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Brown eyed Neanderthals of Croatia

Since years ago, when one Neanderthal individual from Gibraltar was identified as having reddish hair color (but not via the Homo sapiens alleles but a different one of their own), some authors have idealized Neanderthals as hyper-white. For example the Gibraltar kid whose reconstruction is pictured at the right, whose skin looks unhealthily way too pale to be living in Andalusia (the Ice Age would not affect solar radiation in principle, only temperature).
Now other researchers have inferred that the Neanderthals from Vindija cave (Croatia) probably had brown eyes, hair and even skin, which is described as tawny, a light brown/orange shade.
The paper is widely discussed at a free article in Science magazine, titled: Were some Neanderthals blue eyed girls?, where the likes of Lalueza-Fox and John Hawks ponder the conclusions, rather critically. 
Of course, the conclusions are far from straightforward:


One complication is that traits such as hair color are controlled by multiple genes. To determine the cumulative impact of multiple genes on one trait, the authors assumed they could simply add together the impact of individual genes. The female Neandertal known as Vi33.26, for example, had seven genes for brown eyes, one for “not-brown” eyes, three for blue eyes, and four for “not-blue eyes.” By the researchers’ reckoning, that means a six-gene balance in favor of brown and a negative balance for blue, so Vi33.26’s eyes were probably brown. According to this method, all three Neandertals had a dark complexion and brown eyes, and although one was red-haired, two sported brown locks. 

They may well be right in regards to the eyes, although we really know way too little on human pigmentation as of now, never mind Neanderthal peculiarities, to be certain at all. In any case, considering that modern Europeans also display variety of eye and hair colors, I see no reason not to imagine that Neanderthals also had dark eyes and hair.

Those traits are after all non-adaptive or mostly so. Instead skin color is key for survival. So I am reluctant to accept tawny as a valid answer for skin color, at least in most of the shades suggested. Very few people if any have tawny skin color today at 45 degrees North, roughly the latitude of Vindija. And that is because of an adaptive reason: the human need to synthesize normally vitamin D using solar energy at the skin (it can also be ingested from fish mostly but it’s not as reliable in the long run).
Surely Neanderthals were also biological conditioned in that same way. Although now that I think of it I have never seen a paper stating it, just the same that I have never seen a paper that conclusively argues that Neanderthals lacked fur as we do, being our nearest cousins it is logical to think that they were a lot like ourselves. 
But regardless of the thornier issue of skin color, it’s probable that at least many Neanderthals had brown eyes and dark hair and also a less hyper-pale skin shade than often misrepresented. In this sense I welcome the news because painting Neanderthals as ultra-Nordics, when they lived largely in Southern Europe and even West Asia was really overdoing it towards the side of pseudoscience. 
 

Echoes from the Past (Oct 10)

A lot of stuff that I won’t probably dedicate more time nor space (sadly enough in some cases at least):

Middle Paleolithic:

Mass production of flint flakes at Palestinian Qassem Cave ··> Jerusalem Post, The Media Line, Ron Shimelmitz et al. at Journal of Human Evolution (PPV).


Upper Paleolihic:
Domestic dog with mammoth bone in mouth (left) found in Czech Republic (Gravettian context) ··> Pileta de Prehistoria[es], Discovery News, Journal of Archaeological Science (PPV). 
Australian rock art dated to c. 30 Ka ago in danger because of Rio Tinto mining activities at Burrup Peninsula ··> The Heritage Journal, The Guardian

Children made rock art in Rouffignac ··> The Heritage Journal.
Basque chasm captured sample of late UP animals. The “Kiputz IX trap” near Deba was a death sentence for 48 deer, 23 reindeer and 18 steppe bisons, none of which show any sign of human consumption. The best preserved skull is that of a male bison (right). The site is dated to c. 19-18 Ka ago, in the Solutrean period ··> Gara[es].

20,000 years ago Azrak (Jordan) was a fertile inhabited region and the first one to bury people in crouched position, it seems ··> MENA.

End of war allows dig to recover Paleolithic artifacts at Jaffna Peninsula (Ceylon) ··>  Sri Lanka News.

Neolithic & Metal Ages:

City older than Troy, dated to c. 7000 years ago, found not far away ··> National Turk, Hurriyet, Today’s Zaman.

Kurgan explored with tiny flying drone ··> Live Science.

Elevation reconstruction of the tomb
Girl’s tomb found near henge in Kent ··> The Heritage Journal.

Project to dig islands around Britain to establish origins of Neolithic ··> PhysOrg, Irish Weather Online
Iruña-Veleia: map shows there were two Veleias. Veleia Gori [VIIL(II)I(A) GORI] and Veleia Nova [VIILIII NOVVA.]are mentioned in a stone map of the Basque-Roman town ··> Iruina[es] (also here).

The ‘map’ (click to expand)
I’d speculate that GORI (a word that also appears in other inscriptions) might be goiri (upwards and attested as surname modernly) it could be also goren(a) (of the high, or something like that). Previously it had been supposed to mean gorri (red) because it appeared along with other color names, who knows?

Conservation efforts for Göbekli Tepe ··> Popular Archaeology.

