This is an important component of a larger study concerned with the responses of prehistoric hunting-gathering cultures to long term environmental change. The general approach involves comparing cultural systems and their transformations in Middle Europe and the northcentral United States during the late Pleistocene and early Holocene transition from glacial to interglacial conditions. This work is specifically aimed at identifying ecological factors that may help account for similarities and differences in the cultural successions on opposite sides of the Atlantic. Despite broadly similar environmental histories in both regions, important differences are evidenced in, for example, trajectories of climatic amelioration. These, together with differences in human demography, can be seen to have contributed toward shaping divergent cultural adaptations in Europe and North America.