Category Archives: ‘White’ people

Aryans – native after all?

(based mainly on Jagat K. Motwani’s None But India [Bharat]: The Cradle of Aryans, Sanskrit, Vedas, & Swastika – ISBN 9781450261272)

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In Western academia the story goes like this: Continue reading Aryans – native after all?

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Cheddar Man: DNA shows early Briton had dark skin

(Reposted from: https://www.bbc.co.uk/news/amp/science-environment-42939192)

Cheddar Man: DNA shows early Briton had dark skin

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DNA shows early Brit had dark skin
Image caption DNA shows early Brit had dark skin

A cutting-edge scientific analysis shows that a Briton from 10,000 years ago had dark brown skin and blue eyes.

Researchers from London’s Natural History Museum extracted DNA from Cheddar Man, Britain’s oldest complete skeleton, which was discovered in 1903.

University College London researchers then used the subsequent genome analysis for a facial reconstruction.

It underlines the fact that the lighter skin characteristic of modern Europeans is a relatively recent phenomenon.

No prehistoric Briton of this age had previously had their genome analysed.

As such, the analysis provides valuable new insights into the first people to resettle Britain after the last Ice Age.

The analysis of Cheddar Man’s genome – the “blueprint” for a human, contained in the nuclei of our cells – will be published in a journal, and will also feature in the upcoming Channel 4 documentary The First Brit, Secrets Of The 10,000-year-old Man.

‘Cheddar George’ tweet on early Briton

Cheddar Man’s remains had been unearthed 115 years ago in Gough’s Cave, located in Somerset’s Cheddar Gorge. Subsequent examination has shown that the man was short by today’s standards – about 5ft 5in – and probably died in his early 20s.

Prof Chris Stringer, the museum’s research leader in human origins, said: “I’ve been studying the skeleton of Cheddar Man for about 40 years

“So to come face-to-face with what this guy could have looked like – and that striking combination of the hair, the face, the eye colour and that dark skin: something a few years ago we couldn’t have imagined and yet that’s what the scientific data show.”

Cheddar Man
Image captionA replica of Cheddar Man’s skeleton now lies in Gough’s Cave

Fractures on the surface of the skull suggest he may even have met his demise in a violent manner. It’s not known how he came to lie in the cave, but it’s possible he was placed there by others in his tribe.

The Natural History Museum researchers extracted the DNA from part of the skull near the ear known as the petrous. At first, project scientists Prof Ian Barnes and Dr Selina Brace weren’t sure if they’d get any DNA at all from the remains.

But they were in luck: not only was DNA preserved, but Cheddar Man has since yielded the highest coverage (a measure of the sequencing accuracy) for a genome from this period of European prehistory – known as the Mesolithic, or Middle Stone Age.

They teamed up with researchers at University College London (UCL) to analyse the results, including gene variants associated with hair, eye and skin colour.

Extra mature Cheddar

They found the Stone Age Briton had dark hair – with a small probability that it was curlier than average – blue eyes and skin that was probably dark brown or black in tone.

This combination might appear striking to us today, but it was a common appearance in western Europe during this period.

Steven Clarke, director of the Channel Four documentary, said: “I think we all know we live in times where we are unusually preoccupied with skin pigmentation.”

Prof Mark Thomas, a geneticist from UCL, said: “It becomes a part of our understanding, I think that would be a much, much better thing. I think it would be good if people lodge it in their heads, and it becomes a little part of their knowledge.”

Unsurprisingly, the findings have generated lots of interest on social media.

Cheddar Man’s genome reveals he was closely related to other Mesolithic individuals – so-called Western Hunter-Gatherers – who have been analysed from Spain, Luxembourg and Hungary.

Dutch artists Alfons and Adrie Kennis, specialists in palaeontological model-making, took the genetic findings and combined them with physical measurements from scans of the skull. The result was a strikingly lifelike reconstruction of a face from our distant past.

Pale skin probably arrived in Britain with a migration of people from the Middle East around 6,000 years ago. This population had pale skin and brown eyes and absorbed populations like the ones Cheddar Man belonged to.

