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OBJECTIVES: To investigate approaches of reasoning with large language models (LLMs) and to propose a new prompting approach, ensemble reasoning, to improve medical question answering performance with refined reasoning and reduced inconsistency. MATERIALS AND METHODS: We used multiple choice questions from the USMLE Sample Exam question files on 2 closed-source commercial and 1 open-source clinical LLM to evaluate our proposed approach ensemble reasoning. RESULTS: On GPT-3.5 turbo and Med42-70B, our proposed ensemble reasoning approach outperformed zero-shot chain-of-thought with self-consistency on Steps 1, 2, and 3 questions (+3.44%, +4.00%, and +2.54%) and (2.3%, 5.00%, and 4.15%), respectively. With GPT-4 turbo, there were mixed results with ensemble reasoning again outperforming zero-shot chain-of-thought with self-consistency on Step 1 questions (+1.15%). In all cases, the results demonstrated improved consistency of responses with our approach. A qualitative analysis of the reasoning from the model demonstrated that the ensemble reasoning approach produces correct and helpful reasoning. CONCLUSION: The proposed iterative ensemble reasoning has the potential to improve the performance of LLMs in medical question answering tasks, particularly with the less powerful LLMs like GPT-3.5 turbo and Med42-70B, which may suggest that this is a promising approach for LLMs with lower capabilities. Additionally, the findings show that our approach helps to refine the reasoning generated by the LLM and thereby improve consistency even with the more powerful GPT-4 turbo. We also identify the potential and need for human-artificial intelligence teaming to improve the reasoning beyond the limits of the model.
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Procesamiento de Lenguaje Natural , Humanos , Evaluación Educacional/métodosRESUMEN
Tell Kamid el-Loz (Lebanon) was an important Bronze Age urban center that dominated one of the central crossroads of the Ancient Near East, connecting Egypt and the Levant with northern Mesopotamia, Anatolia, and Syria, as well as the interior with the Mediterranean coast. However, by the early Iron Age, the site had shrunk to a small rural settlement. Later, in the Iron Age III / Persian-Hellenistic, only enigmatic pits and a large cemetery remained. In this paper, we analyzed plant micro-remains from the dental calculus of 15 individuals (3 from the Middle Bronze Age II and 12 from the Iron Age III / Persian-Hellenistic) and δ 13C and δ 15N stable isotope data from tbulk bone collagen of 74 individuals (10 from the Middle Bronze Age II and 64 from the Iron Age III / Persian-Hellenistic) and 13 Late Bronze Age animal bones (7 Ovis/Capra and 6 Bos). Our results indicate general stability of human diet throughout the Middle Bronze Age II and the Iron III / Persian-Hellenistic periods, with a reliance on C3 plant crops and terrestrial animals also consuming C3 plants. In the later period, the plant micro-remains indicate the consumption of C4 plants and sedges, and the stable isotope analysis indicates differences in diet between males and females. Supplementary Information: The online version contains supplementary material available at 10.1007/s12520-024-02000-w.
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The ancient city of Chichén Itzá in Yucatán, Mexico, was one of the largest and most influential Maya settlements during the Late and Terminal Classic periods (AD 600-1000) and it remains one of the most intensively studied archaeological sites in Mesoamerica1-4. However, many questions about the social and cultural use of its ceremonial spaces, as well as its population's genetic ties to other Mesoamerican groups, remain unanswered2. Here we present genome-wide data obtained from 64 subadult individuals dating to around AD 500-900 that were found in a subterranean mass burial near the Sacred Cenote (sinkhole) in the ceremonial centre of Chichén Itzá. Genetic analyses showed that all analysed individuals were male and several individuals were closely related, including two pairs of monozygotic twins. Twins feature prominently in Mayan and broader Mesoamerican mythology, where they embody qualities of duality among deities and heroes5, but until now they had not been identified in ancient Mayan mortuary contexts. Genetic comparison to present-day people in the region shows genetic continuity with the ancient inhabitants of Chichén Itzá, except at certain genetic loci related to human immunity, including the human leukocyte antigen complex, suggesting signals of adaptation due to infectious diseases introduced to the region during the colonial period.
