Jump to content

Horse, of course?


KingsburyFossilHunter

Recommended Posts

KingsburyFossilHunter

 

Dear Fossil Forum,

 

We have continued to visit the Brazos near Houston, and it has turned up horse. Teeth, a proximal phalange, and what I think is actually not horse, but a tapir calcaneus! 

 

My latest find is a vertebra, and it looks like thoracic vertebra 18 (T18). But, in comparing it to a photo of a modern horse example, the facet for rib attachment is smaller in proportion, and lots of other details look a little different as well. Does anyone know of good resources for researching fossil horse ancestor vertebrae? Or know if there is variation in contemporary vert structure depending if mule, donkey, etc? I also do not have a good sense of scale.

 

Photos attached. As always, thanks for looking :)

 

_MG_4655.jpg

_MG_4654.jpg

_MG_4652.jpg

_MG_4653.jpg

_MG_4650.jpg

_MG_4651.jpg

  • Enjoyed 1
Link to post
Share on other sites
PaleoNoel

@Harry Pristis may be able to help. Looks similar to images I found online.

Link to post
Share on other sites
Harry Pristis

Sorry, vertebrae remain difficult for me.

Link to post
Share on other sites
val horn

Am I seeing  this wrong .  One end of the centrum looks rounded too me.

Link to post
Share on other sites
Thomas.Dodson
3 minutes ago, val horn said:

Am I seeing  this wrong .  One end of the centrum looks rounded too me.

You're not seeing wrong.

 

An assumption made by a lot of people about vertebrae types is that all mammal vertebrae are amphiplatyan; flat on both sides. In reality the function and position of the vertebrae is also a factor.

 

I'm afraid I can't help much with the vert. The best I can offer is pictures for comparison to Bison species if you haven't already ruled them out.

  • I found this Informative 1
  • Learned something new 1
Link to post
Share on other sites
KingsburyFossilHunter

Thomas, I won't complain if you post Bison photos :)

Yes, Val Horn, the vert is convex on one side, concave on the other side of the centrum/body.

Apologies for the contrasty photos, the sun makes me hyper and gets me to get stuff done (like take photos to post).

Link to post
Share on other sites
val horn

Well Thomas D. says I am over simplifying, but how do you rule out croc or other rather large reptile.  

Link to post
Share on other sites
GPayton

I'm not at home with access to my collection right now, and I don't seem to have any good pictures of what I'm looking for, but I've found an almost identical vertebra in the Brazos before. I remember putting it down as an Equus thoracic vertebra, but I think getting either yours or mine down to something as specific as vertebral number is going to be impossible. 

  • I found this Informative 1
Link to post
Share on other sites
Thomas.Dodson
On 3/8/2021 at 5:27 PM, KingsburyFossilHunter said:

Thomas, I won't complain if you post Bison photos :)

Yes, Val Horn, the vert is convex on one side, concave on the other side of the centrum/body.

Apologies for the contrasty photos, the sun makes me hyper and gets me to get stuff done (like take photos to post).

I went and took a look at the partial skeleton I have in storage and I doubt your specimen is Bison. Among the various vertebrae none have a heart shaped/triangular neural canal like your specimen. There are some other differences but this stood out readily as the Bison neural canals in the relevant vert types are round. Equus thoracic verts do seem to have this type of neural canal. Here's a paper that examines Equus thoracic vertebrae through various historical specimens that might help you. Download Link

 

I've attached some bad pictures of some of the Bison verts but you can see the differences in the neural canal.

IMG_7897.thumb.JPG.0c22f79c32e3621c7e750057e27e631c.JPG

IMG_7898.thumb.JPG.7bef92032cad84fe52e01e860bd4c8eb.JPG

  • Learned something new 1
Link to post
Share on other sites
Brandy Cole

I found a similar vert a while back with that had a similar shape with both a convex and concave side.   I was also unable to identify it. Very curious to see any ideas on this thread.

