Anewly discovered mammal fossil may give clues to how bones in the middle ear evolved from jaw bones, according to a study published in Science yesterday (December 5). The malleus, incus, and ...

i. Decrease in number of bones comprising lower jaw In mammal, dentary is single bone on each side of the lower jaw. ii. With loss of bones, switch to bones articulating hinge between upper and lower ...

Two new studies offer insights into the evolution and development of external ears, which appear in humans and other mammals ...

Vibration via the jaw and skull would have stimulated the patches of sensory cells (maculae of inner ear). This mechanism was improved by incorporating a reduced stubby hyomandibular bone into the ...

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 ...

The dentary expanded to become the entirety of the lower jaw, a single bone that afforded synapsids stronger bites.

mammals have a jaw that’s made of only one bone. A reptile’s jaw is made of several bones fused together. So that freed up two bones, which moved and shrank and eventually became the malleus ...