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Conducta Ceremonial , ADN Antiguo , Genoma Humano , Humanos , México , Genoma Humano/genética , Masculino , ADN Antiguo/análisis , Historia Antigua , Femenino , Entierro/historia , Arqueología , Gemelos/genética , Historia MedievalRESUMEN
Susceptibility to morbidity and mortality is increased in early life, yet proactive measures, such as breastfeeding and weaning practices, can be taken through specific investments from parents and wider society. The extent to which such biosocialcultural investment was achieved within 1st millennium BCE Etruscan society, of whom little written sources are available, is unkown. This research investigates life histories in non-adults and adults from Pontecagnano (southern Italy, 730-580 BCE) in order to track cross-sectional and longitudinal breastfeeding and weaning patterns and to characterize the diet more broadly. Stable carbon and nitrogen isotope analysis of incrementally-sampled deciduous and permanent dentine (n = 15), bulk bone collagen (n = 38), and tooth enamel bioapatite (n = 21) reveal the diet was largely based on C3 staple crops with marginal contributions of animal protein. Millet was found to play a role for maternal diet and trajectories of breastfeeding and feeding for some infants and children at the site. The combination of multiple isotope systems and tissues demonstrates exclusive breastfeeding was pursued until 0.6 years, followed by progressive introduction of proteanocius supplementary foods during weaning that lasted between approximately 0.7 and 2.6 years. The combination of biochemical data with macroscopic skeletal lesions of infantile metabolic diseases and physiological stress markers showed high δ15Ndentine in the months prior to death consistent with the isotopic pattern of opposing covariance.
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Huesos , Isótopos de Carbono , Dieta , Isótopos de Nitrógeno , Humanos , Italia , Lactante , Dieta/historia , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Historia Antigua , Huesos/química , Femenino , Paleopatología , Adulto , Destete , Lactancia Materna/historia , Estrés Fisiológico , Dentina/química , Dentina/metabolismo , Colágeno/metabolismo , Colágeno/análisis , Preescolar , Masculino , NiñoRESUMEN
Medieval Iberia witnessed the complex negotiation of religious, social, and economic identities, including the formation of religious orders that played a major role in border disputes and conflicts. While archival records provide insights into the compositions of these orders, there have been few direct dietary or osteoarchaeological studies to date. Here, we analysed 25 individuals discovered at the Zorita de los Canes Castle church cemetery, Guadalajara, Spain, where members of one of the first religious orders, the Order of Calatrava knights, were buried between the 12th to 15th centuries CE. Stable carbon (δ13C) and nitrogen (δ15N) isotope analyses of bone collagen reveal dietary patterns typical of the Medieval social elite, with the Bayesian R model, 'Simmr' suggesting a diet rich in poultry and marine fish in this inland population. Social comparisons and statistical analyses further support the idea that the order predominantly comprised the lower nobility and urban elite in agreement with historical sources. Our study suggests that while the cemetery primarily served the order's elite, the presence of individuals with diverse dietary patterns may indicate complexities of temporal use or wider social interaction of the medieval military order.
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Isótopos de Carbono , Isótopos de Nitrógeno , Humanos , España , Historia Medieval , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Huesos/química , Arqueología , Personal Militar/historia , Dieta/historia , Masculino , Femenino , Clase Social/historia , Cementerios/historia , Colágeno/análisis , Teorema de BayesRESUMEN
Interpretations of Late Pleistocene hominin adaptative capacities by archaeologists have focused heavily on their exploitation of certain prey and documented contemporary behaviours for these species. However, we cannot assume that animal prey-taxa ecology and ethology were the same in the past as in the present, or were constant over archaeological timescales. Sequential isotope analysis of herbivore teeth has emerged as a particularly powerful method of directly reconstructing diet, ecology and mobility patterns on sub-annual scales. Here, we apply 87Sr/86Sr isotope analysis, in combination with δ18O and δ13C isotope analysis, to sequentially sampled tooth enamel of prevalent herbivore species that populated Europe during the Last Glacial Period, including Rangifer tarandus, Equus sp. and Mammuthus primigenius. Our samples come from two open-air archaeological sites in Central Germany, Königsaue and Breitenbach, associated with Middle Palaeolithic and early Upper Palaeolithic cultures, respectively. We identify potential inter- and intra-species differences in range size and movement through time, contextualised through insights into diet and the wider environment. However, homogeneous bioavailable 87Sr/86Sr across large parts of the study region prevented the identification of specific migration routes. Finally, we discuss the possible influence of large-herbivore behaviour on hominin hunting decisions at the two sites.
