Paléoenvironnements des îles japonaises lors de la dernière période glaciaire

Abstract

The paper summarizes the paleoenvironments of the last glacial time from a viewpoint of glaciation, permafrost and vegetation. Sea level changes played a critical role on glaciation and human migration to Japanese Islands. Glaciation was limited to the high mountains, and its expansion was much larger in the former stage (MIS 3/4) than in the global glacial maximum (MIS 2). A land bridge between Sakhalin and Hokkaido was important for the migration of paleolithic people from Northern Asia to Japan. Discontinuous permafrost environment with forest tundra and Taiga type conifer forest vegetation in Hokkaido supported the paleolithic hunter-gatherers of big games, developing a microblade culture. Termination of last glacial time caused a drastic environmental change such as a decay of glaciers, permafrost and land bridge. Rapid vegetation change decreased big games and the humans changed their food strategy from a big game hunting to a fishing and a gathering plant resources such as acorns and walnuts. This change created a pottery (Jômon) culture which seems to be brought in Hokkaido from the south between 15,000 ∼ 14,000cal BP. The encounter of paleolithic and southern Jômon peoples in Hokkaido generated a new human group, the northern Jômon people, which might be a origin of the Aïnu, the indigenous people in Japan, especially in Hokkaido.