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1.
Nature ; 590(7845): 229-237, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568824

RESUMO

New finds in the palaeoanthropological and genomic records have changed our view of the origins of modern human ancestry. Here we review our current understanding of how the ancestry of modern humans around the globe can be traced into the deep past, and which ancestors it passes through during our journey back in time. We identify three key phases that are surrounded by major questions, and which will be at the frontiers of future research. The most recent phase comprises the worldwide expansion of modern humans between 40 and 60 thousand years ago (ka) and their last known contacts with archaic groups such as Neanderthals and Denisovans. The second phase is associated with a broadly construed African origin of modern human diversity between 60 and 300 ka. The oldest phase comprises the complex separation of modern human ancestors from archaic human groups from 0.3 to 1 million years ago. We argue that no specific point in time can currently be identified at which modern human ancestry was confined to a limited birthplace, and that patterns of the first appearance of anatomical or behavioural traits that are used to define Homo sapiens are consistent with a range of evolutionary histories.


Assuntos
Migração Humana/história , Linhagem , África/etnologia , Animais , Fósseis , Fluxo Gênico/genética , História Antiga , Humanos , Homem de Neandertal/genética
2.
Nature ; 590(7844): 103-110, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33361817

RESUMO

Humans settled the Caribbean about 6,000 years ago, and ceramic use and intensified agriculture mark a shift from the Archaic to the Ceramic Age at around 2,500 years ago1-3. Here we report genome-wide data from 174 ancient individuals from The Bahamas, Haiti and the Dominican Republic (collectively, Hispaniola), Puerto Rico, Curaçao and Venezuela, which we co-analysed with 89 previously published ancient individuals. Stone-tool-using Caribbean people, who first entered the Caribbean during the Archaic Age, derive from a deeply divergent population that is closest to Central and northern South American individuals; contrary to previous work4, we find no support for ancestry contributed by a population related to North American individuals. Archaic-related lineages were >98% replaced by a genetically homogeneous ceramic-using population related to speakers of languages in the Arawak family from northeast South America; these people moved through the Lesser Antilles and into the Greater Antilles at least 1,700 years ago, introducing ancestry that is still present. Ancient Caribbean people avoided close kin unions despite limited mate pools that reflect small effective population sizes, which we estimate to be a minimum of 500-1,500 and a maximum of 1,530-8,150 individuals on the combined islands of Puerto Rico and Hispaniola in the dozens of generations before the individuals who we analysed lived. Census sizes are unlikely to be more than tenfold larger than effective population sizes, so previous pan-Caribbean estimates of hundreds of thousands of people are too large5,6. Confirming a small and interconnected Ceramic Age population7, we detect 19 pairs of cross-island cousins, close relatives buried around 75 km apart in Hispaniola and low genetic differentiation across islands. Genetic continuity across transitions in pottery styles reveals that cultural changes during the Ceramic Age were not driven by migration of genetically differentiated groups from the mainland, but instead reflected interactions within an interconnected Caribbean world1,8.


Assuntos
Arqueologia , Genética Populacional , Genoma Humano/genética , Migração Humana/história , Ilhas , Dinâmica Populacional/história , Arqueologia/ética , Região do Caribe , América Central/etnologia , Cerâmica/história , Genética Populacional/ética , Mapeamento Geográfico , Haplótipos , História Antiga , Humanos , Masculino , Densidade Demográfica , América do Sul/etnologia
3.
PLoS One ; 15(12): e0229370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326416

RESUMO

The present study applies a dental morphological perspective to the understanding of the complex pre-contact population history of the South Central Andes, through the detection of the underlying dynamics, and the assessment of the biological ties among groups. It presents an analysis of 1591 individuals from 66 sites that date from the Archaic to the Late Intermediate phases from Bolivia, Chile and Peru. The results suggest this area is characterized by significant movement of people and cultures and, at the same time, by long standing population continuity, and highlight the need for wider perspectives capable of taking into account both the different micro-regional realities and the region in its entirety.


