Reconstruction of the late Pleistocene human skull from Hofmeyr, South Africa

Human skeletal remains from sub-Saharan Africa are virtually non-existent for the period when genetic models indicate the first modern human emigration from this region. The skull from Hofmeyr, South Africa, which has been dated to c. 36 ka, is one of the only specimens known from this critical part of the late Pleistocene. The Hofmeyr skull was largely intact at the time of its discovery but has suffered post-recovery mishandling, with the resultant loss of most of the lower facial skeleton, the mandibular angle, the right mastoid process, and much of the occipital. Given the potential significance of this specimen, we have undertaken its restoration and reconstruction so as to provide a more complete picture of the cranial morphology of the late Pleistocene population from which it derived. On the basis of photographs, measurements, and morphological description recorded prior to its having been damaged, we reconstructed some of the missing bone in modeling clay on a high resolution plastic cast of the cranium. The original specimen was CT scanned, as was the cast with the reconstructed maxilla and mastoid; these scans were employed in the final computer reconstruction of the skull. Virtual reconstruction of the remainder of the cranium was accomplished using mirror-imaging and reference-based methods, employing 3D geometric morphometrics from a sample of recent human crania to compute coordinate-based estimates of the missing parts. This reconstruction provides a more complete picture of the Hofmeyr cranium and serves as a basis for more comprehensive morphometric comparisons.