PALEODEMOGRAPHY OF THE ATAPUERCA-SH MIDDLE PLEISTOCENE HOMINID SAMPLE

We report here on the palaeodemographic analysis of the hominid sample recovered to date from the Sima de los Huesos (SH) Middle Pleistocene cave site in the Sierra de Atapuerca (Burgos, Spain). The analysis of the mandibular, maxillary, and dental remains has made it possible to estimate that a minimum of 32 individuals, who probably belonged to t he same biological population, are represented in the current SH human hypodigm. The remains of nine individuals are assigned to males, and nine to females, suggesting that a 1:1 sex ratio characterizes this ho minid sample. The survivorship curve shows a low representation of inf ants and children, a high mortality among the adolescents and prime-ag e adults, and a low older adult mortality. Longevity was probably no g reater than 40 years. This mortality pattern (adolescents and adults), which in some aspects resembles that observed in Neandertals, is quit e different from those reported for recent foraging human groups. The adult age-at-death distribution of the SH hominid sample appears to be neither the consequence of underaging the older adults, nor of differ ential preservation or of the recognition of skeletal remains. Thus if we accept that they had a life history pattern similar to that of mod ern humans there would appear to be a clear contradiction between the demographic distribution and the demographic viability of the populati on represented by the SH hominid fossils. The possible representationa l bias of the SH hominid sample, as well as some aspects of the reprod uctive biology of the Pleistocene populations are also discussed. (C) 1997 Academic Press Limited.