Christopher Clarkson | The University of Queensland, Australia (original) (raw)

Books by Christopher Clarkson

The Oxford Handbook of the Archaeology of Indigenous Australia and New Guinea, 2022

Mainland Australia was connected to New Guinea and Tasmania at various times throughout the Pleis... more Mainland Australia was connected to New Guinea and Tasmania at various times throughout the Pleistocene and formed the supercontinent of Sahul. Sahul contains some of the earliest known archaeological evidence for Homo sapiens outside of Africa, with a growing record of early complex social, technological, and artistic life. Here we present an overview of the oldest known sites in Australia along with key evidence pertaining to the dynamic cultures of early Aboriginal peoples. We review debates surrounding the age of rst settlement and present evidence for the earliest technology, economy, and symbolism in Australia, emphasizing maritime skills, a large founding population size, novel technology, and adaptation to a wide range of environments.

The question "How common is convergence?" remains unanswered and may be unanswerable. Our example... more The question "How common is convergence?" remains unanswered and may be unanswerable. Our examples indicate that even the minimum detectable levels of convergence are often high, and we conclude that at all levels convergence has been greatly underestimated.-Moore and Willmer (1997: 1) Convergence in stone-tool technology, much like in biology, was likely a recurring phenomenon throughout the last three million years of human evolution, where functional and economic constraints exerted strong selection on tool size and form as well as other characteristics of technological systems. Some of the best examples of convergent stone working include the Nubian Levallois method (Will, Mackay, and Phillips 2015); overshot flaking of Solutrean and Palaeoindian points (Eren, Patten, O'Brien, and Meltzer 2013b; chapter 1, this volume); fluting on Palaeoindian and southern Arabian points (Crassard 2009); ground-edge axe technology in Pleistocene Australasia, Japan, and multiple Neolithic societies (Clarkson et al. 2015; Hiscock, O'Connor, Balme, and Maloney 2016; Takashi 2012); pressure blade technology in Mesoamerica and Eurasia (Crabtree 1968; Pelegrin 2003); and punch flaking on Danish and Polynesian adzes (Shipton, Weisler, Jacomb, Clarkson, and Walter 2016; Stueber 2010). Likewise, countless more or less identical tool forms appear around the globe in different times and places as the product of seemingly independent invention to meet local needs, be they burins, end scrapers , blades, or discoidal cores. The question is not whether convergence took place, but whether it was common and widespread or took place only under exceptional circumstances. There are many reasons for thinking it was the former, but providing compelling evidence for independent origins without contact between regions, as well as deriving robust evolutionary explanations, are ongoing challenges for archeology. Multiple lines of evidence are required to test such arguments, and these might typically involve experimentation, modeling selective environments, and developing appropriate means of analyzing archeological and environmental data to determine the context of autochthonous development rather than cultural transmission from other populations.

Nature Communications, 2020

India is located at a critical geographic crossroads for understanding the dispersal of Homo sapi... more India is located at a critical geographic crossroads for understanding the dispersal of Homo sapiens out of Africa and into Asia and Oceania. Here we report evidence for long-term human occupation, spanning the last ~80 thousand years, at the site of Dhaba in the Middle Son River Valley of Central India. An unchanging stone tool industry is found at Dhaba
spanning the Toba eruption of ~74 ka (i.e., the Youngest Toba Tuff, YTT) bracketed between ages of 79.6 ± 3.2 and 65.2 ± 3.1 ka, with the introduction of microlithic technology ~48 ka. The lithic industry from Dhaba strongly resembles stone tool assemblages from the African Middle Stone Age (MSA) and Arabia, and the earliest artefacts from Australia, suggesting that it is likely the product of Homo sapiens as they dispersed eastward out of Africa.