Link to post
Share on other sites
Shellseeker
On 3/6/2021 at 11:37 AM, KingsburyFossilHunter said:

My latest find is a vertebra, and it looks like thoracic vertebra 18 (T18). But, in comparing it to a photo of a modern horse example, the facet for rib attachment is smaller in proportion, and lots of other details look a little different as well. Does anyone know of good resources for researching fossil horse ancestor vertebrae? Or know if there is variation in contemporary vert structure depending if mule, donkey, etc? I also do not have a good sense of scale.

For comparison,

This had been identified as a pre_Equus Horse Vertebra.  It was found in a Bone Valley Phosphate mine, Fort Meade Florida. The width in the 1st photo is 57.1 mm, centrum alone is 20.3 mm

IMG_7617.thumb.JPEG.0c1620033e185f7244aff76fc83f617f.JPEGIMG_7618.thumb.JPEG.27a301794edf6ade5b41f76eaf54128e.JPEGIMG_7619.thumb.JPEG.4a0da9d4ce07240cf3d457f8f456d2d7.JPEG

  • I found this Informative 1
Link to post
Share on other sites
KingsburyFossilHunter
On 3/9/2021 at 1:36 AM, GPayton said:

I'm not at home with access to my collection right now, and I don't seem to have any good pictures of what I'm looking for, but I've found an almost identical vertebra in the Brazos before. I remember putting it down as an Equus thoracic vertebra, but I think getting either yours or mine down to something as specific as vertebral number is going to be impossible. 

Gpayton, I will be curious to see what you have found that is similar, whenever you get home.

 

The reason why I suspect my find may correlate with T18 in a contemporary horse is because there does not seem to be a facet for rib attachment on the back...only the anterior (front). Although my find is a bit worn also in that area on the back.

  • I found this Informative 1
Link to post
Share on other sites
  • 2 weeks later...
KingsburyFossilHunter

Hi everyone,

 

Apologies for slowness in replies, but then again we are in fossil time...

 

 @Shellseeker, thank you so much for your vert photos. Your centrum is actually smaller by a bit than mine, and a bit more delicate in that area, really interesting.

 

@Thomas.Dodson, what a lucky find! I can see how much more 'sturdy' the bison verts are, and also good point on neural canal shapes. Also, thanks for the paper link, I was looking at that too, it might explain the differences in spinous process shapes between my sample and another contemporary sample, looks like it depends on if the horse was ridden or not. 

 

@val horn, from what I have read the croc/alligator verts have different textures, especially on the body/centrum.

 

@Brandy Cole, someday I will get my piece IDed, there is a small museum at Sam Houston State University where I teach that scheduled a fossil ID day just at the start of the pandemic (cancelled). I bet they will schedule another one :)

 

Right now I am thinking contemporary horse (last 400 years), I wonder how many working horses fell into the Brazos River while crossing it or got washed away. 

 

  • Enjoyed 1
Link to post
Share on other sites
GPayton

@KingsburyFossilHunter Sorry I still haven't gotten around to posting my horse vertebra yet, haven't been home in a while. I would like to say though that I'm almost 100% your find isn't contemporary in age. The coloring especially is a dead giveaway for most mineralized bones I've pulled out of the Brazos, although the best way to tell if a bone is fossilized is to heft it and judge if it has a solid weight or not. After that I usually try to scrape some of the outside of the bone as well as some of the inside of the porous cancellous bone with my fingernail - if any flakes off without much pressure and has a generally chalky feel to it, the bone is modern. The burn test everyone often recommends has been hit or miss for me in practice. 

  • I Agree 2
Link to post
Share on other sites
KingsburyFossilHunter

The bone is definitely fossilized. It makes a chinking sound and is pretty heavy. My thought is that it might not be precolumbian horse.

Also, I wonder how long it takes items to fossilize in this region.

I had a layover outside of London once and took the train in and visited the sites along the Thames. There were fossilized bones from abbatoirs there from the victorian era! So, depending on conditions, things can fossilize pretty fast.

Link to post
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
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...