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C B Stringer

Publications and source records attributed to C B Stringer.

6 recordsLinked to original sources

Reconstructing recent human evolution.

The two most distinct models of recent human evolution, the multiregional and the recent African origin models, have different retrodictions concerning specific archaic-recent population relationships. The former model infers multiple regional archaic-modern connections and the ancient establishment of regional characteristics, whereas the latter model implies only an African archaic-all modern relationship, with recent (late Pleistocene) development of regionality. In this paper, four late archaic groups from Europe, southwest Asia, Africa and East Asia are compared with various fossil and recent Homo sapiens crania or cranial samples. The results of Penrose shape comparisons narrowly favour a late archaic African-modern special relationship over an East Asian-modern one, with European and southwest Asian Neanderthal groups much more distant. No specific archaic-recent regional relationships are indicated in the shape analyses, nor in separate examinations of patterns of regionality, which indicate a recent origin for present day regionality. The Skhul-Qafzeh sample provides an excellent shape intermediate between the archaic and recent samples.

Animals

ESR dating evidence for early modern humans at Border Cave in South Africa.

The archaeological and hominid site of Border Cave (KwaZulu, South Africa) has a stratigraphic sequence covering the Middle and Later Stone Ages (MSA and LSA). It has been proposed that four hominid specimens recovered there (BC1 and BC2 of uncertain provenance, and BC3 and BC5 recovered from MSA layers) represent very early examples of anatomically modern humans, supporting an early late-Pleistocene appearance of modern Homo sapiens in Africa. This early appearance, however, has been questioned, largely because of doubts about the stratigraphic positions associated with the specimens and because of the lack of a reliable chronology for the stratigraphic sequence. We now report on the first comprehensive radiometric dating analysis of Border Cave, using electron spin resonance (ESR) on teeth within sediment layers. BC3 is likely to be approximately 70-80 kyr old, and BC5, 50-65 kyr old. BC1 and BC2 are almost certainly less than 90 kyr old. These results, although younger than some age estimates, support the early occurrence of anatomically modern humans at Border Cave. In addition, our results suggest that the Howiesons Poort lithic industry (approximately 45-75 kyr) and the MSA-LSA transition (approximately 35 kyr) are younger than often believed.

Animals

The emergence of modern humans.

The theory that all humans are descended from a recent African ancestor was promoted by geneticists who study living populations. The fossil record provides independent support for this model.

Africa, Eastern

ESR dates for the hominid burial site of Es Skhul in Israel.

The Middle East has been critical to our understanding of recent human evolution ever since the recovery of Neanderthal and early anatomically modern fossils from the caves of Tabun and Skhul (Mount Carmel) over 50 years ago. It was generally believed, on archaeological and morphological grounds, that middle eastern Neanderthals (such as those from Tabun, Amud and Kebara) probably dated from more than 50,000 years ago, whereas the earliest anatomically modern specimens (from Skhul and Qafzeh) probably dated from about 40,000 years. Recent thermoluminescence and electron spin resonance (ESR) determinations, however, have supported biostratigraphy in dating the Qafzeh deposits to an earlier part of the late Pleistocene, probably more than 90,000 years ago. These dates have been questioned on unspecified technical grounds, and it has also been argued that they create explanatory problems by separating the morphologically similar Qafzeh and Skhul samples by some 50,000 years, thus implying a long-term coexistence of early modern humans and Neanderthals in the area. Here we report the first radiometric dating analysis for Skhul, using ESR on bovine teeth from the hominid burial levels. Early uptake and linear uptake ages average 81 +/- 15 and 101 +/- 12 kyr respectively. These analyses suggest that the Skhul and Qafzeh samples are of a similar age and therefore it is possible that the presence of early modern humans in the area was episodic, rather than long-term during the early late Pleistocene.

Animals