Assuntos
Migração Humana/história , Dinâmica Populacional/história , Arqueologia , Bolívia , Chile , Feminino , Fósseis , História Antiga , Humanos , Índios Sul-Americanos , Masculino , Peru , Dente
4.
Am J Hum Genet ; 107(4): 583-588, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007197

RESUMO

Simulation plays a central role in population genomics studies. Recent years have seen rapid improvements in software efficiency that make it possible to simulate large genomic regions for many individuals sampled from large numbers of populations. As the complexity of the demographic models we study grows, however, there is an ever-increasing opportunity to introduce bugs in their implementation. Here, we describe two errors made in defining population genetic models using the msprime coalescent simulator that have found their way into the published record. We discuss how these errors have affected downstream analyses and give recommendations for software developers and users to reduce the risk of such errors.


Assuntos
Genética Populacional/tendências , Genoma Humano , Modelos Genéticos , Software , Algoritmos , Simulação por Computador , Demografia , Variação Genética , Genética Populacional/história , História Antiga , Migração Humana/história , Migração Humana/estatística & dados numéricos , Humanos
5.
Nat Commun ; 11(1): 5347, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093464

RESUMO

In 1970, the seventh pandemic of cholera (7 P) reached both Africa and Europe. Between 1970 and 2011, several European countries reported cholera outbreaks of a few to more than 2,000 cases. We report here a whole-genome analysis of 1,324 7 P V. cholerae El Tor (7 PET) isolates, including 172 from autochthonous sporadic or outbreak cholera cases occurring between 1970 and 2011 in Europe, providing insight into the spatial and temporal spread of this pathogen across Europe. In this work, we show that the 7 PET lineage was introduced at least eight times into two main regions: Eastern and Southern Europe. Greater recurrence of the disease was observed in Eastern Europe, where it persisted until 2011. It was introduced into this region from Southern Asia, often circulating regionally in the countries bordering the Black Sea, and in the Middle East before reaching Eastern Africa on several occasions. In Southern Europe, the disease was mostly seen in individual countries during the 1970s and was imported from North and West Africa, except in 1994, when cholera was imported into Albania and Italy from the Black Sea region. These results shed light on the geographic course of cholera during the seventh pandemic and highlight the role of humans in its global dissemination.


Assuntos
Cólera/história , Pandemias/história , Cólera/epidemiologia , Cólera/microbiologia , Farmacorresistência Bacteriana/genética , Europa (Continente)/epidemiologia , Evolução Molecular , Genoma Bacteriano , Genômica , História do Século XX , História do Século XXI , Migração Humana/história , Humanos , Filogenia , Ribotipagem , Análise Espaço-Temporal , Vibrio cholerae/classificação , Vibrio cholerae/genética , Vibrio cholerae/isolamento & purificação
6.
Nature ; 585(7825): 390-396, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939067

RESUMO

The maritime expansion of Scandinavian populations during the Viking Age (about AD 750-1050) was a far-flung transformation in world history1,2. Here we sequenced the genomes of 442 humans from archaeological sites across Europe and Greenland (to a median depth of about 1×) to understand the global influence of this expansion. We find the Viking period involved gene flow into Scandinavia from the south and east. We observe genetic structure within Scandinavia, with diversity hotspots in the south and restricted gene flow within Scandinavia. We find evidence for a major influx of Danish ancestry into England; a Swedish influx into the Baltic; and Norwegian influx into Ireland, Iceland and Greenland. Additionally, we see substantial ancestry from elsewhere in Europe entering Scandinavia during the Viking Age. Our ancient DNA analysis also revealed that a Viking expedition included close family members. By comparing with modern populations, we find that pigmentation-associated loci have undergone strong population differentiation during the past millennium, and trace positively selected loci-including the lactase-persistence allele of LCT and alleles of ANKA that are associated with the immune response-in detail. We conclude that the Viking diaspora was characterized by substantial transregional engagement: distinct populations influenced the genomic makeup of different regions of Europe, and Scandinavia experienced increased contact with the rest of the continent.


