Fiona Petchey

Language continuity despite population replacement in Remote Oceania.

Recent genomic analyses show that the earliest peoples reaching Remote Oceania—associated with Austronesian-speaking Lapita culture—were almost completely East Asian, without detectable Papuan ancestry. However, Papuan-related genetic ancestry is found across present-day Pacific populations, indicating that peoples from Near Oceania have played a significant, but largely unknown, ancestral role. Here, new genome-wide data from 19 ancient South Pacific individuals provide direct evidence of a so-far undescribed Papuan expansion into Remote Oceania starting ~2,500 yru2009bp, far earlier than previously estimated and supporting a model from historical linguistics. New genome-wide data from 27 contemporary ni-Vanuatu demonstrate a subsequent and almost complete replacement of Lapita-Austronesian by Near Oceanian ancestry. Despite this massive demographic change, incoming Papuan languages did not replace Austronesian languages. Population replacement with language continuity is extremely rare—if not unprecedented—in human history. Our analyses show that rather than one large-scale event, the process was incremental and complex, with repeated migrations and sex-biased admixture with peoples from the Bismarck Archipelago.Genome-wide data from ancient and modern individuals in Remote Oceania indicate population replacement but language continuity over the past 2,500 years. Papuan migrations led to almost complete genetic replacement of in situ East Asian-derived populations, but not replacement of Austronesian languages.

Temporal variability in shell mound formation at Albatross Bay, northern Australia

We report the results of 212 radiocarbon determinations from the archaeological excavation of 70 shell mound deposits in the Wathayn region of Albatross Bay, Australia. This is an intensive study of a closely co-located group of mounds within a geographically restricted area in a wider region where many more shell mounds have been reported. Valves from the bivalve Tegillarca granosa (Linnaeus, 1758) were dated. The dates obtained are used to calculate rates of accumulation for the shell mound deposits. These demonstrate highly variable rates of accumulation both within and between mounds. We assess these results in relation to likely mechanisms of shell deposition and show that rates of deposition are affected by time-dependent processes both during the accumulation of shell deposits and during their subsequent deformation. This complicates the interpretation of the rates at which shell mound deposits appear to have accumulated. At Wathayn, there is little temporal or spatial consistency in the rates at which mounds accumulated. Comparisons between the Wathayn results and those obtained from shell deposits elsewhere, both in the wider Albatross Bay region and worldwide, suggest the need for caution when deriving behavioural inferences from shell mound deposition rates, and the need for more comprehensive sampling of individual mounds and groups of mounds.

Postcards from the outside: European-contact rock art imagery and occupation on the southern Arnhem Land plateau, Jawoyn lands

The archaeomorphological study of Nawarla Gabarnmang in Australias Northern Territory challenges us to think in new ways about how Aboriginal people interacted with their surroundings; here a site of everyday engagement was a place of construction that retains material traces of past engagements. At Nawarla Garbarnmang, we show through archaeomorphological research how the changing physical layout of a site can be cross-examined against the impacts of human engagements through time. While the scope and scale of activities involved the anthropogenic removal over tens of thousands of years of rock pillars below the caves roof, other practices came and went over time, the complex sequence of rock art conventions being an apt example. These artistic transformations, much like the era of pillar clearances, are a clear example of changing cultural practices in a part of Australia where some 50,000 years of human occupation can be shown.The Arnhem Land plateau in northern Australia contains a particularly rich rock art assemblage. The area has a small number of large rockshelters with numerous and extensive suites of superimposed motifs (c. 2 per cent of 630 recorded shelters have >200 images). Studies of the rock art of Arnhem Land have primarily been concerned with attempting to understand the age of the art, with particular interest on the Pleistocene to mid-Holocene periods (Chaloupka 1977, 1984, 1985, 1993; Chippindale and Taçon 1993; Haskovec 1992; Lewis 1998; Taçon and Chippindale 1994). Most of these efforts have largely relied on interpretations of styles and their respective patterns of superimposition. Taçon (e.g. 1987, 1989a, 1989b, 1992) has written extensively on X-ray rock art from the northern perimeter of the plateau, and his work on ‘recent’ period art remains the most important study on this subject. The production of X-ray art has also been shown to have been popular during the European-contact period of the past 200 years or so (Chaloupka 1993; May et al. 2010; Wesley 2013). The most detailed study of rock art in the late Holocene period is the extensive radiocarbon dating of beeswax figures by Nelson et al. (2000), most of which fall within the past 500 years (but see Bednarik 2001).This chapter explores [the] incongruity in the distribution of Western-contact motifs contrasting northwestern and southwestern Arnhem Land in relation to the rich corpus of other kinds of rock art on the plateau. We stress from the onset that while images of ‘Western-contact art’ derive from a wide variety of responses to outsider influences, and include imagery that employs conventions akin and often indistinguishable to those of the pre–Western contact period, in this chapter we restrict our discussion to images of introduced objects and demonstrably foreign npeoples.