This week I have another guest mystery object for you, found on a beach by the family of one of my museum colleagues:
Let me know your thoughts about the species, where in the body this particular bone came from, and any other deductions you might have about the animal? I look forward to seeing if you agree with my thoughts!
Zygoma 
The element is easier than than the taxon. It is a thoracic vertebra from a mammal because it has zygapophyses (so therefore not a fish), flat centrum faces (so therefore not bird or reptile), and rib articulation facets (so therefore not from the neck, lumbar or tail regions). Which mammal is less easy, I’m pretty sure it is isn’t a relative of flipper, but that’s all I’ve got now.
Dorsal indeed…. Paolo’s reach is far. When i search for phocidae spines… Paolo’s been there and left his like!
My AI overloard states: Seals have 7 cervical vertebrae, typically 15 thoracic vertebrae, and 5 lumbar vertebrae. Some sources note that Odobenus rosmarus and Hydrurga leptonyx may have 14 thoracic and 6 lumbar vertebrae.
My guess is T3 of the OG Gandolf type.
Elton be proud of me?
There’s no hiding on the internet apparently….
I think Thoracic vertebrae number 7 of a Phoca vitulina.
I thin you are correct, although using this image here https://www.flickr.com/photos/jrochester/14181517647 I would suggest that it is a little more anterior of T7.
T5 perhaps?
Yes… it looks more like T5 with this photo!