A unified system of spatial orientation in the Austronesian and non-Austronesian languages of Halmahera

The Austronesian and non-Austronesian languages of Halmahera Island and vicinity share a system of absolute spatial orientation in which the up-down axis is oriented horizontally along the coast. The systems in the individual languages have converged so that it is possible to speak of a single Halmaheran system of orientation whose spatial semantics are independent of language. However, the factors determining the orientation of the upcoast-downcoast axis—which way is up and which is down—have remained elusive. Drawing on a comprehensive survey of the orientation of the upcoast-downcoast axis in Halmahera, we propose an account of orientation in Halmahera which unites both coastal and riverine uses of the up-down axis. We suggest that the orientation of the upcoast direction toward the interior of bays derives from its origin as an upstream directional. An originally non-Austronesian system of riverine orientation has diffused into the Austronesian languages and been adapted to form a pan-Halmaheran directional system.