The ability of the tympanum and stapes to effectively transmit vibrations is called impedance matching.
Instead, these thick stapes may have functioned to support the tissue that covers the otic notch.
The second is a congenital malformation of the stapes.
The procedure creates a tiny opening in the stapes (the smallest bone in the human body) in which to secure a prosthetic.
This consists of two ossicles: the columella (equivalent to the stapes of higher vertebrates) which is fused to the skull, and the operculum.
It passes through the ring of the stapes and divides into supraorbital, infraorbital, and mandibular branches which follow the three divisions of the trigeminal nerve.
It also has no tympanic annulus and stapes, making it probably extremely hard of hearing.
However, in early amphibians the stapes was too large, making the footplate area oversized, preventing the hearing of high frequencies.
