Sorry for the last weeks of silence, I have been rather busy lately. I am having more projects going on, and (because of that) I also wanted to finish a project I have been working on for many months already.
I have therefore decided to publish a provisional version of the text, in the hope that it will be useful in the following months, when I won’t be able to update it as often as I would like to:
EDIT (20 JAN 2019): For those of you who are more comfortable reading in your native language, I have placed some links to automatic translations by Google Translate. They might work especially well for the texts of A Game of Clans & A Clash of Chiefs.
Don’t forget to check out the maps included in the supplementary materials: I have added Y-DNA, mtDNA, and ADMIXTURE data using GIS software. The PCA graphics are also important to follow the main text.
NOTE. Right now the files are only in my server. I will try to upload them to Academia.edu and Research Gate when I have time, I have uploaded them to Academia.edu and ResearchGate, in case the websites are too slow.
I would have preferred to wait for a thorough revision of the section on archaeology and the linguistic sections on Uralic, but I doubt I will have time when the reviews come, so it was either now or maybe next December…
I say so in the introduction, but it is evident that certain aspects of the book are tentative to say the least: the farther back we go from Late Proto-Indo-European, the less clear are many aspects. Also, linguistically I am not convinced about Eurasiatic or Nostratic, although they do have a certain interest when we try to offer a comprehensive view of the past, including ethnolinguistic identities.
I cannot be an expert in everything, and these books cover a lot. I am bound to publish many corrections as new information appears and more reviews are sent. For example, just days ago (before SNP calls of Wang et al. 2018 were published) some paragraphs implied that AME might have expanded Nostratic from the Middle East. Now it does not seem so, and I changed them just before uploading the text. That’s how tentative certain routes are, and how much all of this may change. And that only if we accept a Nostratic phylum…
NOTE. Since the first book I wrote was the linguistic one, and I have spent the last months updating the archaeology + genetics part, now many of you will probably understand 1) why I am so convinced about certain language relationships and 2) how I used many posts to clarify certain ideas and receive comments. Many posts offer probably a good timeline of what I worked with, and when.
I did not add this section to the books, because they are still not ready for print, but I think this is due somewhere now. It is impossible to reference all who have directly or indirectly contributed to this, so this is a list of those I feel have played an important role.
I am indebted to the following people (which does not mean that they share my views, obviously):
First and foremost, to Fernando López-Menchero, for having the patience to review with detail many parts on Indo-European linguistics, knowing that I won’t accept many of his comments anyway. The additional information he offers is invaluable, but I didn’t want to turn this into a huge linguistic encyclopaedia with unending discussions of tiny details of each reconstructed word. I think it is already too big as it is.
I would not have thought about doing this if it were not for the interest of Wekwos (Xavier Delamarre) in publishing a full book about the Indo-European demic diffusion model (in the second half of 2017, I think). It was them who suggested that I extended the content, when all I had done until then was write an essay and draw some maps in my free time between depositing the PhD thesis and defending it.
Sadly, as much as I would like to publish a book with a professional publisher, I don’t think ancient DNA lends itself for the traditional format, so my requests (mainly to have free licenses and being able to review the text at will, as new genetic papers are published) were logically not acceptable. Also, the main aim of all volumes, especially the linguistic one, is the teaching of essentials of Late Proto-Indo-European and related languages, and this objective would be thwarted by selling each volume for $50-70 and only in printed format. I prefer a wider distribution.
At first I didn’t think much of this proposal, because I do not benefit from this kind of publications in my scientific field, but with time my interest in writing a whole, comprehensive book on the subject grew to the point where it was already an ongoing project, probably by the start of 2018.
I would not have been in contact with Wekwos if it were not for user Camulogène Rix at Anthrogenica, so thanks for that and for the interest in this work.
I would not have thought of writing this either if not for the spontaneous support (with an unexpected phone call!) of a professor of the Complutense University of Madrid, Ángel Gómez Moreno, who is interested in this subject – as is his wife, a professor of Classics more closely associated to Indo-European studies, and who helped me with a search for Indo-Europeanists.
EDIT (1 JAN 2019): I remembered that Karin Bojs sent me her book after reading the demic diffusion model. I may have also thought about writing a whole book back then, but mid-2017 is probably too early for the project.
Professor Kortlandt is still to review the text, but he contributed to both previous essays in some very interesting ways, so I hope he can help me improve the parts on Uralic, and maybe alternative accounts of expansion for Balto-Slavic, depending on the time depth that he would consider warranted according to the Temematic hypothesis.
