triceratops 

I love the triceratop dinosaurs.

I am often disappointed that most museums display their skulls with the back to the wall. This makes it impossible to see that the skull to first-vertebra joint was a perfect socket and ball joint. The base of the skull has a perfect hemispherical socket for the first-vertebra to sit in. 

I spent decades looking at them before I saw the back of one. All that time I assumed but did not *know* that they would be able to quickly turn their heads. One glance and it is obvious that my assumption was correct.