Waikato samples were pre-treated following standard AMS protocols (UCI KCCAMS, 2011a, b). Following pre-treatment, charcoal (∼2 mm fragments) samples were converted to CO2 in sealed quartz tubes by oxidation at 800°C, using pre-baked CuO in the presence of silver wire to absorb any SOx and NOx produced. Shell (< 3 mm fragments, 35-45 mg) were etched in 0.1M HCl at 80°C to remove ∼45% of the surface. Cleaned shells were then tested for recrystallization by Feigl staining (Friedman, 1959) to ensure either aragonite, or a natural aragonite/calcite distribution was present in the shell (e.g. Nerita sp.). CO2 was collected from shells by reaction with 85% H3PO4. Cryogenically separated CO2 was then reduced to graphite with H2 at 550°C using an iron catalyst. δ 13 C was measured either on a LGR Isotope analyser CCIA-46EP or a Thermos Scientific MAT252 IRMS. Pressed graphite was analysed at the Keck Radiocarbon Dating Laboratory, University of California on a NEC 0.5MV 1.5SDH-2 AMS system (Southon et al., 2004). At ANSTO, after visual inspection for the presence of any powdery, potentially extraneous, calcite deposition shell surfaces were physically cleaned by abrasion of 10-25% of thickness with a Dremel ® tool followed by chemical etching of another 10% with 0.5M HCl for 1-5 minutes under sonication at room temperature (Hua et al., 2001). Feigl

A colonization model is proposed to explain the timing of human occupation in different regions of the arid zone and the reasons for inferred demographic changes through time. A biogeographic approach views changes in human economy and technology against the backdrop of climatic oscillations of the last 40,000 years. This model stands in strong contrast to that of the ‘conservative desert culture’ proposed by Gould, which has become untenable as data from arid zone excavations are increasingly argued to reflect significant changes in human economy, technology and demography through time. The results of regional survey and excavation from the Pilbara and sandy deserts of north‐west Australia, from central Australia, the Flinders Ranges and adjacent dunefields and from semi‐arid Queensland suggest that the occupation of the arid zone from the late Pleistocene on is likely to have been a highly dynamic process. The notion of a stable human adaptation to the diverse landforms and environments of the arid zone finds little support in the archaeological record.

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, we consider the effects of climate systems on past human settlement patterns and inferred demography. We use 5,044 radiocarbon dates from ~1,750 archaeological sites to develop regional timeseries curves for different regions defined in the OZ-INTIMATE compilation as the temperate, tropics, interior and Southern Ocean sectors to explore human-climate relationships in Australia over the last 35,000 years. Correlations undertaken with improved palaeoclimatic data and archaeological records indicate that the regional time-series curves are robust, and can be used as a proxy for human behaviour. However, interrogation of the datasets is essential with artificial peaks and taphonomic over-correction being critical considerations. The time-series curves are interpreted as reflecting population growth, stasis and even decline in phase with terminal Pleistocene/early Holocene climatic fluctuations. This coupling, however, decreases during the last 5,000 years, most likely due to increased population levels, greater territoriality, technological solutions to stress, and social and ideational innovation. Curves from all sectors show exponential population growth over the last 5,000 years. We identify future research priorities, highlighting the paucity of archaeological records across several parts of Australia (<1 dated site/4,000km 2 ), especially around the fringes of the arid zone, and the need for improved taphonomic correction techniques. Finally, we discuss how these time-series curves represent a first-order framework, not dissimilar to global climate models, which researchers can continue to test and refine with local, regional and continental records. KeywordsTime-series analysis, archaeological radiocarbon data, hunter-gatherer behaviour, Aus-INTIMATE, OZ-INTIMATE, human-environment interaction, palaeoenvironment Highlights  Comparison of radiocarbon time-series techniques with other archaeological indices  We demonstrate robust relationship between radiocarbon data and demographic change  Our results suggest past demography was coupled with climate until mid-Holocene  Mid-Holocene social/technological innovation effected a de-coupling of relationship  We provide future directions for Australian archaeological and time-series research 3

The peopling of Sahul (the combined continent of Australia and New Guinea) represents the earliest continental migration and settlement event of solely anatomically modern humans, but its patterns and ecological drivers remain largely conceptual in the current literature. We present an advanced stochastic-ecological model to test the relative support for scenarios describing where and when the first humans entered Sahul, and their most probable routes of early settlement. The model supports a dominant entry via the northwest Sahul Shelf first, potentially followed by a second entry through New Guinea, with initial entry most consistent with 50,000 or 75,000 years ago based on comparison with bias-corrected archaeological map layers. The model’s emergent properties predict that peopling of the entire continent occurred rapidly across all ecological environments within 156–208 human generations (4368–5599 years) and at a plausible rate of 0.71–0.92 km year−1. More broadly, our methods and approaches can readily inform other global migration debates, with results supporting an exit of anatomically modern humans from Africa 63,000–90,000 years ago, and the peopling of Eurasia in as little as 12,000–15,000 years via inland routes.