Assuntos
Fluxo Gênico/genética , Genética Populacional , Genoma Humano/genética , Genômica , Migração Humana/história , Alelos , Conjuntos de Dados como Assunto , Inglaterra , Evolução Molecular , Groenlândia , História Medieval , Humanos , Imunidade/genética , Irlanda , Lactase/genética , Lactase/metabolismo , Masculino , Países Escandinavos e Nórdicos , Seleção Genética , Análise Espaço-Temporal , Adulto Jovem
8.
Nature ; 583(7817): 572-577, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641827

RESUMO

The possibility of voyaging contact between prehistoric Polynesian and Native American populations has long intrigued researchers. Proponents have pointed to the existence of New World crops, such as the sweet potato and bottle gourd, in the Polynesian archaeological record, but nowhere else outside the pre-Columbian Americas1-6, while critics have argued that these botanical dispersals need not have been human mediated7. The Norwegian explorer Thor Heyerdahl controversially suggested that prehistoric South American populations had an important role in the settlement of east Polynesia and particularly of Easter Island (Rapa Nui)2. Several limited molecular genetic studies have reached opposing conclusions, and the possibility continues to be as hotly contested today as it was when first suggested8-12. Here we analyse genome-wide variation in individuals from islands across Polynesia for signs of Native American admixture, analysing 807 individuals from 17 island populations and 15 Pacific coast Native American groups. We find conclusive evidence for prehistoric contact of Polynesian individuals with Native American individuals (around AD 1200) contemporaneous with the settlement of remote Oceania13-15. Our analyses suggest strongly that a single contact event occurred in eastern Polynesia, before the settlement of Rapa Nui, between Polynesian individuals and a Native American group most closely related to the indigenous inhabitants of present-day Colombia.


Assuntos
Fluxo Gênico/genética , Genoma Humano/genética , Migração Humana/história , Índios Centro-Americanos/genética , Índios Sul-Americanos/genética , Ilhas , Grupo com Ancestrais Oceânicos/genética , América Central/etnologia , Colômbia/etnologia , Europa (Continente)/etnologia , Genética Populacional , História Medieval , Humanos , Polimorfismo de Nucleotídeo Único/genética , Polinésia , América do Sul/etnologia , Fatores de Tempo
10.
Nature ; 584(7819): 87-92, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32699412

RESUMO

The initial colonization of the Americas remains a highly debated topic1, and the exact timing of the first arrivals is unknown. The earliest archaeological record of Mexico-which holds a key geographical position in the Americas-is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the first American populations2. However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico3,4, the Chiapas Highlands5, Central Mexico6 and the Caribbean coast7-9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave-a high-altitude site in central-northern Mexico-that corroborate previous findings in the Americas10-17of cultural evidence that dates to the Last Glacial Maximum (26,500-19,000 years ago)18, and which push back dates for human dispersal to the region possibly as early as 33,000-31,000 years ago. The site yielded about 1,900 stone artefacts within a 3-m-deep stratified sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50 radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research.


Assuntos
Migração Humana/história , Camada de Gelo , Altitude , Arqueologia , Teorema de Bayes , Cavernas , Diversidade Cultural , DNA Antigo/análise , História Antiga , Humanos , México
11.
Nature ; 584(7819): 93-97, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32699413

RESUMO

The peopling of the Americas marks a major expansion of humans across the planet. However, questions regarding the timing and mechanisms of this dispersal remain, and the previously accepted model (termed 'Clovis-first')-suggesting that the first inhabitants of the Americas were linked with the Clovis tradition, a complex marked by distinctive fluted lithic points1-has been effectively refuted. Here we analyse chronometric data from 42 North American and Beringian archaeological sites using a Bayesian age modelling approach, and use the resulting chronological framework to elucidate spatiotemporal patterns of human dispersal. We then integrate these patterns with the available genetic and climatic evidence. The data obtained show that humans were probably present before, during and immediately after the Last Glacial Maximum (about 26.5-19 thousand years ago)2,3 but that more widespread occupation began during a period of abrupt warming, Greenland Interstadial 1 (about 14.7-12.9 thousand years before AD 2000)4. We also identify the near-synchronous commencement of Beringian, Clovis and Western Stemmed cultural traditions, and an overlap of each with the last dates for the appearance of 18 now-extinct faunal genera. Our analysis suggests that the widespread expansion of humans through North America was a key factor in the extinction of large terrestrial mammals.