Jerimalai is a rock shelter in East Timor with cultural remains dated to 42,000 years ago, making... more Jerimalai is a rock shelter in East Timor with cultural remains dated to 42,000 years ago, making it one of the oldest known sites of modern human activity in island Southeast Asia. It has special global significance for its record of early pelagic fishing and ancient shell fish hooks. It is also of regional significance for its early occupation and comparatively large assemblage of Pleistocene stone artefacts. Three major findings arise from our study of the stone artefacts. First, there is little change in lithic technology over the 42,000 year sequence, with the most noticeable change being the addition of new artefact types and raw materials in the mid-Holocene. Second, the assemblage is dominated by small chert cores and implements rather than pebble tools and choppers, a pattern we argue is common in island SE Asian sites as opposed to mainland SE Asian sites. Third, the Jerimalai assemblage bears a striking resemblance to the assemblage from Liang Bua, argued by the Liang Bua excavation team to be associated with Homo floresiensis. We argue that the near proximity of these two islands along the Indonesian Island chain (c.100 km apart), the long antiquity of modern human occupation in the region (as documented at Jerimalai), and the strong resemblance of distinctive flake stone technologies seen at both sites, raises the intriguing possibility that both the Liang Bua and Jerimalai assemblages were created by modern humans.

This monograph takes a new look at various aspects of stone artefact analysis that reveal importa... more This monograph takes a new look at various aspects of stone artefact analysis that reveal important and exciting new information about the past, and in particular Australian perspectives on lithics. The ten papers making up this volume tackle a number of issues that have long been at the heart of archaeology’s problematic relationship with stone artefacts, including our understanding of the dynamic nature of past stoneworking practices, the utility of traditional classificatory schemes, and ways to unlock the vast amount of information about the strategic role of lithic technology that resides in stone artefact assemblages. The dominant theme of this monograph is the pursuit of new ways of characterising the effects of manufacturing and susbsistence behaviour on stone artefact assemblages. CONTENTS: 1. Introduction: Casting New Light on Old Stones (Chris Clarkson and Lara Lamb); 2. Measuring Artefact Reduction - An Examination of Kuhn’s Geometric Index of Reduction (Peter Hiscock and Chris Clarkson); 3. Tenuous Types: Scraper Reduction Continuums in the Eastern Victoria River Region, Northern Territory (Chris Clarkson); 4. Backed and Forth: An Exploration of Variation in Retouched Implement Production on the South Molle Island Quarry, Central Queensland (Lara Lamb); 5. Reduction Continuums and Tool Use (Peter Hiscock and Val Attenbrow); 6. Abrupt Terminations and Stone Artefact Reduction Potential (Oliver Macgregor); 7. Stone Artefact Assemblage Variability in Late Holocene Contexts in Western New South Wales: Burkes Cave, Stud Creek and Fowlers Gap (Justin Shiner, Simon Holdaway, Harry Allen and Patricia Fanning); 8. Stone artefact reduction, mobility, and arid zone settlement models: a case study from Puritjarra rockshelter, Central Australia (W. Boone Law); 9. Informal Movements: Changing Mobility Patterns at Ngarrabullgan, Cape York Australia (Alex Mackay); 10. The Reduction Thesis and its Discontents: Overview of the Volume (Michael J. Shott).

This monograph reports on 15,000 years of technological and social change in a region of northern... more This monograph reports on 15,000 years of technological and social change in a region of northern Australia located on the edge of the semi-arid zone amidst mesas, deep gorges and dry basalt plains. It is a region best known for its spectacular rock art, and more particularly the striped anthropomorphic
figures known as the ‘Lightning Brothers’ which decorate the walls of some rockshelters in the south of the traditional lands of the Wardaman people. The region is also known for its rich archaeological record, and has been the subject of intensive archaeological study since Davidson’s research there in
the 1930s. This monograph employs foraging theory and recent thinking about the strategic organisation of lithic technology to explore changing settlement and subsistence practices in this region since the end of the Last Glacial
Maximum. Applying this approach to the explanation of assemblage variability in Wardaman Country offers new insights into the possible reasons for technological and social change in this region over the last 15,000 years.

