RESUMO
As the south-westernmost region of Europe, the Iberian Peninsula stands as a key area for understanding the process of modern human dispersal into Eurasia. However, the precise timing, ecological setting and cultural context of this process remains controversial concerning its spatiotemporal distribution within the different regions of the peninsula. While traditional models assumed that the whole Iberian hinterland was avoided by modern humans due to ecological factors until the retreat of the Last Glacial Maximum, recent research has demonstrated that hunter-gatherers entered the Iberian interior at least during Solutrean times. We provide a multi-proxy geoarchaeological, chronometric and paleoecological study on human-environment interactions based on the key site of Peña Capón (Guadalajara, Spain). Results show (1) that this site hosts the oldest modern human presence recorded to date in central Iberia, associated to pre-Solutrean cultural traditions around 26,000 years ago, and (2) that this presence occurred during Heinrich Stadial 2 within harsh environmental conditions. These findings demonstrate that this area of the Iberian hinterland was recurrently occupied regardless of climate and environmental variability, thus challenging the widely accepted hypothesis that ecological risk hampered the human settlement of the Iberian interior highlands since the first arrival of modern humans to Southwest Europe.
Assuntos
Migração Humana/história , Animais , Arqueologia , Teorema de Bayes , Carvão Vegetal/história , Clima , Meio Ambiente , Fósseis/história , Sedimentos Geológicos/análise , Fenômenos Geológicos , História Antiga , Humanos , Modelos Biológicos , Pólen/química , Dinâmica Populacional/história , Datação Radiométrica , Espanha , Vertebrados , Madeira/históriaRESUMO
The megalithic jar sites of Laos (often referred to as the Plain of Jars) remain one of Southeast Asia's most mysterious and least understood archaeological cultures. The sites, recently inscribed as UNESCO World Heritage, host hollowed stone jars, up to three metres in height, which appear scattered across the landscape, alone or clustered in groups of up to more than 400. Until now, it has not been possible to estimate when the jars were first placed on the landscape or from where the stone was sourced. Geochronological analysis using the age of detrital zircons demonstrates a likely quarry source for one of the largest megalithic jar sites. Optically Stimulated Luminescence (OSL) dating suggests the jars were positioned at the sites potentially as early as the late second millennium BC. Radiocarbon dating of skeletal remains and charcoal samples places mortuary activity around the jars from the 9-13th century AD, suggesting the sites have maintained ritual significance from the period of their initial placement until historic times.
Assuntos
Fósseis/história , Sedimentos Geológicos/análise , Dosimetria por Luminescência Estimulada Opticamente/métodos , Arqueologia , Carvão Vegetal/história , Cultura , História Antiga , História Medieval , Humanos , Laos , Chumbo/análise , Datação Radiométrica/métodos , Silicatos/análise , Zircônio/análiseAssuntos
Carvão Mineral/história , DNA/química , DNA/história , Virologia/história , Difração de Raios X/história , Carvão Vegetal/química , Carvão Vegetal/história , Grafite/química , Grafite/história , História do Século XX , Humanos , Poliovirus/química , Dispositivos de Proteção Respiratória/história , Vírus do Mosaico do Tabaco/químicaRESUMO
The presence of biochar with high carbon accumulation capacity and nutrient adsorption is causally associated with archeological soils. Although this type of soil organic matter has been known for a long time, the knowledge of its structure and environmental behavior is still limited. This work used Raman spectroscopy to obtain structural information and identify alterations in biochar particles. To this end, we studied biochar particles found in an archaeological site with a temporal window lasting 12451 to 11080 yr cal BP. The molecular, structural and sp2/sp3 characteristics of the charcoal particles were determined at the time of burning and associated with the temperature, time and characteristics of the burnt material. We propose that the process of oxidation of the biochar occurs during the first 2000 years after its genesis. The oxidation process is a reflection of decreases in the number of defects related to sp2 bonds on amorphous carbons and increases in the number of defects associated with ionic impurities, which clearly indicate the interaction between biochar particles and the soil matrix. The data confirm the hypothesis that the persistence of biochar in the environment is due to its graphite structure and suggest that over a 12000 year timeframe, biochar particles undergo several changes that occur in the disordered phase and are rapidly oxidized.
Assuntos
Carvão Vegetal/química , Carvão Vegetal/história , Poluentes do Solo/química , Solo/química , Análise Espectral Raman/métodos , História do Século XVII , História do Século XX , História Antiga , História Medieval , Humanos , Fatores de TempoRESUMO
According to Herodotus, the use of charcoal was introduced in ancient Egypt; however only in 1773 Carl Willhelm Scheele utilized it for adsorbing gases. Finally, Hippocrates Yatzidis in 1963 demonstrated its binding capacity for toxic substances of endogenous or exogenous origin and used it for hemoperfusion systems.
Assuntos
Carvão Vegetal/história , Diálise/história , Hemoperfusão/história , Rins Artificiais/história , Grécia , História do Século XVIII , História do Século XIX , História do Século XX , História Antiga , HumanosRESUMO
The Ushki Paleolithic sites of Kamchatka, Russia, have long been thought to contain information critical to the peopling of the Americas, especially the origins of Clovis. New radiocarbon dates indicate that human occupation of Ushki began only 13,000 calendar years ago-nearly 4000 years later than previously thought. Although biface industries were widespread across Beringia contemporaneous to the time of Clovis in western North America, these data suggest that late-glacial Siberians did not spread into Beringia until the end of the Pleistocene, perhaps too recently to have been ancestral to proposed pre-Clovis populations in the Americas.