January 31, 2011

Neanderthal as sprinters?

This is what some researchers from Moscow State University are proposing, according to Russia-InfoCenter. Neanderthals would have been actually specialist sprinters and that was what (allegedly) allowed them to hunt with heavy spears:

The ancient hunter could have crawled towards an animal as close as possible, and then had run as fast as he could, throwing a javelin, while running. However, a heavy spear is much more effective at small distances, than a light javelin. Calculations show that Neanderthal men had been able to cover 15-20 meters within 1-2 seconds, which is enough for a unexpected and successful attack. This means that Homo neanderthalensis were fast and accurate hunters, not clumsy snails as some may think.

Other details of their physiognomy are that they surely preferred to squat above sitting, because they lacked an intermediate layer of fat and muscle on their butts. They also got easily tired of long term standing, the researchers suggest.

Originally from Stone Pages' Archaeo News.

January 29, 2011

Fox as pet 16 Ka ago?

This is more a curiosity than anything else but it'd seem a fox was a pet some 16,000 years ago in Jordan, being buried with its human symbiont. 

Full story at Past Horizons (originally from AiE).

January 28, 2011

Coastal route through Arabia 130,000 years ago confirmed?

A new paper on Arabian archaeological sites is making that claim. So far (Petraglia 2010) we had a limitation with dates only reaching in Arabia Peninsula as early as 90 Ka, while in South Asia and maybe other places these were probably quite older. Not anymore.


The timing of the dispersal of anatomically modern humans (AMH) out of Africa is a fundamental question in human evolutionary studies. Existing data suggest a rapid coastal exodus via the Indian Ocean rim around 60,000 years ago. We present evidence from Jebel Faya, United Arab Emirates, demonstrating human presence in eastern Arabia during the last interglacial. The tool kit found at Jebel Faya has affinities to the late Middle Stone Age in northeast Africa, indicating that technological innovation was not necessary to facilitate migration into Arabia. Instead, we propose that low eustatic sea level and increased rainfall during the transition between marine isotope stages 6 and 5 allowed humans to populate Arabia. This evidence implies that AMH may have been present in South Asia before the Toba eruption (1).

The actual dates collected from the site are of as early as 123-127 Ka (supp. material is freely available).

Location of Jebel Faya and other key sites (dotted line: Pleistocene coast)

Other sources: Eureka Alert, Science Daily.

Related in this blog: Some key archaeological papers on the 'coastal route'.

Orangutans and us

There is a couple of genetic stories on those our red-haired cousins from Indonesia and their genomes, and ours...

On one side A. Hobolth and colleagues call our attention to the fact that parts of our genome are closer to orangutans than to chimpanzees or bonobos, our closest relatives. This does not change anything in regards to our degree of relatedness just tells us of some genes that have evolved in the Pan genus and not in the Homo one.

Refs.: Science Daily story, paper at Genome Research (pay per view).

Meanwhile D. P. Locke and colleagues argue that Orangutan genome has evolved much less than ours or that of our Pan cousins. This is particularly true in regards to Alu elements, which have accumulated very fast in our species, at half that rhythm in Chimpanzees and almost not at all in Orangutans.

Refs. Science Daily story, article at Nature (open).

January 27, 2011

On strike

January 27th is a struggle journey in the Southern Basque Country against the attempts by the Spanish state and the Euro-banksters to demolish the system of pensions... just because... because they will make no money out of this reform: it is just a sign of bowing before the masters of International Capital without any purpose at all.

If they are so needy of budget cuts (lies!), first they should lower the salaries of the king, the ministers, the state councilors, parliament members, generals, subsecretaries, judges, etc. The next one is to cut the military budget: bring the troops from Afghanistan, Kosovo, Bosnia, Ceuta and Melilla, then police budget, and so on.

Ultimately it will be unavoidable to declare bankruptcy, just not to bear the burden of loans, but first of all is to cut the salary of the king, of the prime minister, of the generals and the judges. They can afford a little haircut or a dozen, believe me.

The strike has been extended to other parts of Spain as anarcho-syndicalist, Catalan and Galician unions have joined this call.

But the strike begins now and this blog joins it.

General strike - closed

January 26, 2011

Is X-DNA lineage Neanderthal?

Upon the recent discoveries of Neanderthal and other archaic admixture in modern humans, it arose in the debates occasionally this almost forgotten matter of an X-linked haplotype that looked very much non-African. However Africa had only been sampled poorly back in that time and we lacked any confirmation on this haplotype being present or not in the Neanderthal genetic pool.

According to a new paper this X-DNA haplotype, known as B006, fits well with Neanderthal genetic data and is therefore a likely case of Neanderthal lineage among us.

Frequency of B006 worldwide

It was previously known that the lineage was most common among Europeans and Native Americans, though maybe most diverse in Central-NE Asia. Almost nothing was known then about its presence among South Asians or Australian Aborigines and the little knowledge of the African scatter (mostly among Burkinabe peoples, with one Ethiopian individual as well) has been confirmed, it seems.

But most importantly B006 shares both mutations divergent from the ancestral (Chimpanzee) form among all those analyzed in the Neanderthal genome. One is common to most modern human lineages but the other transition is unique to B006 and the Neanderthal lineage:

In the available Neandertal sequence (Green et al. 2010), there is information on 20 out of 35 dys44 polymorphic sites. These represent eighteen ancestral and two derived alleles, fully matching the corresponding sites of B006 (Table 1). One of the derived alleles, C of  rs6631517, is also shared with other dys44 haplotypes, whereas the second one, G of  rs11795471, is unique to B006 (the information on two remaining B006-polymorphisms is not available).

While not yet fully demonstrated (further B006 haplotypes should be considered along further Neanderthal ones as well), the idea, until now purely speculative, of this lineage being a Neanderthal one, clearly gains strength with this paper's work.

January 24, 2011

Basque History open course

If you are by Bilbao in February you may want to take part in the course of Basque History that will be offered by the veteran People's Institute of Social Studies (GITES-IPES), access to which will be free. 

