[Show abstract][Hide abstract] ABSTRACT: Sulawesi is the largest and oldest island within Wallacea, a vast zone of oceanic islands separating continental Asia from the Pleistocene landmass of Australia and Papua (Sahul). By one million years ago an unknown hominin lineage had colonized Flores immediately to the south, and by about 50 thousand years ago, modern humans (Homo sapiens) had crossed to Sahul. On the basis of position, oceanic currents and biogeographical context, Sulawesi probably played a pivotal part in these dispersals. Uranium-series dating of speleothem deposits associated with rock art in the limestone karst region of Maros in southwest Sulawesi has revealed that humans were living on the island at least 40 thousand years ago (ref. 5). Here we report new excavations at Talepu in the Walanae Basin northeast of Maros, where in situ stone artefacts associated with fossil remains of megafauna (Bubalus sp., Stegodon and Celebochoerus) have been recovered from stratified deposits that accumulated from before 200 thousand years ago until about 100 thousand years ago. Our findings suggest that Sulawesi, like Flores, was host to a long-established population of archaic hominins, the ancestral origins and taxonomic status of which remain elusive.
[Show abstract][Hide abstract] ABSTRACT: The non-destructive nature of X-ray fluorescence (XRF) spectrometers is a principal reason for an increase in their use in archaeological science over the last 15 years, especially for analysing museum-curated artefacts and in situ site fabrics. Here, we show that low power XRF spectrometry can be detrimental for luminescence dating (surface applications such as mud-wasp nest dating in particular). We investigated the effects of irradiation by X-rays emitted from handheld and benchtop spectrometers on optically stimulated luminescence (OSL) signals. Measurements were taken using a portable OSL (pOSL) unit on the following unprepared archaeological materials: sedimentary quartz grains, pottery, a mud-wasp nest, stone tools and a rock flake with anthropogenically applied pigment and natural pigmentation (iron oxides). We observed an increase in luminescence compared to initial background counts for all materials tested, which could lead to overestimation of age determinations in some situations. Our experiment provides a reminder of the potential effects of X-ray radiation, and the need for thorough documentation of all recording and analytical techniques applied to archaeological materials.
[Show abstract][Hide abstract] ABSTRACT: Shell middens are particularly susceptible to post-depositional processes that can rework and redistribute material through a deposit. As archaeological material is moved from its original primary context, the assumption that a temporal connection exists with spatially associated material becomes tenuous. It therefore becomes critical to identify displaced archaeological material within a deposit to ensure correct chronologies are being built. Radiometric dating techniques can identify individual displaced materials, but are sometimes prohibitively costly to utilise on a large scale. This study presents a new application of amino acid racemisation (AAR) dating that identifies stratigraphically displaced midden shell from within a deposit from the northwest Kimberley, Western Australia. Low-cost AAR analysis of 72 samples identified a sample of downwardly-displaced midden shell. Upon close inspection, comparison of AAR and AMS radiocarbon determinations identified fine-grained inconsistencies. Possible processes generating these discrepancies are considered with future avenues for research presented. While an enormous amount of potential is contained within AAR, more work is required to bring the method to the same level of precision as other commonly utilised dating techniques in archaeological research.
No preview · Article · Oct 2015 · Quaternary International
[Show abstract][Hide abstract] ABSTRACT: Time-averaging is a process that affects almost every form of archaeological deposit. The conflation of two or more units from different time periods masks the true temporal span of units which is hidden by post-depositional processes. The implications of this are obvious as archaeological material found in close stratigraphic association may differ in age by hundreds or thousands of years. Some sites have a greater tendency towards the effects of time-averaging, with shell middens being one of the more susceptible. Conventional approaches to midden excavation or analysis, however, do little to tackle the issue of time-averaging. Using amino acid racemisation (AAR), an intensive relative dating programme was undertaken on shell midden excavated from a potentially time-averaged midden deposit. This approach revealed temporally distinct units that had been conflated into one deposit resulting in shell specimens temporally separated by up to 6000. years being found in close stratigraphic association. The application of AAR allowed us to define the temporal parameters of the various comingled deposits, and in doing so isolate temporal units which showed very different depositional patterns. These contrasting units imply different depositional behaviours and in turn changes in site use through time. This new application of AAR offers a way to approach shell midden archaeology to expose instances and repercussions of time-averaging that were previously hidden.
