Out of Eden: The Peopling of the World (21 page)

Figure 3.1
   Map of the suggested routes of spread of Aurignacian pioneers into Europe before 37,000 years ago. Only the earliest Aurignacian sites are shown (filled dots) – the dashed line represents natural routes along rivers, lowland and coast joining the dots. A parallel route from the Zagros to Karabom in the Russian Altai is shown.

The Aurignacian cultural tradition persisted in some form or another until much later and in due course became more unequivocally identified with modern human skeletal remains; but this early, rapid spread into regions which had previously hosted only Middle Palaeolithic cultures suggests a real colonization event. There is no clearly dated archaeological source for the Aurignacian tool styles outside Europe from earlier than 47,000 years ago, but the Near East is a strong candidate. Belgian archaeologist Marcel Otte has suggested the Zagros Mountains (part of the Fertile Crescent) as a core homeland for the Aurignacian stone-crafting techniques, which is consistent with my view of the Fertile Crescent as a Palaeolithic corridor into the Levant. The route of entry of the first modern humans into Europe was most likely via the Bosporus (which at that time was dry, with the Black Sea a freshwater lake).
³

Matching genes to the dates on the stones

The tantalizing question is whether there are any genetic traces of this first entry into Europe. Astoundingly, there is in fact just one single mitochondrial line that has anything like that antiquity in Europe, and ‘she’ has an ancestor in the Near East. In other words, there is a fit, and most likely indicates that Europe was initially colonized by a single group. This insight does not come from opening a ‘genetic history book’ and looking for the right gene line with the right date – such books do not exist.
⁴
The tangled genetic prehistory of Europe is only just beginning to be teased apart. For a start, in the past 50,000 years Europe has seen multiple population movements and suffered massive extinctions in the ice age. Wars, invasions, and later migrations to and fro between Europe and the
Near East may have churned the human melting pot on several occasions.

A major international team of thirty-seven collaborators, headed by evolutionary geneticist Martin Richards, now of Huddersfield University, England, collected all available mtDNA data and recently showed us how it can be done. They reviewed nearly all existing prehistoric mitochondrial research on Europe, and using a carefully crafted set of rules to detect and eliminate errors, such as effects of back-migration, they identified eleven founder lines in Europe and eighteen potential source lines in the Near East.
⁵

Using the genetic clock, Richards and his colleagues dated both the source lines in the Near East and the founder lines in Europe (
Figure 3.2
). Four of the source lines (J, T, U5, and I in the figure) in the Levant could be dated to between 45,000 and 55,000 years ago, suggesting that the Near East had itself been colonized around that time by lines that were daughters and granddaughters of Nasreen. As can be seen from
Figure 3.3
, these were of course great-granddaughter and granddaughter lines from L3, our single Out-of-Africa Eve. Given the quite wide error margins for mtDNA dates, 45,000–55,000 years ago still brackets the earliest Upper Palaeolithic dates, so the time of the colonization of the Near East seems to fit.
⁶

The fifth daughter of Europa

Perhaps the most stunning conclusion of many reached in this comprehensive review of European maternal genetic prehistory is the identification and dating of Europe’s first founder line, U5. Initially it was only U5, a genetic great-granddaughter of one of the four main Levantine founders, who moved into Europe (
Figure 3.4
). The Europa clan is characteristic of the Near East and Europe. In spite of its antiquity, it is not found in East Asia, being confined to the Levant and the Gulf, western Central Asia, countries round the Mediterranean, and Europe, with an ancient daughter branch, U2i, in
India. The clan as a whole has an antiquity of over 50,000 years in the Near East. According to the molecular clock, our fifth daughter of Europa, U5, also dates back 50,000 years and represents by far the earliest line to enter Europe, 15,000 years before the next European founder line. But how is it that Europa’s genetic signal spread to the Near East and, through her daughter U5, on to Europe, from 54,400 to 50,000 years ago, when the archaeological dates for the Upper Palaeolithic first appearing in the Levant, and then the earliest Aurignacian in Bulgaria, are respectively only 47,100 and 46,000 years? This difference can be explained by a systematic under-recording of radiocarbon dates for any age over 40,000 years, giving a ceiling effect.
⁷

Figure 3.2
   Estimated dates of intrusion (95% confidence range) of modern human mtDNA lines into Europe from the Near East, using founder analysis.
⁵
The earliest line is from Europa (U5), corresponding with the Earliest Upper Palaeolithic in Europe, followed by ‘HV’ corresponding with the Early Upper Palaeolithic, and ‘I’ corresponding with the Middle Upper Palaeolithic.
¹

Figure 3.3
   The West Eurasian mtDNA tree. As can be seen, Manju does not feature and, although Nasreen and Rohani date to between 65–70,000 years, expansion of West Eurasian lines only occurs after 55,000 years ago, corresponding with north-west movement from South Asia. Links with India
¹⁰
, North Africa
⁹
and America (see
Chapter 7
⁴⁷
) in paler shade. Dating based on complete mtDNA sequence analysis (see
Chapter 1
²²
).

