The brown man with blue eyes

Venus of Willendorf (30,000 – 27,000 BP). Is that a special headdress … or peppercorn hair? (source: Matthias Kabel)

Europeans already had blue eyes while still hunter-gatherers. This is what we’ve learned after retrieving ancient DNA from two Mesolithic individuals, one from Luxembourg, dated to 8,000 years ago, and another from Spain, dated to 7,000 years ago (Dienekes, 2013; Lazaridis et al.,2013). These are late hunter-gatherers, so there is always the possibility of gene flow from early European farmers. Nonetheless, the time of origin now seems earlier for the palette of European eye colors and probably for the palette of European hair colors. How much earlier? Probably within the same time frame when European skin turned white: somewhere between 11,000 and 19,000 years ago according to Beleza et al. (2013) or between 7,600 and 19,200 years according to Canfield et al. (2014). Although different genes are responsible for eye, hair, and skin color, there was probably a single selection pressure that seems to have acted primarily on early European women (Frost, 2006; Frost, 2008).

Interestingly, although the Luxembourg man was blue-eyed, he also had brown skin. He lacked the ‘European’ alleles at all three genes involved in the whitening of European skin. Such a genotype is extremely rare today in unadmixed Europeans (Khan, 2014). Equally odd is the fact that this brown-skinned European lived long after (Beleza et al., 2013) or probably after (Canfield et al., 2014) the time period when European skin turned white. How could that be? Well, these estimates apply only to the ancestors of living Europeans. This individual may not have been so lucky.

When the last ice age ended some 10,000 years ago, it may be that only some European populations had acquired a fully ‘European’ phenotype, i.e., white skin, multi-hued eyes and hair, a more childlike face, and longer, straighter hair. This phenotype would have been most predominant on the former steppe-tundra of northern and eastern Europe. Moving outward from this region, one would have seen humans with more and more of the evolutionarily older traits, i.e., brown skin, uniformly brown eyes and black hair, a more robust face, and short, frizzy hair.

This older phenotype might have persisted well into the Holocene in peripheral and isolated parts of Europe.  As Fleure (1945) notes:

In a few places in Sweden, Britain, and France, people have been noticed who show characteristics of the skull and face that remind one of late-Paleolithic man: these people are usually darker, in hair and eyes, than their neighbors; sometimes they even have swarthy skins.

Even in Scandinavia, we find references in folklore and mythology to an ancient dark-skinned population. A Norse poem, the Rigsthula, describes how the god Rig created a class of thralls who were black-haired, swarthy, and flat-nosed (Jonassen, 1951). This theme comes up elsewhere in Old Norse literature (Karras, 1988).

This leads us to the debate over the discovery of so-called ‘Negroid’ skeletal remains in Europe. Clearly, these individuals were not African, but nor were they like present-day Europeans. They seem to represent an older phenotype that had already lost predominance by Holocene times. The skeletal evidence is reviewed by Boule and Vallois (1957, pp. pp. 291-292):

‘In Brittany, as well as in Switzerland and in the north of Italy, there lived in the Polished Stone period, in the Bronze Age and during the early Iron Age, a certain number of individuals who differed in certain characters from their contemporaries’, in particular in the dolichocephalic character of their skull, in possessing a prognathism that was sometimes extreme, and a large grooved nose. This is a matter of partial atavism which in certain cases, as in the Neolithic Breton skull from Conguel, may attain to complete atavism. Two Neolithic individuals from Chamblandes in Switzerland are Negroid not only as regards their skulls but also in the proportions of their limbs. Several Ligurian and Lombard tombs of the Metal Ages have also yielded evidences of a Negroid element.

Since the publication of Verneau’s memoir, discoveries of other Negroid skeletons in Neolithic levels in Illyria and the Balkans have been announced. The prehistoric statues, dating from the Copper Age, from Sultan Selo in Bulgaria are also thought to portray Negroids. In 1928 René Bailly found in one of the caverns of Moniat, near Dinant in Belgium, a human skeleton of whose age it is difficult to be certain, but which seems definitely prehistoric. It is remarkable for its Negroid characters, which give it a resemblance to the skeletons from both Grimaldi and Asselar.

