So I have this mysterious bone...

November 21, 2019 12:41 PM

It was given to me by a friend who found it on his land near Mariposa, CA, USA, just outside Yosemite National Park. It's huge, about 6 inches wide and 4 inches tall. I'd love to identify it - what animal and what specific vertebra? Photo album here.

My friend thinks it might be from a bear, but I'm not so sure. Here are photos of all the vertebrae of a black bear (Ursus americanus), and it doesn't seem to be any of them.

It doesn't seem to have a spinous process, and it has some holes which look a lot like sacral foramina, which makes me think it's part of the sacrum.

Thanks for any clues!

posted by danceswithlight to Science & Nature (9 answers total)

It's a vertebrae, it's just worn and various bits are broken off. The holes are where the nerve roots exit- all vertebrae have transverse foramen, not just the sacrum.

I don't know what animal it's from but you could probably take it in to your local DNR or Fish and Wildlife office and they'd tell you.
posted by fshgrl at 1:04 PM on November 21, 2019

Here are the 90 species of mammals in Yosemite. (select Mammals and click on Get Checklist) There are no moose, so the only really large ones are bears, deer, sheep and mountain lions. I'm not finding specific vertebrae bone sizes for those, but what you have seems to big to be anything but a bear. Of course, it could also be a cow or a horse, if that land was farmed at some point.
posted by beagle at 2:09 PM on November 21, 2019 [2 favorites]

I think it's what's called the atlas vertebrae in a human - the one the the skull rests on.
posted by bonobothegreat at 4:15 PM on November 21, 2019

...I'm going to say horse (top right)
posted by bonobothegreat at 4:36 PM on November 21, 2019 [1 favorite]

Best answer: I am almost certain that is from a bison. Check out the atlas vertebrae here.
posted by DSime at 7:06 PM on November 21, 2019

Response by poster: Yes, after looking closely at the C1 (atlas) vertebra of the deer (too small), horse (the foramina point in a different direction), I think the bison is a near-perfect match :)

As a side note, only cervical and sacral vertebra have transverse foramina. The thoracic and lumbar vertebrae do not. Comparison chart.
posted by danceswithlight at 8:41 PM on November 21, 2019

Best answer: I think it's a cow.
posted by WalkerWestridge at 9:07 PM on November 21, 2019

Response by poster: Agreed, cow seems like a near-perfect match too, and generally more likely. But that part of California is just barely within the historical range of bison.
posted by danceswithlight at 9:27 PM on November 21, 2019

Response by poster: Ah, the size is yet another clue! Thanks to the rulers included for scale in the photographs, it looks like this bison atlas is about 19.5 cm (7.7 inches) wide, whereas this cow atlas is about 14.5 cm (5.7 inches) wide.

Given that my specimen is about 15.5 cm (6.1 inches) wide, it seems much more likely to be a cow than a bison. Although I suppose it could still be a small bison.
posted by danceswithlight at 9:39 PM on November 21, 2019 [2 favorites]