.97340022e6c98753a5055bddebcd09fd.jpgTyrannoTeeth3.thumb.jpg.5fd55783c771d1174590c3c41bec8604.jpgTyrannoTeeth2.thumb.jpg.bd7a63ae294d13f47fe6cf1ea77d96d7.jpg

 

Positional Teeth

TyrannoTeeth1.thumb.jpg.66d5b7a6b12026162fe366709c45b421.jpg

 

Beautiful. That little rooted posterior tooth is fantastic!

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Bobby Rico

@Troodon your collections are fantastic and this is no exception just stunning and very informative.

 

cheers Bobby 

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Troodon
1 hour ago, -Andy- said:

Beautiful teeth as always!

 

By the way, Frank, have you ever done a distal mid-crown serration count for your tyrannosaurids? Reading off "Dental Morphology and Variation in Theropod Dinosaurs: Implications for the Taxonomic Identification of Isolated Teeth", I noticed that the distal mid-crown denticle density of Daspletosaurus was in the range of 9.0 - 11.2, while Gorgosaurus was 10.0 - 15.0. We talked briefly about this, but didn't look into it any further.

Cheers 

I am curious to see if your bigger "likely-to-be-Daspletosaurus" teeth fulfills this rule too. My 3-incher JRF tyrannosaurd crown (which I like to imagine is Daspletosaurus) has 10/5mm on the midline. Meanwhile, my two smaller JRF tyrannosaurids (1.2 inch crown, and 2 inch crown) have 13 to 14/5mm on the midline. Due to low sampling data on my part, I can't tell if the size of the teeth causes this difference in serration count.

 

 

I did a study on all my Tyranno teeth from the Hell Creek and the size of the tooth has a direct bearing on the density of the serrations.  This is why one cannot generalize about density you need to know the size of the tooth.

Nano Teeth

7/16 to 1" : Serrations Density 4.5 to 3.4/mm

1" to 2" :   Serrations Density 3.1 to 2.7/mm

Rex Teeth

Size:

1/4 to 1" : Serration Density 4.3 to 3/mm

1" to 2" :  Serration Density3.4 to 2.5/mm

2.5 to 3.5" : Serration Density 2 to 1.8/mm

4.5" : Serration Density 1.6/mm

5.3" : Serration Density 1.4/mm

 

In that paper I believe all the teeth fit into a size range.  Anyway my 87mm tooth is 10/5mm and my 52mm one is 12/5mm

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Troodon
27 minutes ago, hxmendoza said:

 

Beautiful. That little rooted posterior tooth is fantastic!

Thanks Henry.  I spoke with Calvin about the size of Dromaeosurus teeth he's seen and they can get quite large he said. 

9 minutes ago, Bobby Rico said:

@Troodon your collections are fantastic and this is no exception just stunning and very informative.

 

cheers Bobby 

Thanks Bobby 

 

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Troodon

@-Andy- updated my rex density from above added a 5.3 tooth

 

Did some more JRF teeth.  Could not do 5mm on all the teeth so adjusted all to 1mm.

 

12mm - 4.5/mm

14mm - 3.3/mm

15mm - 5 to 6/mm

19mm -  3.3/mm

26mm -  3/mm

34mm -  2.6/mm

60mm - 1.8/mm

 

So my 3 3/8 " (87mm) tooth still fits the parameters of being a possible Gorgosaurus but my 60mm one is probably a Daspletosaurus at 9/5mm.  So +3" does not guarantee you a Daspletosaurus, that theory is BUSTED :).    You need to buy a tooth not based on size but serration count :D  but that is still no a guarantee.. it needs to come from a Daspletosaurus graveyard. 

 

When we have this discussion I'm always reminded of this picture I took at the Tyrrell.  Goro teeth can get pretty big.

 

IMG_0710.thumb.JPG.13846716d5e8fb32da5b7c42ff537b18.JPG

 

 

 

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Troodon

@-Andy- Took a look at my Two Medicine teeth comparable view.

My big one looks like Daspletosaurus it's 4" and 9/5mm

Around 2 1/2" they ranged 13 to 15.5/5mm

Around  1 1/2" they ranged 11 to 13/5mm

Don't have any in the 3" range

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bcfossilcollector

Beautiful teeth. Truly stunning. 

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-Andy-

@Troodon Thanks for the info. Any clues to the crown size of that enormous Gorgosaurus?

 

I updated the tyrannosaurid teeth chart for easier reading. The number next to the dinosaur name represents measurements in inches rounded down to 2 decimals.

 

Still trying to understand this data. Only thing I can see is that n average, Daspletosaurus teeth are bigger than Gorgosaurus teeth. The average crown height of Gorgosaurus teeth is 1.592 inches. The average crown height of Daspletosaurus teeth is 2.297 inches. But we already knew Daspletosaurus tend to be bigger.

 

Of note is that ROM1247 used for the Gorgosaurus and MOR590 for Daspletosaurus are subadults. AMNH 5346 is considered an adult (though not the biggest specimen of Daspletosaurus known). BMNH R4863 Gorgosaurus specimen seems to be an adult; some older papers even classify it as a Daspletosaurus but I will need to get more info.

Tyrannosaurid count.jpg

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Troodon

@-Andy-  nice work on that chart easier to read..  Did not have a scale on those teeth from the Tyrrell but they were at least 3".

BTW,   MOR590 is the Two Medicine Formation type specimen Daspletosaurus horneri not D. torous.  My guess is the teeth they used were tied to known skulls so it's somewhat biased based on what they used for the paper.  I think all you can gather from the study is that the density of Gorgo teeth trend higher than Daspleto and can possibly be used to identify Gorgo teeth if greater than 12/5mm and Daspleto if 9/mm but it's an unknown if it fall between those two.  Pretty close tolerances to make that call and if adult skulls were used would the data be different....guess why we ID them as Tyrannosaurid indet.

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Troodon

@-Andy-  check out the chompers on this Gorgo being worked on at the BHI,  cast going to the children's museum of Indianapolis

 

DTTZi1OWkAAek-u.thumb.jpeg.ff9892b033879d5ebd1906330bf7ef6d.jpegDTOEa3CX0AANZ7g.thumb.jpeg.bf24c8128bc8823560ab8b79cd9e71c0.jpeg

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Bobby Rico

@Troodon that is some serious casting work. Kids of Indianapolis are in for a treat.

 

 

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-Andy-

Good gracious. I could have mistaken that for a T-Rex.

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Troodon
14 minutes ago, Bobby Rico said:

@Troodon that is some serious casting work. Kids of Indianapolis are in for a treat.

 

 

Its a beautiful skull believe its from the Two Medicine Fm of Montana.  The original was at the Tucson show a few years ago.   Yep the museum will enjoy it.

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oldtimer

What an awesome cast.  Glad to see it will be on display at a children's museum.

That is sure to spark a big interest from kids as well as their parents.

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