DNA Sequencing Megathread! Neanderthals, Denisovans and other ancient DNA!

Started by jimmy olsen, November 03, 2013, 07:07:43 PM

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The Minsky Moment

Quote from: jimmy olsen on January 06, 2016, 06:04:23 PM
We were not talking about the modern period, though I note that the Anglo-Saxon invasion of North America and the following waves of European immigration seems to have been rather successful, we were talking about the Neolirhic period in which there were massive waves of migration from the Near East and the Steppe into Europe by early farmers and pastoralists.

The reference to "massive waves of migration" is question begging. 
The DNA evidence is ambiguous, and there remains a very lively academic debate between the demic diffusion and cultural diffusion hypotheses (as well as many positions in between).  And even if widespread "Near Eastern" genetic markers could be established beyond any doubt - as yet far from the case - it doesn't necessarily imply "massive waves" if one assumed that Mesolithic population levels in Europe were not enormous to begin with.
The purpose of studying economics is not to acquire a set of ready-made answers to economic questions, but to learn how to avoid being deceived by economists.
--Joan Robinson

jimmy olsen

Quote from: The Minsky Moment on January 06, 2016, 06:22:13 PM
Quote from: jimmy olsen on January 06, 2016, 06:04:23 PM
We were not talking about the modern period, though I note that the Anglo-Saxon invasion of North America and the following waves of European immigration seems to have been rather successful, we were talking about the Neolirhic period in which there were massive waves of migration from the Near East and the Steppe into Europe by early farmers and pastoralists.

The reference to "massive waves of migration" is question begging. 
The DNA evidence is ambiguous, and there remains a very lively academic debate between the demic diffusion and cultural diffusion hypotheses (as well as many positions in between).  And even if widespread "Near Eastern" genetic markers could be established beyond any doubt - as yet far from the case - it doesn't necessarily imply "massive waves" if one assumed that Mesolithic population levels in Europe were not enormous to begin with.

Scale is relative, if it's big enough to overwhelm the natives it counts as massive, even if the number of natives was never that large.
It is far better for the truth to tear my flesh to pieces, then for my soul to wander through darkness in eternal damnation.

Jet: So what kind of woman is she? What's Julia like?
Faye: Ordinary. The kind of beautiful, dangerous ordinary that you just can't leave alone.
Jet: I see.
Faye: Like an angel from the underworld. Or a devil from Paradise.
--------------------------------------------
1 Karma Chameleon point

The Minsky Moment

Scale is relative to a point.

Imagine a scenario where small groups of cultivators are gradually drifting west, towards "virgin lands." If you also assume these people have a technological advantage that permits higher reproduction rates, then over the course of a couple thousand years there can be a significant infusion of new genetic types.  But it's hard to call such a scenario "waves of mass migration" with a straight face.
The purpose of studying economics is not to acquire a set of ready-made answers to economic questions, but to learn how to avoid being deceived by economists.
--Joan Robinson

Caliga

Quote from: Queequeg on January 06, 2016, 11:23:09 AM
This is reflected in some sense in my own heritage.  My mom's family is, if you go back far enough, from NE/NC England, the old Danelaw, and that's probably the reason I'm tall and blonde. 
My English heritage is primarily from Norfolk and the West Riding in Yorkshire.  People used to call my Uncle 'The Viking' because of his light blonde hair and blue eyes.
0 Ed Anger Disapproval Points

Caliga

Quote from: jimmy olsen on January 05, 2016, 11:16:37 PM
Because we've met in person?  :huh:

Also, you're not shy about your German heritage.
How do you know I'm not descended from colonial Namibians? :)
0 Ed Anger Disapproval Points

Malthus

Quote from: The Minsky Moment on January 06, 2016, 06:38:02 PM
Scale is relative to a point.

Imagine a scenario where small groups of cultivators are gradually drifting west, towards "virgin lands." If you also assume these people have a technological advantage that permits higher reproduction rates, then over the course of a couple thousand years there can be a significant infusion of new genetic types.  But it's hard to call such a scenario "waves of mass migration" with a straight face.

No one ever theorizes from the DNA evidence that some folks were just hotter than others.  :D Mesolithic rock stars, if you will.  ;)
The object of life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane—Marcus Aurelius

jimmy olsen

Quote from: Malthus on January 07, 2016, 04:23:48 PM
Quote from: The Minsky Moment on January 06, 2016, 06:38:02 PM
Scale is relative to a point.

Imagine a scenario where small groups of cultivators are gradually drifting west, towards "virgin lands." If you also assume these people have a technological advantage that permits higher reproduction rates, then over the course of a couple thousand years there can be a significant infusion of new genetic types.  But it's hard to call such a scenario "waves of mass migration" with a straight face.

No one ever theorizes from the DNA evidence that some folks were just hotter than others.  :D Mesolithic rock stars, if you will.  ;)

Blue eyes originated just 8,000 years ago. IIRC I haven't seen any other theory for the vast spread of that trait in such a short period of time outside of sexual selection.
It is far better for the truth to tear my flesh to pieces, then for my soul to wander through darkness in eternal damnation.

Jet: So what kind of woman is she? What's Julia like?
Faye: Ordinary. The kind of beautiful, dangerous ordinary that you just can't leave alone.
Jet: I see.
Faye: Like an angel from the underworld. Or a devil from Paradise.
--------------------------------------------
1 Karma Chameleon point

Razgovory

I've given it serious thought. I must scorn the ways of my family, and seek a Japanese woman to yield me my progeny. He shall live in the lands of the east, and be well tutored in his sacred trust to weave the best traditions of Japan and the Sacred South together, until such time as he (or, indeed his house, which will periodically require infusion of both Southern and Japanese bloodlines of note) can deliver to the South it's independence, either in this world or in space.  -Lettow April of 2011

Raz is right. -MadImmortalMan March of 2017

jimmy olsen

It is far better for the truth to tear my flesh to pieces, then for my soul to wander through darkness in eternal damnation.