As Bilboko Branka reports, all conferences will be open access at the Old Quarter's Civic Center ("La Bolsa" building) and are scheduled as follow:

Otsailak 5, larunbata. 9:30etan (Sat. Feb. 5 - 9:30)

“Vascones y sus vecinos en la Antiguedad” (Basques and their neighbors in Antiquity)
  • “El contexto preromano” (The pre-Roman context) Xabier Peñalver arkeologoa
  • “Presencia romana: arqueologia” (Roman presence: archaeology) Mertxe Urteaga arkeologoa
  • “Vascones, visigodos y francos” (Vascones, Visigoths and Frankish) Javier Arce irakaslea

Otsailak 8, asteartea. 19:00etan (Tue. Feb. 8 - 19:00)

“Relaciones y conflictos sociales en los territorios vascos en el marco del feudalismo” (Social relationships and conflicts in the Basque lands in the context of Feudalism), Jon Andoni Fernandez de Larrea irakaslea

Otsailak 10, osteguna. 19:00etan (Thu. Feb. 10 - 19:00)

“Euskal Herriaren Historia merkantilismoaren garaian” (Basque History in the age of Mercantilism), Joseba Zuazo, Historia Modernoaren irakaslea Letren Fakultatean. EHU

Otsailak 15, asteartea. 19:00etan (Tue. Feb. 15 - 19:00)

“Frantziako iraultzatik industria iraultzara Euskal herrian” (From the French Revolution to the Industrial Revolution in the Basque Country), Txema Uriarte Historian doktorea

Otsailak 19, larunbata. 9:30etan (Sat. Feb 19 - 9:30)

“Euskal XX. mendeari buruz: erronkak, itxaropenak eta lorpenak”,  (On the Basque 20th century: conflicts, hopes and achievements) Eneko Bidegain euskal idazle eta kazetaria, eta Josu Txueka Historia Garaikidearen irakaslea Gizarte eta Komunikazio Zientzien Fakultatean. EHU

I understand that the operative language of each conference (Basque or Spanish) is defined by the language used in the original title.

Wiki created

Waiting to be filled with content...

A lot of debates take place here and elsewhere but often I feel the lack of a more solid and encyclopedic goal-oriented repository. Blog posts seldom get any attention for more than a few days (and when they do there's a huge risk that they have become obsolete). So I think a more stable repository is needed.

Feel free to add to it, within the basic criteria of objectivity and neutral point of view. If you need to write subjectively (opinion article), make a subpage on the main subject and describe it as opinion article and sign it (on top).

January 22, 2011

Meditation changes the brain

A new study has confirmed that meditation, reported to increase awareness and calmness, actually does alter the brain. 

Participants in an 8 week meditation program practiced some 30 minutes of the exercises (similar to yoga) every day. As result their brains showed increase of grey matter in the hippocampus (learning and memory) and decrease of grey matter in the amygdala (fear and stress). No change was detected in the insula (self-awareness), reported to have changed in previous studies. The authors suspect that longer practice is needed for this last.

No such changes were detected in the control group, showing that the plastic changes in the brain were caused by the meditation exercises. 

Full story at Science Daily.

Ref. (pay per view): Britta K. Hölzel, James Carmody, Mark Vangel, Christina Congleton, Sita M. Yerramsetti, Tim Gard, Sara W. Lazar. Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Research: Neuroimaging, 2011; 191 (1): 36 DOI: 10.1016/j.pscychresns.2010.08.006

Grape domesticated West Asia

Kambiz mentions today this paper at Anthropology.net:

Archaeological evidence suggests that grape domestication took place in the South Caucasus between the Caspian and Black Seas and that cultivated vinifera then spread south to the western side of the Fertile Crescent, the Jordan Valley, and Egypt by 5,000 y ago (1, 21). Our analyses of relatedness between vinifera and sylvestris populations are consistent with archaeological data and support a geographical origin of grape domestication in the Near East (Fig. 4 and Table 1).

He also mentions that the oldest known wine barrel is from Armenia

I understand that the data of fig. 4 suggest a domestication area between Turkey and Pakistan, with emphasis in the Caucasus region: Georgia, Azerbaijan and Daghestan specially. However Pakistani wild varieties cluster well also and I'd say it cannot be discarded that at least part of the development of this delicatessen crop happened maybe in the context of South Asian Neolithic.

January 20, 2011

Eurasian colonization routes map

Following with the previous post on SE Asia, I just made what is my best hunch of what could have been the migration routes of early Eurasian peoples:

click to expand - apt for wallpaper
No arrows are placed as the routes may have been used biderectionally at times (though the general direction of the migration was West to East, naturally). Flows between adjacent routes were of course most likely to have happened (capillarity not represented) Also I'm a bit unsure about which could be the major routes in Mid and NE Asia specially, so I followed coast and rivers but, if you have any ideas, please let me know.

Zomia and the rivers of SE Asia

I just discovered the concept of Zomia, proposed in 2002 to describe the rather unruly highland areas of SE Asia running from Tibet to the Bay of Bengal and the South China Sea. 

This area has come to the debates in this blog about the Great Eurasian colonization, as it is pivotal between South, Southeast and Mid-East Asia, the main regions of Eurasia where H. sapiens settled early on most likely. But until now I was unaware that it had a name.

The proposed name, Zomia, derives from Tibeto-Burman Zomi (also Mizo), meaning highlander or more strictly remote people

The borders do not exist. As member of a highlander (and yet coastal) people, I reckon that nearby lowlands are typically incorporated into the highlands and vice-versa. Yet the lowlands are also more open to foreign influences, more cosmopolitan and easy to conquer, while the highlands are the backbone of the people. 

So that's why I titled this article Zomia and the rivers... and not just Zomia: the mountains.  Because I do not think they can be detached from each other, at least not easily. 

For the reference: some blogs and media mentioning Zomia: Geocurrents, Loudcanary, Perspectives on Pan-Asianism, Freedom, Understanding Society.

I'm finding difficult to find a good map of the rivers of the area but the satellite map above can give a basic idea. Essentially the Zomia highlands enclose the following rivers:
  • Brahmaputra (by the West)
  • Irrawady
  • Chao Praya
  • Mekong
  • Red River
  • Pearl River (by the NE)
The northernmost implicated river is the Yangtze but this one is a region on its own, alone or with the Yellow and Pearl river basins. 

The main river is the Mekong, which, along the Chao Praya make up the largest lowland area of the whole region and what can be the heartland of Indochina (mainland SEA). But the other river areas also have their own personality. 

Following the premise of "coastal" (tropical) migration model, upon arrival to this area people must have formed several different populations, probably following the river-basins' logic to some extent. Burma (or Myanmar) appears here as a crossroads, allowing people to head northwards into Yunnan, southwards into Andaman and in SE direction into Sundaland (along the coast) and the Chao Praya and Mekong basin (not necessarily by the coast). 