[Show abstract][Hide abstract] ABSTRACT: A small marine pearl was recovered at the Brremangurey rockshelter, on the Kimberley coast, from layers dating to approximately 2000 years ago. In an area famous for its pearls and history of cultured pearl production, public interest centred on whether the pearl was as old as the layer in which it was contained, or whether it was a recent cultured pearl that had infiltrated down from above. The near-spherical shape of the pearl hinted at a possible cultured origin. Owing to the uniqueness and historic cultural significance of this find, non-invasive analytical techniques were used to investigate whether the Brremangurey pearl was cultured or natural. Midden analysis was further used to assess the likely origin of the pearl within the stratified deposits. Analysis confirmed that the pearl is of natural origin and a dense midden lens of Pinctada albina shells is its likely origin.
No preview · Article · Jun 2015 · Australian Archaeology
[Show abstract][Hide abstract] ABSTRACT: Archaeologists have long been puzzled by the appearance in Europe ∼40-35 thousand years (kyr) ago of a rich corpus of sophisticated artworks, including parietal art (that is, paintings, drawings and engravings on immobile rock surfaces) and portable art (for example, carved figurines), and the absence or scarcity of equivalent, well-dated evidence elsewhere, especially along early human migration routes in South Asia and the Far East, including Wallacea and Australia, where modern humans (Homo sapiens) were established by 50 kyr ago. Here, using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. In addition, a painting of a babirusa ('pig-deer') made at least 35.4 kyr ago is among the earliest dated figurative depictions worldwide, if not the earliest one. Among the implications, it can now be demonstrated that humans were producing rock art by ∼40 kyr ago at opposite ends of the Pleistocene Eurasian world.
[Show abstract][Hide abstract] ABSTRACT: We report the identification of minerals in stratified paint layers from a Wandjina motif in the central Kimberley region, Western Australia, via synchrotron powder diffraction. Interpreting our findings with reference to previous pigment characterisations of Wandjina motifs, we outline the potential of this method for rock art investigations. We particularly highlight the implications of successful major and minor phase identification in very small (~3 μg) pigment samples. The results of this pilot study show that crystallographic data is critical in helping to separate environmental/cultural signatures from post-depositional processes within anthropogenically applied pigments. In Wandjina rock art, crystallography facilitates the examination of the cultural context of rock art production within an assemblage ethnographically known to have undergone regular, ritual repainting.
Full-text · Article · Jun 2014 · Australian Archaeology
[Show abstract][Hide abstract] ABSTRACT: Distinctive mulberry paintings found in northern Australia, particularly those of the Kimberley region, have been argued to represent some of the oldest surviving rock art on the continent. Significant research efforts continue to focus on resolving the age of these motifs, but comparatively little attention has been given to understanding their physical composition and potential source(s). In a pilot investigation, we conclude that (at least) two mineralogically distinct mulberry pigments occur in Gwion motifs and demonstrate that their major components can be indicatively chemically differentiated, non-invasively. Characterization of a ‘quarried’ mulberry ochre source demonstrates that these pigments occur locally as natural minerals.
[Show abstract][Hide abstract] ABSTRACT: Optically-stimulated luminescence (OSL) dating provides the time since sediments and their associated artefacts and fossils were last exposed to sunlight prior to deposition and is therefore an essential tool for establishing chronologies for many disciplines. Further to this, OSL dating provides the chronological link between the landscape/surface processes and human activity, which is inferred from the archaeological evidence within the sediment. No other dating technique of this age range (100 yrs-200 ka) provides this intimate connection between the sedimentary processes and the evidence for human behavior. Without this connection, robust geoarchaeological frameworks can prove difficult to construct and maintain. In this paper, we demonstrate the use of OSL dating techniques in sites across Asia and Oceania, focusing on the Tam Hang caves in northern Laos and the rock shelters of northern Kimberley, Western Australia. OSL dating has proved to be the key to understanding how the geomorphological and geological processes within the karst region of northern Laos are intimately related to human activity. Similarly, in the rock shelters of northern Kimberley OSL dating of the sand sheets within the occupation sites and mud wasp nests over the rock art is critical for developing a geoarchaeological framework for understanding the behavior of the first Australians. This framework is of particular importance as these locations may contain some of the oldest signs of modernity on the continent.