Jet: So what kind of woman is she? What's Julia like?
Faye: Ordinary. The kind of beautiful, dangerous ordinary that you just can't leave alone.
Jet: I see.
Faye: Like an angel from the underworld. Or a devil from Paradise.
--------------------------------------------
1 Karma Chameleon point

Razgovory

I've given it serious thought. I must scorn the ways of my family, and seek a Japanese woman to yield me my progeny. He shall live in the lands of the east, and be well tutored in his sacred trust to weave the best traditions of Japan and the Sacred South together, until such time as he (or, indeed his house, which will periodically require infusion of both Southern and Japanese bloodlines of note) can deliver to the South it's independence, either in this world or in space.  -Lettow April of 2011

Raz is right. -MadImmortalMan March of 2017

Syt

http://www.nytimes.com/2016/01/08/science/otzi-the-iceman-stomach-bacteria-europe-migration.html?smid=fb-nytimes&smtyp=cur&_r=0

QuoteÖtzi the Iceman's Stomach Bacteria Offers Clues on Human Migration

An insight into the peopling of Europe has emerged from an unlikely source — the stomach contents of a 5,300-year-old body pulled from a thawing glacier in the eastern Italian Alps.

Since his discovery in 1991, Ötzi the Iceman, as he was named, has provided a trove of information about the life of Europeans at that time. His long-frozen tissues have now yielded another surprise: Scientists have been able to recover from his stomach samples of Helicobacter pylori, a bacterium that infects about half the human population and can occasionally cause stomach ulcers.

The bacterium is transmitted only through intimate contact, and its distribution around the world matches almost perfectly the distribution of human populations. The bacterium's genetic variations are therefore used by researchers as a supplement to human genetics in tracking ancient human migrations.

Researchers led by Frank Maixner and Albert Zink of the Institute for Mummies and the Iceman, at the European Research Academy in Bolzano, Italy, reported on Thursday in Science that they had been able to reconstruct the entire DNA sequence of the ulcer bacterium from samples taken from the iceman's stomach.

Modern-day Europeans carry a type of H. pylori that is a hybrid of two ancient strains, one of which originated somewhere in Eurasia and the other in Africa, after modern humans first left that continent about 50,000 years ago.

One theory is that this hybridization occurred in the Middle East before or during the Last Glacial Maximum, a catastrophically cold period during the last ice age when glaciers swept south and made much of Europe uninhabitable.

After the glaciers began to retreat, about 20,000 years ago, people from the Middle East and other southern refuges moved north to recolonize Europe. It could have been these migrants who brought the hybridized ulcer bacterium to Europe.

Yet the ulcer bacterium from Ötzi is related only to the Eurasian strain, the researchers found, implying that hybridization with the African strain must have occurred much later, within the last 5,000 years.

The finding suggests that it may have been the first farmers, who brought the agricultural revolution to Europe from the Middle East starting about 8,000 years ago, who were the carriers of the African strain, said Yoshan Moodley of the University of Venda in South Africa, a co-author of the new report.

Reconstructing the history of human pathogens, a new science made possible by the ability to decode DNA molecules many thousands of years old, can yield deep insights into both medicine and history. Last October a team led by Eske Willerslev of the University of Copenhagen extracted Yersinia pestis, the plague bacterium, from human teeth up to 5,000 years old.

The plague bacterium, spread by fleas and rats, caused three devastating pandemics — the Justinian plague of the sixth century, the Black Death in 14th-century Europe and the global pandemic that erupted in the 1890s.

Mark Achtman, a leading expert on ancient pathogens at the University of Warwick in England, said that the authors of the Ötzi paper had done well to extract the ulcer bacterium from the iceman, but that it was difficult to infer from a single sample anything about the bacterium's distribution in Europe 5,000 years ago.

Besides looking at the DNA of the ulcer bacterium, the authors also found proteins in the iceman's stomach that are involved in inflammation, but the stomach is too poorly preserved to confirm that he suffered from gastric disease.
I am, somehow, less interested in the weight and convolutions of Einstein's brain than in the near certainty that people of equal talent have lived and died in cotton fields and sweatshops.
—Stephen Jay Gould

Proud owner of 42 Zoupa Points.

The Brain

QuoteAfter the glaciers began to retreat, about 20,000 years ago, people from the Middle East and other southern refuges moved North

We can only imagine what this must have looked like.
Women want me. Men want to be with me.

Duque de Bragança

Quote from: The Brain on January 08, 2016, 06:12:13 AM
QuoteAfter the glaciers began to retreat, about 20,000 years ago, people from the Middle East and other southern refuges moved North

We can only imagine what this must have looked like.

As bad as the invasion of Germanic peoples or Völkerwanderung?  :smarty:

The Minsky Moment

Quote from: The Brain on January 08, 2016, 06:12:13 AM
QuoteAfter the glaciers began to retreat, about 20,000 years ago, people from the Middle East and other southern refuges moved North

We can only imagine what this must have looked like.

Lots of whining from Alternative fur Magdalenia
The purpose of studying economics is not to acquire a set of ready-made answers to economic questions, but to learn how to avoid being deceived by economists.
--Joan Robinson

lustindarkness

Grand Duke of Lurkdom