So we can hypothesize at least four different populations resulting from this split after crossing into SE Asia. This is my best-guess reconstruction of the main population flows implied in East Eurasian (and partly All-Eurasian) genesis.

Now feel free to place the major lineages (mtDNA M derivates and all N, Y-DNA D, C and MNOPS) in each of those arrows as you think best. While not indicated there was also at some point a backflow in Westward direction (mtDNA N, R, Y-DNA P). 

I would say that the Irrawady basin (because of its crossroads characteristic) and the Chao Praya/Mekong basin (because of it greater size) must have been areas of certain relevance. However Sundaland and South China (Yangtze, Pearl River and coasts) also look like having played major roles.

January 18, 2011

Linguistic musings: Basque and Proto-Indoeuropean

I'm going through the Swadesh lists for the Western and South Eurasian languages, in order to see if a shared origin (what makes sense from the viewpoint of Prehistory) can be supported with linguistic data of some sort.

By the moment I have gone through the Basque and Proto-Indoeuropean Swadesh lists (with some small sections taken off because they only seem to generate confusion, at least to me). And I notice that  there are at least some rather clear cognates between Basque and PIE:

I compared 111 words, of which 20 look rather likely cognates and some other 13 or 14 are possible remote cognates. That makes c. 30% of possible cognates, what is surely well above my expectations (I had spotted some likely cognates earlier but did not expect so many).

The clear cognates are (eu-PIE):
(2) zu - *túh [you - sing.]
(4) gu - *wéy [we]
(5) zu(ek) - *yū [you - pl.] [notice that 2 and 5 are messed up in both Basque and IE]
(24) hiru - *tréyes (??) [three]
(49) suge - *h₂engwi [snake]
(65) hezur - *h₃ost-, *kost- [bone]
(76) aho - *h₁oh₁s- [mouth]
(77) hortz - *h₃dónts [tooth]
(86) heste - *eh₁ter- [gut]
(103) jaki(-n) - *ǵneh₃-[to know]
(149) izar - *h₂stḗr [star]
(168) hauts - *h₃és-no-, *h₃és-i- [ash]
(170) bide - *pent- [way, road]
(178) egu, egun - *h₂eǵh- [day]
(180) bero - *gʷʰer- [warm]
(184) zahar - *senh₁ó- [old]
(202) -n - (h₁?)en [in, on]
(207) izen - *h₁nḗh₃mn̥ [name]

Add to these at least the verb to be (not in the list): iza(-n) - *es(t)-

And add also two special cases from the list, yet quite clear:

(92) edan (to drink) - (93) *h₁ed- (to eat)

The change of meaning is quite acceptable, specially if we imagine the common ancestor to mean "to ingest" without liquid or solid connotations.

The other case is PIE (171) *gʷerh₃- (mountain), which I am almost persuaded it has something to do with Basque gora (up, upwards), which has a clear Basque etymology (goi-ra). It may be a coincidence or a strange case of lending but this has been haunting me for more than 20 years now since I learned some Serbocroat words, including gora (mountain) and gore (up, upwards). And now comes back in form of PIE reconstruction.

The less clear, potential, cognates would be as follow:

(28) luze - *dluh₂gʰós [long]. This I have generally suspected as a loanword from some IE language to Basque, but the main reason for this suspicion is that it begins like the usual IE words for long (long, largo, etc.) with an L-. There's nothing else, however the connection seems more real when you go to PIE.

(33) labur, motz - *mreǵʰú- [short]

(50) har - *wrmi [worm]

(57) erro - *wréh₂ds [root]

(62) azal - *pel- [skin]

(68) adar - *keg-, *ḱer- [horn]

(71) ile - *pulh₂- [hair] [this one seems to be related to 62, maybe *Vl(e) meant once skin and hair alike (or as conceptually highly related words) - we can still discern an open vowel (a/e) in 62 and a closed one (i/u) in 71]

(72) buru - *gʰebʰelo- [head] [where *gʰeb- corresponds with the other proposed root *kaput, and -bʰelo- would correspond with Basque buru]

(78) mihi - *dn̥ǵʰwéh₂s [tongue] [probably not but still I do see some similitude]

(104) gogo(tu) - *tong- [to think] [here the Basque list reads pentsatu but this is no any genuine Basque word: gogo as noun means psyche, mind, soul, desire, and gogotu means to wish but also any other mental function, however it's been partly replaced by Spanish loan pentsatu for rationalist uses mostly]

(172) gorri - *h₁rewdʰós [red] [I have before mentioned the importance of the sound R in West Eurasia to describe the color red: it's not universal but it's much more common than in East Eurasia or anywhere else I could check]

(179) urte - *yeHr-, *wet- [year]. Check also (194) PIE *wed [wet]. In Basque urte is clearly related to the water (ur) cycle and watery (not wet but close enough) would be urti.

(180) lehor - *ters- [dry]

Now the disclaimer: this are nothing but a bunch of notes for my (and potentially also your) interest. No theory is proposed, no systematics is being used, it is just a free exploration.

However I was drawn to this exercise, which is just the first two rows of  many others, because I suspect that West and South Eurasian languages (excluding Uralic and Afroasiatic, which are of different origins) may share a common origing c. 50 Ka ago. Specially if both IE and Dravidian infiltrated South Asia after the Neolithic.

On the contrary I dislike quite strongly pan-north-Asian conjectural superfamilies, specially Sino-Caucasian, which makes no sense whatsoever on light of all I know about Prehistory.

In any case, something to chew on.

Update: Octavià mentions a couple of references of other (presumably more knowledgeable) people who have in the past suggested a Basque-IE connection:

Arnaud Fournet, Comparing Basque and Proto-Indo-European: a preliminary phonetic survey. He finds some of the same connections I mention here but he goes further into terrains that are too obscure for me to assess properly.

Arnaud Etchamendy has a whole site dedicated to "demonstrate" that Basque is Indoeuropean (a bit too far in my opinion but anyhow).

I must say that, against my own expectations, a preliminary survey  I made of Basque, IE, Dravidian and NE Caucasian, seems to reinforce the idea that Basque and IE are related, more than to the other considered languages. See comments section for some more details (all this is very raw and tentative admittedly).

January 15, 2011

Selection in looks?

A new research paper finds that many genes involved in appearance have rather clear indications of positive selection.