It is not only in prehistoric times that the Grimaldi race seems to have made its influence felt. Verneau has been able to see, now in modern skulls and now in living subjects, in the Italian areas of Piedmont, Lombardy, Emilia, Tuscany, and the Rhone Valley, numerous characters of the old fossil race.

This older phenotype must have gradually disappeared as the newer phenotype spread outwards from the plains of northern and eastern Europe. Why did one replace the other? What sort of selective advantage did the newer phenotype confer? The reason probably had less to do with physical appearance and more to do with the mental toolkit that humans had developed on the steppe-tundra of the last ice age. These northern hunting peoples were pre-adapted to technological complexity and thus better able to exploit the opportunities of later cultural environments (Frost, 2010). Some of them, specifically the semi-sedentary hunter-fisher-gatherers around the North Sea and the Baltic, would become pre-adapted not only to technological complexity but also to social and economic complexity (Frost, 2013).

References 

Beleza, S., Murias dos Santos, A., McEvoy, B., Alves, I., Martinho, C., Cameron, E., Shriver, M.D., Parra E.J., and Rocha, J. (2013). The timing of pigmentation lightening in Europeans. Molecular Biology and Evolution, 30, 24-35.

http://mbe.oxfordjournals.org/content/30/1/24.short

Boule, M. and H.V. Vallois. (1957). Fossil Men. New York: Dryden Press. 

Canfield, V.A., A. Berg, S. Peckins, S.M. Wentzel, K.C. Ang, S. Oppenheimer, and K.C. Cheng. (2014). Molecular phylogeography of a human autosomal skin color locus under natural selection, G3, 3, 2059-2067.

http://www.g3journal.org/content/3/11/2059.full 

Dienekes (2013).  Mesolithic Iberians (La Braña-Arintero) not ancestors of modern ones,

Dienekes’ Anthropology Blog
http://dienekes.blogspot.ca/2013/12/europeans-neolithic-farmers-mesolithic.html

Fleure, H.J. (1945). The distribution of types of skin color, Geographical Review, 35, 580-595. 

Frost, P. (2013). Origins of Northwest European guilt culture. Part II, Evo and Proud, December 14

http://evoandproud.blogspot.ca/2013/12/origins-of-northwest-european-guilt.html

Frost, P. (2010). Out of North Eurasia, Evo and Proud, May 27

http://evoandproud.blogspot.ca/2010/05/out-of-north-eurasia.html 

Frost, P. (2008). Sexual selection and human geographic variation, Special Issue: Proceedings of the 2nd Annual Meeting of the NorthEastern Evolutionary Psychology Society. Journal of Social, Evolutionary, and Cultural Psychology, 2(4), pp. 169-191.

http://www.jsecjournal.com/articles/volume2/issue4/NEEPSfrost.pdf

Frost, P. (2006). European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103.

Jonassen, C.T. (1951). Some historical and theoretical bases of racism in northwestern Europe, Social Forces, 30, 155-161.

Karras, R.M. (1988). Slavery and Society in Medieval Scandinavia. New Haven. 

Khan, R. (2014). Phenotypic Whiteness as an Outcome of Neolithic Admixture, The Unz Review: An Alternative Media Selection, January 3.

http://www.unz.com/gnxp/phenotypic-whiteness-as-an-outcome-of-neolithic-admixture/ 

Lazaridis, I., Patterson, N., Mittnik, A., Renaud, G., Mallick, S., et al. (2013). Ancient human genomes suggest three ancestral populations for present-day Europeans, BioRxiv, December 23.

http://biorxiv.org/content/early/2013/12/23/001552.full-text.pdf+html 

Archaic admixture in Africans

Expansion of modern humans out of Africa and within Africa. Mellars (2006).

When we discuss the origins of modern humans, the term ‘Out of Africa’ is a bit misleading. Our common ancestors came not from Africa as a whole but from a relatively small area somewhere in East Africa. Beginning around 80,000 years ago, this area was the scene of several population expansions that culminated in a ‘big bang’ c. 60,000 BP (Watson et al., 1997). This was a sustained expansion that pushed out of Africa and into Europe, Asia, Oceania, and the Americas.

