August 29, 2016

Gobero (Green Sahara key site) documentary

This site of Gobero (Niger) was news in the archaeology and anthropology circles a few years ago and today I stumbled on this quite nice video documentary on it that I believe will be of interest for many readers:


August 21, 2016

Paleolithic European mtDNA lineage U5b2c1 in Carthaginian man

Quickies

Elizabeth A. Matisoo-Smith et al. A European Mitochondrial Haplotype Identified in Ancient Phoenician Remains from Carthage, North Africa. PLoS ONE 2016. Open accessLINK [doi:10.1371/journal.pone.0155046]

Abstract

While Phoenician culture and trade networks had a significant impact on Western civilizations, we know little about the Phoenicians themselves. In 1994, a Punic burial crypt was discovered on Byrsa Hill, near the entry to the National Museum of Carthage in Tunisia. Inside this crypt were the remains of a young man along with a range of burial goods, all dating to the late 6th century BCE. Here we describe the complete mitochondrial genome recovered from the Young Man of Byrsa and identify that he carried a rare European haplogroup, likely linking his maternal ancestry to Phoenician influenced locations somewhere on the North Mediterranean coast, the islands of the Mediterranean or the Iberian Peninsula. This result not only provides the first direct ancient DNA evidence of a Phoenician individual but the earliest evidence of a European mitochondrial haplogroup, U5b2c1, in North Africa.

The lineage is the same one as La Braña 1, an Epipaleolithic man buried in a cave at the mountains NE of León. Its presence on a Carthaginian from the 6th century BCE almost certainly indicates that he had native Iberian maternal ancestry, that his family had arrived to Carthage from Gadir (modern Cádiz) or some of the other Phoenician colonies of Andalusia. The location of his burial at the acropolis and the wealth of the burial goods indicate that he belonged to the highest social elite of the still incipient Carthaginian empire. He has been nicknamed "Ariche" (the loved one) and his face reconstructed as you can see in this blog.

Thanks to Jamel of Lapurdi for the reference an a nice related discussion.

All the Neolithic and Chalcolithic of Ireland in a single paper


This entry should be a "quickie" because I wouldn't even know where to begin in order to analyze this comprehensive synthesis and not at all because it is a lesser study, all the oposite. Just to say that the average reader of this blog will want to read it, much more if they are Irish.

However I think that the paper raises some interesting questions regarding the chronology of "modern genetic Irishness" and the arrival of the Y-DNA lineage R1b to the island, which I cast below for your insights.


T. Rowan McLaughling et al., The Changing Face of Neolithic and Bronze Age Ireland: A Big Data Approach to the Settlement and Burial Records. Journal of World Prehistory 2016. Open accessLINK [doi:10.1007/s10963-016-9093-0]

Abstract

This paper synthesizes and discusses the spatial and temporal patterns of archaeological sites in Ireland, spanning the Neolithic period and the Bronze Age transition (4300–1900 cal BC), in order to explore the timing and implications of the main changes that occurred in the archaeological record of that period. Large amounts of new data are sourced from unpublished developer-led excavations and combined with national archives, published excavations and online databases. Bayesian radiocarbon models and context- and sample-sensitive summed radiocarbon probabilities are used to examine the dataset. The study captures the scale and timing of the initial expansion of Early Neolithic settlement and the ensuing attenuation of all such activity—an apparent boom-and-bust cycle. The Late Neolithic and Chalcolithic periods are characterised by a resurgence and diversification of activity. Contextualisation and spatial analysis of radiocarbon data reveals finer-scale patterning than is usually possible with summed-probability approaches: the boom-and-bust models of prehistoric populations may, in fact, be a misinterpretation of more subtle demographic changes occurring at the same time as cultural change and attendant differences in the archaeological record.

The study should be very useful to anyone trying to understand the prehistory of Ireland, not the least because of its many maps and this extremely cool sequential maps video from pre-Neolithic times (5th millennium BCE) to the gates of the Bronze Age (early 2nd millennium BCE). Notice that in the Isles they tend to call "Bronze Age" to the Chalcolithic (Copper and Stone Age) and hence the title, which is a bit misleading.


An example of the very cool and highly informative maps and data you'll find in this study:
Fig. 3 - Map of Ireland showing Early Neolithic sites

 

Depopulation and resettlement? When?