[Show abstract][Hide abstract] ABSTRACT: Liang Bua, a limestone cave on the Indonesian island of Flores, has a depositional sequence that spans the last 95,000 years and includes well-preserved faunal remains. Birds are well represented throughout the stratigraphic sequence at Liang Bua. Here, we present the results of the first comprehensive study of avian remains retrieved from Sector XI, a 2 m by 2 m archaeological excavation along the east wall of the cave. A total of 579 specimens were identified as avian, with 244 belonging to at least 26 non-passerine taxa in 13 families. The late Pleistocene assemblage (23 taxa) includes the first recorded occurrence of vultures in Wallacea, as well as kingfishers, snipes, plovers, parrots, pigeons, and swiftlets. Together, these taxa suggest that during this time the surrounding environment was floristically diverse and included several habitat types. Two of these taxa, the giant marabou Leptoptilos robustus and the vulture Trigonoceps sp., are extinct. Eight taxa were identified in the Holocene assemblage, and five of these were also present in the late Pleistocene. Imperial pigeons Ducula sp. and the Island Collared Dove Streptopelia cf. bitorquata appear only in the Holocene assemblage. The differences in faunal composition between the late Pleistocene and Holocene assemblages may reflect a change in avifaunal composition due to climatic and environmental changes near the Pleistocene–Holocene transition, possibly amplified by impacts associated with the arrival of modern humans; however, the small Holocene sample prevents a firm conclusion about faunal turnover from being made.
Full-text · Article · Jun 2013 · Journal of Vertebrate Paleontology
[Show abstract][Hide abstract] ABSTRACT: We report the results of a test excavation of deposits in a limestone cave sub-chamber located beneath the main chamber of Liang Bua, Flores, Indonesia; the discovery site of the small hominin species, Homo floresiensis. Well-preserved remains of extinct Pleistocene fauna and stone artefacts have previously been identified on the surface of a sediment cone within the sub-chamber. Our excavation of the deposits, at the base of the sediment cone in the sub-chamber (to 130 cm depth) yielded only a few fragmentary bones of extant fauna. Uranium/Thorium (U-series or U/Th) dating of soda straw stalactites excavated from 20 to 130 cm in depth demonstrates that the excavated sediments were deposited during the Holocene. Red Thermoluminescence (TL) dating of the sediments at the base of the excavation (130 cm depth) indicates these sediments were last exposed to sunlight at 84 ± 15 ka (thousand years), similar to red TL ages of cave sediments from the main chamber. Together, these results indicate that the surface faunal remains, which are morphologically analogous to Pleistocene finds from the main chamber excavations, were transported to the sub-chamber relatively recently from the main chamber of Liang Bua and probably originated from conglomerate deposits at the rear of the cave and from deposits around the front entrance. There is no evidence for hominin occupation of the sub-chamber, instead it seems to have acted as a sink for cultural materials and fossil remains transported from the surface via sinkholes. Despite the small number of finds from the test excavation, it is possible that more extensive excavations may yield additional transported cultural and faunal evidence at greater depths.
Full-text · Article · Jan 2013 · Journal of Archaeological Science
[Show abstract][Hide abstract] ABSTRACT: The carpals from the Homo floresiensis type specimen (LB1) lack features that compose the shared, derived complex of the radial side of the wrist in Neandertals and modern humans. This paper comprises a description and three-dimensional morphometric analysis of new carpals from at least one other individual at Liang Bua attributed to H. floresiensis: a right capitate and two hamates. The new capitate is smaller than that of LB1 but is nearly identical in morphology. As with capitates from extant apes, species of Australopithecus, and LB1, the newly described capitate displays a deeply-excavated nonarticular area along its radial aspect, a scaphoid facet that extends into a J-hook articulation on the neck, and a more radially-oriented second metacarpal facet; it also lacks an enlarged palmarly-positioned trapezoid facet. Because there is no accommodation for the derived, palmarly blocky trapezoid that characterizes Homo sapiens and Neandertals, this individual most likely had a plesiomorphically wedge-shaped trapezoid (like LB1). Morphometric analyses confirm the close similarity of the new capitate and that of LB1, and are consistent with previous findings of an overall primitive articular geometry. In general, hamate morphology is more conserved across hominins, and the H. floresiensis specimens fall at the far edge of the range of variation for H. sapiens in a number of metrics. However, the hamate of H. floresiensis is exceptionally small and exhibits a relatively long, stout hamulus lacking the oval-shaped cross-section characteristic of human and Neandertal hamuli (variably present in australopiths). Documentation of a second individual with primitive carpal anatomy from Liang Bua, along with further analysis of trapezoid scaling relative to the capitate in LB1, refutes claims that the wrist of the type specimen represents a modern human with pathology. In total, the carpal anatomy of H. floresiensis supports the hypothesis that the lineage leading to the evolution of this species originated prior to the cladogenetic event that gave rise to modern humans and Neandertals.