The maps are evidently (for those who are interested in genetics) in part the result of the effort of the late Jean Manco: As you can see from the maps including Y-DNA and mtDNA samples, I have benefitted from her way of organising data and publishing it. Similarly, the work of Iain McDonald in assessing the potential migration routes of R1b and R1a in Europe with the help of detailed maps was behind my idea for the first maps, and consequently behind these, too.
Readers of this blog with interesting comments have also been essential for the improvement of the texts. You can probably see some of your many contributions there. I may not answer many comments, because I am always busy (and sometimes I just don’t have anything interesting to say), but I try to read all of them.
Users of other sites, like Anthrogenica, whose particular points of view and deep knowledge of some very specific aspects are sometimes very useful. In particular, user Anglesqueville helped me to fix some issues with the merging of datasets to obtain the PCAs and ADMIXTURE, and prepared some individual samples to merge them.
Even without posting anything, Google Analytics keeps sending me messages about increasing user fidelity (returning users), and stats haven’t really changed (which probably means more people are reading old posts), so thank you for that.
The Sahara was wetter and greener during multiple interglacial periods of the Quaternary, when some have suggested it featured very large (mega) lakes, ranging in surface area from 30,000 to 350,000 km2. In this paper, we review the physical and biological evidence for these large lakes, especially during the African Humid Period (AHP) 11–5 ka. Megalake systems from around the world provide a checklist of diagnostic features, such as multiple well-defined shoreline benches, wave-rounded beach gravels where coarse material is present, landscape smoothing by lacustrine sediment, large-scale deltaic deposits, and in places, tufas encrusting shorelines. Our survey reveals no clear evidence of these features in the Sahara, except in the Chad basin. Hydrologic modeling of the proposed megalakes requires mean annual rainfall ≥1.2 m/yr and a northward displacement of tropical rainfall belts by ≥1000 km. Such a profound displacement is not supported by other paleo-climate proxies and comprehensive climate models, challenging the existence of megalakes in the Sahara. Rather than megalakes, isolated wetlands and small lakes are more consistent with the Sahelo-Sudanian paleoenvironment that prevailed in the Sahara during the AHP. A pale-green and discontinuously wet Sahara is the likelier context for human migrations out of Africa during the late Quaternary.
The whole review is an interesting read, but here are some relevant excerpts:
Various researchers have suggested that megalakes coevally covered portions of the Sahara during the AHP and previous periods, such as paleolakes Chad, Darfur, Fezzan, Ahnet-Mouydir, and Chotts (Fig. 2, Table 2). These proposed paleolakes range in size by an order of magnitude in surface area from the Caspian Sea–scale paleo-Lake Chad at 350,000 km2 to Lake Chotts at 30,000 km2. At their maximum, megalakes would have covered ~ 10% of the central and western Sahara, similar to the coverage by megalakes Victoria, Malawi, and Tanganyika in the equatorial tropics of the African Rift today. This observation alone should raise questions of the existence of megalakes in the Sahara, and especially if they developed coevally. Megalakes, because of their significant depth and area, generate large waves that become powerful modifiers of the land surface and leave conspicuous and extensive traces in the geologic record.
Lakes, megalakes, and wetlands
Active ground-water discharge systems abound in the Sahara today, although they were much more widespread in the AHP. They range from isolated springs and wet ground in many oases scattered across the Sahara (e.g., Haynes et al., 1989) to wetlands and small lakes (Kröpelin et al., 2008). Ground water feeding these systems is dominated by fossil AHP-age and older water (e.g., Edmunds and Wright 1979; Sonntag et al., 1980), although recently recharged water (<50 yr) has been locally identified in Saharan ground water (e.g., Sultan et al., 2000; Maduapuchi et al., 2006).