These modern humans spread at the expense of more archaic ‘hominins’: Neanderthals in Europe and West Asia, and other poorly known groups elsewhere. But the latter were not totally replaced, as seen in the 1 to 4% Neanderthal admixture of present-day Europeans, East Asians, and Papuans. This has led some people to quip that only Africans are pure Homo sapiens:

Better yet, and a blow to Caucasian and Asian racists, the comparison of the human and Neanderthal genome makes it clear that it is only Africans who are 100 percent Homo sapiens, while in European (including American and Australian settlers) and Asian populations one can find up to 4 percent DNA stemming from the archaic and often maligned Neanderthal species - a hominid that went extinct more than 20,000 years ago. (Camphausen, 2010)

Well, no. Sub-Saharan Africans actually have more archaic admixture. The difference is that it came not from Neanderthals but from archaic groups within Africa. About 13% of the sub-Saharan gene pool comes from an earlier expansion of pre-modern hominins that occurred c. 111,000 years ago and seems to correspond to the entry of Skhul-Qafzeh hominins into the Middle East (Watson et al., 1997). This higher level of admixture may have come about because archaic Africans were behaviorally and physically closer to modern humans than the Neanderthals were.

Nonetheless, these ‘Paleoafricans’ were clearly archaic. They lacked something that modern humans had. What was this disadvantage that ultimately removed them from the struggle for existence? The answer is much debated, but most authors posit a limited capacity for symbolic thinking and social organization:

[…] the African exodus was predated by a cultural revolution involving new stone blade technologies, skin working tools, ornaments and imported red ochre […] More advanced symbolic systems in language and religious beliefs could have provided a competitive advantage to a group by promoting coordination and cohesion. (Atkinson et al., 2009)

Thus, when we discuss human origins, the real split was not between Africans and non-Africans but rather between two groups of Africans: archaics and moderns. Dienekes (2005) uses the terms ‘Paleoafricans’ and ‘Afrasians’:

It is common to distinguish between Africans and non-Africans, with the former being much more genetically diverse than the latter. But, the real "gap" in human origins seems to be between the really old Africans ("Paleoafricans") and the rest ("Afrasians").

The Paleoafrican element is entirely confined to Africa, while the Afrasian one is found in both Africa and Eurasia. Indeed, modern humans can be entirely split into two groups: (i) a group of "pure" Afrasians which includes all non-Africans, and (ii) a group of Afrasian-Paleoafricans which includes all non-Caucasoid Africans. Human groups of entirely Paleoafrican origin, unhybridized with the younger Afrasians are no longer in existence.

All of this leads to an intriguing conclusion. Since present-day sub-Saharan Africans were used as a benchmark to estimate Neanderthal admixture in present-day Eurasians, and since Paleoafrican gene sequences should be less ‘derived’ and more similar to Neanderthal gene sequences, Neanderthal admixture in present-day Eurasians is probably a bit higher than the estimated 1 to 4%.

References

Atkinson, Q.D., R.D. Gray, and A.J. Drummond. (2009). Bayesian coalescent inference of major human mitochondrial DNA haplogroup expansions in Africa, Proceedings of the Royal Society B, 276, 367–373

Camphausen, R.C. (2010). Evidence for interbreeding with Neanderthals, only Africans pure, Digital Journal, May 10, 2010,
http://www.digitaljournal.com/article/291798

Dienekes. (2005). The mitochondrial time depth of humanity, Dienekes’ Anthropology Blog, May 14, 2005.
http://dienekes.blogspot.com/2005/05/mitochondrial-time-depth-of-humanity.html

Mellars, P. (2006). Why did modern human populations disperse from Africa ca. 60,000 years ago? A new model, Proceedings of the National Academy of Sciences (USA), 103, 9381-9386.
http://www.pnas.org/content/103/25/9381.abstract

Watson, E., P. Forster, M. Richards, and H-J. Bandelt. (1997). Mitochondrial footprints of human expansions in Africa, American Journal of Human Genetics, 61, 691-704.