From the Abstract:


Here, we study the level of population differentiation among different populations of human genes. Intriguingly, genes involved in osteoblast development were identified as being enriched with higher FST SNPs, a result consistent with the proposed role of the skeletal system in accounting for variation among human populations. Genes involved in the development of hair follicles, where hair is produced, were also found to have higher levels of population differentiation, consistent with hair morphology being a distinctive trait among human populations. Other genes that showed higher levels of population differentiation include those involved in pigmentation, spermatid, nervous system and organ development, and some metabolic pathways, but few involved with the immune system. Disease-related genes demonstrate excessive SNPs with lower levels of population differentiation, probably due to purifying selection. Surprisingly, we find that Mendelian-disease genes appear to have a significant excessive of SNPs with high levels of population differentiation, possibly because the incidence and susceptibility of these diseases show differences among populations. As expected, microRNA regulated genes show lower levels of population differentiation due to purifying selection. 

While the paper does not seem to suggest why these patterns of inter-population differentiation are stronger in the genes of appearance mostly, I'd say that the selection involved is directly social and sexual and largely the same pattern by which races appeared and are maintained (to some extent). Intuitively people tend to favor statistically more those who look like themselves of people they know and have good opinion of. That way certain looks or family air are sustainedly favored within each population (the son who looks more like the father, the person who looks more sexy according to certain parameters, largely socio-cultural, etc.) producing eventually what we call races, more apparent than the actual underlying differences between populations, which are invariably much smaller than it looks. 

Austroasiatic peoples of India: the autosomal DNA

An interesting paper published online in October 2010 (official publication date is however 2011) but that I had not visualized to date is:

My head is still dizzy from the pains of quitting up heavy smoking without any help whatsoev (and without the real conviction of it being worth the effort, just bored of going through an unhelpful and demanding bureaucracy of self-righteous institutionalized robbers and drug dealers to get my dose), so I won't extend much upon this one. 

Most importantly it comes up clear that Indian Austroasiatics are, in spite of often obvious East Asian male-mediated ancestry, mostly South Asian by overall ancestry:

Fig. 3 - PCA and K=7 analysis

In the structure analysis, we see that the main component (black) of Indian Austroasiatic speakers is shared with Dravidian populations of South India (but not Brahuis, who are typical Pakistanis in spite of speaking a Dravidian language). This component is also shared at lower frequencies by South and SE Asian populations. 

This is also apparent in the PC graph, where Indian Tibeto-Burman peoples cluster with East Asian ones but not Austroasiatic Indians, in spite of some lesser tendency in that direction.

In an aside, it is also notable to mention that the North Indian component (green) is clearly different from those in West Eurasia, even if there is a lesser presence of this South Asian component. This rather goes against those who claim that North Indian/Pakistani specificity is of West Eurasian origin: if anything some West Eurasian element would need to be explained as originating from South Asia. The only WEA population lacking it are, as usual, Basques, indicating it is at least a marker from outside Europe and, in Europe, surely marks Neolithic or Metal Ages (Indoeuropean) arrivals.

Back to Austroasiatics, it is worth quoting this:

The mtDNA haplogroup allocation of Munda speakers is similar to Dravidian and Indo-Europeans of the Indian subcontinent (Basu et al. 2003; Metspalu et al. 2004; Chaubey et al. 2007; Chaubey, Metspalu, et al. 2008; Chaubey, Karmin, et al. 2008; Thangaraj et al. 2009). We carried out a high-resolution analysis of those haplogroups of Munda speakers, which account for >4% of their maternal gene pool. All the seven maternal haplogroups found frequently in Munda speakers are autochthonous to India (supplementary fig. S5, Supplementary Material online) (Chandrasekar et al. 2009) and references therein, accounting altogether for 57% of the maternal gene pool of present Munda speakers. The extensive analysis of these haplogroups revealed relatively recent sharing of most recent common ancestors within these groups between AA and non-AA speakers (MRCA), suggestive of admixture; a similar result was observed recently for hg R7, which is the most frequent among these in AA speakers (Chaubey, Karmin, et al. 2008). The mtDNA lineages of Munda speakers do not cluster in basal parts of the tree (to founder haplogroups M, N, or R) but are spread among the derived branches that date to <10KYA (Supplementary fig. S5, Supplementary Material online) suggests that the mtDNA diversity found in contemporary Munda speakers is the result of admixture from neighboring populations of India.

In sharp contrast, among the geographically proximate Khasi-Aslian–speaking Khasi population, approximately one-third of the mtDNA lineages have southeast Asian ancestry (Fig. 2 and table 2).

Having these distinctions present is important to understanding what in these peoples related to SE Asia, is autochthonous from South Asia or recent (Neolithic) immigrant from SE Asia.

January 12, 2011

Romani mtDNA

There is a new paper onthe genetics of the Roma People (Gypsies), with emphasis in mtDNA:

The lineages of this European people of South Asian origins can be divided in a clearly South Asian component (M5a1 specially, also M18, M25 and M35b), a most likely West Asian component (X2 and J1 clades specially), a possibly Balcanic component (H7 and U3) and "others" (clearly European lineages). The exact apportions vary among populations as follows:

Fig. 1

I think it is interesting demonstration of drift and founder effect how most pre-Europe "founder" lineages have vanished in most populations, specially in the rather well known "bottleneck" leading to non-Balcanic Roma: of all the Indian lineages almost only the largest one, M5a1, survives beyond that bottleneck. The same happens with West Asian X clades (barely surviving among Polish Roma).  Instead other lineages have been amplified in destiny regions, no doubt by founder effect. This is particularly true for U3 but also H7 and some of the J1 clades and even an Indian lineage barely found in the Balcans (M18, which has thrived in Spain instead).

If you now compare Spanish or Lithuanian Roma with the Bulgaria 1 sample (probably the one best representing the ancestral Roma, at least in their "founder" lineages fraction), it is almost difficult to recognize much affinity. Only M5a1 remains as a clear link. The Bulgaria 3 sample (Vallachian Roma arrived to Bulgaria in the 19th century) is maybe a more clear ancestral link but still the differences are notorious.

Indian origins

The authors argue, on statistical methodology (table 3), on a Punjab origin for the Roma, which is consistent with their language. However, as Manju points out at his blog, this is not so consistent, it seems with their patrilineages, which are probably from SE India, lacking R1a1, the most common NW Indian lineage (and I would add R2, L, J2, etc., all of which were in India some 2000 years ago when the Roma exodus must have happened, at the earliest).

Actually the state of Orissa has also high statistical likelihood for the origin of the Roma people, being only second to Punjab by the authors' methodology. Also the main Roma founder mtDNA lineage, M5a1, is much more common in SE India than in the NW. This is also true for M18.

