Jump to content

ThePhysicist

Recommended Posts

Hi y'all, I came across this odd lower mammal molar from the HCF and I still can't make a more precise determination. It doesn't seem to follow the metatherian tooth design, so I guessed it must be eutherian.  It seems to have only four cusps. Any insight is appreciated, and I can provide more photos if need be. @jpc

Edit: I can't seem to tag people, could someone page jpc?

 

IMG_6899.thumb.jpeg.48930a8205c6ac6ac7b609115869d40b.jpeg

IMG_6894.thumb.jpeg.dcbaaf8bb9e06a554b9b875c4b8de950.jpeg

IMG_6896.thumb.jpeg.70f4da67ee173a574cf4aa5ac5c8a13f.jpeg

2098408764_IMG_68982.thumb.jpeg.e6233671f7d098dd8c3189ca7b6be50a.jpeg

IMG_6898.thumb.jpeg.595b44711973ff7ae7b58c94a54c3779.jpeg

Edited by ThePhysicist
  • Enjoyed 1

"Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan

"I was born not knowing and have had only a little time to change that here and there." - Richard Feynman

 

Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | SquamatesPost Oak Creek | North Sulphur RiverLee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone

Instagram: @thephysicist_tff

Link to comment
Share on other sites

@jpc

 

Coco

----------------------
OUTIL POUR MESURER VOS FOSSILES : ici

Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici
Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici
Mâchoires sélaciennes récentes : ici
Hétérodontiques et sélaciens : ici
Oeufs sélaciens récents : ici
Otolithes de poissons récents ! ici

Un Greg...

Badges-IPFOTH.jpg.f4a8635cda47a3cc506743a8aabce700.jpg Badges-MOTM.jpg.461001e1a9db5dc29ca1c07a041a1a86.jpg

 

Link to comment
Share on other sites

Here I am.  Referring to your last photo, there is fifth cusp on the talonid (the lower half of the tooth seen in the left half of said photo.  Where your blue line bends along the bottom edge close to the leftmost cusp.  This is a a marsupial (metatherian) characteristic.  On the other hand, there are only two cusps on the taller part (the trigonid), and that is confusing and non-marsupialian.  So, I stand with you... uncertainty rules.  I only checked Lillegraven's Mesozoic mammals book.   there are other sources out there to look at.  

 

Edited by jpc
  • I found this Informative 1
Link to comment
Share on other sites

9 hours ago, jpc said:

Referring to your last photo, there is fifth cusp on the talonid (the lower half of the tooth seen in the left half of said photo.  Where your blue line bends along the bottom edge close to the leftmost cusp.

Okay, I saw that but it's so subdued I didn't consider it one. Here are some more photos, not that it helps the ID:

Indet.thumb.jpg.7cc42d86eca6e1c319aae490b3f02d03.jpg

 

9 hours ago, jpc said:

On the other hand, there are only two cusps on the taller part (the trigonid), and that is confusing and non-marsupialian.  So, I stand with you... uncertainty rules.  I only checked Lillegraven's Mesozoic mammals book.   there are other sources out there to look at.  

Thanks for your input, ya two cusps on the trigonid is odd, it's not broken and doesn't appear pathological? I've so far referenced the publications below, and yet to see something resembling it. I think I'll reach out to a few other professionals to see if it's interesting.

 

* Clemens, William A. Fossil Mammals of the Type Lance Formation, Wyoming. Part II, Marsupialia. University of California Press, 1966.

* Kielan-Jaworowska, Zofia, et al. Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure, Columbia University Press, 2004. 

* Wilson Mantilla GP et al. 2021 Earliest Palaeocene purgatoriids and the initial radiation of stem primates. R. Soc. Open Sci. 8: 210050.
https://doi.org/10.1098/rsos.210050

* Richard C. Fox. 2015. A revision of the Late Cretaceous–Paleocene eutherian mammal Cimolestes Marsh, 1889. Canadian Journal of Earth Sciences. 52(12): 1137-1149. https://doi.org/10.1139/cjes-2015-0113

 

18 hours ago, Coco said:

@jpc

 

Coco

I also can't react to posts, thank you!

"Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan

"I was born not knowing and have had only a little time to change that here and there." - Richard Feynman

 

Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | SquamatesPost Oak Creek | North Sulphur RiverLee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone

Instagram: @thephysicist_tff

Link to comment
Share on other sites

  • 4 weeks later...
On 10/18/2023 at 8:49 AM, jpc said:

Here I am.  Referring to your last photo, there is fifth cusp on the talonid (the lower half of the tooth seen in the left half of said photo.  Where your blue line bends along the bottom edge close to the leftmost cusp.  This is a a marsupial (metatherian) characteristic.  On the other hand, there are only two cusps on the taller part (the trigonid), and that is confusing and non-marsupialian.  So, I stand with you... uncertainty rules.  I only checked Lillegraven's Mesozoic mammals book.   there are other sources out there to look at.  

I just checked Lillegraven 1969 (linked), and I think it's a dead ringer for Gypsonictops P4:

37132530_Screenshot2023-11-12at10_06_19PM.png.0d615d501de6194c90b1e05c36fe4a6d.png

1207984973_Screenshot2023-11-12at10_06_13PM.png.a2a6894ddc8366a578e2244c6023e48f.png

 

66829098_Screenshot2023-11-12at10_06_07PM.png.56f206d5d46041c8217c1b06392405f1.png

 

Looks like a pretty interesting phylogeny, being an early eutherian with potential relation to insectivores, rodents, and primates!

908166218_Screenshot2023-11-12at10_13_58PM.thumb.png.09539ed475dcb0d969c678b442670996.png

  • I found this Informative 2

"Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan

"I was born not knowing and have had only a little time to change that here and there." - Richard Feynman

 

Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | SquamatesPost Oak Creek | North Sulphur RiverLee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone

Instagram: @thephysicist_tff

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...