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Isótopos de Carbono , Herbivoria , Animales , Isótopos de Carbono/análisis , Fósiles , Hominidae/fisiología , Isótopos de Estroncio/análisis , Arqueología , Europa (Continente) , Migración Animal , Esmalte Dental/química , Dieta , Alemania , Isótopos de Oxígeno/análisisRESUMEN
The Bronze Age of Central Europe was a period of major social, economic, political and ideological change. The arrival of millet is often seen as part of wider Bronze Age connectivity, yet understanding of the subsistence regimes underpinning this dynamic period remains poor for this region, in large part due to a dominance of cremation funerary rites, which hinder biomolecular studies. Here, we apply stable isotope analysis, radiocarbon dating and archaeobotanical analysis to two Late Bronze Age (LBA) sites, Esperstedt and Kuckenburg, in central Germany, where human remains were inhumed rather than cremated. We find that people buried at these sites did not consume millet before the Middle Bronze Age (MBA) (ca. 1600 BCE). However, by the early LBA (ca. 1300-1050 BCE) people consumed millet, often in substantial quantities. This consumption appears to have subsequently diminished or ceased around 1050-800 BCE, despite charred millet grains still being found in the archaeological deposits from this period. The arrival of millet in this region, followed by a surge in consumption spanning two centuries, indicates a complex interplay of cultural and economic factors, as well as a potential use of millet to buffer changes in aridity in a region increasingly prone to crop failure in the face of climate change today.
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Arqueología , Mijos , Humanos , Europa (Continente) , Alemania , Isótopos de Carbono/análisisRESUMEN
The largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki1, persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct2-4. Its demise is enigmatic considering that it was one of the few Asian great apes to go extinct in the last 2.6 million years, whereas others, including orangutan, survived until the present5. The cause of the disappearance of G. blacki remains unresolved but could shed light on primate resilience and the fate of megafauna in this region6. Here we applied three multidisciplinary analyses-timing, past environments and behaviour-to 22 caves in southern China. We used 157 radiometric ages from six dating techniques to establish a timeline for the demise of G. blacki. We show that from 2.3 million years ago the environment was a mosaic of forests and grasses, providing ideal conditions for thriving G. blacki populations. However, just before and during the extinction window between 295,000 and 215,000 years ago there was enhanced environmental variability from increased seasonality, which caused changes in plant communities and an increase in open forest environments. Although its close relative Pongo weidenreichi managed to adapt its dietary preferences and behaviour to this variability, G. blacki showed signs of chronic stress and dwindling populations. Ultimately its struggle to adapt led to the extinction of the greatest primate to ever inhabit the Earth.
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Extinción Biológica , Fósiles , Hominidae , Animales , Cuevas , China , Dieta/veterinaria , Bosques , Hominidae/clasificación , Plantas , Pongo , Datación Radiométrica , Estaciones del Año , Factores de TiempoRESUMEN
The insular region of Wallacea has become a focal point for studying Pleistocene human ecological and cultural adaptations in island environments, however, little is understood about early burial traditions during the Pleistocene. Here we investigate maritime interactions and burial practices at Ratu Mali 2, an elevated coastal cave site on the small island of Kisar in the Lesser Sunda Islands of eastern Indonesia dated to 15,500-3700 cal. BP. This multidisciplinary study demonstrates extreme marine dietary adaptations, engagement with an extensive exchange network across open seas, and early mortuary practices. A flexed male and a female, interred in a single grave with abundant shellfish and obsidian at Ratu Mali 2 by 14.7 ka are the oldest known human burials in Wallacea with established funerary rites. These findings highlight the impressive flexibility of our species in marginal environments and provide insight into the earliest known ritualised treatment of the dead in Wallacea.
