An examination of the meaning of cranial discrete traits for human skeletal biological studies.

TLDR: It is concluded, on the basis of these findings, that discrete traits in isolation are not of paramount value to skeletal genetic studies, but may be vital in comparison and conjunction with other types of data in analyzing the population genetics of extinct groups.

Abstract: Discrete traits are of increasing interest in comparative skeletal biological research. Characteristics justifying their use have been investigated primarily in mice, however. Using 72 discrete variants, 321 human skulls from the Terry Collection of known race, sex and age have been studied. Significant sex and age differences were detected. Inter-trait correlation was found to be at a low but significant overall level. Multivariate comparison with conventional craniometric analysis was undertaken on subdivisions of the sample, and distance based on metric and nonmetric data were concordant. It is concluded, on the basis of these findings and the discontinuous variant frequency distributions, that discrete traits in isolation are not of paramount value to skeletal genetic studies, but may be vital in comparison and conjunction with other types of data in analyzing the population genetics of extinct groups.