Assuntos
Extinção Biológica , Migração Humana/história , Mamíferos , Animais , Arqueologia , Teorema de Bayes , Mapeamento Geográfico , História Antiga , Humanos , Mamíferos/classificação , América do Norte , Fatores de Tempo
12.
PLoS One ; 15(4): e0232455, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353046

RESUMO

This article explores the changes that occurred in harvesting technology during the dispersal of the Neolithic in the Mediterranean basin. It does so through technological and use-wear analysis of flaked stone tools from archaeological sites dated between ca. 7000 and 5000 cal BCE, from the Aegean Sea to the westernmost coasts of Portugal. The main goal is to analyse the transformations that occurred in the harvesting toolkit. Our study reveals dynamics of continuity and change in sickles at a Mediterranean scale, resulting from adaptations of the migrant groups to the newly occupied territories and from processes of technological innovation. Adaptations in the production system of the inserts and in their use-pattern occurred in relation to lithic raw material availability and knappers' skills, but also in relation to the scale of production and farming techniques. A major shift took place in the north-western Mediterranean arc with the diffusion of parallel-hafted inserts, probably as a result of heterogeneous phenomena including the diffusion of new groups, technical transfers, establishment of new interaction networks and new systems of lithic production.


Assuntos
Agricultura/instrumentação , Migração Humana/história , Tecnologia/história , Agricultura/história , Arqueologia , História Antiga , Humanos , Ilhas do Mediterrâneo
13.
Nature ; 581(7808): 299-302, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433609

RESUMO

The Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin1. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H. sapiens. Here we report the discovery and direct dating of human remains found in association with Initial Upper Palaeolithic artefacts2, from excavations at Bacho Kiro Cave (Bulgaria). Morphological analysis of a tooth and mitochondrial DNA from several hominin bone fragments, identified through proteomic screening, assign these finds to H. sapiens and link the expansion of Initial Upper Palaeolithic technologies with the spread of H. sapiens into the mid-latitudes of Eurasia before 45 thousand years ago3. The excavations yielded a wealth of bone artefacts, including pendants manufactured from cave bear teeth that are reminiscent of those later produced by the last Neanderthals of western Europe4-6. These finds are consistent with models based on the arrival of multiple waves of H. sapiens into Europe coming into contact with declining Neanderthal populations7,8.


Assuntos
Fósseis , Migração Humana/história , Animais , Ásia , Osso e Ossos/metabolismo , Bulgária , Cavernas , DNA Antigo/isolamento & purificação , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Europa (Continente) , História Antiga , Humanos , Homem de Neandertal/genética , Filogenia , Comportamento de Utilização de Ferramentas , Dente/anatomia & histologia , Dente/metabolismo
14.
PLoS One ; 15(5): e0233184, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428013

RESUMO

Ancient DNA studies have shown that early farming spread through most of Europe by the range expansion of farmers of Anatolian origin rather than by the conversion to farming of the local hunter-gatherers, and have confirmed that these hunter-gatherers continued to coexist with the incoming farmers. In this short report, I extend a previous three-population wave-of-advance model to accommodate these new findings, and derive the conditions supportive of such a scenario in terms of the relative magnitudes of the parameters. The revised model predicts that the conversion rate must, not surprisingly, be low, but also that the hunter-gatherers must compete more strongly with the converted farmers than with the alien farmers. Moreover, competition with the hunter-gatherers diminishes the speed of the wave-of advance of the farmers. In addition, I briefly consider how the wave-of-advance approach may contribute to interpreting the results of archaeological studies using the summed probability distribution of radiocarbon dates.


Assuntos
Agricultura/história , DNA Antigo , Migração Humana/história , Modelos Biológicos , História Antiga , Humanos
15.
Am J Hum Genet ; 107(1): 149-157, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32470374

RESUMO

The Iron and Classical Ages in the Near East were marked by population expansions carrying cultural transformations that shaped human history, but the genetic impact of these events on the people who lived through them is little-known. Here, we sequenced the whole genomes of 19 individuals who each lived during one of four time periods between 800 BCE and 200 CE in Beirut on the Eastern Mediterranean coast at the center of the ancient world's great civilizations. We combined these data with published data to traverse eight archaeological periods and observed any genetic changes as they arose. During the Iron Age (∼1000 BCE), people with Anatolian and South-East European ancestry admixed with people in the Near East. The region was then conquered by the Persians (539 BCE), who facilitated movement exemplified in Beirut by an ancient family with Egyptian-Lebanese admixed members. But the genetic impact at a population level does not appear until the time of Alexander the Great (beginning 330 BCE), when a fusion of Asian and Near Easterner ancestry can be seen, paralleling the cultural fusion that appears in the archaeological records from this period. The Romans then conquered the region (31 BCE) but had little genetic impact over their 600 years of rule. Finally, during the Ottoman rule (beginning 1516 CE), Caucasus-related ancestry penetrated the Near East. Thus, in the past 4,000 years, three limited admixture events detectably impacted the population, complementing the historical records of this culturally complex region dominated by the elite with genetic insights from the general population.


