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1.
Science ; 362(6419)2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30409807

RESUMO

Studies of the peopling of the Americas have focused on the timing and number of initial migrations. Less attention has been paid to the subsequent spread of people within the Americas. We sequenced 15 ancient human genomes spanning from Alaska to Patagonia; six are ≥10,000 years old (up to ~18× coverage). All are most closely related to Native Americans, including those from an Ancient Beringian individual and two morphologically distinct "Paleoamericans." We found evidence of rapid dispersal and early diversification that included previously unknown groups as people moved south. This resulted in multiple independent, geographically uneven migrations, including one that provides clues of a Late Pleistocene Australasian genetic signal, as well as a later Mesoamerican-related expansion. These led to complex and dynamic population histories from North to South America.


Assuntos
Genoma Humano , Migração Humana , Indígenas Norte-Americanos/genética , Conjuntos de Dados como Assunto , Ásia Oriental/etnologia , Genômica , Humanos , América do Norte , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Sibéria/etnologia , América do Sul
2.
Am J Phys Anthropol ; 165(3): 576-588, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29313897

RESUMO

OBJECTIVES: Invertebrate consumption is thought to be an integral part of early hominin diets, and many modern human populations regularly consume insects and other arthropods. This study examines the response of gut microbial community structure and function to changes in diet in wild white-faced capuchins (Cebus capucinus), a primate that incorporates a large proportion of invertebrates in its diet. The goal of the study is to better understand the role of both fruit and invertebrate prey consumption on shaping primate gut microbiomes. MATERIALS AND METHODS: Fecal samples (n = 169) and dietary data were collected over 12 months. The V3-V5 region of microbial 16S rRNA genes was amplified and sequenced. The IM-TORNADO pipeline was used to analyze sequences. RESULTS: White-faced capuchin gut bacterial communities were characterized primarily by Firmicutes (41.6%) and Proteobacteria (39.2%). There was a significant relationship between the invertebrate diet composition of individual capuchins and their gut microbiome composition. However, there was no relationship between the fruit diet composition of individual capuchins and their gut microbiome composition, even when examining multiple timescales. DISCUSSION: The results of our study indicate that there is a stronger relationship between gut microbial community structure and invertebrate diet composition than between gut microbial community structure and fruit consumption. As invertebrates and other animal prey play an important role in the diet of many primates, these results give important insight into the role of faunivory in shaping the evolution of host-microbe interactions in primates.


Assuntos
Cebus/microbiologia , Cebus/fisiologia , Comportamento Alimentar/fisiologia , Microbioma Gastrointestinal/fisiologia , Animais , Antropologia Física , Costa Rica , Fezes/microbiologia , Feminino , Frutas , Insetos , Masculino
3.
PLoS One ; 10(10): e0141808, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26509686

RESUMO

Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748-12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years.


Assuntos
Indígena Americano ou Nativo do Alasca/genética , Genética Populacional , Genoma Mitocondrial , Genômica , Arqueologia , Brasil , Proteínas Correpressoras/genética , DNA Mitocondrial , Evolução Molecular , Genômica/métodos , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Análise de Sequência de DNA
4.
Science ; 344(6185): 750-4, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24833392

RESUMO

Because of differences in craniofacial morphology and dentition between the earliest American skeletons and modern Native Americans, separate origins have been postulated for them, despite genetic evidence to the contrary. We describe a near-complete human skeleton with an intact cranium and preserved DNA found with extinct fauna in a submerged cave on Mexico's Yucatan Peninsula. This skeleton dates to between 13,000 and 12,000 calendar years ago and has Paleoamerican craniofacial characteristics and a Beringian-derived mitochondrial DNA (mtDNA) haplogroup (D1). Thus, the differences between Paleoamericans and Native Americans probably resulted from in situ evolution rather than separate ancestry.


Assuntos
Evolução Biológica , Indígenas Norte-Americanos/genética , Esqueleto , Sequência de Bases , DNA Mitocondrial/genética , Haplótipos , Humanos , México , Dados de Sequência Molecular , Paleontologia , Datação Radiométrica , Crânio/anatomia & histologia
5.
Proc Natl Acad Sci U S A ; 107(15): 6759-64, 2010 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-20351276

RESUMO

The Farming/Language Dispersal Hypothesis posits that prehistoric population expansions, precipitated by the innovation or early adoption of agriculture, played an important role in the uneven distribution of language families recorded across the world. In this case, the most widely spread language families today came to be distributed at the expense of those that have more restricted distributions. In the Americas, Uto-Aztecan is one such language family that may have been spread across Mesoamerica and the American Southwest by ancient farmers. We evaluated this hypothesis with a large-scale study of mitochondrial DNA (mtDNA) and Y-chromosomal DNA variation in indigenous populations from these regions. Partial correlation coefficients, determined with Mantel tests, show that Y-chromosome variation in indigenous populations from the American Southwest and Mesoamerica correlates significantly with linguistic distances (r = 0.33-0.384; P < 0.02), whereas mtDNA diversity correlates significantly with only geographic distance (r = 0.619; P = 0.002). The lack of correlation between mtDNA and Y-chromosome diversity is consistent with differing population histories of males and females in these regions. Although unlikely, if groups of Uto-Aztecan speakers were responsible for the northward spread of agriculture and their languages from Mesoamerica to the Southwest, this migration was possibly biased to males. However, a recent in situ population expansion within the American Southwest (2,105 years before present; 99.5% confidence interval = 1,273-3,773 YBP), one that probably followed the introduction and intensification of maize agriculture in the region, may have blurred ancient mtDNA patterns, which might otherwise have revealed a closer genetic relationship between females in the Southwest and Mesoamerica.


Assuntos
Cromossomos Humanos Y/ultraestrutura , DNA Mitocondrial/ultraestrutura , Variação Genética , Indígenas Norte-Americanos/genética , Idioma , Agricultura/métodos , Evolução Biológica , América Central , Emigração e Imigração , Etnicidade/genética , Feminino , Genética Populacional , História Antiga , Humanos , Indígenas Norte-Americanos/história , Masculino , Dados de Sequência Molecular , Fatores Sexuais , Sudoeste dos Estados Unidos , Zea mays/metabolismo
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