Wednesday, 11 April 2018

Ancient DNA



From BBC News - How ancient DNA is transforming our view of the past, Paul Rincon

"Prof David Reich of Harvard Medical School is one of the leading lights in the field of ancient DNA. His team's work has cast a new perspective on human history, reconstructing the epic migrations and genetic exchanges that shaped the people of different regions worldwide".


DNA Explained, Genetic Genealogy  - Thanks to Graham for the link, and the following link

Concepts – Calculating Ethnicity Percentages

The Beaker phenomenon and the genomic transformation of northwest Europe, Nature, Nature, volume 555, pages 190–196 (08 March 2018)

Abstract:

"From around 2750 to 2500 BC, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 BC. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain’s gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries".


Iron Age study targets British DNA mystery, Paul Rincon, Science editor, BBC News website

"Prof Reich said his team currently had three working hypotheses to explain the result. While the Beakers replaced around 90% of the ancestry in Britain, it's possible that a pocket (or pockets) of Neolithic farmers held out in isolation somewhere for hundreds of years. During the Iron Age (which began around 3,000 years ago), they mixed back in with the general population, diluting the Beakers' genetic background with a type of ancestry that's now stronger around the Mediterranean than in Northern or Central Europe. Alternatively, the genetic data may be hinting at a separate migration from continental Europe during the Iron Age - perhaps one that brought Celtic languages into Britain.
The third possibility is that scholars have simply underestimated the genetic impact of the Roman occupation, which lasted in Britain from AD 43 until 410. Roman settlers from the Italian peninsula would have traced a large proportion of their ancestry to Neolithic farmers like those that inhabited Britain before the arrival of the Beaker people".


Ground-breaking research on ‘Beaker People’, Wiltshire Museum, Devizes


Über Vergänglichkeit
Noch spür ich ihren Atem auf den Wangen:
Wie kann das sein, daß diese nahen Tage
Fort sind, für immer fort, und ganz vergangen?

Dies ist ein Ding, das keiner voll aussinnt,
Und viel zu grauenvoll, als daß man klage:
Daß alles gleitet und vorüberrinnt.

Und daß mein eignes Ich, durch nichts gehemmt,
Herüberglitt aus einem kleinen Kind,
Mir wie ein Hund unheimlich stumm und fremd.

Dann: daß ich auch vor hundert Jahren war
Und meine Ahnen, die im Totenhemd,
Mit mir verwandt sind wie mein eignes Haar,

So eins mit mir als wie mein eignes Haar.


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