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Yediay, F. E.

Publications and source records attributed to Yediay, F. E..

3 recordsLinked to original sources

Ancient genomics support deep divergence between Eastern and Western Mediterranean Indo-European languages

The Indo-European languages are among the most widely spoken in the world, yet their early diversification remains contentious1-5. It is widely accepted that the spread of this language family across Europe from the 5th millennium BP correlates with the expansion and diversification of steppe-related genetic ancestry from the onset of the Bronze Age6,7. However, multiple steppe-derived populations co-existed in Europe during this period, and it remains unclear how these populations diverged and which provided the demographic channels for the ancestral forms of the Italic, Celtic, Greek, and Armenian languages8,9. To investigate the ancestral histories of Indo-European-speaking groups in Southern Europe, we sequenced genomes from 314 ancient individuals from the Mediterranean and surrounding regions, spanning from 5,200 BP to 2,100 BP, and co-analysed these with published genome data. We additionally conducted strontium isotope analyses on 224 of these individuals. We find a deep east-west divide of steppe ancestry in Southern Europe during the Bronze Age. Specifically, we show that the arrival of steppe ancestry in Spain, France, and Italy was mediated by Bell Beaker (BB) populations of Western Europe, likely contributing to the emergence of the Italic and Celtic languages. In contrast, Armenian and Greek populations acquired steppe ancestry directly from Yamnaya groups of Eastern Europe. These results are consistent with the linguistic Italo-Celtic10,11 and Graeco-Armenian1,12,13 hypotheses accounting for the origins of most Mediterranean Indo-European languages of Classical Antiquity. Our findings thus align with specific linguistic divergence models for the Indo-European language family while contradicting others. This underlines the power of ancient DNA in uncovering prehistoric diversifications of human populations and language communities.

genetics↗

Steppe Ancestry in western Eurasia and the spread of the Germanic Languages

Today, Germanic languages, including German, English, Frisian, Dutch and the Nordic languages, are widely spoken in northwest Europe. However, key aspects of the assumed arrival and diversification of this linguistic group remain contentious1-3. By adding 712 new ancient human genomes we find an archaeologically elusive population entering Sweden from the Baltic region by around 4000 BP. This population became widespread throughout Scandinavia by 3500 BP, matching the contemporaneous distribution of Palaeo-Germanic, the Bronze Age predecessor of Proto-Germanic4-6. These Baltic immigrants thus offer a new potential vector for the first Germanic speakers to arrive in Scandinavia, some 800 years later than traditionally assumed7-12. Following the disintegration of Proto-Germanic13-16, we find by 1650 BP a southward push from Southern Scandinavia into presumed Celtic-speaking areas, including Germany, Poland and the Netherlands. During the Migration Period (1575-1375 BP), we see this ancestry representing West Germanic Anglo-Saxons in Britain, and Langobards in southern Europe. We find a related large-scale northward migration into Denmark and South Sweden corresponding with historically attested Danes and the expansion of Old Norse. These movements have direct implications for multiple linguistic hypotheses. Our findings show the power of combining genomics with historical linguistics and archaeology in creating a unified, integrated model for the emergence, spread and diversification of a linguistic group.

genetics↗

Indigenous peoples in eastern Brazil: insights from 19th century genomes and metagenomes

Although Brazil was inhabited by more than 3,000 Indigenous populations prior to European colonization, todays Indigenous peoples represent less than 1% of Brazils census population. Some of the decimated communities belonged to the so-called "Botocudos" from central-eastern Brazil. These peoples are thought to represent a case of long-standing genetic continuity bearing a strong craniometric resemblance to that of the oldest Indigenous Americans ("Paleoamericans"). Yet, little is known about their origins and genetic relationship to other Native Americans, as only two "Botocudo" genomes have been sequenced so far and those were surprisingly of Polynesian ancestry. To deepen our knowledge on the genomic history of pre-contact Indigenous Americans and the pathogens they were exposed to, we carbon-dated and sequenced 24 ancient Brazilians (including 22 "Botocudos") whose remains were hosted at the National Museum of Rio de Janeiro and recovered prior to the tragic 2018 fire. The resulting genomes depth of coverage ranged from 0.001x to 24x. Their genetic ancestry was found to be Indigenous American without gene flow from external populations such as Europeans, Africans or Polynesians. Unlike Mesoamericans, the "Botocudos" and Amazonians do not seem to have experienced a population expansion once in the Americas. Moreover, remarkably, their genomes exhibit amongst the lowest levels of heterozygosity worldwide and long runs of homozygosity, which could be explained by unique social practices or a very small effective size. Finally, whole genomes of likely ancient pathogens were recovered, including lineages of Human parvovirus B19 that were possibly introduced after the European contact. Significance statementTo better understand the genetic relationship among Indigenous populations in Brazil, we sequenced the genomes of 24 ancient individuals (22 of which labelled as "Botocudos", a term used to describe hunter-gatherer tribes) whose remains were hosted at the Museu Nacional of Rio de Janeiro prior to the tragic fire that consumed it in 2018. Unlike two previously published "Botocudo" genomes, the 22 "Botocudos" from this study have Indigenous American-related ancestry without any Polynesian-related ancestry, and they are similarly related to several Native Brazilian populations. Finally, unlike Eurasian hunter-gatherers, the "Botocudos" exhibit among the lowest heterozygosity and longest runs of homozygosity worldwide - compatible with a very small effective size and suggesting a unique social structure among hunter-gatherers in the Americas.

genomics↗