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The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease.
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Evolución Biológica , Ecología/métodos , Hominidae/microbiología , Metagenoma/genética , Microbiota/genética , Boca/microbiología , África , Animales , Bacterias/clasificación , Bacterias/genética , Biopelículas , Placa Dental/microbiología , Geografía , Gorilla gorilla/microbiología , Hominidae/clasificación , Humanos , Pan troglodytes/microbiología , FilogeniaRESUMEN
Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. Here we analyse genome-wide data from 51 Eurasians from ~45,000-7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3-6% to around 2%, consistent with natural selection against Neanderthal variants in modern humans. Whereas there is no evidence of the earliest modern humans in Europe contributing to the genetic composition of present-day Europeans, all individuals between ~37,000 and ~14,000 years ago descended from a single founder population which forms part of the ancestry of present-day Europeans. An ~35,000-year-old individual from northwest Europe represents an early branch of this founder population which was then displaced across a broad region, before reappearing in southwest Europe at the height of the last Ice Age ~19,000 years ago. During the major warming period after ~14,000 years ago, a genetic component related to present-day Near Easterners became widespread in Europe. These results document how population turnover and migration have been recurring themes of European prehistory.
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Cubierta de Hielo , Población Blanca/genética , Población Blanca/historia , Animales , Evolución Biológica , ADN/análisis , ADN/genética , ADN/aislamiento & purificación , Europa (Continente) , Femenino , Efecto Fundador , Genética de Población , Historia Antigua , Migración Humana/historia , Humanos , Masculino , Medio Oriente , Hombre de Neandertal/genética , Filogenia , Dinámica Poblacional , Selección Genética , Análisis de Secuencia de ADN , Factores de TiempoRESUMEN
In the last few decades, the field of ancient DNA has taken a new direction towards using sedimentary ancient DNA (sedaDNA) for studying human and mammalian population dynamics as well as past ecosystems. However, the screening of numerous sediment samples from archaeological sites remains a time-consuming and costly endeavor, particularly when targeting hominin DNA. Here, we present a novel high-throughput method that facilitates the fast and efficient analysis of sediment samples by applying a pooled testing approach. This method combines multiple extracts, enabling early parallelization of laboratory procedures and effective aDNA screening. Pooled samples with detectable aDNA signals undergo detailed analysis, while empty pools are discarded. We have successfully applied our method to multiple sediment samples from Middle and Upper Paleolithic sites in Europe, Asia, and Africa. Notably, our results reveal that an aDNA signal remains discernible even when pooled with four negative samples. We also demonstrate that the DNA yield of double-stranded libraries increases significantly when reducing the extract input, potentially mitigating the effects of inhibition. By embracing this innovative approach, researchers can analyze large numbers of sediment samples for aDNA preservation, achieving significant cost reductions of up to 70% and reducing hands-on laboratory time to one-fifth.
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ADN Antiguo , Sedimentos Geológicos , ADN Antiguo/análisis , Humanos , Animales , Arqueología/métodos , Fósiles , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hominidae/genética , Europa (Continente) , ÁfricaRESUMEN
The Pleistocene was an epoch of extreme climatic and environmental changes. How individual species responded to the repeated cycles of warm and cold stages is a major topic of debate. For the European fauna and flora, an expansion-contraction model has been suggested, whereby temperate species were restricted to southern refugia during glacial times and expanded northwards during interglacials, including the present interglacial (Holocene). Here, we test this model on the red deer (Cervus elaphus) a large and highly mobile herbivore, using both modern and ancient mitochondrial DNA from the entire European range of the species over the last c. 40,000 years. Our results indicate that this species was sensitive to the effects of climate change. Prior to the Last Glacial Maximum (LGM) haplogroups restricted today to South-East Europe and Western Asia reached as far west as the UK. During the LGM, red deer was mainly restricted to southern refugia, in Iberia, the Balkans and possibly in Italy and South-Western Asia. At the end of the LGM, red deer expanded from the Iberian refugium, to Central and Northern Europe, including the UK, Belgium, Scandinavia, Germany, Poland and Belarus. Ancient DNA data cannot rule out refugial survival of red deer in North-West Europe through the LGM. Had such deer survived, though, they were replaced by deer migrating from Iberia at the end of the glacial. The Balkans served as a separate LGM refugium and were probably connected to Western Asia with genetic exchange between the two areas.
