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1.
Nature ; 615(7950): 117-126, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859578

RESUMO

Modern humans have populated Europe for more than 45,000 years1,2. Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period3. Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe4, but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants.


Assuntos
Arqueologia , Genoma Humano , Genômica , Genética Humana , Caça , Paleontologia , Humanos , Europa (Continente)/etnologia , Pool Gênico , História Antiga , Genoma Humano/genética
2.
Proc Natl Acad Sci U S A ; 109(22): 8445-9, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22566638

RESUMO

Early Neolithic sedentary villagers started cultivating wild cereals in the Near East 11,500 y ago [Pre-Pottery Neolithic A (PPNA)]. Recent discoveries indicated that Cyprus was frequented by Late PPNA people, but the earliest evidence until now for both the use of cereals and Neolithic villages on the island dates to 10,400 y ago. Here we present the recent archaeological excavation at Klimonas, which demonstrates that established villagers were living on Cyprus between 11,100 and 10,600 y ago. Villagers had stone artifacts and buildings (including a remarkable 10-m diameter communal building) that were similar to those found on Late PPNA sites on the mainland. Cereals were introduced from the Levant, and meat was obtained by hunting the only ungulate living on the island, a small indigenous Cypriot wild boar. Cats and small domestic dogs were brought from the mainland. This colonization suggests well-developed maritime capabilities by the PPNA period, but also that migration from the mainland may have occurred shortly after the beginning of agriculture.


Assuntos
Agricultura/história , Grão Comestível/crescimento & desenvolvimento , Fósseis , Agricultura/métodos , Animais , Osso e Ossos/anatomia & histologia , Chipre , Geografia , História Antiga , Hordeum/crescimento & desenvolvimento , Humanos , Datação Radiométrica , Dente/anatomia & histologia , Triticum/crescimento & desenvolvimento
3.
Rapid Commun Mass Spectrom ; 24(5): 605-12, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20155761

RESUMO

Evidence is growing that the range of zinc stable isotope compositions, represented by the deviation of (66)Zn in permil units relative to a standard and expressed as delta(66)Zn, is larger in organic matter than in inorganic material. This study reports the variations of delta(66)Zn in various organs of sheep raised on a controlled diet. Zinc was purified by anion-exchange chromatography. The Zn concentrations and Zn stable isotope compositions were determined by quadrupole inductively coupled plasma mass spectrometry and multi-collector inductively coupled plasma mass spectrometry, respectively. The data show that delta(66)Zn variability exceeds 1 per thousand, with bone, muscle, serum and urine enriched in the heavy isotopes, and feces, red blood cells, kidney and liver enriched in light isotopes, all relative to the diet value. The (66)Zn enrichment of the circulating serum reservoir is likely to take place in the digestive tract, probably through the preferential binding of lighter isotopes with phytic acid, which is known to control the uptake of metallic elements. Mass balance calculations suggest that the (66)Zn depletion between diet and feces, which is not balanced by any other outward flux, leads to a secular isotopic drift in serum. A simple time-dependent two-box model, involving the gastro-intestinal tract on the one hand and the muscle and bone on the other, predicts that the maximum (66)Zn enrichment, which equals the difference in delta(66)Zn between diet and bulk (approximately 0.25 per thousand), is reached after about ten years. Therefore, a better understanding of the variations of natural abundance of Zn isotopes in animals and humans will probably bring new perspectives for the assessment of their Zn status.


Assuntos
Espectrometria de Massas/métodos , Ovinos/metabolismo , Isótopos de Zinco/análise , Zinco/análise , Ração Animal/análise , Animais , Líquidos Corporais/química , Cromatografia por Troca Iônica/métodos , Fezes/química , Alimentos Fortificados/análise , Estatísticas não Paramétricas , Distribuição Tecidual
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