Ethan E. Cochrane

The evolution of inequality

Understanding how systems of political and economic inequality evolved from relatively egalitarian origins has long been a focus of anthropological inquiry. Many hypotheses have been suggested to link socio‐ecological features with the rise and spread of inequality, and empirical tests of these hypotheses in prehistoric and extant societies are increasing. In this review, we synthesize several streams of theory relevant to understanding the evolutionary origins, spread, and adaptive significance of inequality. We argue that while inequality may be produced by a variety of localized processes, its evolution is fundamentally dependent on the economic defensibility and transmissibility of wealth. Furthermore, these properties of wealth could become persistent drivers of inequality only following a shift to a more stable climate in the Holocene. We conclude by noting several key areas for future empirical research, emphasizing the need for more analyses of contemporary shifts toward institutionalized inequality as well as prehistoric cases.

Lack of suitable coastal plains likely influenced Lapita (~2800 cal. BP) settlement of Sāmoa: Evidence from south-eastern 'Upolu

Between 3050 and 2700 years ago, humans first colonized the islands of south-west Remote Oceania, a region stretching from Vanuatu to Sāmoa. These colonists created a dense archaeological record of Lapita pottery and other artefacts on island coastlines across the region. There is one striking exception to this pattern: Sāmoa, with only a single Lapita pottery colonization site dating to approximately 2800 years ago. There are two competing explanations for the unique Sāmoan colonization record. First, there was a dense Lapita colonization record, now displaced through sedimentation and coastal subsidence. Second, there were few coastal plains suitable for settlement 2800 years ago resulting in the lack of colonization sites. This article describes the first archaeological and geological research designed to systematically test these explanations. The research focuses on the south-eastern coastal plain of ‘Upolu Island, an area where previous geological research and mid-Holocene sea-level indicators predict the least relative subsidence over the last 3000 years. Auger cores and controlled excavation units sampled the geological sequence and archaeological deposits across 700 m of coast. Sedimentary and dating analyses indicate coastal plain formation beginning 1200 years ago with the earliest archaeological deposits, including plain pottery, lithics, shellfish and vertebrate fauna, dating possibly 700 years later. Microfossil analyses identify burning and forest clearance coincident with the earliest archaeological remains. Compared with other Sāmoan archaeological deposits, the cultural materials and ecofacts represent very low-intensity occupation. These results support the proposal that there were few coastal plains suitable for Lapita pottery–bearing colonists approximately 2800 years ago.

Archaeological and sedimentological data indicate Lapita settlement on a newly formed coastal plain: Tavua Island, Mamanuca Group, Fiji:

The timing and choice of initial settlement location are examined on the small island of Tavua in Fiji’s Mamanuca Group. The mid- to late-Holocene sea-level retreat influenced the island’s coastal landforms through the acceleration of coastal progradation and the production of habitable land. Archaeological, sedimentological, and chronological data are integrated to better understand the island’s settlement and geomorphological history. These datasets are then compared with regional and modeled sea-level curves for Fiji in order to constrain the time period for the onset of coastal regression. The results indicate that Tavua was initially settled around 3000 years ago, within a few centuries of the formation of the coastal plain. Integrating archaeological, sedimentological, and sea-level datasets helps produce a more precise understanding of the relationship between sea-level change and the timing of settlement on small islands in Oceania.

Reassessing the environmental context of the Aitape Skull – The oldest tsunami victim in the world?

There is increasing recognition of the long-lasting effects of tsunamis on human populations. This is particularly notable along tectonically active coastlines with repeated inundations occurring over thousands of years. Given the often high death tolls reported from historical events though it is remarkable that so few human skeletal remains have been found in the numerous palaeotsunami deposits studied to date. The 1929 discovery of the Aitape Skull in northern Papua New Guinea and its inferred late Pleistocene age played an important role in discussions about the origins of humans in Australasia for over 25 years until it was more reliably radiocarbon dated to around 6000 years old. However, no similar attention has been given to reassessing the deposit in which it was found—a coastal mangrove swamp inundated by water from a shallow sea. With the benefit of knowledge gained from studies of the 1998 tsunami in the same area, we conclude that the skull was laid down in a tsunami deposit and as such may represent the oldest known tsunami victim in the world. These findings raise the question of whether other coastal archaeological sites with human skeletal remains would benefit from a re-assessment of their geological context.