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Arqueología , Entierro , Humanos , Masculino , Femenino , Indonesia , Cuevas , Prácticas MortuoriasRESUMEN
OBJECTIVE: Investigate disparities in retinal vein occlusion (RVO) presentation and initiation of anti-VEGF treatment. DESIGN: Retrospective cohort study. SUBJECTS: Patients in the American Academy of Ophthalmology IRIS® (Intelligent Research in Sight) Registry database (2015-2021) with branch or central RVO and macular edema (ME). METHODS: The association of demographic characteristics and presenting visual acuity (VA) with anti-VEGF treatment initiation were quantified using multivariable logistic regression. MAIN OUTCOME MEASURES: Treatment with ≥ 1 anti-VEGF injection within 12 months after RVO diagnosis. RESULTS: A total of 304 558 eligible patients with RVO and ME were identified. Age at presentation varied by race, ethnicity, sex, and RVO type (all P values < 0.001). Within the first year after RVO presentation, 192 602 (63.2%) patients received ≥ 1 anti-VEGF injection. In a multivariable regression model adjusting for relevant covariates, female (vs. male) patients had lower odds of receiving injections (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.93-0.96; P < 0.0001) as did Black/African American (vs. White) patients (OR, 0.90; 95% CI, 0.88-0.92; P < 0.0001) and Asian (vs. White) patients (OR, 0.95; 95% CI, 0.91-0.99; P = 0.02), whereas older patients (vs. patients aged < 51 years) had higher odds (61-70 years: OR, 1.20; 95% CI, 1.16-1.24; 71-80 years: OR, 1.20; 95% CI, 1.16-1.24; > 80 years: OR, 1.15; 95% CI, 1.11-1.18; all P values < 0.0001). Hispanic (vs. non-Hispanic) patients had a small increased odds of treatment initiation (OR, 1.08; 95% CI, 1.04-1.11; P < 0.0001). Results were similar in the subset of 226 143 patients with VA data. In this subset, patients with presenting VA < 20/40 to 20/200 were most frequently treated in the first year after diagnosis (â¼ 70%) and patients with light perception/no light perception (LP-NLP) vision or VA of 20/20 or better were treated least frequently (36.9% and 41.9%, respectively). CONCLUSIONS: In this large national clinical registry, 37% of RVO patients with ME had no anti-VEGF treatment documented in the first year after diagnosis. Black/African American, Asian, and female patients and patients with VA of LP-NLP were least likely to receive treatment. Awareness of this undertreatment and these disparities highlight the need for initiatives to ensure all RVO patients receive timely anti-VEGF injections for optimized visual outcomes. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Inhibidores de la Angiogénesis , Inyecciones Intravítreas , Sistema de Registros , Oclusión de la Vena Retiniana , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual , Humanos , Oclusión de la Vena Retiniana/tratamiento farmacológico , Oclusión de la Vena Retiniana/diagnóstico , Femenino , Masculino , Estudios Retrospectivos , Inhibidores de la Angiogénesis/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Anciano , Persona de Mediana Edad , Bevacizumab/administración & dosificación , Academias e Institutos , Estados Unidos/epidemiología , Tomografía de Coherencia Óptica/métodos , Estudios de Seguimiento , Ranibizumab/administración & dosificación , Receptores de Factores de Crecimiento Endotelial Vascular/administración & dosificación , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Anciano de 80 o más AñosRESUMEN
The introduction of domestic horses transformed Indigenous societies across the grasslands of Argentina, leading to the emergence of specialized horse cultures across the Southern Cone. However, the dynamics of this introduction are poorly chronicled by historic records. Here, we apply archaeozoological and biomolecular techniques to horse remains from the site of Chorrillo Grande 1 in southern Argentina. Osteological and taphonomic analyses suggest that horses were pastorally managed and used for food by Aónikenk/Tehuelche hunter-gatherers before the onset of permanent European settlement, as early as the mid-17th century. DNA-based sex identifications suggest consumption of both male and female horses, while ceramic residue also shows use of guanaco products. Sequential isotope analyses on horse dentition reveal an origin in southern Patagonia and movement of these animals between the Río Coig and Río Gallegos basins. These results reinforce emerging evidence for rapid Indigenous-mediated dispersal of horses in the Americas and demonstrate that horses catalyzed rapid economic and social transformations.
