Editing Dimetrodon (section)

==== Jaw joint and ear ====
Another transitional feature of ''Dimetrodon'' is a ridge in the back of the jaw called the reflected lamina, which is found on the [[articular]] bone, which connects to the [[quadrate bone]] of the skull to form the jaw joint. In later mammal ancestors, the articular and quadrate separated from the jaw joint, while the articular developed into the [[malleus]] bone of the [[middle ear]]. The reflected lamina became part of a ring called the tympanic annulus that supports the [[ear drum]] in all living mammals.<ref name=TOL2>{{cite web |url=http://tolweb.org/notes/?note_id=466 |title=Autapomorphies of the main clades of synapsids |last=Laurin |first=M. |author2=Reisz, R.R. |year=1997 |work=Tree of Life Web Project |access-date=24 August 2012}}</ref>