Early closure of this cranial suture caused the boy's skull to be asymmetrical. More striking, the researchers noted in their study, was the person's abnormally shaped upper jaw, coupled with at ...

The extended lower jaw of Alienacanthus, twice as long as the skull, is unique among placoderms and extremely rare in other living and fossil groups. In most animals, jaw protrusion is seen in the ...

Modern mammals evolved from within a group of animals called Cynodonts. These had a jaw joint consisting of two separate bones - the quadrate of the skull and the articular in the lower jaw and ...