Figure 10.

Results of a principle components analysis of 121 adult crania sorted into six distinct population groups. The first two principle components account for 54.44% of total shape variation. Principle component 1 accounts for 36.20% of shape variation, and principle component 2 accounts for 17.24% of shape variation. Deformed thin plate splines are displayed along their respective axes. The greatest shape variation, as illustrated by the thin plate splines along principle component 1, is evidenced by an inverse relationship between the sagittal and transverse dimensions of the foramen magnum. The shape variation along the second principle component is characterized by an inverse relationship between the oblique axes of the foramen magnum, that is, between anterior right and posterior left and anterior left and posterior right dimensions. The specimen located at the farthest point in the positive direction along principle component 1 is a cranium of a 70-year-old Bengali male, which possesses a shape that is elongated in the anterior-to-posterior direction relative to a narrow right-to-left dimension. Conversely, the cranium at the farthest negative point along the first principle component that of a 60-year-old Peruvian female is marked by a shape that is narrow in the anterior-to-posterior direction relative to an elongated right-to-left dimension