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Alimentos , Animales , Caballos , Masculino , Femenino , ArgentinaRESUMEN
As one of the key, long-term occupied sites in the Southern Levant, Jericho was one of the most important early Neolithic centres to witness social and economic changes associated with the domestication of plants and animals. This study applies strontium (87Sr/86Sr), oxygen (δ18O) and carbon (δ13C) isotope analyses to the enamel of 52 human teeth from Pre-Pottery Neolithic (PPN) layers of Jericho to directly study human diet and mobility and investigate the degree of consolidation and the flexibility of social organization of Jericho society in the PPN period. The results indicate only two non-local individuals out of the 44 sampled inhabitants identified by strontium isotope analysis and are consistent with the presence of a largely sedentary community at PPN Jericho with no evidence for large-scale migration. We also construct strontium spatial baselines (87Sr/86Sr map) with local 87Sr/86Sr signatures for the sites across the Southern Levant based on systematic compilation and analysis of available data. In addition, we apply proteomic analysis of sex-specific amelogenin peptides in tooth enamel for sex estimation of the sampled individuals (n = 44), the results of which showed a sex-biased ratio (more male than female detected in this sample pool) in Jericho society during the PPN period, which may be due to the limited sample size or selective ritual practices like particular burial zones used for specific groups. We also pretreated a batch of human bone samples recovered from PPNB Jericho for stable carbon and nitrogen isotope analyses for dietary investigations. However, the extracted collagen showed poor preservation and no valid δ13C or δ15N data were obtained.
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Proteómica , Diente , Humanos , Masculino , Animales , Femenino , Diente/química , Isótopos de Estroncio/análisis , Entierro , CarbonoRESUMEN
The horse is central to many Indigenous cultures across the American Southwest and the Great Plains. However, when and how horses were first integrated into Indigenous lifeways remain contentious, with extant models derived largely from colonial records. We conducted an interdisciplinary study of an assemblage of historic archaeological horse remains, integrating genomic, isotopic, radiocarbon, and paleopathological evidence. Archaeological and modern North American horses show strong Iberian genetic affinities, with later influx from British sources, but no Viking proximity. Horses rapidly spread from the south into the northern Rockies and central plains by the first half of the 17th century CE, likely through Indigenous exchange networks. They were deeply integrated into Indigenous societies before the arrival of 18th-century European observers, as reflected in herd management, ceremonial practices, and culture.
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Animales Domésticos , Domesticación , Caballos , Animales , Humanos , Arqueología , Estados UnidosRESUMEN
The Ihò Eléérú (or Iho Eleru) rock shelter, located in Southwest Nigeria, is the only site from which Pleistocene-age hominin fossils have been recovered in western Africa. Excavations at Iho Eleru revealed regular human occupations ranging from the Later Stone Age (LSA) to the present day. Here, we present chronometric, archaeobotanical, and paleoenvironmental findings, which include the taxonomic, taphonomic, and isotopic analyses of what is the only Pleistocene faunal assemblage documented in western Africa. Our results indicate that the local landscape surrounding Iho Eleru, although situated within a regional open-canopy biome, was forested throughout the past human occupation of the site. At a regional scale, a shift from forest- to savanna-dominated ecotonal environment occurred during a mid-Holocene warm event 6,000 years ago, with a subsequent modern reforestation of the landscape. Locally, no environmental shift was observable, placing Iho Eleru in a persistent forested "island" during the period of occupation.