Uncertain period:

Heart-shaped Australian stone ring at Little River (Victoria) could be astronomical observatory ··> BBC.

Human genetics and biology:
Extremely pale people may not be getting enough sun without burning (and hence may benefit from extra fish in the diet or industrial supplements) ··> SD.  
Claim, based on mtDNA, that major population expansion in East Asia is pre-Neolithic ··> Hong-Xiang Zheng et al. at PLoS ONE (open access).


Figure 2. mtDNA Bayesian skyline plot showing the size trend of 4 East Eurasian populations.
Take with a pinch of salt, of course. 
CHB: Chinese Han from Beijing, CHS CH from South China, CHD: CH from Denver, USA, JPT: Japanese from Tokyo. Notice how, whatever the case, CHS have the softest curve, with almost no sudden expansion signatures. 

Proposal to estimate sex bias in gene flow ··> N. Osada at PLoS ONE (open access). 
Jomon Era ancient mtDNA of Hokkaido Japan (includes N9b, D4h2, G1b, and M7a) ··> Dienekes, Noboru Adachi et al. at Physical Anthropology (PPV).
Population genetics conference at Porto, Portugal, on November 23-25 ··> link.

Other science news:

Solar system once had fifth gas planet, but was expelled ··> PhysOrg

Can primordial black holes be the elusive dark matter ··> PhysOrg.

Magic mushrooms (Psylocybe sp.) can impact certain personalities for the better, while being trivial for others ··> Psychedelic Research, SD.

2011 IgNobel prizes:

  • Physiology: no contagious yawning for turtles.
  • Chemistry: wasabi (pungent radish) fire alarm for heavy sleepers.
  • Medicine: people make better and worse decisions when under pressure to go to the loo.
  • Psychology: why do we sigh?
  • Biology: beetles love beer bottles.
  • Physics: why discus throwers get dizzy (and hammer ones do not)?
  • Mathematics: to a long list of doomsayers who predicted the end of the World… and failed.
  • Peace: smashing wrongly parked luxury cars with tanks in Vlinus, Lithuania.
  • Safety: driving while a visor intermittently blocks your sight.

Can neutrinos be faster than light? ··> Nature.

Gonorrhoea becoming resistant to antibiotics ··> BBC.

Special thanks to (see also): Stone Pages’ Archaeo News.

 

Lack of vitamin D also causes allergies among children

In another example of the critical role that vitamin D plays in human development, it has been demonstrated now that children with low levels of this key nutrient develop allergies.
Vitamin D is relatively difficult to obtain from food (mostly fish) but we make it in our skin when irradiated by sunlight. Skin color variation is directly related to this necessity.
In the past lack of vitamin D in children (or their mothers) has been linked to rickets, incorrect brain development, autoimmune diseases and other immunity related problems. Allergies also fall within the problematic of inappropriate immunity and can well be considered autoimmune diseases, even if often mild and with very specific triggers.
Source: Science Daily.
See also:
 
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Posted by on February 26, 2011 in health, human evolution, pigmentation, vitamin D

 

Vitamin D helps prevent urinary track infections

Vitamin D is one of the most important underlying factors for human pigmentation. We humans need regular supplies of this vitamin, which is seldom found in diet (fish essentially) and therefore Nature has provided us with sort of a photosynthetic skin, which generates the essential nutrient thanks to the energy of the Sun.
That is why humans loss partly their tan as they migrated northwards, where ultra-violet radiation is scarce, at least in winter.
I have on occasion discussed at my old blog Leherensuge several newly found roles of this critical vitamin besides bone formation: brain development, immune system and cholesterol. I have also mentioned a reason for the dark skin dominant in tropical peoples besides sunburns and skin cancer (vitamin B9, folate).
Well, there is yet another reason for the critical importance of vitamin D in our metabolism and coloring, though maybe not too different from one of the above (immune system): an specific defense response has been linked to vitamin D levels:
Abstract
The urinary tract is frequently being exposed to potential pathogens and rapid defence mechanisms are therefore needed. Cathelicidin, a human antimicrobial peptide is expressed and secreted by bladder epithelial cells and protects the urinary tract from infection. Here we show that vitamin D can induce cathelicidin in the urinary bladder. We analyzed bladder tissue from postmenopausal women for expression of cathelicidin, before and after a three-month period of supplementation with 25-hydroxyvitamin D3 (25D3). Cell culture experiments were performed to elucidate the mechanisms for cathelicidin induction. We observed that, vitamin D per se did not up-regulate cathelicidin in serum or in bladder tissue of the women in this study. However, when the bladder biopsies were infected with uropathogenic E. coli (UPEC), a significant increase in cathelicidin expression was observed after 25D3 supplementation. This observation was confirmed in human bladder cell lines, even though here, cathelicidin induction occurred irrespectively of infection. Vitamin D treated bladder cells exerted an increased antibacterial effect against UPEC and colocalization to cathelicidin indicated the relevance of this peptide. In the light of the rapidly growing problem of resistance to common urinary tract antibiotics, we suggest that vitamin D may be a potential complement in the prevention of UTI.
 
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Posted by on December 14, 2010 in health, human evolution, pigmentation, vitamin D