[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.
[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.
125th Annual Meeting of the Geological Society of America, Denver Colorado; 10/2013
[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.
[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.
[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.
Journal of Human Evolution 01/2013; 64(2). DOI:10.1016/j.jhevol.2012.10.003 · 3.73 Impact Factor
[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.
Journal of Human Evolution 12/2011; 61(6):644-82. DOI:10.1016/j.jhevol.2011.08.008 · 3.73 Impact Factor
[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
[Show abstract][Hide abstract] ABSTRACT: Previous excavations at Mata Menge and Boa Lesa in the Soa Basin of Flores, Indonesia, recovered stone artefacts in association with fossilized remains of the large-bodied Stegodon florensis florensis. Zircon fission-track ages from these sites indicated that hominins had colonized the island by 0.88 +/- 0.07 million years (Myr) ago. Here we describe the contents, context and age of Wolo Sege, a recently discovered archaeological site in the Soa Basin that has in situ stone artefacts and that lies stratigraphically below Mata Menge and immediately above the basement breccias of the basin. We show using (40)Ar/(39)Ar dating that an ignimbrite overlying the artefact layers at Wolo Sege was erupted 1.02 +/- 0.02 Myr ago, providing a new minimum age for hominins on Flores. This predates the disappearance from the Soa Basin of 'pygmy' Stegodon sondaari and Geochelone spp. (giant tortoise), as evident at the nearby site of Tangi Talo, which has been dated to 0.90 +/- 0.07 Myr ago. It now seems that this extirpation or possible extinction event and the associated faunal turnover were the result of natural processes rather than the arrival of hominins. It also appears that the volcanic and fluvio-lacustrine deposits infilling the Soa Basin may not be old enough to register the initial arrival of hominins on the island.
[Show abstract][Hide abstract] ABSTRACT: The stone technology from Mata Menge on Flores, Indonesia, is described, providing the first detailed analysis of the largest stone artefact assemblage from a stratified and securely dated Middle Pleistocene site in Southeast Asia. Technological analysis indicates a reduction sequence based on the centripetal, or “radial”, reduction of transported blanks. The implications for early hominin behaviour on Flores are considered.
[Show abstract][Hide abstract] ABSTRACT: Evidence from Liang Bua, a limestone cave on the island of Flores in East Indonesia, provides a unique opportunity to explore the long term relationship between hominins and their environment. Occupation deposits at the site span ∼95 ka and contain abundant stone artefacts, well preserved faunal remains and evidence for an endemic species of hominin: Homo floresiensis. Work at the site included detailed geomorphological and environmental analysis, which has enabled comparisons to be drawn between changes in the occupational intensity in the cave, using stone tool and faunal counts, and changes in the environmental conditions, using the characteristics of the sedimentary layers in the cave and speleothem records. These comparisons demonstrate that H. floresiensis endured rapidly fluctuating environmental conditions over the last ∼100 ka, which influenced the geomorphological processes in the cave and their occupational conditions. The intensity of occupation in the cave changed significantly between 95 and 17 ka, with peaks in occupation occurring at 100–95, 74–61 and 18–17 ka. These correlate with episodes of channel formation and erosion in the cave, which in turn correspond with high rainfall, thick soils and high bio-productivity outside. In contrast, periods of low occupational intensity correlate with reduced channel activity and pooling associated with drier periods from 94 to 75 and 36 to 19 ka. This apparent link between intensity of hominin use of the cave and the general conditions outside relates to the expansion and contraction of the rainforest and the ability of H. floresiensis to adapt to habitat changes. This interpretation implies that these diminutive hominins were able to survive abrupt and prolonged environmental changes by changing their favoured occupation sites. These data provide the basis for a model of human–environment interactions on the island of Flores. With the addition of extra data from other sites on Flores, this model will provide a greater understanding of H. floresiensis as a unique human species.
[Show abstract][Hide abstract] ABSTRACT: Earlier observations of the virtual endocast of LB1, the type specimen for Homo floresiensis, are reviewed, extended, and interpreted. Seven derived features of LB1's cerebral cortex are detailed: a caudally-positioned occipital lobe, lack of a rostrally-located lunate sulcus, a caudally-expanded temporal lobe, advanced morphology of the lateral prefrontal cortex, shape of the rostral prefrontal cortex, enlarged gyri in the frontopolar region, and an expanded orbitofrontal cortex. These features indicate that LB1's brain was globally reorganized despite its ape-sized cranial capacity (417 cm3). Neurological reorganization may thus form the basis for the cognitive abilities attributed to H. floresiensis. Because of its tiny cranial capacity, some workers think that LB1 represents a Homo sapiens individual that was afflicted with microcephaly, or some other pathology, rather than a new species of hominin. We respond to concerns about our earlier study of microcephalics compared with normal individuals, and reaffirm that LB1 did not suffer from this pathology. The intense controversy about LB1 reflects an older continuing dispute about the relative evolutionary importance of brain size versus neurological reorganization. LB1 may help resolve this debate and illuminate constraints that governed hominin brain evolution.
Journal of Human Evolution 11/2009; 57(5-57):597-607. DOI:10.1016/j.jhevol.2008.10.008 · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Excavations at Liang Bua, on the Indonesian island of Flores, have yielded a stratified sequence of stone artifacts and faunal remains spanning the last 95k.yr., which includes the skeletal remains of two human species, Homo sapiens in the Holocene and Homo floresiensis in the Pleistocene. This paper summarizes and focuses on some of the evidence for Homo floresiensis in context, as presented in this Special Issue edition of the Journal of Human Evolution and elsewhere. Attempts to dismiss the Pleistocene hominins (and the type specimen LB1 in particular) as pathological pygmy humans are not compatible with detailed analyses of the skull, teeth, brain endocast, and postcranium. We initially concluded that H. floresiensis may have evolved by insular dwarfing of a larger-bodied hominin species over 880k.yr. or more. However, recovery of additional specimens and the numerous primitive morphological traits seen throughout the skeleton suggest instead that it is more likely to be a late representative of a small-bodied lineage that exited Africa before the emergence of Homo erectus sensu lato. Homo floresiensis is clearly not an australopithecine, but does retain many aspects of anatomy (and perhaps behavior) that are probably plesiomorphic for the genus Homo. We also discuss some of the other implications of this tiny, endemic species for early hominin dispersal and evolution (e.g., for the "Out of Africa 1" paradigm and more specifically for colonizing Southeast Asia), and we present options for future research in the region.
Journal of Human Evolution 11/2009; 57(5):640-8. DOI:10.1016/j.jhevol.2009.08.003 · 3.73 Impact Factor