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Growing reliance on animal and plant domestication in the Near East and beyond during the Pre-Pottery Neolithic B (PPNB) (the ninth to eighth millennium BC) has often been associated with a "revolutionary" social transformation from mobility toward more sedentary lifestyles. We are able to yield nuanced insights into the process of the Neolithization in the Near East based on a bioarchaeological approach integrating isotopic and archaeogenetic analyses on the bone remains recovered from Nevali Çori, a site occupied from the early PPNB in Turkey where some of the earliest evidence of animal and plant domestication emerged, and from Ba'ja, a typical late PPNB site in Jordan. In addition, we present the archaeological sequence of Nevali Çori together with newly generated radiocarbon dates. Our results are based on strontium (87Sr/86Sr), carbon, and oxygen (δ18O and δ13Ccarb) isotopic analyses conducted on 28 human and 29 animal individuals from the site of Nevali Çori. 87Sr/86Sr results indicate mobility and connection with the contemporaneous surrounding sites during the earlier PPNB prior to an apparent decline in this mobility at a time of growing reliance on domesticates. Genome-wide data from six human individuals from Nevali Çori and Ba'ja demonstrate a diverse gene pool at Nevali Çori that supports connectedness within the Fertile Crescent during the earlier phases of Neolithization and evidence of consanguineous union in the PPNB Ba'ja and the Iron Age Nevali Çori.
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Carbono , Domesticación , Animales , Humanos , Historia Antigua , Turquía , Jordania , Arqueología , ADNRESUMEN
In western and north-western Europe there has been a growing focus on exploring how major economic, political, and social changes during the Medieval period impacted the lived experience of different populations and sectors of society. Stable isotope analysis has proven particularly powerful in this regard, providing direct insights into the long-term diets of individuals and communities. Despite experiencing similarly dramatic social reconfigurations and changes, eastern Europe has, however, received far less attention in this regard. The territory of Belarus has, especially, so far remained a relative blank spot on the bioarchaeological map of Europe, though cities such as Polack emerged rapidly as key nodes within a growing economic and religious network. To gain direct insight into the diets of inhabitants of the Polack region of Belarus in the 11-18th centuries, we applied stable carbon and nitrogen isotope analysis to bone and dentine collagen from human (n = 143) and animal (n = 105) individuals from the city of Polack and surrounding rural sites. Results indicate a diet based on C3 terrestrial resources, which did not differ between sexes and showed limited variation over time. Contrary to expectations, it appears that animal products were commonly consumed by rural dwellers, but no significant reliance on fish resources or millet consumption is found. In contrast to examples from western Europe, we argue that the diets in the city and the surrounding villages remained broadly similar for the majority of the population, and similar to commoners analysed in Poland and Lithuania, perhaps suggestive of slightly different economic changes operating in this part of the Medieval world.
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Colágeno , Dieta , Animales , Carbono , Isótopos de Carbono/análisis , Dieta/historia , Historia Medieval , Humanos , Isótopos de Nitrógeno/análisis , Polonia , República de BelarúsRESUMEN
Although once considered a 'counterfeit paradise', the Amazon Basin is now a region of increasing interest in discussions of pre-colonial tropical land-use and social complexity. Archaeobotany, archaeozoology, remote sensing and palaeoecology have revealed that, by the Late Holocene, populations in different parts of the Amazon Basin were using various domesticated plants, modifying soils, building earthworks, and even forming 'Garden Cities' along the Amazon River and its tributaries. However, there remains a relatively limited understanding as to how diets, environmental management, and social structures varied across this vast area. Here, we apply stable isotope analysis to human remains (n = 4 for collagen, n = 17 for tooth enamel), and associated fauna (n = 61 for collagen, n = 28 for tooth enamel), to directly determine the diets of populations living in the Volta Grande do Rio Xingu, an important region of pre-Columbian cultural interactions, between 390 cal. years BC and 1,675 cal. years AD. Our results highlight an ongoing dietary focus on C3 plants and wild terrestrial fauna and aquatic resources across sites and time periods, with varying integration of C4 plants (i.e. maize). We argue that, when compared to other datasets now available from elsewhere in the Amazon Basin, our study highlights the development of regional adaptations to local watercourses and forest types.