An intriguing issue is the boom and bust cycles, particularly the almost total absence of signs of human activity around the end of the 4th millennium (3300-3000), suggesting maybe a depopulation after the first farmer colonization (?). There are clear booms around 4000, 3700, 3500, 2900, 2500 and since 2200 (Bell Beaker era). All this is something to chew about.

Particularly I'd raise the following question here: we know that a woman from c. 3400-3100 BCE (just at the depopulation gap?) was a typical Neolithic European, most similar to SE Spaniards and Sardinians, and that a man from c. 2200-1500 (Bell Beaker boom) was virtually identical to modern Irish and "British Celts" like Scots, Welsh and Cornish, carrying the common and controversial R1b patrilineage. 

The initial reading many of us made was that these new genetics may have arrived with Bell Beaker and that maybe Bell Beaker was more influential in terms demographic than we used to think, at least in Ireland. However, with this archaeological sequence on hand it seems at least reasonable to think that the major resettlement of an almost deserted Ireland happened after 3000 BCE but significantly earlier than the Bell Beaker phenomenon, which only reaches Northern Europe (Ireland included) c. 1500 BCE. What's your opinion?

Genetic prehistory of European bovine cattle

Quickies

Another study on European cattle, suggesting little to no admixture with aboriginal aurochs. However, as far as I can see, they did not directly compare with European aurochsen, so I'm rather skeptic, as their conclusions seem to derive only from modeling out of an incomplete dataset.

Amelie Scheu et al., The genetic prehistory of domesticated cattle from their origin to the spread across Europe. BMC Genetics 2016. Open accessLINK [doi:10.1186/s12863-015-0203-2]

Abstract

Background

Cattle domestication started in the 9th millennium BC in Southwest Asia. Domesticated cattle were then introduced into Europe during the Neolithic transition. However, the scarcity of palaeogenetic data from the first European domesticated cattle still inhibits the accurate reconstruction of their early demography. In this study, mitochondrial DNA from 193 ancient and 597 modern domesticated cattle (Bos taurus) from sites across Europe, Western Anatolia and Iran were analysed to provide insight into the Neolithic dispersal process and the role of the local European aurochs population during cattle domestication.

Results

Using descriptive summary statistics and serial coalescent simulations paired with approximate Bayesian computation we find: (i) decreasing genetic diversity in a southeast to northwest direction, (ii) strong correlation of genetic and geographical distances, iii) an estimated effective size of the Near Eastern female founder population of 81, iv) that the expansion of cattle from the Near East and Anatolia into Europe does not appear to constitute a significant bottleneck, and that v) there is evidence for gene-flow between the Near Eastern/Anatolian and European cattle populations in the early phases of the European Neolithic, but that it is restricted after 5,000 BCE.

Conclusions

The most plausible scenario to explain these results is a single and regionally restricted domestication process of cattle in the Near East with subsequent migration into Europe during the Neolithic transition without significant maternal interbreeding with the endogenous wild stock. Evidence for gene-flow between cattle populations from Southwestern Asia and Europe during the earlier phases of the European Neolithic points towards intercontinental trade connections between Neolithic farmers.




Figure 1

MDS Plot of d-loop sequences from 13 spatiotemporal groups of ancient domesticated cattle. The MDS plot is based on Reynolds’ FST. Numbers represent the age of samples in BCE per group; brackets contain the number of sequences per group.

Mitochondrial DNA of ancient Tocharians

Quickies

It seems there is still something to learn about the ancient Tocharian mummies of Uyghuristan:

Chunxiang Li et al., Analysis of ancient human mitochondrial DNA from the Xiaohe cemetery: insights into prehistoric population movements in the Tarim Basin, China. BMC Genetics 2016. Open accessLINK [doi:10.1186/s12863-015-0237-5]

Abstract

Background

The Tarim Basin in western China, known for its amazingly well-preserved mummies, has been for thousands of years an important crossroad between the eastern and western parts of Eurasia. Despite its key position in communications and migration, and highly diverse peoples, languages and cultures, its prehistory is poorly understood. To shed light on the origin of the populations of the Tarim Basin, we analysed mitochondrial DNA polymorphisms in human skeletal remains excavated from the Xiaohe cemetery, used by the local community between 4000 and 3500 years before present, and possibly representing some of the earliest settlers.