The ideas about technological responses to different foraging practices developed in this monograph are tested against assemblage data from four rockshelters located in different parts of Wardaman Country. The results suggest that major changes in lithic technology and land use took place in reaction to increased subsistence risk brought on by declines in the abundance and predictability of resources.
These declines may have been triggered by the onset of ENSO-driven climatic variability after 5,000 BP, which appears to have reached its greatest severity in northern Australia between c. 3,500 and 2,000 BP. This study has important implications for our understanding of northern Australian prehistory, including the potential causes of broadly similar technological changes across large parts of the top end and the timing of increased inter-regional contact and the spread of new technologies. It also illustrates the importance of tracking continuity in manufacturing traditions as a means of understanding the kinds of social processes that underlie regional technological changes.

Papers by Christopher Clarkson

Scientific Reports, 2022

Stone tools are a manifestation of the complex cognitive and dexterous skills of our hominin ance... more Stone tools are a manifestation of the complex cognitive and dexterous skills of our hominin ancestors. As such, much research has been devoted to understanding the skill requirements of individual lithic technologies. Yet, comparing skill across different technologies, and thus across the vast timespan of the Palaeolithic, is an elusive goal. We seek to quantify a series of commensurable metrics of knapping skill across four different lithic technologies (discoids, handaxes, Levallois, and prismatic blades). To compare the requisite dexterity, coordination, and care involved in each technology, we analysed video footage and lithic material from a series of replicative knapping experiments to quantify deliberation (strike time), precision (platform area), intricacy (flake size relative to core size), and success (relative blank length). According to these four metrics, discoidal knapping appears to be easiest among the sample. Levallois knapping involved an intricate reduction sequence, but did not require as much motor control as handaxes and especially prismatic blades. Compared with the other Palaeolithic technologies, we conclude that prismatic blade knapping is set apart by being a skill intensive means of producing numerous standardised elongate end-products.

Journal of Archaeological Science: Reports, 2021

The functional study of ground stone artefacts and the analysis of charred plant remains together... more The functional study of ground stone artefacts and the analysis of charred plant remains together demonstrate that plant foods played a significant role in the diets of Aboriginal Australians through all occupation phases at the Pleistocene-aged archaeological site of Madjedbebe. Here we report studies of three sandstone grinding stones from the Holocene levels of the site, one associated with a radiocarbon age of 690 cal. BP, and the others with an age of 8320 cal. BP. The functional analyses involved technological studies combined with brightfield microscopy, starch grain analysis, biochemical testing and gas chromatography-mass spectrometry (GC-MS). All three tools had usewear consistent with plant processing, with two having abrasive smoothing and polish characteristics typical of seed-grinding. Significant quantities of starch were recovered from each artefact and demonstrate the early Holocene processing of waterlily (Nymphaea violacea) and possibly kapok bush root (Cochlospermum fraseri), cheeky yam (Amorphopallus galbra) and long yam (Dioscorea transversa). In addition to starchy plant foods, one of the tools was used for processing animal tissue, as indicated by biochemical testing and GC-MS analysis, inferring a multi-functional use.

Australian Archaeology, 2018

Quaternary Science Reviews, 2019

The pace of research undertaken in Sunda (Southeast Asia) through to Sahul (Greater Australia) ha... more The pace of research undertaken in Sunda (Southeast Asia) through to Sahul (Greater Australia) has increased exponentially over the last three decades, resulting in spectacular discoveries ranging from new hominin species, significant extension to the age for first human occupation in the region, as well as the identification of what is currently the oldest known rock art in the world. These breakthroughs cast the archaeological record of complexity in Sunda, Sahul, and Wallacea in an entirely different light to that of several decades ago, placing it on an equal footingto that of Africa, Asia, and Europe. The archaeological record of these regions now points to rich and diverse early modern human (Homo sapien) societies engaged in complex symbolic and technological behaviours demonstrating capacities for innovation and self-expression found in all modern human groups now around the globe. Here we provide a comprehensive review of all Pleistocene symbolic evidence reported for Sahul, Sunda, and Wallacea to date. We explore how recent findings have changed our perceptions of the first modern human colonists and our understanding of the origins and development of the rich and diverse cultures that arose in each region through time.