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Isótopos , Ríos , Colágeno , Dieta , Bosques , Humanos , Ríos/químicaRESUMEN
RATIONALE: Dental calculus (mineralised dental plaque) is composed primarily of hydroxyapatite. We hypothesise that the carbonate component of dental calculus will reflect the isotopic composition of ingested simple carbohydrates. Therefore, dental calculus carbonates may be an indicator for sugar consumption, and an alternative to bone carbonate in isotopic palaeodiet studies. METHODS: We utilised Fourier transform infrared attenuated total reflectance analysis to characterise the composition and crystallisation of bone and dental calculus before isotope analysis of carbonate. Using a Sercon 20-22 mass spectrometer coupled with a Sercon GSL sample preparation system and an IsoPrime 100 dual inlet mass spectrometer plus Multiprep device to measure carbon, we tested the potential of dental calculus carbonate to identify C4 resources in diet through analysis of δ13 C values in paired bone, calculus and teeth mineral samples. RESULTS: The modern population shows higher δ13 C values in all three tissue carbonates compared to both archaeological populations. Clear differences in dental calculus δ13 C values are observed between the modern and archaeological individuals suggesting potential for utilising dental calculus in isotope palaeodiet studies. The offset between dental calculus and either bone or enamel carbonate δ13 C values is large and consistent in direction, with no consistent offset between the δ13 C values for the three tissues per individual. CONCLUSIONS: Our results support dental calculus carbonate as a new biomaterial to identify C4 sugar through isotope analysis. Greater carbon fractionation in the mouth is likely due to the complex formation of dental calculus as a mineralized biofilm, which results in consistently high δ13 C values compared to bone and enamel.
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Cálculos Dentales , Azúcares , Carbono , Isótopos de Carbono/análisis , Carbonatos/análisis , Azúcares de la Dieta , Humanos , Isótopos/análisisRESUMEN
Oceania is a key region for studying human dispersals, adaptations and interactions with other hominin populations. Although archaeological evidence now reveals occupation of the region by approximately 65-45 000 years ago, its human fossil record, which has the best potential to provide direct insights into ecological adaptations and population relationships, has remained much more elusive. Here, we apply radiocarbon dating and stable isotope approaches to the earliest human remains so far excavated on the islands of Near and Remote Oceania to explore the chronology and diets of the first preserved human individuals to step across these Pacific frontiers. We demonstrate that the oldest human (or indeed hominin) fossil outside of the mainland New Guinea-Aru area dates to approximately 11 800 years ago. Furthermore, although these early sea-faring populations have been associated with a specialized coastal adaptation, we show that Late Pleistocene-Holocene humans living on islands in the Bismarck Archipelago and in Vanuatu display a persistent reliance on interior tropical forest resources. We argue that local tropical habitats, rather than purely coasts or, later, arriving domesticates, should be emphasized in discussions of human diets and cultural practices from the onset of our species' arrival in this part of the world. This article is part of the theme issue 'Tropical forests in the deep human past'.
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Fósiles , Hominidae , Animales , Peces , Bosques , Humanos , Oceanía , Datación RadiométricaRESUMEN
The Middle and Late Bronze Age, a period roughly spanning the 2nd millennium BC (ca. 2000-1200 BC) in the Near East, is frequently referred to as the first 'international age', characterized by intense and far-reaching contacts between different entities from the eastern Mediterranean to the Near East and beyond. In a large-scale tandem study of stable isotopes and ancient DNA of individuals excavated at Tell Atchana (Alalakh, located in Hatay, Turkey), we explored the role of mobility at the capital of a regional kingdom, named Mukish during the Late Bronze Age, which spanned the Amuq Valley and some areas beyond. We generated strontium and oxygen isotope data from dental enamel for 53 individuals and 77 individuals, respectively, and added ancient DNA data of 10 newly sequenced individuals to a dataset of 27 individuals published in 2020. Additionally, we improved the DNA coverage of one individual from this 2020 dataset. The DNA data revealed a very homogeneous gene pool. This picture of an overwhelmingly local ancestry was consistent with the evidence of local upbringing in most of the individuals indicated by the isotopic data, where only five were found to be non-local. High levels of contact, trade, and exchange of ideas and goods in the Middle and Late Bronze Ages, therefore, seem not to have translated into high levels of individual mobility detectable at Tell Atchana.