The human cranium and the facial bones are the foundation for the soft tissues of the face and head. Thus, much of the visible appearance of the human face depends upon the shapes and qualities of these bones. The cranium is that part of the skull that holds and protects the brain in a large cavity, called the cranial vault. Eight plate-like bones form the human cranium by fitting together at joints called sutures. The most important of these cranial bones for the appearance of the face is the frontal bone, which underlies the top of the face above the eyeballs. The human skull also includes 14 facial bones that form the lower front of the skull and provide the framework for most of the face that is important to psychological research. These 22 skull bones form other, smaller cavities besides the cranial vault, including those for the eyes, the internal ear, the nose, and the mouth. The important facial bones include the jaw bone or mandible, the maxilla or upper jaw, the zygomatic or cheek bone, and the nasal bone.
The shapes and features of the human skull determine much of the static appearances of the face and provide the basis for the features of physiognomy. Forensic pathologists and biologists can reconstruct the superficial appearance of a face merely from the human skull, as in the case of the Kennewick Man. The reconstruction of this skull revealed a facial appearance that indicates he is a descendant of a more ancient migration from Asia than that which brought the ancestors of the Indians (Amerinds), who settled widely in the Americas before the arrival of Europeans.
The skull bones are associated with many other features. Processes are areas where the bones have extra tissue to hold muscles and ligaments; lines are grooves in the bone from other developmental processes; foramina are holes in the bones through which nerves and blood vessels pass; sinuses are empty spaces in the bones that make the skull lighter. Some of these features affect the physiognomy of the face due to variations in thickness, size, location, and shape.
The diagrams below show the major external features of the human cranium and the major skull bones. The names in black are facial bones, those in red are cranial bones, and those in blue are features of the bones.
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