Journal of Archaeogical Science: Reports, 2020

Numerous plant seeds (the caryopsis or achene) from a wide variety of genera were traditionally g... more Numerous plant seeds (the caryopsis or achene) from a wide variety of genera were traditionally ground for food by hunter-gatherer peoples, including over 200 varieties by Aboriginal Australians. In Australia, these seeds varied greatly in size, shape and hardness. Except for a broad distinction being made between grass and tree seeds, differences in the morphological and other characteristics of seedsin particular their performance in seed-grindingare rarely documented. A recent experimental examination of the efficiency of millstones using commercial proxies for difficult to obtain Australian native seeds has shown significant differences in workability and output of different types of seeds. This paper tests predictions as to whether the grinding characteristics of a number of widely used native seeds also vary significantly, the implications this has for the selection, treatment and use of seeds by Aboriginal people in Australia and elsewhere, and generates quantitative data which can supplement and explicate other experimental research. It also makes a preliminary assessment of whether domesticated seeds can provide useful grinding analogues for unavailable native seeds. Our findings have broad relevance for an understanding of prehistoric seed-grinding and species selection in Australia and other parts of the world.

Nature Communications, 2020

There is little evidence for the role of plant foods in the dispersal of early modern humans into... more There is little evidence for the role of plant foods in the dispersal of early modern humans into new habitats globally. Researchers have hypothesised that early movements of human populations through Island Southeast Asia and into Sahul were driven by the lure of highcalorie, low-handling-cost foods, and that the use of plant foods requiring processing was not common in Sahul until the Holocene. Here we present the analysis of charred plant food remains from Madjedbebe rockshelter in northern Australia, dated to between 65 kya and 53 kya. We demonstrate that Australia's earliest known human population exploited a range of plant foods, including those requiring processing. Our finds predate existing evidence for such subsistence practices in Sahul by at least 23ky. These results suggest that dietary breadth underpinned the success of early modern human populations in this region, with the expenditure of labour on the processing of plants guaranteeing reliable access to nutrients in new environments.

Journal of Human Genetics, 2020

New Guineans represent one of the oldest locally continuous populations outside Africa, harboring... more New Guineans represent one of the oldest locally continuous populations outside Africa, harboring among the greatest linguistic and genetic diversity on the planet. Archeological and genetic evidence suggest that their ancestors reached Sahul (present day New Guinea and Australia) by at least 55,000 years ago (kya). However, little is known about this early settlement phase or subsequent dispersal and population structuring over the subsequent period of time. Here we report 379 complete Papuan mitochondrial genomes from across Papua New Guinea, which allow us to reconstruct the phylogenetic and phylogeographic history of northern Sahul. Our results support the arrival of two groups of settlers in Sahul within the same broad time window (50-65 kya), each carrying a different set of maternal lineages and settling Northern and Southern Sahul separately. Strong geographic structure in northern Sahul remains visible today, indicating limited dispersal over time despite major climatic, cultural, and historical changes. However, following a period of isolation lasting nearly 20 ky after initial settlement, environmental changes postdating the Last Glacial Maximum stimulated diversification of mtDNA lineages and greater interactions within and beyond Northern Sahul, to Southern Sahul, Wallacea and beyond. Later, in the Holocene, populations from New Guinea, in contrast to those of Australia, participated in early interactions with incoming Asian populations from Island Southeast Asia and continuing into Oceania.

