My Tyrannosaur research

[dinosaur man]

I have been busy, haven’t had much time to research on stuff like this because of COVID-19 but my word document is almost completed for now.  And I found this that further more supports my idea on there rising water levels I mentioned before https://pubs.geoscienceworld.org/paleobiol/article-abstract/45/1/136/570547/Paleocommunity-mixing-increases-with-marine?redirectedFrom=fulltext.

[dinosaur man]

I have just found some evidence that Daspletosaurus could be present in the Horseshoe Canyon Formation.  I’ve found two teeth with large arcute wrinkles, which is only a characteristic of Daspletosaurus teeth as Philip Currie has told me before.  Any thoughts?  I’ll post the teeth later.

[Kane]

So, you just found teeth in Alberta? 

[dinosaur man]

1 hour ago, Kane said:

So, you just found teeth in Alberta? 

Sorry, didn’t explain that, I found them after looking for stuff on the internet about this.  And seen photos of the different sides showing the wrinkles.  But also hopefully next year I might be going back to Alberta, so I can also find my own evidence.

[dinosaur man]

Here’s the teeth, the first one has more visible wrinkles, while the second not as much, all the wrinkles are circled in red.  What does everyone think?

[Troodon]

Not sure those are the type of wrinkles P. Currie was talking about especially on a Premaxillary tooth.  He's the expert on this not us so I would suggest you continue your communications with him.

[dinosaur man]

@Troodon Thank you!  I will 

[dinosaur man]

Hi @Troodon, Phillip Currie just got back to me and said that these teeth aren’t Daspletosaurus.  But he gave me this, if any Tyrannosaur teeth have these from the areas where Daspletosaurus are found, then it’s a Daspletosaurus tooth.  Recently it seems a lot easier to ID Daspletosaurus and Gorgosaurus teeth then ever before!

 

[dinosaur man]

I have calculated a size range for this species (with help and measurements from Jared Voris).  With small adults of this species ranging at 28 feet and 1700 kg to the largest individuals ranging at max 34.2976 feet and 2391 kg!  Average is at 31.2976 feet and 2091 kg.

[dinosaur man]

Jared Voris has been helping me out so far with my project!  And had recently given me the photos of specimen TMP 1985.062.0001 one of the best Dinosaur Park Formation Daspletosaurus sp. specimens!  I wish I could show them but it’s against the rules, so here is a drawing I did of it.

[Strepsodus]

On 05/06/2020 at 5:06 AM, dinosaur man said:

I have calculated a size range for this species (with help and measurements from Jared Voris).  With small adults of this species ranging at 28 feet and 1700 kg to the largest individuals ranging at max 34.2976 feet and 2391 kg!  Average is at 31.2976 feet and 2091 kg.

Good luck with your research.  For the length of the dinosaurs, I would advise giving all lengths to 2 significant figures.  As with many sciences, finding the length of dinosaurs gives a numerical value which is more a rough estimate than an exact number.  Your estimate for the maximum length and average length is rounded to the nearest 0.0001 foot, which is only approximately 30 micrometers, which is smaller than some cells.  Therefore, it would be impossible to estimate the length of a dinosaur to such accuracy.  I would also advise giving the mass to 2 sf.  The exact density of each soft tissue making up a dinosaur, and the amount of each tissue present, is impossible to know, and also the mass of the dinosaur would fluctuate slightly as fluid levels in the dinosaur change, so like the length, the mass can only be roughly estimated.

 

Hope this helps.

[dinosaur man]

7 minutes ago, Strepsodus said:

Good luck with your research.  For the length of the dinosaurs, I would advise giving all lengths to 2 significant figures.  As with many sciences, finding the length of dinosaurs gives a numerical value which is more a rough estimate than an exact number.  Your estimate for the maximum length and average length is rounded to the nearest 0.0001 foot, which is only approximately 30 micrometers, which is smaller than some cells.  Therefore, it would be impossible to estimate the length of a dinosaur to such accuracy.  I would also advise giving the mass to 2 sf.  The exact density of each soft tissue making up a dinosaur, and the amount of each tissue present, is impossible to know, and also the mass of the dinosaur would fluctuate slightly as fluid levels in the dinosaur change, so like the length, the mass can only be roughly estimated.

