Describe the shape of the cranium, size of cranium relative to the face, and prominence of the forehead.

Facial Shape – Describe whether the face is broad or narrow, dish-shaped or protruding face, and the prominence of a brow ridge.

Prognathism – Describe whether the species displays pronounced prognathism or reduced prognathism.

Jaw Build – Describe jaw thickness, presence/absence of a chin, and jaw curvature.

Teeth – Describe the degree of tooth differentiation, prominence of canine teeth, and shape of molars.

Table 1. Features of great ape skulls

Great Ape Species	Cranial Shape	Face Shape	Prognathism	Jaw Build	Teeth
Orangutan
Gorilla
Chimpanzee