Beyond Stones and More Stones, 2017

Quaternary Science Reviews, 2019

We present Bayesian modelling on a long sequence of radiocarbon ages from the archaeological site... more We present Bayesian modelling on a long sequence of radiocarbon ages from the archaeological site of Nawarla Gabarnmang, central Arnhem Land plateau, northern Australia. A horizon of wind-borne sediments containing flaked stone artefacts and charcoal commencing >45,610 cal BP (the young end of the modelled boundary age range, which extends beyond the limit of the calibration curve), with a median modelled age of 48,500 cal BP, signals the onset of aeolian mobilisation of fine sands and silts across the landscape, and re-deposition within the site at a time synchronous with the first evidence of people. This earliest cultural horizon (Stratigraphic Unit 4) contains 509 stone artefacts, and is marked by a contemporaneous sedimentary break, from underlying culturally sterile sediments consisting of disintegrating roof-fall and in situ sandstone and quartzite to overlying culturally-rich wind-blown sand. The new radiocarbon ages and wind-blown sediments together provide evidence for the commencement of noticeable landscape burning on the Arnhem Land plateau c. 48,500 cal BP, suggesting an intensification of landscape management practices at the summit of the Arnhem Land plateau some 10,000 e15,000 years after the lowest dense band of artefacts (Phase 2) at Madjedbebe on the floodplains 90 km to the north. These results have ramifications for the structure and timing of the spread of people across Australia, and the extinction of megafauna in Sahul.

EXARC, 2020

Hafted stone tools commonly figure in Australian archaeology but hafting traces and manufacture p... more Hafted stone tools commonly figure in Australian archaeology but hafting traces and manufacture processes are infrequently studied. The
Aboriginal processing of resin from Xanthorrhoea (Sol. Ex Sm.) grass tree, Triodia (R.Br.) spinifex and Lechenaultia divaricata (F.Muell.) mindrie, is
reported with experiences and observations about the performance of resin mixtures in hafted tool-use experiments. Pure mixtures of winnowed
Triodia grass, though soft, were more effective as a sticky adhesive than lumps collected from ant nests or the ground following bushfires.
Xanthorrhoea resin mixed with kangaroo dung and charred wood was effective, though brittle, and re-heating made it less sticky and more brittle.
Mindrie root mixed with kangaroo dung and ashes proved highly effective. Triodia, Xanthorrhoea and Lechenaultia resins have different adhesive
properties, and the resin sources, additives and processing techniques all affect how and when hafts break.

Nature Ecology and Evolution, 2021

Little is known about the Pleistocene climatic context of northern Australia at the time of early... more Little is known about the Pleistocene climatic context of northern Australia at the time of early human settlement. Here we
generate a palaeoprecipitation proxy using stable carbon isotope analysis of modern and archaeological pandanus nutshell
from Madjedbebe, Australia’s oldest known archaeological site. We document fluctuations in precipitation over the last 65,000
years and identify periods of lower precipitation during the penultimate and last glacial stages, Marine Isotope Stages 4 and 2.
However, the lowest effective annual precipitation is recorded at the present time. Periods of lower precipitation, including the
earliest phase of occupation, correspond with peaks in exotic stone raw materials and artefact discard at the site. This pattern
is interpreted as suggesting increased group mobility and intensified use of the region during drier periods.

QAR, 1999

This site report presents a description of archaeological investigations undertaken at Big Foot A... more This site report presents a description of archaeological investigations undertaken at Big Foot Art Site, a large rockshelter and art site located at Callia Gorge, eastern Central Queensland, Field and laboratory methods are outlined and results presented, Excavation revealed evidence for occupation spamting from before 7,700 cal BP up to at least 300 cal BP, with a significant peak in stone artefact discard between cA,200-3,200 cal BP, Results are compared to analyses undertaken in the adjacent Central Queensland Highlands,

