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1.
Nature ; 565(7737): 82-85, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30455423

RESUMEN

Levallois approaches are one of the best known variants of prepared-core technologies, and are an important hallmark of stone technologies developed around 300,000 years ago in Africa and west Eurasia1,2. Existing archaeological evidence suggests that the stone technology of east Asian hominins lacked a Levallois component during the late Middle Pleistocene epoch and it is not until the Late Pleistocene (around 40,000-30,000 years ago) that this technology spread into east Asia in association with a dispersal of modern humans. Here we present evidence of Levallois technology from the lithic assemblage of the Guanyindong Cave site in southwest China, dated to approximately 170,000-80,000 years ago. To our knowledge, this is the earliest evidence of Levallois technology in east Asia. Our findings thus challenge the existing model of the origin and spread of Levallois technologies in east Asia and its links to a Late Pleistocene dispersal of modern humans.


Asunto(s)
Arqueología , Cuevas , Fósiles , Hominidae , Comportamiento del Uso de la Herramienta , África , Animales , China , Europa (Continente) , Asia Oriental , Historia Antigua , Humanos , Factores de Tiempo
2.
Nature ; 547(7663): 306-310, 2017 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-28726833

RESUMEN

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.


Asunto(s)
Migración Humana/historia , África/etnología , Animales , Australia , Dieta/historia , Fósiles , Sedimentos Geológicos/análisis , Historia Antigua , Humanos , Hombre de Neandertal
3.
PLoS Comput Biol ; 16(11): e1008316, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33170857

RESUMEN

Computational science has been greatly improved by the use of containers for packaging software and data dependencies. In a scholarly context, the main drivers for using these containers are transparency and support of reproducibility; in turn, a workflow's reproducibility can be greatly affected by the choices that are made with respect to building containers. In many cases, the build process for the container's image is created from instructions provided in a Dockerfile format. In support of this approach, we present a set of rules to help researchers write understandable Dockerfiles for typical data science workflows. By following the rules in this article, researchers can create containers suitable for sharing with fellow scientists, for including in scholarly communication such as education or scientific papers, and for effective and sustainable personal workflows.


Asunto(s)
Ciencia de los Datos , Guías como Asunto , Lenguajes de Programación , Programas Informáticos , Algoritmos , Reproducibilidad de los Resultados
4.
J Hum Evol ; 101: 45-64, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27886810

RESUMEN

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 pattern, we argue, that 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.


Asunto(s)
Evolución Biológica , Fósiles , Hominidae , Tecnología , Animales , Arqueología , Peces , Humanos , Timor Oriental
5.
J Hum Evol ; 83: 46-64, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25957653

RESUMEN

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.


Asunto(s)
Arqueología/métodos , Ocupaciones/historia , Artefactos , Australia , Historia Antigua , Humanos , Tecnología/historia
7.
Evol Hum Sci ; 42022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35663508

RESUMEN

2021 marked the fiftieth anniversary of the publication of Robert C. Dunnell's (1971) diminutive yet dense Systematics in Prehistory. At the height of the debate between Culture History and New Archaeology, Dunnell's work sought to address a more fundamental issue that was and still is relevant to all branches of prehistoric archaeology, and especially to the study of the Palaeolithic: systematics. Dunnell himself was notorious and controversial, however, but the importance of his work remains underappreciated. Like other precocious works of that tumultuous time Systematics in Prehistory today remains absent from most course reading lists and gathers dust on library shelves. In this contribution we argue for a greater appreciation of its as yet unfulfilled conceptual and analytical promise. In particular, we briefly chart its somewhat delayed impact via evolutionary archaeology, including how it has also influenced non-Anglophone traditions, especially in South America. The obstinate persistence of classification issues in palaeoanthropology and palaeoarchaeology, we argue, warrants a second look at Dunnell's Systematics.

8.
Sci Rep ; 12(1): 11747, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35817808

RESUMEN

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.


Asunto(s)
Huesos , Tecnología , África , Arqueología , Australia , Humanos , Nueva Guinea
9.
Front Aging Neurosci ; 13: 720167, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34566623

RESUMEN

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by neuronal loss, extracellular amyloid-ß (Aß) plaques, and intracellular neurofibrillary tau tangles. A diagnosis is currently made from the presenting symptoms, and the only definitive diagnosis can be done post-mortem. Over recent years, significant advances have been made in using ocular biomarkers to diagnose various neurodegenerative diseases, including AD. As the eye is an extension of the central nervous system (CNS), reviewing changes in the eye's biology could lead to developing a series of non-invasive, differential diagnostic tests for AD that could be further applied to other diseases. Significant changes have been identified in the retinal nerve fiber layer (RNFL), cornea, ocular vasculature, and retina. In the present paper, we review current research and assess some ocular biomarkers' accuracy and reliability that could potentially be used for diagnostic purposes. Additionally, we review the various imaging techniques used in the measurement of these biomarkers.

10.
Nat Ecol Evol ; 5(3): 295-303, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33495592

RESUMEN

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.


Asunto(s)
Fósiles , Pandanaceae , Arqueología , Australia , Humanos , Ocupaciones
11.
Nat Commun ; 11(1): 924, 2020 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-32066741

RESUMEN

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.


Asunto(s)
Domesticación , Conducta Alimentaria , Migración Humana/historia , Plantas Comestibles , Australia , Manipulación de Alimentos/historia , Fósiles , Historia Antigua , Humanos
12.
Science ; 365(6456): 897-902, 2019 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-31467217

RESUMEN

Environmentally transformative human use of land accelerated with the emergence of agriculture, but the extent, trajectory, and implications of these early changes are not well understood. An empirical global assessment of land use from 10,000 years before the present (yr B.P.) to 1850 CE reveals a planet largely transformed by hunter-gatherers, farmers, and pastoralists by 3000 years ago, considerably earlier than the dates in the land-use reconstructions commonly used by Earth scientists. Synthesis of knowledge contributed by more than 250 archaeologists highlighted gaps in archaeological expertise and data quality, which peaked for 2000 yr B.P. and in traditionally studied and wealthier regions. Archaeological reconstruction of global land-use history illuminates the deep roots of Earth's transformation and challenges the emerging Anthropocene paradigm that large-scale anthropogenic global environmental change is mostly a recent phenomenon.

14.
Science ; 355(6323): 357-358, 2017 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-28126779
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