Although U5 apparently had her origins in the Near East at roughly the same time as her entry into Europe, her descendants are found there now only in a restricted area in minorities living mainly in Turkey and the Trans-Caucasus region of Turkey and Iran (see
Figure 3.4
). These minorities include the Turks, Armenians, Azerbaijanis, and Kurds, all of whom still live within the ancient limits of the Fertile Crescent that stretches from Turkey and the Trans-Caucasus south-east along the Zagros Mountains through Iraq and Iran. The Fertile Crescent co-extends with Kurdistan, finally forming a corridor parallel to but north of Mesopotamia, running towards the coast of the Arabian Gulf and thus linking the Levant with the Indian Ocean. Significantly, U5 is almost absent from Arabia, apparently denying those peoples’ ancestors as the primary source population for the first Aurignacian colonization of Europe.

Figure 3.4
   Suggested routes of spread of gene lines into Europe. Grey line corresponds with the Earliest Upper Palaeolithic, remaining concentrated round the Mediterranean (
Figure 3.1
), black line with the later ‘Early Upper Palaeolithic’ entering from Eastern Europe and found more in north and western Europe.
^{3,5,8,14–19,28–37}
(Y-chromosome lines are in italic – less securely dated than mtDNA.
²⁹
)

Do we have any genetic trail that exactly fits the rapid movement of the Aurignacian tool-makers, westward within central Europe, taking them to the Pyrenees and Spain by 40,000 years ago? Although U5 is now ubiquitous in Europe, we do know that the oldest Europa great-granddaughter, U5a, dating from around 40,000 years ago, is commonest in the Basque country of northern Spain. One of the only European refuges during the last ice age, the Basque region managed to preserve more of its original genetic diversity than did other parts of Western Europe.

U5 is thus the one surviving Europa daughter line that identifies the first European ancestors up to 50,000 years ago, and is an ancestral type shared with Armenians, Turks, Azeris, and Kurds. What do we know of her family, where did she come from, and who were her sisters? Inspection of the gene-line tree (see
Figure 3.3
) gives us a genealogy that we can recount in biblical style: Europa was genetic daughter of Rohani, who was genetic daughter of Nasreen, who was the genetic daughter of the out-of-Africa L3. By what route, however, did the Europa maternal clan arrive in the Levant, and where was her daughter U5, who colonized Europe, born? Both the Nasreen and Rohani root types are unknown except in South Asia, where Nasreen root types are found at low rates and Rohani is found in great variety. Most Rohani types in India are
found nowhere else, and the great diversity of Rohani in India allows us to estimate when her line began to expand. This was at least 55,000 years ago, thus predating the arrival of Rohani’s daughter Europa in the Levant and making a strong case for South Asia as the ultimate ancestral home of European lines. Even this expansion date is likely to be an underestimate of the age of the Rohani clan. Rohani may well be older than 55,000 years in Asia: much older estimates of the ages of two Asian subgroups of Rohani have been obtained in China.
⁸

The first three of the seven Europa daughters were all 50,000 years old

The fifth genetic daughter of the Europa clan did have other sisters: there were seven Europa daughters, but only two of them were anything like the same age as U5. These were U6 and U2i, and neither was characteristic of Europeans. We have already come across U6 in North Africa. A unique identifier of Berbers, she has the same age as U5, 50,000 years, suggesting that as U5 moved north-west out of Turkey into Europe, U6 moved west round the southern shore of the Mediterranean to North Africa. We even have possible physical evidence of those North African pioneers arriving from the Levant. Early Upper Palaeolithic tools have been found at the Libyan coastal site of Haua Fteah probably starting from 40,000 years ago, and possibly reflecting this early invasion.
⁹

The third of the Europa clan’s three 50,000-year-old genetic daughters seems to have been born a quarter of the globe away from the Berbers of Libya, somewhere along the coast of the Indian Ocean. Accounting for 9.5 per cent of all Indian maternal lines and a massive 78 per cent of all Indian Europa lines, U2i is clearly home-grown in that region, with an age of 53,000 years in India. U2i is absent from the Levant and Europe, where we find a small European branch version, U2e, at half to two-thirds of her age.
¹⁰
(See
Figure 3.3
.)