Nature Communications, 2021

Investigator(s)/Capability: All assessors agree the investigators are ‘world leading’(B), ‘eminen... more Investigator(s)/Capability: All assessors agree the investigators are ‘world leading’(B), ‘eminently qualified’ (A) ‘power houses in their disciplines’ (C), have diverse specialities with long and ‘outstanding’ track records (B), substantial experience in running large projects, in disseminating results in high impact and widely cited/applied publications and in graduating HDR students. It is agreed the team complements one another, greatly enhancing the breadth of the project to ensure success. We clarify (A) that 2 PhDs are requested from the ARC and one provided by the host institution (UQ). The roles of all project PhDs are clearly delineated: 1. usewear and residue; 2. ballistic experimentation; 3. 3D GM analysis. CI and PI Rots will oversee build and testing of projectile equipment and oversee the large number of experiments. PI Collard will oversee 3D GM and perform phylogenetic analyses. The CI and both PIs will facilitate access to collections worldwide and will take part in all phases of research and dissemination.
Project Quality and Innovation: The assessors agree the project ‘addresses new questions in a novel and innovative way’ that is ‘future proof against COVID’ through local analyses and use of ‘excellent international networks’. Assessors state the project methodology is ‘logical and well-designed’, ‘quantitatively robust’ and will ‘fill a huge hole’ in current research. A enquires about the weight of hafting/shaft and projectile points to be used. These variables will be tightly controlled to limit confounding effects. Porcelain points allow tight control over size, shape and weight, while shafts and mastic will be carefully weighed and standardised. Museum collections to be used were all acquired recently with excellent control over sampling and dating (C), while benefits for TOs were identified by excavators as part of consulations and parternships for each project (A). While our four methods of GM, usewear/residues, ballistics and phylogenetic analysis are ‘well established best practice’ (B), B nevertheless questions their novelty. B overlooks that these tried and tested methods have never been combined before in projectile studies and that novelty and strength lies the multistranded ‘cabling’ approach we adopt. A enquires how we will investigate the social, environmental and technological context of projectile development. The CI and PIs have published extensively the contexts of technological innovation and the determinants of assemblage variation. We will closely examine the climatic, ecological, demographic and social context of the hominins engaged in projectile use to determine the conditions giving rise to adoption or rejection of complex projectile use and the spread and proliferation of that technology out of Africa. B asks how the mechanical and actualistic projectile experiments will be combined/compared at UQ and Liège. Experimental design linking controlled and actualistic experiments is achievable through careful planning, detailed knowledge of material properties, dimensions, speeds, target materials and distances to targets. These variables will be standardised at both UQ and Liege to ensure direct comparability of results. Actualistic experiments vary more freely, but because all pertinent aspects of the experiments are quanitified, the results will be directly comparable with the mechanical tests. B asks how local problems of context, raw material and type will be dealt with in phylogenetic analysis. These are common issues that can be dealt with in the attribute matrix and homoplasies are easily dealt with in phylogenetic analysis.
Benefit: All assessors agree this project fills an ‘important knowledge gap’, that the ‘benefits are wide-reaching’ and of ‘global interest to the public’(C), ‘contributing significantly to understanding the origins of our species and its emergence out of Africa’. B states the body of knowledge to be created is ‘fundamental for advancing archaeological research at a global scale’ with excellent potential for ‘understanding human evolution’ and ‘producing high-impact publications’. C enquires about travel costs. These are priced using average pre-pandemic off-peak economy flights between Australia, Canada and Europe ($1500 ea), leaving ~60% of the travel budget for food and accommodation in each year. Travel remains uncertain in the years ahead and project phases will be flexible to accommodate travel restrictions.
Feasibility: All assessors agree the project is ‘inherently feasible’ (C), with logical role divisions, and the ‘expertise and infrastructure to do so successfully’ (A). While international travel is ideal, the project has been designed to accommodate delays and to ensure outcomes irrespective of travel bans. Museum and archaeological collections and ballistic experiments are designed to be conducted by the CI and PIs on each continent if travel restrictions continue, such that ‘outputs are still assured’ (C).

