Hominids

L— 1 Miocene Mcxjntaina and baslra in Primitive hominids Grasses grazing rnammais... 

Lee-Thoq5, J.A. 1989 Stable carbon isotopes in deep time. The diets of fossil fauna and hominids. Ph.D. Thesis, University of Cape Town, South Africa, 174 pp. 

Ambrose, S.H. 1998 Prospects for stable isotopic analysis of Later Pleistocene hominid diets in West Asia and Europe. In Akazawa, T., Aoki, K. and Bar-Yosef, O., eds.. Neanderthals and Modem Humans in West Asia. New York, Plenum Press 277-289. 

Bocherens, H., Koch, P.L., Mariotti, A., Geraads, D. and Jaeger, J.-J. 1996 Isotopic biogeochemistry ( C, 0) of mammalian enamel from African Pleistocene hominid sites. Palaios 11 306-318. 

C.K., Churcher, C.S., Clark, J.D., Grine, F.E., Shipman, R, Susman, R.L., Turner, A. and Watson, V. 1988 New evidence of early hominids, their culture and environment from Swartkrans Cave. South African Journal of Science 84 828-835. 

Lee-Thorp, J.A. 1989 Stable Carbon Isotopes in Deep Time. The Diets of Fossil Fauna and Hominids. Unpublished Ph.D. dissertation. University of Cape Town. 

Maguire. J.M., Pemberton, D. and Collett, M.H. 1980 The Makapansgat Limeworks grey breccia hominids, hyenas, hystricids or hillwash Palaeontologio Africana 23 75-98. 

Sillen, A. and Morris, A.G. 1996 Diagenesis ofbone from Border cave implications for the age of the Border cave hominids. Journal of Human Evolution 31 499-506. 

Late Pliocene climatic events and hominid evolution. In Grine, F.E., ed.. Evolutionary... 

Bone and tooth enamel from modem animals were collected in 1984 and 1993 from skeletons exposed on the surface in Sibiloi National Park, located on the east shore of Lake Turkana in northern Kenya. In addition to its interest as the site of numerous fossil hominid discoveries, the Turkana area provides an ideal controlled situation for the present study. The park is a circumscribed area surrounded by human pastoral groups and the nondomestic fauna remain to a great extent within its confines. Water sources are limited to the lake, ephemeral streams, a limited number of waterholes, and the plants eaten by the animals. The streams last on the order of days and in dry years do not flow at all. The non-domestic animals from which the bone and enamel were collected likely obtained most of their drinking water from the lake itself Domestic animals entered the park in 1984 during a severe drought. Their drinking water sources may have varied widely. 

Foley, R. 1993 The influence of seasonality on hominid evolution. In Ulejaszek, S.J. and Strickland, S.S., eds.. Seasonality and Human Ecology. Cambridge University Press 17-37. 

Vrba, E.S. 1985 Ecological and adaptive changes associated with early hominid evolution. In Delson, E., eds.. Ancestors The Hard Evidence. New York, Alan K Liss 63-71. 

Speleothems and other secondary carbonate deposits such as tufa, travertines, lake carbonates and vein calcites have the potential to provide valuable information about past climate, hydrogeochemistry, landscape development and hominid evolution during the early Quaternary and Tertiary periods. Electron-spin resonance (Griin 1989, Rink 1997) and disequilibrium methods (Ludwig et al. 1992) have proved to be useful in... 

Zhao J-X, Hu K, Collerson KD, Xu H-K (2001) Thermal ionization mass spectrometry U-series dating of a hominid site near Nanjing, China. Geology 29 27-30... 

Bones and teeth, however, are primary archaeological materials and are common to many archaeological sites. Bones bearing cut marks from stone tools are a clear proxy for human occupation of a site, and in the study of human evolution, hominid remains provide the primary archive material. Hence, many attempts have been made to directly date bones and teeth using the U-series method. Unlike calcite, however, bones and teeth are open systems. Living bone, for example, contains a few parts per billion (ppb) of Uranium, but archaeological bone may contain 1-100 parts per million (ppm) of Uranium, taken up from the burial environment. Implicit in the calculation of a date from °Th/U or Pa/ U is a model for this Uranium uptake, and the reliability of a U-series date is dependent on the validity of this uptake model. 

Chronology is not the only contentious issue debates over the interpretation of morphological and genetic data are as contentious as that of dating. While the anatomical classification of hominids is often problematic and can take a subjective slant, the dating is in theory objective and absolute. The following examples, which have been selected to illustrate these issues are exemplars of the current debate, and cover the major issues noted above specifically from the perspective of U-series dating. 

McDermott et al. (1993) produced EU U-series dates and both EU and LU ESR dates on teeth from the hominid bearing layers of Tabun, Qafzeh and Skhul. Their results suggest both the Neanderthals and Modem Humans from Tabun, Skhul and Qafzeh are much older that previously thought, at around 100 5 ky. Some faunal dates from Skhul were younger at around 43 ky, but were possibly the result of recent accumulation of uranium. Not only do these dates represent some of the earliest modem human skeletal material found anywhere, but the dates of the Neanderthal layers were broadly... 

The criticisms of these results centre on the provenance of the dated faunal material, and the U uptake models employed by Swisher III et al.(1996). In a reply to the paper, Grun and Thome (1997) suggest the river terrace where the material was found had been reworked many times, mixing older with younger material, and that the state of preservation between the hominid remains and the faunal remains was sufficiently different to suggest they had fossilized in a different environment. In addition, they doubt whether the U uptake models employed are appropriate. In the future, direct dating of the hominid remains themselves will address the first problem, a more sophisticated U uptake model would be required to address the second. 

The site of Chaohu, 50 km south of the site of Hexian, yielded a few fragments of hominids classified as archaic H. sapiens which were dated by U-series to 160-200 ky (Chen and Yuan 1988). The site of Dali yielded a reasonably complete cranium which has been assigned to archaic H. sapiens. An EU U-series date of 209 23 ky was... 

The problem here, however, is that the evidence that the skull came from the layer dating between 68-153 ky is inconclusive. Contemporary reports of the appearance, texture and mineralogy of the hominid bearing layer are contradictory, and the possibility that the fossil was from a grave cut into lower layers is not considered. Direct dating of the skull would seem to be the only way to solve these problems. 

The Sierra de Atapuerca in Burgos, Spain, has recently yielded two impressive and important hominid bearing sites, the Gran Dolina, and the Sima de los Huesos. 

Bermndez de Castro JM, Arsuaga JL, Carbonell E, Rosas A, Martinez I, Mosquera M (1997) A hominid from the Lower Pleistocene of Atapuerca, Spain possible ancestor to Neanderthals and modem hnmans. Science 176 1392-1395... 

Bischoff JL, Shamp DD, Arambnm A, Arsuaga JL, Carbonell E, Bermudez de Castro JM (in press) The Sima de Los Hnesos Hominids date to beyond U/Th equilibrium (>350ky) and perhaps to 400-500 ky new radiometric dates. J Arch Sci... 

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