Fig. 3
So it is surely worthy to consider, as Manju does, whether the proto-Roma are ultimately original from Eastern or SE India, although incorporating lineages maybe from the NW, such as M35b, the same that they later did in West Asia and Europe. 

In this sense it is maybe worth considering in future studies comparing with the Domba people of South Asia and the Dom people of West Asia, generally considered to be likely relatives of European Roma.

January 11, 2011

Mitochondrial DNA of West Europe

Maria Lluïsa, of NeanderFollia[cat], points me to this interesting paper:

I am unsure about the access status of this particular paper, but at the moment of writing this, it is openly available online as advance online publication

Most interesting is surely the quite important database (mtDNA) covering most of West and Central Europe, from the Northern parts of Spain to Denmark and Poland (including many populations from France), available in the supp. material table S3.

Some fun with bidimensional representation

Let's begin the linearized Fst distances in a bidimensional graph (colors are mine, see below):

(click to enlarge)
In order to clarify a bit all that nightmare of acronyms, I marked Basque and Bearnese samples in red, those from the Paleolithic Franco-Cantabrian region in orange and those from the Rhine-Danube region in blue. The larger orange dot FCT is Perigord (Dordogne), the most important single district of Paleolithic Europe. 

You can maybe guess some of the simpler acronyms such as ENG (England) or AUS (Austria), I won't list them here (they are in the supp. material) but I must say for clarity that all beginning with F are from France, initial G means Germany and initial I means Ireland. All the others have unique areal acronyms and those ending in MI mean "miscellanea". 

Not much apparent structure is observed: basically there is a big blob in the middle (albeit divided in two not too well defined subclusters, I drew a dotted line to mark this internal division) and then four very isolated samples that actually describe the two axis of the graph. 

These "polar" samples are the following ones:
  • ALA is Araba (Álava in Spanish), a Southern Basque province mostly looking to the Upper Ebro. It defines the positive polarity of the first dimension and its main characteristic is to have 80% R-CRS (surely all H).
  • PAS is Valle del Pas (Cantabria), a mountainous district famous for its soft cheese biscuits, its religious architecture and the frequent visits of geneticists... to their archived data (a pity because they miss the delicious quesadas). They define the negative pole of the first dimension. They are particularly high in haplogroup V (24%) but low in CRS (27%). They are also high in U5 (13%), I (6%) and T2b (8%).
  • GUI is Gipuzkoa (Guipúzcoa in Spanish spelling). Their most salient characteristic, as far as I can tell, is an unusual high frequency of H2a (22% within H, 12% of all). They also have rather high frequencies of V (12%) and U5 (17%) and are quite to very low in the Neolithic clades (J, T, K, W, X).
  • COR is Cornwall. Their most notable characteristic is very high J (20%).
It is curious that all the first dimension of West and Central European diversity is synthesized in a line of some 50 Km or maybe a little more just SW of where I live. The authors seem to agree:

Northern Iberia appears to be microgeographically differentiated. Excluding the highly divergent Pasiego isolate (Maca-Meyer et al., 2003), there are also significant differences between the Basque provinces or between Catalonia at the north-eastern edge and Galicia-Asturias in the northwest. In fact, when these results were represented in an multidimensional scaling plot (Figure 2), the Pasiegos and Spanish Basques from Guipuzcoa and Alava were the most outstanding outliers, also followed by samples from Catalonia and Galicia, the French Basque sample and the British samples from Cornwall and Wales.

Even if we decide to disdain the extreme Araban and Pasiego samples, the next in line marking this polarity are Bearnese/North Basques (FSW) and Catalans (CAT), what implies a somewhat longer line from ESE to WNW along the Pyrenees. Somewhat different in the direction and distance but not too much in the geographical regions involved.

The second dimension is  quite different, defining a S-N axis along the Atlantic coasts of France, between Cornwall and Gipuzkoa. After ignoring the outlier poles, we can redefine this second dichotomy as being between West Ireland and Cantabria or something like that (same axis mostly, though moved to the West a bit).

The two main clusters show tendencies in these two axes: one (low, left) tends to Cornwall and the Pasiegos (or Catalans if you wish), while the other (up, right) tends to Basques (Arabans and Gipuzkoans specifically). The clusters are not too well defined anyhow and there is also a smaller third cluster formed by Biscayans, Provenzals and Cantabrians, which stands between the Pasiegos and Gipuzkoa (what, excepting the Provenzals, makes almost perfect geographic sense).

I have tried to represent the findings from the Fst graph in maps:

1. The polarity axes: red is dimension 1 (dotted line after replacing Pasiegos by Catalans) and blue is dimension 2:

It is... curious, right?

2. The clusters: blue and red are the populations in each of the two main clusters, marked with stars the four "polar" or outlier populations, with colors representing the cluster they are closer to. Green is the third minor cluster. Magenta are two populations (Switzerland and Morbihan) for which two different samples exist and each falls in a different cluster. I ignored the "miscellanea" samples.

If we are to hypothesize a Franco-Cantabrian origin to some of this duality (which is surely more complex than just that), we'd see that northern Franco-Cantabrian populations (Dordogne, Herault and Lyonais) fall in the blue cluster, together with several Atlantic populations from France, Scotland and Ireland, the Danubian fraction of  Central Europe and the Mediterranean fraction of Iberia. 

The red cluster instead looks more specifically Atlantic, with Basques/Bearnois and Asturians being the only ones from the Franco-Cantabrian region and otherwise being concentrated towards the North-West.

The lesser green cluster is totally Franco-Cantabrian but should represent a peculiar intermediate alchemy rather than a distinctive ancestral group, I suspect. Not that the other larger clusters are safely any representation of shared ancestry necessarily either but at least of some intriguing coincidence in their alchemy that seems to ask for further exploration.

Some intriguing details of specific haplogroups

The authors seem to take a critical stand, based in previous work, on the Franco-Cantabrian or even Catalan origin of haplogroup V. Different papers have offered strikingly different results on the frequency of this clade specially in Catalans (earlier claimed to be 24%,  now just 3%) and Gipuzkoan Basques (initially said to be 20%, now more like half that amount). García and colleagues seem to hint that V may have a southern Iberian origin after all:

Diversity values for V are significantly higher in Southern Iberia than in the Cornice (P<0.05). Excluding Scandinavia, the lowest diversities are found in Northern Africa and the Iberian northeast.

