Human occupation of northern Australia by 65,000 years ago.

The time of arrival of people in Australia is an unresolved question. It is relevant to debates about when modern humans first dispersed out of Africa and when their descendants incorporated genetic material from Neanderthals, Denisovans and possibly other hominins. Humans have also been implicated in the extinction of Australia's megafauna. Here we report the results of new excavations conducted at Madjedbebe, a rock shelter in northern Australia. Artefacts in primary depositional context are concentrated in three dense bands, with the stratigraphic integrity of the deposit demonstrated by artefact refits and by optical dating and other analyses of the sediments. Human occupation began around 65,000 years ago, with a distinctive stone tool assemblage including grinding stones, ground ochres, reflective additives and ground-edge hatchet heads. This evidence sets a new minimum age for the arrival of humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans.

Norman Dott (1897-1973) and medical illustration: the importance of art to neurosurgery.

Anatomical information and pathologies have been conveyed through the medium of medical illustrations for centuries. In the formative years of British neurosurgery, Professor Norman Dott (1897-1973) utilised medical illustrations as a means of documenting neurosurgical advances and conveying pathological-anatomical correlation. He commissioned a vast number of medical illustrations over the course of his career, ultimately producing a diverse collection of items, most of which is cared for by Lothian Health Services Archive (LHSA), Edinburgh, Scotland. In this study, the original material from Dott's personal collection was audited. Of 172 stand-alone drawings, 84 were categorised and analysed. The findings are a reflection of Dott's expertise as an academic and a surgeon. Spanning the years 1925-1968, a wide range of pathologies and procedures are depicted including intracranial aneurysms and their ligation, an area in which Dott was renowned for pioneering surgical advances. The collection stands as a testament to Dott's emphasis upon medical illustration to communicate the intricacies and complexities of his field, providing valuable insight into clinical and surgical practice in neurosurgery when the specialty was in its juvenescence. In order to illuminate the connections between biography and specialism that generated an extraordinary visual archive, this study considers the early life and work of Norman Dott and the influence of Harvey Cushing on Dott's prioritisation of visual documentation of surgical practice. It explores the impact of German-American medical artist Max Brödel on the UK, and especially on the artists employed by Dott, before presenting a short review of the medical illustrations they created.

The archaeology, chronology and stratigraphy of Madjedbebe (Malakunanja II): A site in northern Australia with early occupation.

Published ages of >50 ka for occupation at Madjedbebe (Malakunanja II) in Australia's north have kept the site prominent in discussions about the colonisation of Sahul. The site also contains one of the largest stone artefact assemblages in Sahul for this early period. However, the stone artefacts and other important archaeological components of the site have never been described in detail, leading to persistent doubts about its stratigraphic integrity. We report on our analysis of the stone artefacts and faunal and other materials recovered during the 1989 excavations, as well as the stratigraphy and depositional history recorded by the original excavators. We demonstrate that the technology and raw materials of the early assemblage are distinctive from those in the overlying layers. Silcrete and quartzite artefacts are common in the early assemblage, which also includes edge-ground axe fragments and ground haematite. The lower flaked stone assemblage is distinctive, comprising a mix of long convergent flakes, some radial flakes with faceted platforms, and many small thin silcrete flakes that we interpret as thinning flakes. Residue and use-wear analysis indicate occasional grinding of haematite and woodworking, as well as frequent abrading of platform edges on thinning flakes. We conclude that previous claims of extensive displacement of artefacts and post-depositional disturbance may have been overstated. The stone artefacts and stratigraphic details support previous claims for human occupation 50-60 ka and show that human occupation during this time differed from later periods. We discuss the implications of these new data for understanding the first human colonisation of Sahul.

65,000-years of continuous grinding stone use at Madjedbebe, Northern Australia.

Grinding stones and ground stone implements are important technological innovations in later human evolution, allowing the exploitation and use of new plant foods, novel tools (e.g., bone points and edge ground axes) and ground pigments. Excavations at the site of Madjedbebe recovered Australia's (if not one of the world's) largest and longest records of Pleistocene grinding stones, which span the past 65 thousand years (ka). Microscopic and chemical analyses show that the Madjedbebe grinding stone assemblage displays the earliest known evidence for seed grinding and intensive plant use, the earliest known production and use of edge-ground stone hatchets (aka axes), and the earliest intensive use of ground ochre pigments in Sahul (the Pleistocene landmass of Australia and New Guinea). The Madjedbebe grinding stone assemblage reveals economic, technological and symbolic innovations exemplary of the phenotypic plasticity of Homo sapiens dispersing out of Africa and into Sahul.

