Rethinking the dispersal of Homo sapiens out of Africa

Groucutt et al.

Abstract:

Current fossil, genetic, and archeological data indicate that Homo sapiens originated in Africa in the

late Middle Pleistocene. By the end of the Late Pleistocene, our species was distributed across every continent except Antarctica, setting the foundations for the subsequent demographic and cultural changes of the Holocene. The intervening processes remain intensely debated and a key theme in hominin evolutionary studies. We review archeological, fossil, environmental, and genetic data to evaluate the current state of knowledge on the dispersal of Homo sapiens out of Africa. The emerging picture of the dispersal process suggests dynamic behavioral variability, complex interactions between populations, and an intricate genetic and cultural legacy. This evolutionary and historical complexity challenges simple narratives and suggests that hybrid models and the testing of explicit hypotheses are required to understand the expansion of Homo sapiens into Eurasia.


Link to study 1 & link 2

Genomic study of the Ket: a Paleo-Eskimo-related ethnic group with significant ancient North Eurasian ancestry

Flegontov et al.

Abstract:

The Kets, an ethnic group in the Yenisei River basin, Russia, are considered the last nomadic
hunter-gatherers of Siberia, and Ket language has no transparent affiliation with any language
family. We investigated connections between the Kets and Siberian and North American populations, with emphasis on the Mal'ta and Paleo-Eskimo ancient genomes, using original data from 46 unrelated samples of Kets and 42 samples of their neighboring ethnic groups (Uralicspeaking
Nganasans, Enets, and Selkups). We genotyped over 130,000 autosomal SNPs, determined mitochondrial and Y-chromosomal haplogroups, and performed high-coverage genome sequencing of two Ket individuals. We established that the Kets belong to the cluster of Siberian populations related to Paleo-Eskimos. Unlike other members of this cluster (Nganasans, Ulchi, Yukaghirs, and Evens), Kets and closely related Selkups have a high degree of Mal'ta ancestry. Implications of these findings for the linguistic hypothesis uniting Ket and Na-Dene languages into a language macrofamily are discussed. 


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Testing modern human out-of-Africa dispersal models and implications for modern human origins

Reyes-Centeno et al.


Abstract:

The modern human expansion process out of Africa has important implications for understanding the genetic and phenotypic structure of extant populations. While intensely debated, the primary hypotheses focus on either a single dispersal or multiple dispersals out of the continent. Here, we use the human fossil record from Africa and the Levant, as well as an exceptionally large dataset of Holocene human crania sampled from Asia, to model ancestor–descendant relationships along hypothetical dispersal routes. We test the spatial and temporal predictions of competing out-of-Africa models by assessing the correlation of geographical distances between populations and measures of population differentiation derived from quantitative cranial phenotype data. Our results support a model in which extant Australo-Melanesians are descendants of an initial dispersal out of Africa by early anatomically modern humans, while all other populations are descendants of a later migration wave. Our results have implications for understanding the complexity of modern human origins and diversity.


Link to study


Notes:

There are arguments against this model and the current genetic evidence doesn't really support this but as David says things over at Eurogenes; if this is confirmed via ancient DNA results then the old idea of "Eastern Non-Africans/East Eurasians" may just collapse  and things will look a whole lot more complex. But this seems to be more based on skull morphology? So its reliability is honestly pretty damn low in my humble opinion. 

Strata on loanwords from Arabic and other Semitic languages in Northern Somali

By Giorgio Banti

Excerpt:

An Ancient South Arabian (ASA) loanword in NS was identified by Cerulli (1959: 119), i.e., NS addôon m. ‘slave’. But a systematic study of the contacts between ASA, Himyaritic, and NS has not been done yet. Nevertheless, a few possible ASA (or Himyaritic) loanwords can be identified in NS.

 NS addôon m. and addóon f. ‘slave’ (pl. addoomó m.) has -n < -m in syllable coda, a regular development in NS (cf. § 1.) Cerulli (1959: 119) connected it with Sabaic ’dm ‘servants, vassals, religious servants’. This particular semantic development of the well-known Semitic root ’DM still survives in Modern Yemeni Ar. ’awādim ‘domestics’ (Ricks 1989: 5). Notice that -oo- is here probably from *-a- or *-ā-, a development that took place in the donor language, not in NS. Modern South Arabian (MSA) languages have several instances of accented *-āɹ- > -ōɹ- (> -ūɹ-).