Chris Stringer
Image caption Prof Chris Stringer had studied Cheddar Man for 40 years – but was struck by the Kennis brothers’ reconstruction

No-one’s entirely sure why pale skin evolved in these farmers, but their cereal-based diet was probably deficient in Vitamin D. This would have required agriculturalists to absorb this essential nutrient from sunlight through their skin.

“There may be other factors that are causing lower skin pigmentation over time in the last 10,000 years. But that’s the big explanation that most scientists turn to,” said Prof Thomas.

Boom and bust

The genomic results also suggest Cheddar Man could not drink milk as an adult. This ability only spread much later, after the onset of the Bronze Age.

Present-day Europeans owe on average 10% of their ancestry to Mesolithic hunters like Cheddar Man.

Britain has been something of a boom-and-bust story for humans over the last million-or-so years. Modern humans were here as early as 40,000 years ago, but a period of extreme cold known as the Last Glacial Maximum drove them out some 10,000 years later.

There’s evidence from Gough’s Cave that hunter-gatherers ventured back around 15,000 years ago, establishing a temporary presence when the climate briefly improved. However, they were soon sent packing by another cold snap. Cut marks on the bones suggest these people cannibalised their dead – perhaps as part of ritual practices.

Image copyright CHANNEL 4Ian Barnes
Image caption The actual skull of Cheddar Man is kept in the Natural History Museum, seen being handled here by Ian Barnes

Britain was once again settled 11,000 years ago; and has been inhabited ever since. Cheddar Man was part of this wave of migrants, who walked across a landmass called Doggerland that, in those days, connected Britain to mainland Europe. This makes him the oldest known Briton with a direct connection to people living here today.

This is not the first attempt to analyse DNA from the Cheddar Man. In the late 1990s, Oxford University geneticist Brian Sykes sequenced mitochondrial DNA from one of Cheddar Man’s molars.

Mitochondrial DNA comes from the biological “batteries” within our cells and is passed down exclusively from a mother to her children.

Prof Sykes compared the ancient genetic information with DNA from 20 living residents of Cheddar village and found two matches – including history teacher Adrian Targett, who became closely connected with the discovery. The result is consistent with the approximately 10% of Europeans who share the same mitochondrial DNA type.

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The term “Europe”

This word has had a very interesting history. Now it has a more or less concrete definition, complete with boundaries, maps and dictionaries to back it up. But it wasn’t always this way. Even today there’s no physical boundary between it and Asia. Consider this quote from Wikipedia (bolding mine):

“Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, and the Mediterranean Sea to the south. The eastern boundary with Asia is a historical and cultural construct, as there is no clear physical and geographical separation between them; Europe is generally considered as separated from Asia by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways of the Turkish Straits.[4] Yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. The primarily physiographic term “continent” as applied to Europe also incorporates cultural and political elements whose discontinuities are not always reflected by the continent’s current overland boundaries.”

– Taken from https://en.wikipedia.org/wiki/Europe, 4th May 2017

Continue reading The term “Europe”

Fair skin doesn’t do shit for vit D levels

(Reposted from https://www.ucsf.edu/news/2014/06/115741/human-evolution-changes-skin’s-barrier-set-northern-europeans-apart)

In Human Evolution, Changes in Skin’s Barrier Set Northern Europeans Apart

UCSF Study Questions Role of Skin Pigment in Enabling Survival at Higher Latitudes

 

A microscopic image of skin cells.

 

The popular idea that Northern Europeans developed light skin to absorb more UV light so they could make more vitamin D – vital for healthy bones and immune function – is questioned by UC San Francisco researchers in a new study published online in the journal Evolutionary Biology.

Ramping up the skin’s capacity to capture UV light to make vitamin D is indeed important, according to a team led by Peter Elias, MD, a UCSF professor of dermatology. However, Elias and colleagues concluded in their study that changes in the skin’s function as a barrier to the elements made a greater contribution than alterations in skin pigment in the ability of Northern Europeans to make vitamin D.

Elias’ team concluded that genetic mutations compromising the skin’s ability to serve as a barrier allowed fair-skinned Northern Europeans to populate latitudes where too little ultraviolet B (UVB) light for vitamin D production penetrates the atmosphere.

