Stone age bedding by the Sea of Galilee.

E vidence by Nadel et al. (1), in a recent issue of PNAS, of the world’s oldest bedding at the site of Ohalo II on the edge of the Sea of Galilee is an example of the serendipitous nature of archaeological discovery. During the 1980s and 1990s, drought and pumping of water for domestic and agricultural needs resulted in a serious drop of water level. The falling water level exposed 2,000-year-old boats and the archaeological site Ohalo II, dated to 23,000 years ago (Fig. 1). The site is noteworthy for three reasons. First, it has preserved a wide range of plant material and organic traces of huts or shelters in which people lived. Second, the site was occupied toward the end of what must have been one of the most severe climatic episodes in human history. Finally, direct evidence of bedding and, consequently, of the layout of the domestic space was recovered. Before the Neolithic period (after 11,000 years ago), there is little direct evidence of the human use of plant resources, and information about adaptations and ways of life depend largely on stone artifacts and faunal remains found in archaeological sites. Nadel et al. (1) mention the rare earlier occurrences of normally perishable material and thereby highlight the extraordinary circumstances of the Ohalo discovery where rapid burial by a layer of sand and water sealed the site from disturbance. The burial must have been essentially instantaneous because wave action, exposure to wind and rain, and so on would have dispersed and degraded the plant material and outlines of the huts. Chance good luck preserved a unique site, raising the question of how many more such sites lie submerged around the lake. The Sea of Galilee itself was newly formed when Ohalo was settled and probably attracted many bands of hunters and fishers. Throughout the Pleistocene, the Levantine Rift, a structural depression extending from the Red Sea to the mountains of Southern Anatolia, saw essentially continuous human occupation. The central part of this rift is the Dead Sea Valley, in which, during the final glacial period, Lake Lisan stretched from south of the Dead Sea northward to the Sea of Galilee. Tectonic activity at the end of the last glacial period created the Sea of Galilee (2) as well as the deep northern Dead Sea basin and left the two separated by the Jordan River (see figure 5.90 of ref. 3 and figure 15 of ref. 4). Another remarkable factor is that, according to the radiocarbon dates, the site was occupied during the Last Glacial Maximum (LGM), when climate indicators such as pollen and isotopic composition of speleothems, as well as a greatly lowered permanent snow line, indicate that the Near East was cold and arid (5, 6). Botanists have inferred that many plant species, including trees, were vacant from much of the landscape and were present only in small refugia where water resources and enhanced solar warming due to topography and aspect created favorable conditions. Under these late glacial conditions, human populations and the game on which they subsisted were restricted to the most favorable locales. Ohalo was in an environment with abundant terrestrial and aquatic resources in a broader landscape that was relatively impoverished. Plant remains indicate spring and fall harvest, and birds, both migratory and local, as well as fish, could be harvested in all seasons. There seems little reason to doubt that year-round use of the site would have been possible (2). Nevertheless, it is hard to reconcile the apparent abundance of food resources with the apparent very short-term occupation of the huts (7). One of the major questions about the late Pleistocene and early Holocene in the Levant is the climate and the resources that could be used by humans.