I say that this would totally fit in my model of important Ibero-African contacts in the context of the Last Glacial Maximum and the genesis of Oranian culture in North Africa. It is also consistent with the known fact that North African mtDNA H (sister of V, together making up c. 30% of North African mtDNA) is of Iberian or otherwise SW European derivation. 

There is also some mention to HV4, with a novel sublineage, HV4a1, of apparent origin in the Cantabrian strip (also found in one Italian and one continental European). Other HV4 sublineages are Eastern Mediterranean however, with its closest relative HV4a2, being found in Jordan and Egypt. 

In regards to H, it is worth mentioning the general high frequencies in the Cantabrian strip and specially high frequency of H6a among Cantabrians (12%), however it lacks diversity. 

H7 is confirmed as being most frequent in NE Iberia and SE France, it is one of the four H subclades with significant presence in North Africa as well. The authors however yield to the Mediterranean origins temptation, claiming presence in West Asia that is actually quite anecdotal (4/253 per Enafaa 2009). Excepting Catalonia, H7 is rare in Iberia but it is quite common in France instead, where it is largely concentrated (Álvarez-Iglesias 2009). The newly revealed presence in Catalonia offers a plausible origin for its North African presence in the context of the LGM transmediterranean contacts, which would be quite parsimonious considering that in general all mtDNA H in the region is of Iberian origin (Cherni 2008). But whatever. 

A key haplogroup however is H1, the largest H sublineage. In this aspect the authors find surprising heterogeneity. While the highest frequencies are in the Cantabrian strip, the highest diversity seems to be in the Mediterranean area (Italy and Balcans). Next in line come Scandinavia (Finns included), NE Europe and North Central Europe, all three tied at the same value (9.4). Paragroup H1(xH1a,H1b) appears to have also greatest diversity in Italy-Balcans, followed Scandinavia and then the Western Islands and NE Iberia (Catalonia and Aragon). H1a is clearly most diverse in NE Europe and North-Central Europe. H1b, a smaller scattered lineage, is most diverse in the southern Iberian Peninsula. Within H1:

FST pairwise comparisons based on haplotype frequencies detected unexpected heterogeneity. France showed close affinities with only the nearby north-east Iberian sample. In addition, the Scandinavians seem to be very different from north-central Europeans, showing more affinities to Slavs.

H3, the second largest H sublineage probably, is most diverse in North-Central Europe, in spite of being much more common in SW Europe (3-8%).

All this suggests that haplogroup H spread to SW Europe from Central Europe and not the other way around. At least H1b has been detected in Epipalelolithic Portugal (Chandler 2005, revised sequence assignment by me) establishing a maximum date for this spread. I would therefore think that mtDNA H subclades expanded at the latest with the Gravettian wave because there are no more cultural flows towards SW Europe with that origin before the late Bronze Age (or the late Chalcolithic if you wish to consider Bell Beaker - not me).

It is quite surprising anyhow to find such relative low nucleotide diversity levels for these so abundant clades not just in the smaller NW and NE Iberian regions but specially in France, while South Iberia generally shows greater diversity instead. The results raise more questions than provide answers in this sense.

Recently described haplogroups H1r and H1t were found to exist among Basques. H1t seems to be an Iberian-exclusive clade, while H1r seems instead continental (found in one French and one "European", as well as one Basque now). 

In partial contrast haplogroup K has highest diversity in NE Iberia. However the differences are not too large for all Europe except the NE, where diversity is very low. 

T2b has highest diversity in Northern Iberia (both NW and NE), followed by North Africa.

Excluding two too low in number, the greatest diversity of W is in Balcans-Italy, followed by Iberia (all three regions).

Franco-Cantabrian post-Glacial expansion?

Apparently not. This seems the main conclusion from this paper and, on light of the perplexing diversity values, even for H3, I have to agree. H arrived here from Central Europe and probably Italy, already diversified to a large extent, and did not move much after that. This arrival probably happened in the Gravettian or Aurignacian periods.

It is however still possible that a male-biased expansion happened with Magdalenian, as suggested by the patterns of R1b1b1a1a2, the most common R1b sublineage, at least in Europe, which seems to have most of its phylogenetic diversity (safer than nucleotide diversity, which is the one analyzed by García et al. in the mtDNA) around the Pyrenees (see here). However a local Central-North European component is still evident in its smaller brother haplogroup R1b1b1a1a1.

Another caution is that no meaningful sampling of French mtDNA has been undertaken since 2004 (Dubut et al., data recycled for this paper) and, considering the many errors and flukes happening in other cases without enough second and third samplings, it is very possible that a lot is still hiding in that area, so important in European prehistory.

January 10, 2011

Working on a free repository of info on prehistory and genetics

As you may know, I do not collaborate with Wikipedia anymore (since years ago) on ideological reasons. But I do feel that that a wiki on human prehistory and genetics is something almost necessary. 

So I looked up wikifarms and found one that is free and does not use adverts (they request donations hence, of course). Also they seem to have a quite libertarian (as in anarchist, i.e. free and cooperative) philosophy. Hence I have created an account and submitted a project to OurProject. They will reply, hopefully in approval, in 72 hrs. (three days) and I'd like to begin working in it as soon as it is ready. 

So, even before the project is available to begin working with, I want to ask to the readers of this blog if they would be interested in helping with creating quality unbiased content on these matters. I think I can produce some quite decent stuff alone but slowly but it'd be much better and faster with other collaborators.

While I do not understand yet quite well the details, I see in their documentation that they emphasize multilingualism to at least some extent, so, if you are not fluent in English, this should not be any major obstacle. However my priority is of course in the modern lingua franca, English.

I chose as license type public domain, what means that any collaboration automatically becomes owned by 7 billion people altogether on this planet. There was a host of licenses to choose from (though no private copyright or anything like that) but I think public domain is simplest. 

While I have not thought much in further details, there are some things I have in mind already:
  • Comprehensive and as objective as possible pages on each of the haplogroups, including relevant paper references and known distribution and phylogenies.
  • Dumping some of my best maps there, so they are not just in my blogs.
  • Mapping archaeological cultures throughout the World.
In brief, gradually building a comprehensive repository, available to all for free, on human origins, emphasizing objectivity and neutral point of view. As no current affairs/politics are directly involved this should not be a big deal, however I am also considering, if possible and compatible with the project, the existence of distinctive, signed and clearly marked as such, opinion articles if someone feels the need. But my priority is to gather all or most relevant information in a publicly available site. 

What do you say?

