And so on. Despite these differences, all mammals share four traits that are shown in the diagram below: hair, mammary glands, a hinged jaw, and three tiny middle ear bones. Most have specialized ...

Middle ear appeared in amphibians ... In early vertebrates, jaws articulated at the articular (lower) and quadrate (upper) bones. In early mammals, or mammal-like reptiles (therapsids), the jaws ...

As mammals evolved, these bones shifted location and function, becoming essential for transmitting sound vibrations from the eardrum to the inner ear. It’s a transformation almost too wild to believe, ...

(Bottom) Mammals. The schematic on the left shows ... make up two of the three middle ear bones. The schematic on the right shows the middle ear in a human embryo, with the primary jaw joint ...

The opening in the bone is left to close on its own ... Comparative anatomy of eustachian tube and middle ear cavity in animal models for otitis media. Ann. Otol. Rhinol. Laryngol.

One of the distinctive features of mammals is their jaw structure and the presence of three middle ear bones, which ...

Therapsids, the ancient relatives of mammals, once roamed Earth in great ... jawbones that would later evolve into mammals’ middle ear bones. “Gorgonopsians are more closely related to mammals ...