Ecological Contingency Accounts for Earliest Seagoing in the Western Pacific Ocean

ABSTRACT

Seagoing at 1 mya to Flores, and sea gaps of >50 km crossed by 47 kya to Sahul, are evidence of earlier maritime migration in the western Pacific than anywhere else. Current opinion attributes the latter to the influence of anatomically modern human cultural complexity on seagoing technology and practice, together with the impetus of serial resource depression. It is argued here that seagoing was unusually advantaged in the western Pacific by a fortuitous conjunction of the warmest seas with a ready availability of large-diameter bamboo that occurred as natural rafts, and which could also be constructed into rafts large enough to transport viable colonizing groups from island to island across Wallacea to Sahul. The geography of Wallacea allowed migration solely by drifting, and exploratory landscape learning might have produced landfalls on Sahul sooner than is implied by subsistence forcing of mobility. Seagoing by drifting raft was much harder from Sahul to the east because of the virtual absence of large-diameter bamboo and longer distance to fewer or small islands; colonization occurred much later.

Keywords:

• bamboo rafts
• Pleistocene
• seagoing
• warm seas
• western Pacific

ACKNOWLEDGEMENTS

This article began as the Jim Allen Lecture 2008, La Trobe University, and reflected some of my views in a useful debate with Jim Allen and Jim O'Connell. My thanks to Robert DiNapoli and Thomas Leppard for inviting a contribution to the SAA session, and for presenting my paper, and to the referees for their helpful comments.