 

Hope this helps.

Ok, Thank you! 

[dinosaur man]

Have been doing a lot of research on this subject recently as Jared Voris is helping me out on it, and have found out that there are many differences that show Daspletosaurus sp. is not the same as Daspletosaurus torosus, as I got to look at many photos of fossils of the two species!  What does everyone think?

Also here is that Tyrannosaur femur (I confirmed that it was a femur and indeed a Tyrannosaur femur by Caleb Brown) I’ve been researching on it and found out the animal it came from was around 19 to 21 feet long, 6.5 to 7 feet high at the hips, 7.5 to 8 feet high at the top of the head, and had a about 70 cm skull.  Hopefully next year when I go back I could possibly find the rest of the skeleton!  BTW I made the skeletal.  So what does everyone think?

 

[dinosaur man]

A drawing I did of what a juvenile Daspletosaurus sp. would look like based of specimen TMP 2013.018.0011, a 12 foot long juvenile Daspletosaurus sp. from the Dinosaur Park Formation of Dinosaur Provincial Park, Alberta, Canada.

[dinosaur man]

Replicas of Daspletosaurus sp. teeth from the Dinosaur Park Formation of Alberta, Canada.  The teeth are identifiable as Daspletosaurus because the teeth have Enamel Wrinkles the same ones Philip Currie showed me, and the size in general as they are 11.5 cm! 

[TyBoy]

I can see that size matters but not seeing the diagnostic wrinkles you mention or any serrations 

[dinosaur man]

@TyBoy here’s a photo that shows some of the wrinkles.

[The Amateur Paleontologist]

Hey @dinosaur man

Been following this thread for quite some time, I think what you're doing is quite interesting. The biogeography, ecology and taxonomy of North American tyrannosaurs are rather fascinating topics to look into. 

Just to know, what's the 'end goal' of this research project you're working on? I'm quite curious.

[dinosaur man]

2 hours ago, The Amateur Paleontologist said:

Hey @dinosaur man

Been following this thread for quite some time, I think what you're doing is quite interesting. The biogeography, ecology and taxonomy of North American tyrannosaurs are rather fascinating topics to look into. 

Just to know, what's the 'end goal' of this research project you're working on? I'm quite curious.

@The Amateur Paleontologist Thank you!  My end goal is to further the understanding of Tyrannosaurs (evolution, biology, so on...) but specifically the newly named clade Daspletosaurini and one of its most unknown and mysterious animals, the Daspletosaurus sp. as it has been known for over 100 years and not much is known on it.  It could also help with learning a lot more on Tyrannosaurs, and the animals of it’s time!  But I still have a fair amount of work on it, and next year I will be going back to Alberta to do some field work!  But Tyrannosaurs specifically Daspletosaurus has been one of my most favourite Dinosaurs since I was 3, so it’s a fun project for me too!

[Arion]

On 7/1/2020 at 12:57 AM, dinosaur man said:

Have been doing a lot of research on this subject recently as Jared Voris is helping me out on it, and have found out that there are many differences that show Daspletosaurus sp. is not the same as Daspletosaurus torosus, as I got to look at many photos of fossils of the two species!  What does everyone think?

Also here is that Tyrannosaur femur (I confirmed that it was a femur and indeed a Tyrannosaur femur by Caleb Brown) I’ve been researching on it and found out the animal it came from was around 19 to 21 feet long, 6.5 to 7 feet high at the hips, 7.5 to 8 feet high at the top of the head, and had a about 70 cm skull.  Hopefully next year when I go back I could possibly find the rest of the skeleton!  BTW I made the skeletal.  So what does everyone think?