In our view, Lake Chad is the only former megalake in the Sahara firmly documented by sedimentologic and geomorphic evidence. Mega-Lake Chad is thought to have covered ~ 345,000 km2, stretching for nearly 8° (10–18°N) of latitude (Ghienne et al., 2002) (Fig. 2). The presence of paleo- Lake Chad was at one point challenged, but several—and in our view very robust—lines of evidence have been presented to support its development during the AHP. These include: (1) clear paleo-shorelines at various elevations, visible on the ground (Abafoni et al., 2014) and in radar and satellite images (Schuster et al., 2005; Drake and Bristow, 2006; Bouchette et al., 2010); (2) sand spits and shoreline berms (Thiemeyer, 2000; Abafoni et al., 2014); and (3) evaporites and aquatic fauna such as fresh-water mollusks and diatoms in basin deposits (e.g., Servant, 1973; Servant and Servant, 1983). Age determinations for all but the Holocene history of mega- Lake Chad are sparse, but there is evidence for Mio-Pliocene lake (s) (Lebatard et al., 2010) and major expansion of paleo- Lake Chad during the AHP (LeBlanc et al., 2006; Schuster et al., 2005; Abafoni et al., 2014; summarized in Armitage et al., 2015) up to the basin overflow level at ~ 329m asl.
Insights from hydrologic mass balance of megalakes
Using these conservative conditions (i.e., erring in the direction that will support megalake formation), our hydrologic models for the two biggest central Saharan megalakes (Darfur and Fezzan) require minimum annual average rainfall amounts of ~ 1.1 m/yr to balance moisture losses from their respective basins (Supplementary Table S1). Lake Chad required a similar amount (~1 m/yr; Supplementary Table S1) during the AHP according to our calculations, but this is plausible, because even today the southern third of the Chad basin receives ≥1.2 m/yr (Fig. 2) and experiences a climate similar to Lake Victoria. A modest 5° shift in the rainfall belt would bring this moist zone northward to cover a much larger portion of the Chad basin, which spans N13° ±7°. Estimated rainfall rates for Darfur and Fezzan are slightly less than the average of ~ 1.3 m/yr for the Lake Victoria basin, because of the lower aw values, that is, smaller areas of Saharan megalakes compared with their respective drainage basins (Fig. 15).
Estimates of paleo-rainfall during the AHP
Here major contradictions develop between the model outcomes and paleo-vegetation evidence, because our Sahelo-Sudanian hydrologic model predicts wetter conditions and therefore more tropical vegetation assemblages than found around Lake Victoria today. In fact, none of the very wet rainfall scenarios required by all our model runs can be reconciled with the relatively dry conditions implied by the fossil plant and animal evidence. In short, megalakes cannot be produced in Sahelo-Sudanian conditions past or present; to form, they require a tropical or subtropical setting, and major displacements of the African monsoon or extra-desert moisture sources.
If not megalakes, what size lakes, marshes, discharging springs, and flowing rivers in the Sahara were sustainable in Sahelo-Sudanian climatic conditions? For lakes and perennial rivers to be created and sustained, net rainfall in the basin has to exceed loss to evapotranspiration, evaporation, and infiltration, yielding runoff that then supplies a local lake or river. Our hydrologic models (see Supplementary Material) and empirical observations (Gash et al., 1991; Monteith, 1991) for the Sahel suggest that this limit is in the 200–300 mm/yr range, meaning that most of the Sahara during the AHP was probably too dry to support very large lakes or perennial rivers by means of local runoff. This does not preclude creation of local wetlands supplied by ground-water recharge focused from a very large recharge area or forced to the surface by hydrologic barriers such as faults, nor megalakes like Chad supplied by moisture from the subtropics and tropics outside the Sahel. But it does raise a key question concerning the size of paleolakes, if not megalakes, in the Sahara during the AHP. Our analysis suggests that Sahelo-Sudanian climate could perhaps support a paleolake approximately ≤5000 km2 in area in the Darfur basin and ≤10,000–20,000 km2 in the Fezzan basin. These are more than an order of magnitude smaller than the megalakes envisioned for these basins, but they are still sizable, and if enclosed in a single body of water, should have been large enough to generate clear shorelines (Enzel et al., 2015, 2017). On the other hand, if surface water was dispersed across a series of shallow and extensive but partly disconnected wetlands, as also implied by previous research (e.g., Pachur and Hoelzmann, 1991), then shorelines may not have developed.
One of the underdeveloped ideas of my Indo-European demic diffusion model was that R1b-V88 had migrated through South Italy to Northern Africa, and from it using the Sahara Green Corridor to the south, from where the “upside-down” view of Bender (2007) could have occurred, i.e. Afroasiatic expanding westwards within the Green Sahara, precisely at this time, and from a homeland near the Megalake Chad region (see here).