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Cambio Climático , Ciervos/genética , Genética de Población , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Europa (Continente) , Variación Genética , Haplotipos , Funciones de Verosimilitud , Datos de Secuencia Molecular , Filogenia , Filogeografía , Datación Radiométrica , Análisis de Secuencia de ADNRESUMEN
Despite being one of the most important crops in the recent prehistory of Eurasia, the arrival and exploitation of millets in the westernmost part of Europe are still largely underexplored. Here and for the first time, we report multipronged biomolecular evidence of millet consumption along the Atlantic façade of northern Iberia through a combination of radiocarbon dating, stable isotopes, and dental calculus analyses on the human individuals found in the burial site of El Espinoso cave (Asturias, Spain). The high-resolution chronological framework established for individuals placed the burials between 1235 and 1099 cal. BC. The discovery of high δ13C values on their bone collagen and the identification of polyhedral starch grains within their dental plaque underline the relevance of C4 plants in their diet and highlights the timing of the systematic consumption of millets in the Late Bronze Age. Our data support previous regional archaeobotanical evidence and establish a more precise chronology of the dispersal of millets into northern Iberia during the Bronze Age, becoming an essential crop until the arrival of maize from America after AD 1492. This study emphasizes the importance of multidisciplinary methods to ascertain the origin and development of agricultural practices during recent prehistory.
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Arqueología , Mijos , Humanos , Datación Radiométrica , Grano Comestible , Productos AgrícolasRESUMEN
Prehistoric shell middens hold valuable evidence of past human-environment interactions. In this study, we used carbon (δ13C) and oxygen (δ18O) stable isotopes of Mytilus galloprovincialis shells excavated from El Perro, La Fragua and La Chora, three Mesolithic middens in Cantabria, Northern Spain, to examine hunter-gatherer subsistence strategies in terms of seasonality and collection areas. Furthermore, we used shell δ18O to reconstruct water temperature during the early Holocene. Stable isotopes reveal a shellfish harvesting diversification trend represented by the gradual establishment of the upper estuaries as new procurement areas and an increase of harvesting mobility in both coastal and in-land sites. These innovations in subsistence strategies during the Mesolithic coincided with major changes in the surrounding environment as attested by the water temperature reconstructions based on δ18O and backed by several global and regional records. Overall, our results show that shell δ13C and δ18O stable isotopes have an underexplored potential as provenance proxies which stimulates their application to the archaeological record to further understand prehistoric human resource procurement and diet.
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The cooling and drying associated with the so-called '8.2 ka event' have long been hypothesized as having sweeping implications for human societies in the Early Holocene, including some of the last Mesolithic hunter-gatherers in Atlantic Europe. Nevertheless, detailed 'on-site' records with which the impacts of broader climate changes on human-relevant environments can be explored have been lacking. Here, we reconstruct sea surface temperatures (SST) from δ18O values measured on subfossil topshells Phorcus lineatus exploited by the Mesolithic human groups that lived at El Mazo cave (N Spain) between 9 and 7.4 ka. Bayesian modelling of 65 radiocarbon dates, in combination with this δ18O data, provide a high-resolution seasonal record of SST, revealing that colder SST during the 8.2 ka event led to changes in the availability of different shellfish species. Intensification in the exploitation of molluscs by humans indicates demographic growth in these Atlantic coastal settings which acted as refugia during this cold event.
