New Late-Pleistocene uranium–thorium and ESR dates for the Singa hominid (Sudan)

The Singa (Sudan) calvaria has been interpreted previously as a terminal Pleistocene modern human fossil, perhaps related to the Bushman of Southern Africa. Here we report new mass-spectrometric U–Th dates for the calcrete deposit enclosing the fossil teeth and the calvaria itself and new electron spin resonance (ESR) dates for associated dental materials. The new data constrain the age of the hominid to at least 133±2 ka. Together with the preferred linear uptake (LU) ESR dates, the U–Th data confirm that the intriguing mixture of modern and archaic characteristics in the Singa specimen date from isotope stage 6. Far from being a modern human fossil, it represents a rare example of an archaic African population which may have been ancestral to all modernHomo sapiens.     

Rare temporal bone pathology of the Singa calvaria from Sudan

Evidence has recently accumulated that the Singa calvaria from Sudan probably dates from Oxygen Isotope Stage 6 (>130 ka). Morphological studies have indicated a mixture of archaic and more modern human traits, but such analyses are complicated by the possibility that the vault is pathologically deformed, although the exact etiology has not been established. Now computed tomography (CT) has revealed that the right temporal bone lacks the structures of the bony labyrinth. The most likely cause of this rare pathological condition appears to be labyrinthine ossification, in which newly deposited bone obliterates the inner ear spaces following an infectious disease or occlusion of the labyrinthine blood supply. A possible cause of vascular compromise could have been the presence of an expanding acoustic neuroma in the internal acoustic meatus, which is suggested by a significantly wider right meatus compared with the left side. Interestingly, labyrinthine ossification is also consistent with the controversial diagnosis that an anemia caused the characteristic diploic widening at the parietal bosses, because prime etiological factors of ossification are among the common complications of some of these blood diseases. CT examination of the vault and a review of the literature suggest that a blood disorder may well have caused the unusual parietal morphology. Given the nature of these pathological conditions, the Singa individual must have experienced a period of considerable disability. The morphological evidence from the normal bony labyrinth on the left side and from the CT evaluation of the vault is consistent with the interpretation of Singa as a late archaic hominid or an early representative of Homo sapiens drawn from a population which might be directly ancestral to modern humans. Am J Phys Anthropol 107:41–50, 1998. © 1998 Wiley-Liss, Inc.