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

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 Tegillarcca granosa 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

An Assessment and archaeological application of cortex measurement in lithic assemblages

We describe an experimental test and archaeological application of the solid geometry method for the interpretation of cortical surface area in lithic assemblages proposed by Dibble et al. (2005). Experimental results support the method's accuracy while archaeological application to assemblages from western New South Wales, Australia suggests a repeated pattern of the selective removal of artifacts away from their location of manufacture. These findings shed light on the role curation and mobility play in the use and eventual discard of those artifact classes for which conventional measures of curation are not applicable. The results raise new questions about Aboriginal technological organization and land use, while simultaneously highlighting the complex relationship between past human behavior and archaeological assemblage content.14 page(s

Context and Complexity on the Arid Margins of Australia: Assessing Human Responses to an Unpredictable Environment

26 page(s

The Wathayn study area on the north bank of the Embley River, showing the locations of the shell mounds.

<p>Contours derived from airborne LiDAR data indicate the topography. Both LiDAR and air photography data provided courtesy of RioTintoAlcan (Weipa) Pty Ltd. (Modified from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183863#pone.0183863.ref030" target="_blank">30</a>] under a CC BY license, with permission from Elsevier, original copyright 2016).</p

Large shell mound in the vicinity of the study area.

<p>Predominantly composed of the shells of the bivalve <i>Tegillarca granosa</i> (syn. <i>Anadara granosa</i> (Linnaeus 1758)), some mounds attain heights of ten metres or more. (Source of image: PCF. The individual pictured gave written informed consent (as outlined in PLOS consent form) to publish his image).</p

Conventional radiocarbon age determinations, calibrated mean age ± 1σ and rates of accumulation, calculated using depth below surface, of the Wathayn shell mounds.

<p>Conventional radiocarbon age determinations, calibrated mean age ± 1σ and rates of accumulation, calculated using depth below surface, of the Wathayn shell mounds.</p

Location map of the study area.

<p>Albatross Bay is a shallow, semi-circular embayment on the northwestern coast of Cape York Peninsula in far north Queensland, Australia, that opens into the Gulf of Carpentaria. The study area of Wathayn is situated on the northern side of the Embley River, one of four estuaries draining into Albatross Bay. The map also shows the location of other places mentioned in the text. (Modified from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183863#pone.0183863.ref030" target="_blank">30</a>] under a CC BY license, with permission from Elsevier, original copyright 2016).</p