 

 

Nice skeletal restoration  

 

Here are some thoughts on the instagram post. I wouldn't be surprised if the DP Daspletosaurus is a different species from D. torosus. Phil Currie has thought that for almost 20 years (Currie, P.J. 2003. Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Acta Palaeontologica Polonica 48 (2): 191–226. https://www.app.pan.pl/archive/published/app48/app48-191.pdf pp. 221-222). So you're probably right, I just don't agree with the reasons you listed.

 

You use images of two Daspletosaurus skulls to illustrate your point about there being two different species. Interestingly, Currie considers both of the skulls you've shown here to belong to the unnamed DP Daspletosaurus species (or at least he did in 2003, see table on page 222 in the above paper). Furthermore, although I'm not personally familiar with CMN 11594 (Currie says it's comprised of a "scattered skull" from the DP Formation), the illustration indicates that the only preserved cranial elements are the lacrimal and postorbital; the rest is restored from D. torosus. So I think you could have chosen a better representation of D. torosus to make your point.

 

You've listed six ways in which Daspletosaurus torosus differs from the DP species; great! However, you've also restated the same idea three times in that list in a vague and subjective manner ("longer skull vs shorter skull" "taller skull" "skull more compact" are really saying the same thing). If you provide some measurements and show how they relate to each other, that would be much more useful because then we can go and confirm your results (for example, "the length:height ratio of D. torosus is x:y, whereas in the DP species it's x:z"). You have to be able to express what you're seeing in a way that other people can understand . Your assessment of the mandibular elements (angular and surangular) has the same issue, because simply saying they're "larger" is unclear. Are they taller, longer, wider, heavier, all of the above? Are we talking absolute measurements, or in relation to something else on the skull? I assume what you mean is that the region of the mandible posterior to the dentary is proportionately larger relative to the dentary in D. torosus, but that isn't explicitly stated so I can't be sure. This sort of thing becomes a bigger problem when you consider that not everyone who will read your research speaks English as their first language, so things need to be communicated so there's as little room for doubt as possible about what you're talking about.

 

This issue reoccurs in describing the lacrimals ("long low brow horns vs. high short more pointed"). Get some measurements; can this be expressed as a ratio? Is the peak of the lacrimal horn higher relative to another bone on the skull in one species or the other? Is this consistent across multiple specimens? Could it have changed as the animal matured? Furthermore, I don't think this can be established from the images you've chosen, because the lacrimal-nasal contact is restored incorrectly in CMN 11594. In TMP 85.62.1 the posterior edge of the nasal almost reaches the apex of the lacrimal horn, whereas CMN 11594 is restored with the preserved bones placed too high on the skull and as a result the top of the nasal appears to be entirely below the lacrimal. Compensating for errors in reconstruction, they're actually quite similar. This is the same problem you had earlier with the Tumbler Ridge tyrannosaur restoration; schematic drawings like this aren't really useful for making critical anatomical observations.

 

The way to think about coming up with a diagnosis (list of features that are unique to that species) for a fossil is to ask, 'If I found this in the field, would this prove that this fossil belongs to species A and not species B?' This is the problem with your observations on dentary tooth count. You've observed there's a possibility for overlap in the number of dentary teeth in these two species (one is 16-17, the other is 17-18); so if I found a dentary with 17 teeth and nothing else, I'd have no way of knowing which species it was from, because both of them could have 17 teeth.

 

So I think the DP Daspletosaurus is probably a new species, but not for the reasons you cited above.

 

[dinosaur man]

1 hour ago, Arion said:

Nice skeletal restoration  

 

Here are some thoughts on the instagram post. I wouldn't be surprised if the DP Daspletosaurus is a different species from D. torosus. Phil Currie has thought that for almost 20 years (Currie, P.J. 2003. Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Acta Palaeontologica Polonica 48 (2): 191–226. https://www.app.pan.pl/archive/published/app48/app48-191.pdf pp. 221-222). So you're probably right, I just don't agree with the reasons you listed.