Whether or not R1b-V88 brought the ‘original’ lineage that expanded Afroasiatic languages may be contended, but after D’Atanasio et al. (2018) it seems that only two lineages, E-M2 and R1b-V88, fit the ‘star-like’ structure suggesting an appropriate haplogroup expansion and necessary regional distribution that could explain the spread of Afroasiatic languages within a reasonable time frame.
This review shows that the hypothesized Green Sahara corridor full of megalakes that some proposed had fully connected Africa from west to east was actually a strip of Sahelo-Sudanian steppe spread to the north of its current distribution, including the Chad megalake, East Africa and Arabia, apart from other discontinuous local wetlands further to the north in Africa. This greenish belt would have probably allowed for the initial spread of early Afroasiatic proto-languages only through the southern part of the current Sahara Desert. This and the R1b-V88 haplogroup distribution in Central and North Africa (with a prevalence among Chadic speakers probably due to later bottlenecks), and the Near East, leaves still fewer possibilities for an expansion of Afroasiatic from anywhere else.
If my proposal turns out to be correct, this Afroasiatic-like language would be the one suggested by some in the vocabulary of Old European and North European local groups (viz. Kroonen for the Agricultural Substrate Hypothesis), and not Anatolian farmer ancestry or haplogroup G2, which would have been rather confined to Southern Europe, mainly south of the Loess line, where incoming Middle East farmers encountered the main difficulties spreading agriculture and herding, and where they eventually admixed with local hunter-gatherers.
NOTE. If related to attested languages before the Roman expansion, Tyrsenian would be a good candidate for a descendant of the language of Anatolian farmers, given the more recent expansion of Anatolian ancestry to the Tuscan region (even if already influenced by Iran farmer ancestry), which reinforces its direct connection to the Aegean.
The fiercest opposition to this R1b-V88 – Afroasiatic connection may come from:
Traditional Hamito-Semitic scholars, who try to look for any parent language almost invariably in or around the Near East – the typical “here it was first attested, ergo here must be the origin, too”-assumption (coupled with the cradle of civilization memes) akin to the original reasons behind Anatolian or Out-of-India hypotheses; and of course
autochthonous continuity theories based on modern subclades, of (mainly Semitic) peoples of haplogroup E or J, who will root for either one or the other as the Afroasiatic source no matter what. As we have seen with the R1a – Indo-European hypothesis (see here for its history), this is never the right way to look at prehistoric migrations, though.
I proposed that it was R1a-M417 the lineage marking an expansion of Indo-Uralic from the east near Lake Baikal, then obviously connected to Yukaghir and Altaic languages marked by R1a-M17, and that haplogroup R could then be the source of a hypothetic Nostratic expansion (where R2 could mark the Dravidian expansion), with upper clades being maybe responsible for Borean.
However, recent studies have shown early expansions of R1b-297 to East Europe (Mathieson et al. 2017 & 2018), and of R1b-M73 to East Eurasia probably up to Siberia, and possibly reaching the Pacific (Jeong et al. 2018). Also, the Steppe Eneolithic and Caucasus Eneolithic clusters seen in Wang et al. (2018) would be able to explain the WHG – EHG – ANE ancestry cline seen in Mesolithic and Neolithic Eurasia without a need for westward migrations.
Dravidian is now after Narasimhan et al. (2018) and Damgaard et al. (Science 2018) more and more likely to be linked to the expansion of the Indus Valley civilization and haplogroup J, in turn strongly linked to Iranian farmer ancestry, thus giving support to an Elamo-Dravidian group stemming from Iran Neolithic.
NOTE. This Dravidian-IVC and Iran connection has been supported for years by knowledgeable bloggers and commenters alike, see e.g. one of Razib Khan’s posts on the subject. This rather early support for what is obvious today is probably behind the reactionary views by some nationalist Hindus, who probably saw in this a potential reason for a strengthened Indo-Aryan/Dravidian divide adding to the religious patchwork that is modern India.
I am not in a good position to judge Nostratic, and I don’t think Glottochronology, Swadesh lists, or any statistical methods applied to a bunch of words are of any use, here or anywhere. The work of pioneers like Illich-Svitych or Starostin, on the other hand, seem to me solid attempts to obtain a faithful reconstruction, if rather outdated today.
