The region containing the sites of interest in this chapter stretches from the
Caspian Sea in the west to the Pamirs and Tian Shan in the east. This is a
vast area with highly variable natural conditions. Different sections of this
region have experienced different geological and environmental histories.
The arid plains and mountains lying in the west, between the Caspian Sea
and the Aral Sea, are of minor significance for this chapter, because no early
Upper Paleolithic sites—nor any later Upper Paleolithic sites, for that
matter—have as yet been discovered there. Much more important is eastern
central Asia, where two great mountain systems—the Pamirs and Tian
Shan—form a single mountainous country. A considerable part of this coun-
try lies above 5000 m in elevation, and the highest ridges exceed 7000 m.
There are also many depressions and large valleys where sedimentary
deposits accumulated during the Pleistocene. Among the dozens of sealed
Paleolithic sites known in the region, there are several that can be more or
less confidently assigned to the late Middle and/or early Upper Paleolithic
( figure 11.1 ).

According to a widely held view, the climate of the Pamirs/Tian Shan area
during the Late Cenozoic became increasingly arid, which led to significant
changes in faunal and floral communities. Palynological data indicate that
each succeeding stage of the Cenozoic was characterized by decreasing bio-
logical productivity and diversity (Pakhomov 1973), so that by the late Pleis-
tocene, no more than ten or fifteen floral genera have been reported (even
for the most humid periods), whereas in the middle Pleistocene, the num-
ber of genera reached twenty-six (Nikonov et al. 1989). A great deal of con-
troversy exists regarding the correlation of mountain glaciations with cli-

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