Human adaptive responses to catastrophic landscape disruptions during the Holocene, Numundo, PNG

Prehistoric land use and social activity in West New Britain, PNG, are well documented, although the landscapes – largely shaped by catastrophic volcanic eruptions – in which these took place, and the relationships people had with these landscapes, are poorly understood. We define the evolving landscape at Numundo, from prior to the Witori-Kimbe 2 eruption (W-K2, ca. 3600 BP) to after the Witori-Kimbe 4 eruption (W-K4, ca. 1400 BP), using fossil phytolith and coral evidence at eight archaeological sites to provide environmental evidence of the human responses to periodic catastrophic events. From ca. 5900 to 3600 BP, all the sites were coastal and disturbed. Early disturbance reflected natural forest recovery after W-K1 (ca. 5900 BP), whereas the later landscape was largely shaped by human activity. In contrast, forest regrowth was limited after W-K2 and open environments typical of human activity with a mosaic of regenerating, disturbed and managed vegetation, persisted until W-K3. Environmental recovery from W-K3 and W-K4 (ca. 1700 BP and ca. 1400 BP) differed completely, reflecting severity of the volcanism and the short time between eruptions. The landscape after W-K3 was largely a naturally recovering landscape, in contrast to effective vegetation recovery and significant human exploitation of the landscape – again a mosaic of regenerating, disturbed and managed vegetation – after W-K4. The social history is one in which people evolved increasingly flexible land-use practices, enabling them to re-settle this periodically disrupted landscape, and to take advantage of an increasingly broad range of habitats suitable for cultivation. The human response to this highly dynamic landscape represents a close relationship between social and natural processes, as people became increasingly better at re-settling an unpredictably disrupted landscape; both the social and environmental processes within this landscape become equally influential and instrumental in shaping the effects of the other.