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Cambio Climático , Hominidae , Animales , Teorema de Bayes , Cuevas , Europa (Continente) , HumanosRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0194708.].
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Methodological advances in dating the Middle to Upper Paleolithic transition provide a better understanding of the replacement of local Neanderthal populations by Anatomically Modern Humans. Today we know that this replacement was not a single, pan-European event, but rather it took place at different times in different regions. Thus, local conditions could have played a role. Iberia represents a significant macro-region to study this process. Northern Atlantic Spain contains evidence of both Mousterian and Early Upper Paleolithic occupations, although most of them are not properly dated, thus hindering the chances of an adequate interpretation. Here we present 46 new radiocarbon dates conducted using ultrafiltration pre-treatment method of anthropogenically manipulated bones from 13 sites in the Cantabrian region containing Mousterian, Aurignacian and Gravettian levels, of which 30 are considered relevant. These dates, alongside previously reported ones, were integrated into a Bayesian age model to reconstruct an absolute timescale for the transitional period. According to it, the Mousterian disappeared in the region by 47.9-45.1ka cal BP, while the Châtelperronian lasted between 42.6k and 41.5ka cal BP. The Mousterian and Châtelperronian did not overlap, indicating that the latter might be either intrusive or an offshoot of the Mousterian. The new chronology also suggests that the Aurignacian appears between 43.3-40.5ka cal BP overlapping with the Châtelperronian, and ended around 34.6-33.1ka cal BP, after the Gravettian had already been established in the region. This evidence indicates that Neanderthals and AMH co-existed <1,000 years, with the caveat that no diagnostic human remains have been found with the latest Mousterian, Châtelperronian or earliest Aurignacian in Cantabrian Spain.
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The chemical composition of mollusk shells offers information about environmental conditions present during the lifespan of the organism. Shells found in geological deposits and in many archeological sites can help to reconstruct past climatic conditions. For example, a correlation has been found between seawater temperature and the amount of some substituent elements (e.g., magnesium, strontium) in the biogenerated calcium carbonate matrix of the shell, although it is very species-specific. Here we propose the use laser-induced breakdown spectroscopy (LIBS) to estimate Mg/Ca ratios in modern specimens of the common limpet Patella vulgata. An automated setup was used to obtain a sequence of Mg/Ca ratios across a sampling path that could be compared with the seawater temperatures recorded during the organism's lifespan. Results using four shells collected in different months of the year showed a direct relationship between the Mg/Ca ratios and the seawater temperature, although the sequences also revealed small-scale (short-term) variability and an irregular growth rate. Nevertheless, it was possible to infer the season of capture and the minimum and maximum seawater temperatures from the LIBS sequences. This fact, along with the reduction in sampling and measurement time compared with other spectrometric techniques (such as inductively coupled plasma mass spectrometry [ICP-MS]), makes LIBS useful in paleoclimatic studies.
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Exoesqueleto/química , Calcio/análisis , Gastrópodos/química , Magnesio/análisis , Paleontología/métodos , Análisis Espectral/métodos , Animales , Clima , Límite de Detección , Modelos Lineales , Reproducibilidad de los ResultadosRESUMEN
Se refieren los casos de ocno pacientes adultos con púrpura trombocitopénica amegacariocítica adquirida (PTAA); uno de ellos fue considerado como idiopático y siete estuvieron asociados con diversos agentes: insecticidas, sedantes, agua quina, tolbutamida, sulfas, alcohol, pirazolonas y azulfidina. Dos casos tuvieron recurrencias de la PTAA: uno hasta siete veces con el insecticida y otro en una ocasión más, al ingerir bebidas preparadas con agua quina. De los siete pacientes con PTAA asociada a drogas, cuatro tuvieron remisiones de la trombocitopenia, que fueron espontáneas o "inducidas" con prednisona y esplenectomía. Se hacem algunas consideraciones en cuanto a la etiopatogenia y el tratamiento de este raro síndrome