NS gêel m. ‘camel’ has -ee- < -aa-, that is still preserved, e.g., in NS compounds like haruub-gâal m. ‘vessel for milking camels’ or daba-ggáalle m. ‘ground squirrel’ (lit. ‘having a camel tail’), etc. East Cushitic *gaala ‘camel’ is from Semitic *gamal- ‘id.’ and the most likely intermediary has been a language spoken in Southern Arabia when camels were introduced to the eastern Horn ca. 2000 years ago, as argued in Banti (2000: 49 f.). Gml ‘camel’ is well attested in Sabaic. However, the loss of -m- is not regular in ASA, nor in NS or any known East Cushitic language, and points to a different language: loss of -m- between vowels occurs several times in Southern Ethiosemitic and in MSA.

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When the Waves of European Neolithization Met: First Paleogenetic Evidence from Early Farmers in the Southern Paris Basin

Rivollat et al.

Abstract:

An intense debate concerning the nature and mode of Neolithic transition in Europe has long received much attention. Recent publications of paleogenetic analyses focusing on ancient European farmers from Central Europe or the Iberian Peninsula have greatly contributed to this debate, providing arguments in favor of major migrations accompanying European Neolithization and highlighting noticeable genetic differentiation between farmers associated with two archaeologically defined migration routes: the Danube valley and the Mediterranean Sea. The aim of the present study was to fill a gap with the first paleogenetic data of Neolithic settlers from a region (France) where the two great currents came into both direct and indirect contact with each other. To this end, we analyzed the Gurgy 'Les Noisats' group, an Early/Middle Neolithic necropolis in the southern part of the Paris Basin. Interestingly, the archaeological record from this region highlighted a clear cultural influence from the Danubian cultural sphere but also notes exchanges with the Mediterranean cultural area. To unravel the processes implied in these cultural exchanges, we analyzed 102 individuals and obtained the largest Neolithic mitochondrial gene pool so far (39 HVS-I mitochondrial sequences and haplogroups for 55 individuals) from a single archaeological site from the Early/Middle Neolithic period. Pairwise FST values, haplogroup frequencies and shared informative haplotypes were calculated and compared with ancient and modern European and Near Eastern populations. These descriptive analyses provided patterns resulting from different evolutionary scenarios; however, the archaeological data available for the region suggest that the Gurgy group was formed through equivalent genetic contributions of farmer descendants from the Danubian and Mediterranean Neolithization waves. However, these results, that would constitute the most ancient genetic evidence of admixture between farmers from both Central and Mediterranean migration routes in the European Neolithization debate, are subject to confirmation through appropriate model-based approaches.


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Genomic evidence for the Pleistocene and recent population history of Native Americans

Raghavan et al.

Abstract:

How and when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we find that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (KYA), and after no more than 8,000-year isolation period in Beringia. Following their arrival to the Americas, ancestral Native Americans diversified into two basal genetic branches around 13 KYA, one that is now dispersed across North and South America and the other is restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians (including Siberians) and, more distantly, Australo-Melanesians. Putative ‘Paleoamerican’ relict populations, including the historical Mexican Pericúes and South American Fuego-Patagonians, are not directly related to modern Australo-Melanesians as suggested by the Paleoamerican Model.


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Genetic evidence for two founding populations of the Americas

Skoglund et al.

Abstract:

Genetic studies have consistently indicated a single common origin of Native American groups from Central and South America. However, some morphological studies have suggested a more complex picture, whereby the northeast Asian affinities of present-day Native Americans contrast with a distinctive morphology seen in some of the earliest American skeletons, which share traits with present-day Australasians (indigenous groups in Australia, Melanesia, and island Southeast Asia). Here we analyse genome-wide data to show that some Amazonian Native Americans descend partly from a Native American founding population that carried ancestry more closely related to indigenous Australians, New Guineans and Andaman Islanders than to any present-day Eurasians or Native Americans. This signature is not present to the same extent, or at all, in present-day Northern and Central Americans or in a ~12,600-year-old Clovis-associated genome, suggesting a more diverse set of founding populations of the Americas than previously accepted.

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