The Environmental Background to Middle Palaeolithic Occupation

The Middle Palaeolithic spans a period of dramatic climatic and ecological change, coinciding broadly with the later stages of the Pleistocene period. The Pleistocene period as a whole was characterized by a long succession of climatic oscillations in which conditions shifted repeatedly between periods of very cold, 'glacial' climate, leading to major expansions of the ice sheets in the northern and southern hemispheres, and intervening 'interglacial' episodes in which the climate returned to conditions broadly similar to those of the present day. In all, at least ten of these glacial/interglacial cycles can now be documented during the past one million years. Exactly what triggered these major changes in world-wide climate is still the subject of lively debate amongst climatic specialists. Most climatologists, however, now subscribe to a version of the Milankovitch 'astronomical hypothesis' in which subtle but significant variations in the pattern of the earth's rotation around the sun, with regular and predictable cycles of around 23,000, 41,000 and 100,000 years, are assumed to have provided the initial stimulus for the majority of documented climatic shifts (see Imbrie et al 1989,1992; Bradley 1985). A clear understanding of these climatic changes and their effects on vegetation patterns, animal populations, annual temperature regimes etc. is an essential prerequisite to any study of the patterns of human occupation by Neanderthals in Europe.

The period which is of most concern to this study is that of the last glacial and inter-glacial cycle which spans the past 130,000 years. Most of the evidence for climatic and environmental conditions over this time range comes from two main sources: first, from studies of the changing oxygen-isotope (180/160) ratios in deep-sea sediments (Fig. 2.1), which provide a fairly direct record of the total quantity of sea water contained in the world's oceans and therefore of the total amount of water locked up on land in the form of ice sheets (see Shackleton 1977, 1987; Bradley 1985); and second, from some of the remarkably long and detailed pollen sequences recently documented from a number of sites in western and southern Europe, such as La Grande Pile and Les Echets in eastern France (Figs 2.6, 2.7), Tenaghi Phiilipon in Greece, Valle di Castiglione in Italy and Padul in southern Spain (Woillard & Mook 1982; de Beaulieu & Reille 1984 etc.). Other important sources of information have come from studies of some of the shorter pollen sequences recorded from sites in northern Europe (Brorup, Amersfoort, Hengelo etc.) (Fig. 2.9), from studies of the changing surface temperatures of the world's oceans based on studies of the varying frequencies of particular planktonic species of marine organisms preserved in sea-bed sediments (Fig. 2.11) and from more general records of climatic and temperature changes derived from studies of Arctic and Antarctic ice cores

Isotope stages->

Isotope stages->

Oxygen Isotope Stages

Figure 2.1 Pattern of oxygen-isotope (180/160) fluctuations in deep-sea sediments over the past 300,000 years, based on studies of five separate ocean cores, with the divisions into major climatic stages indicated. The high points in the curve reflect warm periods with reduced glaciation, while the troughs represent glacial episodes, when the lighter 16 O isotope was selectively removed from the oceans (in the form of water vapour) to form continental ice sheets. Stage 5e represents the peak of the last interglacial. The time scale is derived from the 'orbital forcing' calculations of Martinson et al. 1987.

Figure 2.1 Pattern of oxygen-isotope (180/160) fluctuations in deep-sea sediments over the past 300,000 years, based on studies of five separate ocean cores, with the divisions into major climatic stages indicated. The high points in the curve reflect warm periods with reduced glaciation, while the troughs represent glacial episodes, when the lighter 16 O isotope was selectively removed from the oceans (in the form of water vapour) to form continental ice sheets. Stage 5e represents the peak of the last interglacial. The time scale is derived from the 'orbital forcing' calculations of Martinson et al. 1987.

isotope stages isotope stages

Oxygen Isotope Stages
Figure 2.2 Temperature variations over the past 140,000 years estimated from studies of oxygen-isotope and deuterium ratios in the Voztok ice core from eastern Antarctica. The inferred correlation with deep-sea core isotropic stages is shown at the top of the graph. After Jouzel et al. 1987.

(Figs 2.2, 2.14) (Zagwijn 1990; Behre 1990; Behre & Plicht 1992; Bond et al 1993; Dans-gaard et al 1993; Jouzel et al 1987). Through a combination of these different lines of evidence we can now present a picture of changing climatic and environmental conditions during the later stages of the Pleistocene period with a level of detail and clarity which would have been unimaginable twenty, or even ten, years ago.

In the following sections attention will be focused first on some of the more general patterns of climatic and environmental change which can be documented in western Europe over the course of the later Pleistocene period, and second, on some of the more specific evidence from sites in the region which will provide the main case study throughout the remainder of this book, i.e. the Perigord region and adjacent areas of southwestern France.

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