Particular geographic features of the Mediterranean Levant underlie the subsistence patterns and social structures reconstructed from the archaeological remains of Epi-Paleolithic groups. The Kebaran, Geometric Kebaran, and Mushabian complexes are defined by technotypological features that reflect the distributions of social units. Radiocarbon dating and paleoclimatic data permit us to trace particular groups who, facing environmental fluctuations, made crucial changes in subsistence strategies, which, in the southern Levant, led to sedentism in base camps on the ecotone of the Mediterranean woodland-parkland and the Irano-Turanian steppe. The establishment of Early Natufian sedentary communities led to a regional change in settlement pattern. The relatively cold and dry climate of the eleventh millennium B.P. forced Negev groups into a special arid adpatation. The early Holocene onset of wetter and warmer conditions favored the earliest Neolithic (PPNA) development of village life based on the cultivation of barley and legumes, gathering of wild seeds and fruits and continued hunting.