In amphibians & stem reptiles, the dermal skull roof is unbroken except for openings for eyes & nasal openings ... In most lizards, bar closing the lower fossa has been lost in lizards, leaving a ...

Moose is ‘true synapsid’ skull. Temporal fossa separated from anterior orbit by post-orbital bar ... With loss of bones, switch to bones articulating hinge between upper and lower jaw. Amphibian, ...