Results

Xiaohe people carried a wide variety of maternal lineages, including West Eurasian lineages H, K, U5, U7, U2e, T, R*, East Eurasian lineages B, C4, C5, D, G2a and Indian lineage M5.

Conclusion

Our results indicate that the people of the Tarim Basin had a diverse maternal ancestry, with origins in Europe, central/eastern Siberia and southern/western Asia. These findings, together with information on the cultural context of the Xiaohe cemetery, can be used to test contrasting hypotheses of route of settlement into the Tarim Basin.


African admixture events

Quickies

This paper is probably of interest to many but I don't have the insight to make a proper analysis. Just to mention that I feel deeply uncomfortable with the use of the "Sub-Saharan" term, which has so many wrong ideas attached to it, particularly the word "sub" (under, below) that it really irks me. Why not Trans-Saharan or Ultra-Saharan?, very Roman and not the least Eurocentric but definitely not just all kinds of wrong, as "Sub" is. Why not Tropical and Southern Africa?

Sub-Saharan is not just implicitly Eurocentric and almost certainly racist (sub-what?! subordinated?, sub-human maybe?) but, most importantly, it is geometrically and geographically very wrong. The South is not "under" the North: they are all on the same spheroid surface or equivalent cuasi-plane. Even a primary school student knows that!

Anyhow, this is what they have to say in minimalistic terms:

George BJ Busby et al., Admixture into and within sub-Saharan Africa. eLife 2016. Open access LINK [doi: eLife 2016;5:e15266]

Similarity between two individuals in the combination of genetic markers along their chromosomes indicates shared ancestry and can be used to identify historical connections between different population groups due to admixture. We use a genome-wide, haplotype-based, analysis to characterise the structure of genetic diversity and gene-flow in a collection of 48 sub-Saharan African groups. We show that coastal populations experienced an influx of Eurasian haplotypes over the last 7000 years, and that Eastern and Southern Niger-Congo speaking groups share ancestry with Central West Africans as a result of recent population expansions. In fact, most sub-Saharan populations share ancestry with groups from outside of their current geographic region as a result of gene-flow within the last 4000 years. Our in-depth analysis provides insight into haplotype sharing across different ethno-linguistic groups and the recent movement of alleles into new environments, both of which are relevant to studies of genetic epidemiology.



Figure 4. Inference of admixture in sub-Saharan African using GLOBETROTTER. (A) For each group we show the ancestry region identity of the best matching source for the first and, if applicable, second events. Events involving sources that most closely match FULAI and SEMI-BANTU are highlighted by golden and red colours, respectively. Second events can be either multiway, in which case there is a single date estimate, or two-date in which case 2ND EVENT refers to the earlier event. The point estimate of the admixture date is shown as a black point, with 95% CI shown with lines. MIXTURE MODEL: We infer the ancestry composition of each African group by fitting its copying vector as a mixture of all other population copying vectors. The coefficients of this regression sum to 1 and are coloured by ancestry region. 1ST EVENT SOURCES and 2ND EVENT SOURCES show the ancestry breakdown of the admixture sources inferred by GLOBETROTTER, coloured by ancestry region as in the key top right. (B) and (C) Comparisons of dates inferred by MALDER and GLOBETROTTER. Because the two methods sometimes inferred different numbers of events, in (B) we show the comparison based on the inferred number of events in the MALDER analysis, and in (C) for the number of events inferred by GLOBETROTTER. Point symbols refer to populations and are as in Figure 1 and source data can be found in Figure 4—source data 1

Neolithic DNA from Southern Anatolia

I know, I know: I'm decaying into a total procrastinator. I don't have any excuse other than I don't feel like blogging as of late: neither on anthropology nor on politics. I rather feel like learning new stuff and playing, rather than writing and I lack of the structured environment to force myself to do otherwise than what I feel like most of the time. Being of compulsive temperament only worsens things.

I also know that this is not the proper way to start an article. Yes, I know. Do I even care?

So getting to mention now some of the stuff that I have not discussed in these last months and is definitely worth posting about. First of all this key study on more easterly Anatolian early farmers than those seen so far.