The Oxford Handbook of the Archaeology of Indigenous Australia and New Guinea, 2022

Nature Communications, 2020

Scientific Reports, 2022

Journal of Archaeological Science: Reports, 2021

Australian Archaeology, 2018

Quaternary Science Reviews, 2019

Journal of Archaeogical Science: Reports, 2020

Nature Communications, 2020

Journal of Human Genetics, 2020

Beyond Stones and More Stones, 2017

Quaternary Science Reviews, 2019

EXARC, 2020

Nature Ecology and Evolution, 2021

QAR, 1999

Nature Communications, 2021

Lithic Technology, 2017

Stone suitable for flint knapping is fine-grained and isotropic, sharp, and characteristically pr... more Stone suitable for flint knapping is fine-grained and isotropic, sharp, and characteristically prone to production failures in the hands of novicesThis poses significant problems for university teachers trying to instruct novices in the fundamentals of stone working in limited time during classroom practicals where health and safety concerns must be taken seriously. In this paper I outline a cheap and successful approach to teaching knapping using potatoes-"potato knapping"adopted in several of my courses. This approach allows undergraduates to acquire working knowledge of complex reduction sequences with low risk of self-injury and without the need for any prior skill or training in knapping. This technique is employed successfully to teach complex tasks, such as Levallois flaking, in short practicals, as well as to test various hypotheses and illustrate important concepts in classroom settings. Potato knapping as a research medium also has much potential to answer fundamental anthropological questions, as illustrated by a case study in cultural transmission.

Nature Ecology and Evolution, 2021

Journal of Human Genetics, 2020

New Guineans represent one of the oldest locally continuous populations outside Africa, harboring... more New Guineans represent one of the oldest locally continuous populations outside Africa, harboring among the greatest
linguistic and genetic diversity on the planet. Archeological and genetic evidence suggest that their ancestors reached Sahul
(present day New Guinea and Australia) by at least 55,000 years ago (kya). However, little is known about this early
settlement phase or subsequent dispersal and population structuring over the subsequent period of time. Here we report 379
complete Papuan mitochondrial genomes from across Papua New Guinea, which allow us to reconstruct the phylogenetic
and phylogeographic history of northern Sahul. Our results support the arrival of two groups of settlers in Sahul within the
same broad time window (50–65 kya), each carrying a different set of maternal lineages and settling Northern and Southern
Sahul separately. Strong geographic structure in northern Sahul remains visible today, indicating limited dispersal over time
despite major climatic, cultural, and historical changes. However, following a period of isolation lasting nearly 20 ky after
initial settlement, environmental changes postdating the Last Glacial Maximum stimulated diversification of mtDNA
lineages and greater interactions within and beyond Northern Sahul, to Southern Sahul, Wallacea and beyond. Later, in the
Holocene, populations from New Guinea, in contrast to those of Australia, participated in early interactions with incoming
Asian populations from Island Southeast Asia and continuing into Oceania.

Quaternary Science Reviews, 2019

Art Information exchange Colourants Modern human Modern human behaviour a b s t r a c t The pace ... more Art Information exchange Colourants Modern human Modern human behaviour a b s t r a c t The pace of research undertaken in Sunda (Southeast Asia) through to Sahul (Greater Australia) has increased exponentially over the last three decades, resulting in spectacular discoveries ranging from new hominin species, significant extension to the age for first human occupation in the region, as well as the identification of what is currently the oldest known rock art in the world. These breakthroughs cast the archaeological record of complexity in Sunda, Sahul, and Wallacea in an entirely different light to that of several decades ago, placing it on an equal footingto that of Africa, Asia, and Europe. The archaeological record of these regions now points to rich and diverse early modern human (Homo sapien) societies engaged in complex symbolic and technological behaviours demonstrating capacities for innovation and self-expression found in all modern human groups now around the globe. Here we provide a comprehensive review of all Pleistocene symbolic evidence reported for Sahul, Sunda, and Wallacea to date. We explore how recent findings have changed our perceptions of the first modern human colonists and our understanding of the origins and development of the rich and diverse cultures that arose in each region through time.

