My daughter found this bone on the beaches of Bagamoyo on the Indian ocean coast of Tanzania a couple of years ago. It appears to be a vertebrae but strangely it has multiple rows of teeth on the distal aspect. Could anyone help me with its identification please. I am aware sharks from the carboniferous period had teeth on other parts of their body such as their heads and dorsal fins, but this is very strange.
Andy (I apologise for the green pen, my young daughter got hold of it to colour in!)