Sacrum--Bison or Something Else?

[Brandy Cole]

The river has been receding daily, and I found this sacrum two days ago laying in sandy gravel that had just been exposed.  Mostly Pleistocene fossils here.  Due to its size, I thought it may be from one of the larger herbivore mammals.  But due to wear, it's a little hard for me to tell how tapered or straight the original structure was, which seems pretty diagnostic in differentiating between the species.  Several examples I've seen look similar, but I'm having a hard time finding any with sizes listed, so I'm a little lost.

 

Can anyone shed some more light on this?  

 

Thank you!

--Brandy

 

 

 

 

 

[Harry Pristis]

 

I think this a horse sacrum based on the two processes shown in the last image.  Bovids don't have these processes.

[val horn]

It is really nice looking  is it fossilized? 

[Brandy Cole]

19 minutes ago, Harry Pristis said:

 

I think this a horse sacrum based on the two processes shown in the last image.  Bovids don't have these processes.

 

Thank you! I can see the differences in the spinous processes of the bovid and horse now that you've mentioned it.

[Brandy Cole]

1 hour ago, val horn said:

It is really nice looking  is it fossilized? 

Thank you! Yes.  I was really excited to find it.

[Brandy Cole]

After further study, I think this one might actually be better identified as camelid.

 

I was recently looking through Olsen's  "Mammal Remains from Archeological Sites" and came across his line drawings for horse sacrums.

 

His horse sacrum drawing had some key differences from mine, especially in the sacral wings and articular processes.  The sacral wings on a horse are much wider, longer, and narrower than the one I found.

 

I found a YouTube video with examples of horse and camel sacrums, and mine appears to be much more similar to camel.  The vertebral foramen are also larger, wider, and deeper set than horse, but strongly resemble the camel example.

 

Camel starts around 13:50

 

It looks like my sacrum broke off at the fourth transverse line, where camels may have a less fused line.

 

[Brandy Cole]

Does anyone have any suggestions on where I could look for size estimates or comparison literature to get a better idea if this is more likely to be paleollama vs a larger camelid?

 

Ventral view length is roughly 228.6mm  and width is roughly 190.5mm.