Intriguingly they are notoriously similar to those sequenced farther West (see here), what seems to support the model of Anatolian origin of European Neolithic peoples, largely ancestral to modern Europeans. However even Western Anatolian early farmers show already some extra admixture with the Paleoeuropean "WHG" component relative to their Southern Anatolian precursors. So, as the authors suggest, admixture between immigrant farmers and native foragers was a gradual and continuous process beginning in Asia Minor itself.

Gülşah Merve Kılınç, Ayça Omrak, Füsun Özer et al., The Demographic Development of the First Farmers in Anatolia. Current Biology 2016. Open accessLINK [doi:10.1016/j.cub.2016.07.057]

Summary

The archaeological documentation of the development of sedentary farming societies in Anatolia is not yet mirrored by a genetic understanding of the human populations involved, in contrast to the spread of farming in Europe [ 1–3 ]. Sedentary farming communities emerged in parts of the Fertile Crescent during the tenth millennium and early ninth millennium calibrated (cal) BC and had appeared in central Anatolia by 8300 cal BC [ 4 ]. Farming spread into west Anatolia by the early seventh millennium cal BC and quasi-synchronously into Europe, although the timing and process of this movement remain unclear. Using genome sequence data that we generated from nine central Anatolian Neolithic individuals, we studied the transition period from early Aceramic (Pre-Pottery) to the later Pottery Neolithic, when farming expanded west of the Fertile Crescent. We find that genetic diversity in the earliest farmers was conspicuously low, on a par with European foraging groups. With the advent of the Pottery Neolithic, genetic variation within societies reached levels later found in early European farmers. Our results confirm that the earliest Neolithic central Anatolians belonged to the same gene pool as the first Neolithic migrants spreading into Europe. Further, genetic affinities between later Anatolian farmers and fourth to third millennium BC Chalcolithic south Europeans suggest an additional wave of Anatolian migrants, after the initial Neolithic spread but before the Yamnaya-related migrations. We propose that the earliest farming societies demographically resembled foragers and that only after regional gene flow and rising heterogeneity did the farming population expansions into Europe occur.


Autosomal DNA


Maybe the most informative graph is this one (fig. 2):

Genetic Structure and Diversity of Central Anatolian Neolithic Populations
(A) PCA on contemporary west Eurasian populations onto which a total of 85 ancient individuals are projected from this study and previous studies. See Table S1 for number of SNPs per individual. Neighboring modern populations and ancient Anatolian populations are shown encircled. Modern population names are in italics.
Etc. (not so interested here in B, C and D, legend too long, check in the original paper)
Click to expand

It is interesting that, in spite of the Anatolian origin of this ancient ancestral population, they do not tend so much to modern Anatolian Turks but rather to Levant populations like Cypriots (closest ones), Lebanese, Palestinians, etc.

This is probably because, even if early Neolithic peoples of the Levant were not quite like them (see here again) they had become almost like them before the Bronze Age because of regional admixture, which I understand was mostly (but not only) north-to-south flow.

Notice that the Boncuklu (Bon) people had very low genetic diversity and they seem to be a dead end rather than directly ancestral. Instead, the Tepecik-Çiftilik (Tep) population seems a good proxy for the ancestors of Neolithic peoples of Western Anatolia and Europe. 

When we think about South Anatolia Neolithic, we usually think first and foremost about the famous Çatalhöyük site. Well, this ancient settlement is in the area of Boncuklu (to the West, both are near Konya) rather than that of Tepecik-Çiftilik (to the East, near Niğde), so it is quite possible that it is another demographic dead end, related but not directly ancestral to mainline European Neolithic. 

Personally I still think they could well have migrated at least partly by boat, along the southern Turkish coast but, until new data comes, I may need to alter my hypothesis of the ultimate origin being in the Northern Levant (Syria, Lebanon, Cyprus even) rather than Anatolia. These people of Tepecik-Çiftilik were, if not direct ancestors at least very closely related to the actual source population, which may well have lived closer to the coast in any case.



Mitochondrial DNA


The newly sequenced South Anatolian farmers had some of the lineages that were later present in Hungary's and Germany's "Danubian Neolithic", notably the now rare N1a1a1, found in 4/9 samples in this study. Also present were K1a (3/9, incl. one K1a12a), U3 (1/9) and N1a1b (1/9).

So it is time to dismiss the hypothesis that claimed N1a1a1 as a European aboriginal lineage: it came with the immigrant farmers and now there can be no doubt about it.