An extraordinary case in human history: Prehistoric hunter-gatherer adaptation to the islands of the Central Ryukyus (Amami and Okinawa archipelagos), Japan

Abstract

The islands of the Central Ryukyus (Amami and Okinawa archipelagos), Japan, were continuously occupied by hunter-gatherers for several thousand years during the Holocene. This occupation would seem to represent a unique example of island settlement by hunter-gatherers. Homo sapiens had expanded into all continents except Antarctica by 10,000 BP, demonstrating high adaptability to various environments, but few islands had been settled by that time. Most islands appear to have been too small to support hunter-gatherer subsistence. Many islands were indeed first colonized by agriculturalists. Some islands located close to large landmasses, having a large surface area, or with reliable sea mammal populations or translocated plants and animals were successfully colonized by hunter-gatherers, but none of these features characterize the prehistoric Central Ryukyu Islands, which were successfully colonized by hunter-gatherers by at least the early–middle Holocene. Furthermore, this colonization was likely accomplished with smaller populations and foraging territories than previously documented for hunter-gatherers. Coral reef resources with nuts (and possibly yams) appear to have played a crucial role in this island colonization. The only similar case to prehistoric Okinawa comes from the Andaman Islands, where hunter-gatherers have occupied small tropical islands for thousands of years. The final part of this paper provides a brief comparison of the Andaman data in light of the results from the Central Ryukyus described here.