Why foragers do not become farmers a historical study of changing ecosystem and its effect on a Negrito hunter-gatherer group in the Philippines - Headland, Thomas N. (Ann Arbor, Mich. UMI Dissertation Services, 1986)
An authorized facsimile, made from the microfilm master copy of the original dissertation printed in 1995.
Thesis (Ph.D.)--University of Hawaii, 1986.
Keywords: Agtas -- Social conditions. -- Philippines -- Casiguran (Aurora); Agtas -- Economic conditions. -- Philippines -- Casiguran (Aurora); Biotic communities -- Philippines -- Casiguran (Aurora).