Emergence of a Neolithic in highland New Guinea by 5000 to 4000 years ago.

The emergence of agriculture was one of the most notable behavioral transformations in human history, driving innovations in technologies and settlement globally, referred to as the Neolithic. Wetland agriculture originated in the New Guinea highlands during the mid-Holocene (8000 to 4000 years ago), yet it is unclear if there was associated behavioral change. Here, we report the earliest figurative stone carving and formally manufactured pestles in Oceania, dating to 5050 to 4200 years ago. These discoveries, at the highland site of Waim, occur with the earliest planilateral axe-adzes in New Guinea, the first evidence for fibercraft, and interisland obsidian transfer. The combination of symbolic social systems, complex technologies, and highland agricultural intensification supports an independent emergence of a Neolithic ~1000 years before the arrival of Neolithic migrants (Lapita) from Southeast Asia.

Quandong stones: A specialised Australian nut-cracking tool.

The quandong or native peach (Santalum acuminatum R.Br.) has been recognised as an important and tasty food resource among Aboriginal Australians in arid and semi-arid areas of southern Australia. It is valued for its fruit that is consumed raw or dried, and for its kernel, which is eaten raw or ground into paste for medicinal and skin care purposes. This paper reports on a study of ground stone implements within the Murray Darling Basin that has identified quandong stones as a distinct type of implement made specifically for the efficient cracking of quandong nuts. Data are presented on 1,327 ground stone implements from collections in 12 different locations in the Murray-Darling Basin (MDB), an area almost completely devoid of stone sources. Given the paucity of stone, multi-purpose use of implements is widely documented. Although it was common to find pits present in mortars and other ground stone tools demonstrating multiple functions, including use as anvils, a class of single purpose stones with multiple pits and distinctive form was identified. Most of these were found in areas known for groves of quandong and four were analysed for use-wear and residues along with two other ground stone items from the MDB. The results support their identification as specialised anvil stones for cracking quandong nuts.

Combined organic biomarker and use-wear analyses of stone artefacts from Liang Bua, Flores, Indonesia.

Organic biomarker and lithic use-wear analyses of archaeological implements manufactured and/or used by hominins in the past offers a means of assessing how prehistoric peoples utilised natural resources. Currently, most studies focus on one of these techniques, rather than using both in sequence. This study aims to assess the potential of combining both methods to analyse stone artefacts, using a set of 69 stones excavated from the cave site of Liang Bua (Flores, Indonesia). Prior to chemical analysis, an initial inspection of the artefacts revealed potential use-wear traces but no visible residues. Gas chromatography mass spectrometry (GC-MS) analysis, including the targeting of 86 lipids, terpenes, terpenoids, alkanes and their analogues, found compounds with plant or animal origin on 27 of the 69 stones. The artefacts were subsequently cleaned, and use-wear analysis identified traces of use on 43 artefacts. Use-wear analysis confirmed traces of use on 23 of the 27 artefacts with potential use-residues that were determined by GC-MS. The GC-MS results were broadly consistent with the functional classes identified in the later use-wear analysis. This inclusive approach for stone artefact analysis strengthens the identifications made through multiple lines of enquiry. There remain conflicts and uncertainties in specific cases, suggesting the need for further refinement and analyses of the relationships between use-wear and residues.

Correction: Making Sense of Residues on Flaked Stone Artefacts: Learning from Blind Tests.

[This corrects the article DOI: 10.1371/journal.pone.0150437.].

Making Sense of Residues on Flaked Stone Artefacts: Learning from Blind Tests.

Residue analysis has become a frequently applied method for identifying prehistoric stone tool use. Residues adhering to the stone tool with varying frequencies are interpreted as being the result of an intentional contact with the worked material during use. Yet, other processes during the life cycle of a stone tool or after deposition may leave residues and these residues may potentially lead to misinterpretations. We present a blind test that was designed to examine this issue. Results confirm that production, retouch, prehension, hafting, various incidental contacts during use and deposition may lead to residue depositions that significantly affect the accurateness of identifications of tool-use. All currently applied residue approaches are concerned. We therefore argue for a closer interaction with independent wear studies and a step-wise procedure in which a low magnification of wear traces is used as a first step for selecting potentially used flakes in archaeological contexts. In addition, residue concentrations on a tool's edge should be sufficiently dense before linking them with use.