Update: the project has been approved and it should be available withing 6 hrs. The address is http://humanorigins.ourproject.org/  and the full title is Human Prehistory and Genetics. As far as I understand, you need to create an account with this project in the corresponding field (the full name) in order to be able to edit the wiki. However I am still a noob and I will need some practice before I become acquainted.

Actually you may need to create an OurProject account, visit this page and request to join. 

Policies and administration privileges will be discussed as need arises and we see who is taking the wiki seriously. I just realized that there is the possibility of having more than one license but all are in the line of open access (no private copyrights) - also to be discussed as need arises.

Update(2): I have (as recommended) categorized the project as:
  • Topic: Encyclopedia, Archaeology and Anthropology (3 categories are possible and there was no "genetics" one)
  • License: Public Domain (two other can be added, probably Creative Commons is a good idea)
  • Natural language: English (two other can be added but I wonder how to work in multiple languages)
  • Status: planning (to be changed to initial development as soon as something is in)

Update - Jan 11

I managed to figure out how to create a "MoinMoin" wiki within the main OurProject wiki. (LINK, feel free to edit with good reason - create a user first anyhow prefereably). This is however quite disappointingly complicated to manage (of course it may depend on your expectations but I am used to Wikipedia and other user-friendly GUIs).

There is the possibility of uploading some wiki software to the main subdomain but I fear I am not sufficiently techy for that (at least not yet).

    January 9, 2011

    Atapuerca Director: Tel Aviv teeth are Neanderthal or similar. Judeo-Christian bias blamed for the hype

    José María Bermúdez de Castro, Director of Spain's National Center for the Research of Human Evolution (the "Atapuerca team"), writes today at Público newspaper[es] clarifying the matter: the human teeth found near Tel Aviv and hyped in the media as the first humans and blah-blah... are Neanderthal or quite so. 

    Some key excerpts (my translation and bold type):

    (...) the authors offer three similarly likely hypothesis to interpret their findings. But then they adopt the one that can offer more notoriety and discard the one that, in my opinion, is the most likely one, judging from the excellent images of the findings. The teeth are very similar (if not identical) to those of Neanderthals (...)

    Eight teeth cannot be enough argumentation to demolish a hypothesis supported by dozens of works made in the fields of palaeoanthropology and genetics. I am persuaded that the authors are well aware of this. (...) Some media have been carried away by the symbolism of the region and of the Christmas period. I am afraid that some 400,000 years ago God did not inhabit the minds of human beings, or at least there is no data supporting such hypothesis.

    I was admittedly waiting for some Atapuerca expert to demolish the wild and so-blatantly superstitious and populist conjecture. I did not have to wait much, thanks Jose Mari and thanks to Fonso for the link (at Mundo Neandertal[es], comments section).

    Dalmatia as a central hub for South European Neolithic

    I cannot find the relevant paper and I am not sure how this news item is different from what we already knew, though it is true that the Eastern Adriatic region, at the origin of Cardium Pottery Neolithic is often ignored and misunderstood, with the focus often being in Central and East Balcanic Neolithic and its derived variant in Central Europe: the Danubian Neolithic (Linear Pottery culture, LBK).

    Yet at least as important as these was the Mediterranean Neolithic and, for this, it all began in Dalmatia and nearby areas (Bosnia, Montenegro, coastal Albania), soon spreading to Italy and beyond, to SE France, the coasts of Iberia and some coastal enclaves in North Africa. 

    The news item I am referring to is at Science News today and it has some interesting paragraphs, obtained from archaeologist Marko Mendušic and his US colleague Andrew Moore:

    Their discoveries support the idea that agricultural newcomers to southern Europe built villages without encountering local nomadic groups, Moore asserts. Earlier excavations at Neolithic sites in Germany and France raise the possibility that hunter-gatherers clashed with incoming villagers in northern Europe, he notes.

    Surprisingly, Pokrovnik and Danilo Bitinj residents grew the same plants and raised the same animals, in the same proportions, as today’s Dalmatian farmers do, Moore says. Excavated seeds and plant parts show that ancient villagers grew nine different domestic plants — including emmer, oats and lentils — and gathered blackberries and other wild fruits.

    Animal bones found at the two villages indicate that residents primarily herded sheep and goats, along with some cattle and a small number of pigs.
    This dominance of sheep and goat herding, along with all the classical array of Neolithic domesticates in the wider region, is a characteristic of Mediterranean Neolithic.

    Aside from farming, Neolithic villagers in Dalmatia were “oriented toward the sea, and enjoyed extensive long-distance contacts,” Moore adds. Chemical analyses of obsidian chunks found at Pokrovnik and Danilo Bitinj, directed by archaeologist Robert Tykot of the University of South Florida in Tampa, trace most of them to Lipari, an island off Sicily’s north coast.
    This seafaring inclination, not fearing even the high seas, is another characteristic of Cardium Pottery Neolithic. 

    Of course, the third trait is their unique pottery (left: an example from Catalonia), not painted but imprinted, often with the shell of what used to be the genus Cardium, now superfamily Cardidae (cockles in English, berberechos in Spanish and Galician, escopinyas in Catalan, berbigoes in Portuguese, cocques and bucardes in French). 

    However both in the original area of the Western Balcans and in the extended area of Italy and the West Mediterranean, soon the pottery styles evolved into other forms known as a whole as Epi-Cardial. 
    There is also some presence of this pottery in at least one of the earliest Greek Neolithic sites, Otzaki, and later also in Lebanon and coastal Syria (Byblos facies of the Amuq-Byblos culture), where it must have arrived from Europe (because of the rather late time frame).

    The expansion of this Neolithic culture is, with some exceptions, characterized by the assimilation of earlier populations, something evident in the continuity of local Epipaleolithic toolkits. 

    January 8, 2011

    Archaeonews: South Iran and South China Neolithic findings, London's oldest artificial structure

    Some interesting snippets from Stone Pages' Archaeo News section:

    Southern Iran's findings from 5000 years ago

    Teheran Times reports the finding of a a site related to Jiroft culture.

    The site, Kajeh Askar, near Bam (Kerman province) was discovered during emergency digs because of a road construction. Part of the site was damaged while excavating. 

    Among the findings are pottery and two burials, one in fetal position and another in extended face up position.  These bodies had been interred with diverse artifacts, including a seashell apparently used to store cosmetics. 

    New Neolithic culture from Jiangxi, China

    A new Neolithic culture has been named in South China as Terracotta and Painted Pottery Culture. The site is known as Lahodun and is near Gaohu (Jiangxi). 