Full-text · Article · Jan 2013 · Journal of Human Evolution
[Show abstract][Hide abstract] ABSTRACT: This paper describes in detail the external morphology of LB1/1, the nearly complete and only known cranium of Homo floresiensis. Comparisons were made with a large sample of early groups of the genus Homo to assess primitive, derived, and unique craniofacial traits of LB1 and discuss its evolution. Principal cranial shape differences between H. floresiensis and Homo sapiens are also explored metrically. The LB1 specimen exhibits a marked reductive trend in its facial skeleton, which is comparable to the H. sapiens condition and is probably associated with reduced masticatory stresses. However, LB1 is craniometrically different from H. sapiens showing an extremely small overall cranial size, and the combination of a primitive low and anteriorly narrow vault shape, a relatively prognathic face, a rounded oval foramen that is greatly separated anteriorly from the carotid canal/jugular foramen, and a unique, tall orbital shape. Whereas the neurocranium of LB1 is as small as that of some Homo habilis specimens, it exhibits laterally expanded parietals, a weak suprameatal crest, a moderately flexed occipital, a marked facial reduction, and many other derived features that characterize post-habilis Homo. Other craniofacial characteristics of LB1 include, for example, a relatively narrow frontal squama with flattened right and left sides, a marked frontal keel, posteriorly divergent temporal lines, a posteriorly flexed anteromedial corner of the mandibular fossa, a bulbous lateral end of the supraorbital torus, and a forward protruding maxillary body with a distinct infraorbital sulcus. LB1 is most similar to early Javanese Homo erectus from Sangiran and Trinil in these and other aspects. We conclude that the craniofacial morphology of LB1 is consistent with the hypothesis that H. floresiensis evolved from early Javanese H. erectus with dramatic island dwarfism. However, further field discoveries of early hominin skeletal remains from Flores and detailed analyses of the finds are needed to understand the evolutionary history of this endemic hominin species.
No preview · Article · Dec 2011 · Journal of Human Evolution
[Show abstract][Hide abstract] ABSTRACT: Tropical landscapes evolve at a rapid rate, creating stepped alluvial terraces, dense basin and cone topographies and multilevel cave systems. An understanding of the rate of landscape evolution is crucial for understanding how landscapes respond to tectonic instability and for reconstructing landscapes that have changed over archaeological timescales. The rate of landscape incision as a proxy for karst landscape evolution in Indonesia, a key region in the path of human dispersal, has been established using the rate of karstification – by estimating a chronology for stages of cave development using thermal ionisation mass spectrometry U-series dating on flowstones, and the rate of downcutting – by establishing a chronology for a series of alluvial terraces using red thermoluminescence dating. Using these techniques we have determined that the estimated rate of karstification (113 ± 26 mm ka−1) is slower than the average rate of downcutting (305 ± 24 mm ka−1), and the combined rate of landscape incision (217 ± 18 mm ka−1) is slower than the known rate of tectonic uplift for this region derived from raised coral terraces (450 ± 50 mm ka−1). This suggests that rivers are quicker to respond to tectonic instability, but both cave and river systems display a slower rate of incision and karstification than uplift. Correlations between these components of the landscape system reveal a strong, interacting relationship where defined phases of uplift are reflected in the pattern of karstification and cycles of downcutting. An understanding of this relationship has been pivotal in reconstructing the formation and geomorphic history of archaeological caves such as Liang Bua. Copyright
No preview · Article · Sep 2010 · Journal of Quaternary Science
[Show abstract][Hide abstract] ABSTRACT: Here we report AMS radiocarbon ages associated with rock art in the Kimberley, north-west Australia, from beeswax motifs (26), charcoal pigments (7), a fragment of ochred baler shell used for mixing pigments, and mineral deposits from the base of a pecked cupule. With one exception, these ages are for motifs or paraphernalia associated with the Wandjina painting tradition, which appears to have included a number of contemporaneous art 'styles'. The radiocarbon determinations range from similar to 3800 BP, to modern, a distribution very similar to that previously obtained for wax figures in Northern Territory rock art.
No preview · Article · May 2010 · Rock Art Research