The definitive mammalian middle ear (DDME) is an amazing organization of bones and soft tissue that give mammals the ability to hear in the broad frequency range that they can. The mammalian ear is substantially different than the reptilian ear from which we supposedly evolved.
So there must have been changes along the way. This is a well documented evolutionary story from the fossil record....
DDME
Modern Mammals all have the DDME. My question is according to the DDME theory above, when did the DDME actually evolve according to the theory. In other words, when did the ossicles separate and form the three bones in the DMME. If I understand correctly, it must have been sometime after Yanoconodon. Is this correct?