Assuntos
DNA/genética , Genética Populacional/história , Egito , Grupos Étnicos/genética , Grupos Étnicos/história , Genoma Humano/genética , Haplótipos/genética , História Antiga , Migração Humana/história , Humanos , Oriente Médio
16.
PLoS One ; 15(4): e0232367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32339209

RESUMO

Human expansions motivated by the spread of farming are one of the most important processes that shaped cultural geographies during the Holocene. The best known example of this phenomenon is the Neolithic expansion in Europe, but parallels in other parts of the globe have recently come into focus. Here, we examine the expansion of four archaeological cultures of widespread distribution in lowland South America, most of which originated in or around the Amazon basin and spread during the late Holocene with the practice of tropical forest agriculture. We analyze spatial gradients in radiocarbon dates of each culture through space-time regressions, allowing us to establish the most likely geographical origin, time and speed of expansion. To further assess the feasibility of demic diffusion as the process behind the archaeological expansions in question, we employ agent-based simulations with demographic parameters derived from the ethnography of tropical forest farmers. We find that, while some expansions can be realistically modeled as demographic processes, others are not easily explainable in the same manner, which is possibly due to different processes driving their dispersal (e.g. cultural diffusion) or problematic/incomplete archaeological data.


Assuntos
Evolução Cultural/história , Migração Humana/história , Modelos Teóricos , Análise Espaço-Temporal , Agricultura , Arqueologia , Simulação por Computador , História Antiga , Humanos , Idioma , América do Sul
17.
Proc Natl Acad Sci U S A ; 117(18): 9793-9799, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32284419

RESUMO

The development of pastoralism transformed human diets and societies in grasslands worldwide. The long-term success of cattle herding in Africa has been sustained by dynamic food systems, consumption of a broad range of primary and secondary livestock products, and the evolution of lactase persistence (LP), which allows digestion of lactose into adulthood and enables the milk-based, high-protein, low-calorie diets characteristic of contemporary pastoralists. Despite the presence of multiple alleles associated with LP in ancient and present-day eastern African populations, the contexts for selection for LP and the long-term development of pastoralist foodways in this region remain unclear. Pastoral Neolithic (c 5000 to 1200 BP) faunas indicate that herders relied on cattle, sheep, and goats and some hunting, but direct information on milk consumption, plant use, and broader culinary patterns is rare. Combined chemical and isotopic analysis of ceramic sherds (n = 125) from Pastoral Neolithic archaeological contexts in Kenya and Tanzania, using compound-specific δ13C and Δ13C values of the major fatty acids, provides chemical evidence for milk, meat, and plant processing by ancient herding societies in eastern Africa. These data provide the earliest direct evidence for milk product consumption and reveal a history of reliance on animal products and other nutrients, likely extracted through soups or stews, and plant foods. They document a 5,000-y temporal framework for eastern Africa pastoralist cuisines and cultural contexts for selection for alleles distinctive of LP in eastern Africa.


Assuntos
Arqueologia , Dieta , Análise de Alimentos/história , Leite/química , Animais , Isótopos de Carbono/química , Bovinos , Cerâmica/história , Dieta/história , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Cabras , História Antiga , Migração Humana/história , Humanos , Lactase/química , Lactose/química , Gado , Carne/análise , Ovinos
18.
Proc Natl Acad Sci U S A ; 117(16): 8989-9000, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32238559

