Sue O’Connor

Islands Under the Sea: A Review of Early Modern Human Dispersal Routes and Migration Hypotheses Through Wallacea

ABSTRACT Wallacea is the transitional biogeographic zone between the continents of Sunda (Southeast Asia) and Sahul (Australian-New Guinea). It consists of a series of island chains unique in the region for never having been connected to either continent. Movement of early modern humans from Sunda to Sahul during the late Pleistocene required dispersal through Wallacea, and hence would have necessitated sea crossings. However, the archeological evidence for early modern humans in Wallacea is still a work in progress, and none of it pre-dates the archeological record from Sahul. While numerous models of this significant colonization event have been proposed, selecting the most likely model for first landfall in Sahul using current archeological evidence has proven difficult, if not impossible. Here the late Pleistocene archeological evidence of early modern humans from Wallacea and its neighbors are reviewed, and the key colonization models that have been proposed are explored. We consider the use of computer simulations and the input variables necessary to test the likelihood of the different colonization models. We highlight the importance of the greater than 100 additional submerged islands observed within the Wallacean archipelago following a simple analysis of bathymetric data and sea-level curves, and their potential impacts on the dispersal and ecology of early human colonizers.

World’s earliest ground-edge axe production coincides with human colonisation of Australia

Abstract We report evidence for the world’s earliest ground-edge axe, 44–49,000 years old. Its antiquity coincides with or immediately follows the arrival of humans on the Australian landmass. Ground/polished axes are not associated with the eastward dispersal of Homo sapiens across Eurasia and the discovery of axes in Australia at the point of colonisation exemplifies a diversification of technological practices that occurred as modern humans dispersed from Africa. Ground-edge axes are now known from two different colonised lands at the time humans arrived and hence we argue that these technological strategies are associated with the adaptation of economies and social practices to new environmental contexts.

Direct dating of Pleistocene stegodon from Timor Island, East Nusa Tenggara

Stegodons are a commonly recovered extinct proboscidean (elephants and allies) from the Pleistocene record of Southeast Asian oceanic islands. Estimates on when stegodons arrived on individual islands and the timings of their extinctions are poorly constrained due to few reported direct geochronological analyses of their remains. Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor. The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island. On the basis of current data, we find no evidence for significant environmental changes or the presence of modern humans in the region during that time. Thus, we do not consider either of these factors to have contributed significantly to their extinction. In the absence of these, we propose that their extinction was possibly the result of long-term demographic and genetic declines associated with an isolated island population.

The effect of retouch intensity on mid to late Holocene unifacial and bifacial points from the Kimberley

Abstract Stone points have provided key data for studies of hunter gatherer lifeways in several parts of the world. Point technologies occur widely across northern Australia, appearing around the mid-Holocene and persisting into the European Contact period. These points exhibit high-morphological variation, and include bifacial, unifacial and other forms. In the Northern Territory and north Queensland, points have been shown to form part of a reduction continuum. However, in the Kimberley region of Western Australia, similar reconstructions of artefact life history have not been conducted. Using a recently excavated assemblage with a large sample of retouched unifacial and bifacial points (n = 137), we examine the effect of retouch intensity on changing point morphology. Quantification of point reduction reveals a complex artefact life history having compelling parallels with point assemblages from other parts of northern Australia. Drivers for the inception of point technology in northern Australia are likely to be multiple, including environmental change, population change and social signalling.

A 600-year-old Boomerang fragment from Riwi Cave(South Central Kimberley, Western Australia)

Abstract A small fragment of a carefully shaped wooden artefact was recovered from Riwi Cave (south central Kimberley, Western Australia) during 2013 excavations. Directly dated to 670 ± 20 BP, analysis of the artefact’s wood taxon, morphology, manufacturing traces, use wear, and residues, in addition to comparison with ethnographic examples of wooden technology from the Kimberley region, allowed for the identification of the tool from which it originated: a boomerang. In particular, this artefact most closely resembles the trailing tip of a hooked boomerang, providing rare insights into the presence of these iconic fighting and ceremonial items in the Kimberley some 600 years ago.

Hominin Dispersal and Settlement East of Huxley’s Line: The Role of Sea Level Changes, Island Size, and Subsistence Behavior

The thousands of islands east of Huxley’s Line have never formed a single land mass or been connected to Sunda or Sahul. The earliest records of hominins in this area are stone tools recovered from Pleistocene deposits on Flores and Sulawesi. Subsistence by these hominins as well as the later subsistence patterns exhibited by Homo floresiensis suggest that exploitation of marine resources was, at best, rare and opportunistic. Likewise, the fragmentary hominin remains recovered from Late Pleistocene deposits from Callao Cave in the Philippines exploited large game at the expense of marine resources. In contrast, the earliest zooarchaeological records of modern humans are dominated by marine fish and shellfish and include the earliest evidence of pelagic fishing using shell tools, implying complex fish-capture technology. Pleistocene lithic assemblages on these islands are unspecialized, indicating reduction of predominantly locally available stone to produce flakes and irregularly retouched pieces. By the terminal Pleistocene, records of human subsistence on very small islands indicate almost total reliance on marine foods for protein. We propose that strong links exist between subsistence strategies and dispersal throughout Wallacea, with subsistence strategies available to pre-sapiens hominins in the region being a major limiting factor in their dispersal.

