Middle Plesitocene Hominins

The premodern humans of the Middle Pleistocene i.e., after 780,000 mya, usually succeeded H. erectus.  After the riches offered by the Sterkfontcin Valley and Makapansgat, southern Africa's Middle Pleistocene fossil record is comparatively poor, though by no means insignificant. Hominid remains are known from four sites south of the Zambezi and from Kabwe and Mumbwa in Zambia (Rightmire 1984). The Kabwe (Broken Hill) cranium was recovered from cave fill deposits that also produced fragments of several other individuals and doubtfully asso­ciated Achculcan/Sangoan artefacts, faunal evidence suggests a late Middle Pleistocene date is likely (Klein 1973). Much more certainly associated with Acheulean artefacts are a juvenile mandible from Cave of Hearths (Tobias 1971) and an incomplete cranium and unassociated mandibular fragment from Elandsfontein (Drennan 1953). At both sites the artefacts suggest a mid-Quaternary age (0.5-0.2 mya, supported at Elandsfontein by Klein's (1988) faunal analyses.

Another Middle Pleistocene hominin from a carnivore-accumulated assemblage at Florisbad, this partial cranium was found in a spring eye that predates most, but not all, of the MSA activity at the same site. Recent ESR determinations give it a weighted mean age of 259 ± 35,000 BP (Grun et al. 1996). Finally, Gladysvale has produced some fragmentary Homo remains that appear to be of Middle Pleistocene age (Tobias 20001. This is not a large sample from which to draw conclusions, but it can be ex­panded by reference to other specimens from elsewhere in Africa and beyond. The most striking thing about all four fossils is their archaic appearance. Kabwe, in particular, has a low skull and massive brow ridges. Nevertheless, its cranial capacity (1280 cm³), like that of the Elandsfontein skull (1200-1250 cm³), shows significant advance over earlier ergaster grade fossils. This is reinforced by sev­eral morphological features of the Kabwe and Florisbad crania. All can be placed within Homo sapiens as a distinctly archaic and African subspecies, H. sapiens rhodesiensis (Rightmire 1976).

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