RESUMO

The European continent was subject to two major migrations of peoples during the Holocene: the northwestward movement of Anatolian farmer populations during the Neolithic and the westward movement of Yamnaya steppe peoples during the Bronze Age. These movements changed the genetic composition of the continent's inhabitants. The Holocene was also characterized by major changes in vegetation composition, which altered the environment occupied by the original hunter-gatherer populations. We aim to test to what extent vegetation change through time is associated with changes in population composition as a consequence of these migrations, or with changes in climate. Using ancient DNA in combination with geostatistical techniques, we produce detailed maps of ancient population movements, which allow us to visualize how these migrations unfolded through time and space. We find that the spread of Neolithic farmer ancestry had a two-pronged wavefront, in agreement with similar findings on the cultural spread of farming from radiocarbon-dated archaeological sites. This movement, however, did not have a strong association with changes in the vegetational landscape. In contrast, the Yamnaya migration speed was at least twice as fast and coincided with a reduction in the amount of broad-leaf forest and an increase in the amount of pasture and natural grasslands in the continent. We demonstrate the utility of integrating ancient genomes with archaeometric datasets in a spatiotemporal statistical framework, which we foresee will enable future studies of ancient populations' movements, and their putative effects on local fauna and flora.


Assuntos
Arqueologia/métodos , Genoma Humano , Migração Humana/história , Modelos Genéticos , Análise Espaço-Temporal , Agricultura/história , Distribuição Animal , DNA Antigo/análise , Conjuntos de Dados como Assunto , Europa (Continente) , Fazendeiros , Estudos de Viabilidade , Florestas , Geografia , Pradaria , História Antiga , Humanos , Dispersão Vegetal , Datação Radiométrica
19.
Proc Natl Acad Sci U S A ; 117(16): 8813-8819, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32253300

RESUMO

The timing of human colonization of East Polynesia, a vast area lying between Hawai'i, Rapa Nui, and New Zealand, is much debated and the underlying causes of this great migration have been enigmatic. Our study generates evidence for human dispersal into eastern Polynesia from islands to the west from around AD 900 and contemporaneous paleoclimate data from the likely source region. Lake cores from Atiu, Southern Cook Islands (SCIs) register evidence of pig and/or human occupation on a virgin landscape at this time, followed by changes in lake carbon around AD 1000 and significant anthropogenic disturbance from c. AD 1100. The broader paleoclimate context of these early voyages of exploration are derived from the Atiu lake core and complemented by additional lake cores from Samoa (directly west) and Vanuatu (southwest) and published hydroclimate proxies from the Society Islands (northeast) and Kiribati (north). Algal lipid and leaf wax biomarkers allow for comparisons of changing hydroclimate conditions across the region before, during, and after human arrival in the SCIs. The evidence indicates a prolonged drought in the likely western source region for these colonists, lasting c. 200 to 400 y, contemporaneous with the phasing of human dispersal into the Pacific. We propose that drying climate, coupled with documented social pressures and societal developments, instigated initial eastward exploration, resulting in SCI landfall(s) and return voyaging, with colonization a century or two later. This incremental settlement process likely involved the accumulation of critical maritime knowledge over several generations.


Assuntos
Arqueologia/métodos , Secas , Sedimentos Geológicos/análise , Migração Humana/história , História Antiga , Humanos , Lagos , Polinésia
20.
PLoS One ; 15(4): e0230303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240202

RESUMO

The current paper presents three studies, which suggest that perceiving one's nation as transgenerational (TG) is related to a differentiation in the evaluation of ethnically German diaspora migrants and ethnically non-German ('foreign') migrants. First, we find that unlike 'classical' concepts such as right-wing authoritarianism (RWA), social dominance orientation (SDO), and hierarchic self-interest (HSI), TG explains differences in derogatory sentiments expressed towards diaspora and 'foreign' migrants. Second, TG is differentially related to positive emotions and behavioral intentions expressed towards these two groups of migrants. Lastly, results indicate that people who perceive the ingroup as TG require 'foreign' migrants to fulfill more criteria that make them eligible for citizenship and are thereby more exclusionist than people who include only the current generation into their concept of national identity. The social implications of these findings in face of the so-called refugee crisis in Germany and the wider European Union are discussed.


Assuntos
Autoritarismo , Grupos Étnicos/psicologia , Relação entre Gerações/etnologia , Percepção Social , Migrantes/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/etnologia , História do Século XIX , História do Século XX , História do Século XXI , Migração Humana/história , Humanos , Internacionalidade/história , Israel/etnologia , Masculino , Pessoa de Meia-Idade
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