Among scientists studying human evolution, it has been almost universally assumed that the need to make more vitamin D at Northern latitudes drove genetic mutations that reduce production of the pigment melanin, the main determinant of skin tone, according to Elias.

“At the higher latitudes of Great Britain, Scandinavia and the Baltic States, as well as Northern Germany and France, very little UVB light reaches the Earth, and it’s the key wavelength required by the skin for vitamin D generation,” Elias said.

“While it seems logical that the loss of the pigment melanin would serve as a compensatory mechanism, allowing for more irradiation of the skin surface and therefore more vitamin D production, this hypothesis is flawed for many reasons,” he continued. “For example, recent studies show that dark-skinned humans make vitamin D after sun exposure as efficiently as lightly-pigmented humans, and osteoporosis – which can be a sign of vitamin D deficiency – is less common, rather than more common, in darkly-pigmented humans.”

Furthermore, evidence for a south to north gradient in the prevalence of melanin mutations is weaker than for this alternative explanation explored by Elias and colleagues.

In earlier research, Elias began studying the role of skin as a barrier to water loss. He recently has focused on a specific skin-barrier protein called filaggrin, which is broken down into a molecule called urocanic acid – the most potent absorber of UVB light in the skin, according to Elias. “It’s certainly more important than melanin in lightly-pigmented skin,” he said.

In their new study, the researchers identified a strikingly higher prevalence of inborn mutations in the filaggrin gene among Northern European populations. Up to 10 percent of normal individuals carried mutations in the filaggrin gene in these northern nations, in contrast to much lower mutation rates in southern European, Asian and African populations.

Moreover, higher filaggrin mutation rates, which result in a loss of urocanic acid, correlated with higher vitamin D levels in the blood. Latitude-dependent variations in melanin genes are not similarly associated with vitamin D levels, according to Elias. This evidence suggests that changes in the skin barrier played a role in Northern European’s evolutionary adaptation to Northern latitudes, the study concluded.

Yet, there was an evolutionary tradeoff for these barrier-weakening filaggrin mutations, Elias said. Mutation bearers have a tendency for very dry skin, and are vulnerable to atopic dermatitis, asthma and food allergies. But these diseases have appeared only recently, and did not become a problem until humans began to live in densely populated urban environments, Elias said.

The Elias lab has shown that pigmented skin provides a better skin barrier, which he says was critically important for protection against dehydration and infections among ancestral humans living in sub-Saharan Africa. But the need for pigment to provide this extra protection waned as modern human populations migrated northward over the past 60,000 years or so, Elias said, while the need to absorb UVB light became greater, particularly for those humans who migrated to the far North behind retreating glaciers less than 10,000 years ago.

The data from the new study do not explain why Northern Europeans lost melanin. If the need to make more vitamin D did not drive pigment loss, what did? Elias speculates that, “Once human populations migrated northward, away from the tropical onslaught of UVB, pigment was gradually lost in service of metabolic conservation. The body will not waste precious energy and proteins to make proteins that it no longer needs.”

For the Evolutionary Biology study, labeled a “synthesis paper” by the journal, Elias and co-author Jacob P. Thyssen, MD, a professor at the University of Copenhagen, mapped the mutation data and measured the correlations with blood levels of vitamin D. Labs throughout the world identified the mutations. Daniel Bikle, MD, PhD, a UCSF professor of medicine, provided expertise on vitamin D metabolism.

The research was funded by the San Francisco Veterans Affairs Medical Center, the Department of Defense, the National Institutes of Health, and by a Lundbeck Foundation grant.

UCSF is the nation’s leading university exclusively focused on health. Now celebrating the 150th anniversary of its founding as a medical college, UCSF is dedicated to transforming health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. It includes top-ranked graduate schools of dentistry, medicine, nursing and pharmacy; a graduate division with world-renowned programs in the biological sciences, a preeminent biomedical research enterprise and two top-tier hospitals, UCSF Medical Center and UCSF Benioff Children’s Hospital San Francisco.

 

 

 

 

 

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