The Walandawe tradition from Southeast Sulawesi and osseous artifact traditions in island Southeast Asia

This chapter describes a sample of points and other osseous artifacts recovered from Holocene contexts at three sites in Walandawe, Southeast Sulawesi, Indonesia. Microscopic observations of use traces and manufacturing techniques are presented as well as metrical observations and morphological classifications. The points show a suite of temporal trends apparently related to a shift from a predominant use as hafted projectile points to their growing use as penetrative tools. Trends include a higher incidence of wear and decline in tip damage, a decrease in bipoint production, an increased focus on unipoints, and a manufacturing shift from predominantly scraping cortical bone to frequently grinding suid incisors and long-bone shafts. Notwithstanding these changes, the Walandawe osseous artifacts constitute an identifiable tradition with systematic differences from other Island Southeast Asian assemblages located in southwest Sulawesi and especially Borneo, the Aru Islands, the northern Moluccas and the New Guinea Bird’s Head.

New dates on dingo bones from Madura Cave provide oldest firm evidence for arrival of the species in Australia

The dingo is the only placental land mammal aside from murids and bats to have made the water crossings to reach Australia prior to European arrival. It is thought that they arrived as a commensal animal with people, some time in the mid Holocene. However, the timing of their arrival is still a subject of major debate with published age estimates varying widely. This is largely because the age estimates for dingo arrival are based on archaeological deposit dates and genetic divergence estimates, rather than on the dingo bones themselves. Currently, estimates vary from between 5000–4000 years ago, for finds from archaeological contexts, and as much as 18,000 based on DNA age estimates. The timing of dingo arrival is important as post arrival they transformed Indigenous societies across mainland Australia and have been implicated in the extinction of a number of animals including the Tasmanian tiger. Here we present the results of direct dating of dingo bones from their oldest known archaeological context, Madura Cave on the Nullarbor Plain. These dates demonstrate that dingoes were in southern Australia by between 3348 and 3081 years ago. We suggest that following their introduction the dingo may have spread extremely rapidly throughout mainland Australia.

Complex history of dog ( Canis familiaris ) origins and translocations in the Pacific revealed by ancient mitogenomes

Archaeological evidence suggests that dogs were introduced to the islands of Oceania via Island Southeast Asia around 3,300 years ago, and reached the eastern islands of Polynesia by the fourteenth century AD. This dispersal is intimately tied to human expansion, but the involvement of dogs in Pacific migrations is not well understood. Our analyses of seven new complete ancient mitogenomes and five partial mtDNA sequences from archaeological dog specimens from Mainland and Island Southeast Asia and the Pacific suggests at least three dog dispersal events into the region, in addition to the introduction of dingoes to Australia. We see an early introduction of dogs to Island Southeast Asia, which does not appear to extend into the islands of Oceania. A shared haplogroup identified between Iron Age Taiwanese dogs, terminal-Lapita and post-Lapita dogs suggests that at least one dog lineage was introduced to Near Oceania by or as the result of interactions with Austronesian language speakers associated with the Lapita Cultural Complex. We did not find any evidence that these dogs were successfully transported beyond New Guinea. Finally, we identify a widespread dog clade found across the Pacific, including the islands of Polynesia, which likely suggests a post-Lapita dog introduction from southern Island Southeast Asia.

Indigenous built structures and anthropogenic impacts on the stratigraphy of Northern Australian rockshelters: insights from Malarrak 1, north western Arnhem Land

Abstract Malarrak 1 is currently the northernmost excavated rockshelter on the Australian mainland, located in the Wellington Range in north western Arnhem Land. The site contains a rich late Holocene deposit, with extensive contact rock art, stone artefacts, shell, bone, contact materials, ancestral human remains, and other cultural material. Excavation of the Malarrak 1 rockshelter and analysis of its sediments revealed many impacts on site formation processes within the deposit. We attribute the disturbance to possible erosion or sediment deposition during periods of intense rainfall and also to the construction of timber structures within the site. This is supported by modern and historical observations and is the focus of this paper. The extent of the disturbance to Malarrak 1 provides a cautionary tale for other excavations in the region that may be affected by similar Indigenous site occupation, as these anthropogenic activities enhance the risk of further impacts arising from biological and geomorphological processes that can impinge on the stratigraphic integrity of the cultural deposits.