Journal of Archaeological Science Reports, 2020

Numerous plant seeds (the caryopsis or achene) from a wide variety of genera were traditionally g... more Numerous plant seeds (the caryopsis or achene) from a wide variety of genera were traditionally ground for food by hunter-gatherer peoples, including over 200 varieties by Aboriginal Australians. In Australia, these seeds varied greatly in size, shape and hardness. Except for a broad distinction being made between grass and tree seeds, differences in the morphological and other characteristics of seeds-in particular their performance in seed-grinding-are rarely documented. A recent experimental examination of the efficiency of millstones using commercial proxies for difficult to obtain Australian native seeds has shown significant differences in work-ability and output of different types of seeds. This paper tests predictions as to whether the grinding characteristics of a number of widely used native seeds also vary significantly, the implications this has for the selection, treatment and use of seeds by Aboriginal people in Australia and elsewhere, and generates quantitative data which can supplement and explicate other experimental research. It also makes a preliminary assessment of whether domesticated seeds can provide useful grinding analogues for unavailable native seeds. Our findings have broad relevance for an understanding of prehistoric seed-grinding and species selection in Australia and other parts of the world.

Nature Communications, 2020

There is little evidence for the role of plant foods in the dispersal of early modern humans into... more There is little evidence for the role of plant foods in the dispersal of early modern humans into new habitats globally. Researchers have hypothesised that early movements of human populations through Island Southeast Asia and into Sahul were driven by the lure of high-calorie, low-handling-cost foods, and that the use of plant foods requiring processing was not common in Sahul until the Holocene. Here we present the analysis of charred plant food remains from Madjedbebe rockshelter in northern Australia, dated to between 65 kya and 53 kya. We demonstrate that Australia's earliest known human population exploited a range of plant foods, including those requiring processing. Our finds predate existing evidence for such subsistence practices in Sahul by at least 23ky. These results suggest that dietary breadth underpinned the success of early modern human populations in this region, with the expenditure of labour on the processing of plants guaranteeing reliable access to nutrients in new environments.

Poster presented at the 2015 Annual Meeting of the Society for American Archaeology

Ground-penetrating radar (GPR) has a variable record in identifying human burials, being least ef... more Ground-penetrating radar (GPR) has a variable record in identifying human burials, being least effective when distinctive burial features such as grave shafts or void spaces are not present, a common situation in Indigenous Australian archaeological sites. A GPR survey was carried out in advance of recent archaeological excavations at Madjedbebe (formaly known as Malakunanja II), a sandstone rockshelter in western Arnhem Land. The combination of detailed mapping, GPR and excavation afforded the opportunity to improve the geophysical interpretation and to document the burial practice of placing rocks over an interred body. The spatial relationship of the rocks and burials were investigated with statistical tests. Application of these methods developed through this case study provides Indigenous communities and other heritage practioners with the future opportunity to assess and manage similar burial sites in a non-invasive fashion. Further it provides a means for data intergration and visual tools for understanding a site's spatial layout.

Madjedbebe (formerly known as Malakunanja II) is noteworthy for the presence of a very large numb... more Madjedbebe (formerly known as Malakunanja II) is noteworthy for the presence of a very large number of ground haematite pieces, grinding stones, and buried exfoliated slabs and other painted stones found at the site. This record of artistic activity and pigment production continues down to the lowest cultural layer, dated by TL and OSL to 50-60kya. Our research combines experimental pigment production and direct application with microscopic analysis of the ground pieces from the lowest layer of the site. We define a characteristic set of attributes for various types of grinding, scoring and rubbing activities. While dry grinding to extract pigment powder is clearly evident on many ground pieces, a wider range of other activities is also indicated, including direct application of pigment to a soft, fatty surface, such as the interior surface of animal hide.