 

You use images of two Daspletosaurus skulls to illustrate your point about there being two different species. Interestingly, Currie considers both of the skulls you've shown here to belong to the unnamed DP Daspletosaurus species (or at least he did in 2003, see table on page 222 in the above paper). Furthermore, although I'm not personally familiar with CMN 11594 (Currie says it's comprised of a "scattered skull" from the DP Formation), the illustration indicates that the only preserved cranial elements are the lacrimal and postorbital; the rest is restored from D. torosus. So I think you could have chosen a better representation of D. torosus to make your point.

 

You've listed six ways in which Daspletosaurus torosus differs from the DP species; great! However, you've also restated the same idea three times in that list in a vague and subjective manner ("longer skull vs shorter skull" "taller skull" "skull more compact" are really saying the same thing). If you provide some measurements and show how they relate to each other, that would be much more useful because then we can go and confirm your results (for example, "the length:height ratio of D. torosus is x:y, whereas in the DP species it's x:z"). You have to be able to express what you're seeing in a way that other people can understand . Your assessment of the mandibular elements (angular and surangular) has the same issue, because simply saying they're "larger" is unclear. Are they taller, longer, wider, heavier, all of the above? Are we talking absolute measurements, or in relation to something else on the skull? I assume what you mean is that the region of the mandible posterior to the dentary is proportionately larger relative to the dentary in D. torosus, but that isn't explicitly stated so I can't be sure. This sort of thing becomes a bigger problem when you consider that not everyone who will read your research speaks English as their first language, so things need to be communicated so there's as little room for doubt as possible about what you're talking about.

 

This issue reoccurs in describing the lacrimals ("long low brow horns vs. high short more pointed"). Get some measurements; can this be expressed as a ratio? Is the peak of the lacrimal horn higher relative to another bone on the skull in one species or the other? Is this consistent across multiple specimens? Could it have changed as the animal matured? Furthermore, I don't think this can be established from the images you've chosen, because the lacrimal-nasal contact is restored incorrectly in CMN 11594. In TMP 85.62.1 the posterior edge of the nasal almost reaches the apex of the lacrimal horn, whereas CMN 11594 is restored with the preserved bones placed too high on the skull and as a result the top of the nasal appears to be entirely below the lacrimal. Compensating for errors in reconstruction, they're actually quite similar. This is the same problem you had earlier with the Tumbler Ridge tyrannosaur restoration; schematic drawings like this aren't really useful for making critical anatomical observations.

 

The way to think about coming up with a diagnosis (list of features that are unique to that species) for a fossil is to ask, 'If I found this in the field, would this prove that this fossil belongs to species A and not species B?' This is the problem with your observations on dentary tooth count. You've observed there's a possibility for overlap in the number of dentary teeth in these two species (one is 16-17, the other is 17-18); so if I found a dentary with 17 teeth and nothing else, I'd have no way of knowing which species it was from, because both of them could have 17 teeth.

 

So I think the DP Daspletosaurus is probably a new species, but not for the reasons you cited above.

 

Thank you!  I will work on finding even more in-depth answers!

[dinosaur man]

And so far through my studies I’ve found out that the Dinosaur Park Formation and other Formations where probably a lot more diverse then previously thought as the Dinosaur Park Formation most likely having Alvarezsaurs like the later Horseshoe Canyon Formation, and Large Mega Hadrosaurs that where around 40 feet long!  Though both haven’t been found but studying other Formations extremely similar, it is most definitely possible!

[dinosaur man]

Lists of Dinosaur Park Daspletosaurus sp. specimens

[Arion]

@dinosaur man One suggestion, it’s good practice to cite your sources, especially if you directly quote from someone else’s data

 

https://www.theropoddatabase.com/Tyrannosauroidea.html

[musicnfossils]

What “field work” do you plan on doing out here in Alberta? Are you lining up volunteer work with the museum or just searching for and photographing fossils in the park?