this is the underside of the skull. the large hole in the back of the skull is where the spinal cord attached. the two bulbous structures to either side of that are where the rest of the internal ear structures hang out protected in thier own little sounding chambers the two holes in the back of the jaw on the upper palate are nasal cavities. now you know why your nose drains down the back of your neckhole when you have a cold. i think the two smaller holes forward of that are muscle attachments but i am way rusty on all that anymore. notice how human like the molars are. also of note is how far out the cheek bone structures arch. up through them the bottom jaw bones thrust and attach to form that hinge joint. the two bones do not touch though.