Abstract
This article examines three key aspects of New Guinea Highlands prehistory, with important implications for regional and global archaeology, including evidence for (1) adaptive flexibility at high altitudes, particularly within montane rainforests and grasslands; (2) plant-food production and cultivation in the tropics; and (3) the emergence of incipient social stratification and how it was transformed by the production and redistribution of material culture, plants, and animals. After synthesizing the archaeological evidence, we propose that social transformations amongst highland groups were intraregionally variable and involved a sequential diversification of subsistence practices that overlapped and persisted through time. Because communities, and their sociotechnical practices, were differently interconnected across the mountains, and at times to the lowlands, coasts, and islands as well, each subregion transformed asymmetrically at different rates and scales through time. The high diversity of highland cultures observed in the early twentieth century by ethnographers is likely to have arisen from these asymmetric processes of growth.