    The finding includes stone walls and tools (hatchets, adzes, ploughs) as well as pottery and are preliminarily dated to c. 6000 years ago. Archaeologists also report a large sacrificial table made of high purity yellow clay (3000 m², up to 80 cm thick), 114 so-called sacrificial tombs and a structure made of red scorched earth.

    London's top secret

    The nickname comes because the newly found wooden structure is right in front of the headquarters of the infamous British secret service MI6. The archaeologists even had some trouble when the wannabe James Bonds suspected that they were planning some sort of attack.

    Fortunately the dig and topographical measures could proceed normally after the misunderstanding, revealing a wooden structure, which is neither straight nor round but could well have served to support a platform on what was then a small island within the Thames river. 

    The site is dated to c. 7000 years ago, in the Epipaleolithic period and is the oldest known structure in the English capital.

    As always you can discuss these news and more at Archaeo Forums.

    Clothes, lice, Homo sapiens and Neanderthals

    New genetic research on clothing lice and its relative hair lice, using molecular clock estimate methods, suggests that our ancestors began using clothes only some 170,000 years ago, roughly the age of Homo sapiens as distinct species per the archaeological record. 

    But the usual warning of all molecular clock estimates applies (with special emphasis, see below).

    Loss of body hair is estimated to have happened c. 1.2 million years ago, in the H. ergaster phase, or arguably even earlier based on the genetics of pubic lice (3 Ma.) However it seems now that people did not use clothes until much later.

    Or at least people within the H. sapiens lineage...

    Fig. 1

    Notice please the first evidence of hide scrapers in the graphic above: it is a clear indication of working skins. Of course skins may have been used for other purposes than just clothing, like containers maybe...

    However it is worth noticing that this reference directs to Carbonell 1999, which discusses the archaeology of Atapuerca, a famous Iberian site related to Neanderthals and their predecessors. In Europe the need for clothes was much more urgent obviously and the ancestors of Neanderthals got to work on it out of need.

    I'd like to know when are dated the first scrapers from Africa because I do not think they are so old. Are they? Obviously in Tropical Africa, the evolutionary homeland of our species, the need for clothing was almost none. Even today many peoples live almost or even totally naked in Sudan, while in India, many religious people do as well and in Papua clothing is often just a penis cover (or delusional enhancement maybe) out of a gourd. 

    It is worth mentioning that this paper incurred in the common error of calibrating using Chimpanzee louse as outgroup, attributing to the Pan-Homo divergence the lowest possible age per the literature: 5.0 to 5.5 Ma. (when we know it is of at least 8 Ma.) Hence the age estimate should be multiplied by 1.45 or 1.6, getting a more likely age of at least 250,000 years for the coalescence of modern clothing lice and hence use of clothes by our ancestors (excepting probably Neanderthals). 

    At that time (all of them) we were still living in Tropical Africa. Why would people begin to use clothes then? I am hunching here that maybe there was some need in order to colonize or otherwise exploit the Ethiopian highlands. Certainly the oldest fossil generally acknowledged as Homo sapiens, dated to c. 190,000 years ago, is from the southern slopes of that impressive massif. Also this area between Ethiopia and Southern Sudan looks to me, based on mtDNA spread, a most likely candidate for the original homeland of our species.

    Location of Omo (black bubble) on a topographical map of Ethiopia

    Exploring the ancestry of African-Americans

    Preliminary note: in this post African-American means people of African descent living in America (aka the Americas), not just people from the USA.

    The authors acknowledge that they find difficulties in tracking regional African ancestry because of the limited genetic data available for this continent, with some important countries in the Atlantic slave trade, like Ivory Coast or Ghana, being still largely not researched. The situation may be even worse for Y-DNA and autosomal markers.

    I'd say that this sad situation is product of several factors: first of all lack of interest by Western or Asian researchers, then unequal access to the DNA pools of the continent, often for political reasons (this happens elsewhere, specially in parts of Asia but also in France), other factors are the huge size and diversity of Africa and its population and the relative lack of obvious structure, with many lineages scattered across the continent. This last element actually seems to demand greater research and finer-grained haplotyping but this only comes in small drops. 

    Inter-continental admixture, the well known sex-bias

    A simpler analysis can be done in regards to inter-continental admixture (fig. 1):

    Fig. 1 - Ancestry of African-Americas: (a) mtDNA, (b) Y-DNA and (c) autosomal DNA
    We can see in these maps, for example, that Afro-Brazilians are largely of European and Native American ancestry (c), even if African descent is still dominant.  We can also see that European ancestry is overwhelmingly of male lineages (b), while Native American one instead is almost only of female origin (a). 

    This seems quite peculiar of Afro-Brazilians, with no other American population displaying such pattern. Although it may be arguable in the case of Afro-Caribbeans. The population displaying most European female ancestry are African-Americans from Philadelphia.

    Notice that minor European and Native American components are present in the autosomal samples of pure West Africans, indicating that these minor amounts are actually imprecisions of the clustering method. 

    In the reverse direction, there is a map (fig. S1) in the supplementary materials that shows important African and Native American ancestry among white Brazilians, again showing sex-bias in the admixture, with nearly all being attributable to female ancestry. Some admixture is also apparent in white Philadelphians but it is much smaller.

    African regional ancestry estimates

    But the greatest effort of the authors of this paper is trying to unravel the African regional ancestry of these populations. For this they had to resort to mitochondrial DNA, which is admittedly just part of the whole picture and is often not sufficiently well structured by regions anyhow:

    Fig. 3 regional African ancestry estimates (mtDNA)
    The impression we get is that SE African (Mozambique) and Gabonese ancestry is restricted to South America. Instead Cameroon ancestry is concentrated towards the North of the new continent. Angolan and West African ancestry are widespread, however there is no detected Angolan ancestry in the former Spanish colonies. 

    The authors argue some of these differences based on the chronology of the Atlantic slave trade, that in its first phase almost exclusively preyed in Westernmost Africa and Angola, while looking for other sources West-Central Africa and Mozambique in its late phases.

    West African insular peoples

    A map available in the supplemental material, fig. S6, also addresses the matrilineal ancestry of the populations of Cape Verde and São Tomé, two insular areas uninhabited before the colonial period and settled essentially with slaves from the continent (though Cape Verdeans  specially also have some important European admixture, less important probably in São Tomé). Cape Verde African ancestry is exclusively from Westernmost Africa, including Mauritania, instead São Tomé shows a mixture of Westernmost Africa and Central Africa (Gabon, Angola), to the exclusion of the Nigeria-Cameroon area.