NOTE. I am still struggling to learn more about Uralic and Indo-Uralic; not because it is more difficult than Indo-European, but because – in comparison to PIE comparative grammar – material about them is scarce, and the few available sources are sometimes contradictory. My knowledge of Afroasiatic is limited to Semitic (Arabic and Akkadian), and the field is not much more developed here than for Uralic…
If one wanted to support a Nostratic proto-language, though, and not being able to take into account genome-wide autosomal admixture, the only haplogroup right now which can connect the expansion of all its branches is R1b-M343:
R1b-L278 expanded from Asia to Europe through the Iranian Plateau, since early subclades are found in Iran and the Caucasus region, thus supporting the separation of Elamo-Dravidian and Kartvelian branches;
R1b-V88 expanding everywhere in Europe, and especially the branch expanding to the south into Africa, may be linked to the initial Afroasiatic expansion through the Pale-Green Sahara corridor (and even a hypothetic expansion with E-M2 subclades and/or from the Middle East would also leave open the influence of V88 and previous R1b subclades from the Middle East in the emergence of the language);
R1b-297 subclades expanding to the east may be linked to Eurasiatic, giving rise to both Indo-Uralic (M269) and Macro- or Micro-Altaic (M73) expansions.
This is shameless, simplistic speculation, of course, but not more than the Nostratic hypothesis, and it has the main advantage of offering ‘small and late’ language expansions relative to other proposals spanning thousands (or even tens of thousands) of years more of language separation. On the other hand, that would leave Borean out of the question, unless the initial expansion of R1b subclades happened from a community close to lake Baikal (and Mal’ta) that was also at the origin of the other supposedly related Borean branches, whether linked to haplogroup R or to any other…
NOTE. If Afroasiatic and Indo-Uralic (or Eurasiatic) are not genetically related, my previous simplistic model, R1b-Afroasiatic vs. R1a-Eurasiatic, may still be supported, with R1a-M17 potentially marking the latest meaningful westward population expansion from which EHG ancestry might have developed (see here). Without detailed works on Nostratic comparative grammar and dialectalization, and especially without a lot more Palaeolithic and Mesolithic samples, all this will remain highly speculative, like proposals of the 2000s about Y-DNA-haplogroup – language relationships.
Insights from the Green Saharan Y-chromosomal findings (emphasis mine):
It is widely accepted that sub-Saharan Y chromosomes are dominated by E-M2 lineages carried by Bantu-speaking farmers as they expanded from West Africa starting < 5 kya, reaching South Africa within recent centuries . The E-M2-Bantu lineages lie phylogenetically within the E-M2-Green Sahara lineage and show at least three explosive lineage expansions beginning 4.9–5.3 kya  (Fig. 1a). These events of E-M2-Bantu expansion are slightly later than the R-V88 expansion, and highlight the range of male demographic changes in the mid-Holocene. North of the Sahara, in addition to the four trans-Saharan haplogroups, haplogroup E-M81 (which diverged from E-M78 ~ 13 kya) became very common in present-day populations as a result of another massive expansion ~ 2 kya  (Fig. 1a).
Although Y chromosomes exist within populations and so share and reflect the general history of those populations, they can sometimes show some departures from other parts of the genome that result from differences in male and female behaviors. D’Atanasio et al.  highlight one such contrast in their study. Present-day North African populations show substantial sub-Saharan autosomal and mtDNA genetic components ascribed to the Roman and Arab slave trades 1–2 kya , but carry few sub-Saharan Y lineages from this source, probably reflecting the smaller numbers of male slaves and their reduced reproductive opportunities when compared to those of female slaves. The sub-Saharan Y chromosomes in these North African populations thus originate predominantly from the earlier Green Sahara period.
In this part of Africa, the indigenous languages that are spoken belong to three of the four African linguistic families (Afro-Asiatic, Nilo-Saharan and Niger-Congo). Interestingly, these languages show non-random associations with Y lineages. For example, Chadic languages within the Afro-Asiatic family are associated with haplogroup R-V88, whereas Nilo-Saharan languages are associated with specific sublineages within A3-M13 and E-M78, further illustrating the complex human history of the region.
(…) what are the reasons for the very rapid R-V88 expansion 5–6 kya  and E-M81 expansion ~ 2 kya , and how do these expansions fit within general worldwide patterns of male-specific expansions, which in other cases have been linked to cultural and technological changes ?
I think that the only known haplogroup expansion that might fit today the spread and dialectalization of Afroasiatic, a proto-language probably contemporaneous or slighly older than Middle Proto-Indo-European, is that of R1b-V88 lineages. However, without ancient DNA samples to corroborate this, we cannot be sure.