| Abstract: | Split-line patterns are reported in skulls of five adult male baboons. While variations in pattern occur in all parts of the skull, these variations are relatively minor in the following regions: supraorbital, lateral orbital, medial orbital, nasal bones, zygomatico-alveolar crest, nasal opening, alveolar process of maxilla and mandible. Wide differences in pattern occur in these regions: infraorbital, zygomatic bone, body of maxilla, and frontal bone posterior to the supraorbital area. The major variability in split-line orientation indicates that oversimplified interpretations of the patterns in terms of (1) conformity to gross structure, or (2) direction of bone growth, are untenable. The variations do not contradict a functional interpretation in which mechanical forces and skull form interact to different degrees in different individuals, however. Skulls of a variety of primates are useful for functional analysis, because they have similar structural plans, but the differences are well outside the normal range of variation for a single species. |
