Does David Reich contradict Nicholas Wade?

[sevensages]

Last year I read Nicholas Wade's book Before the Dawn. Before the Dawn is about the history of humanity in prehistoric times.

I am currently reading David Reich's book Who We Are and How we Got Here. Who we Are and How we Got Here is also about the history of humanity in prehistoric times.

In Before the Dawn, Wade wrote the following: "The Richards team's reconstruction of the population history of Europe brought to light an unexpected fact: that most Europeans are descended from the first settlers who arrived during the Upper Paleolithic Era. Only a minority arrived during the Neolithic age."

In Who We Are and How We Got Here, David Reich wrote the following: "The extraordinary fact that emerges from ancient DNA is that just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not yet arrived" (107).

Is it just my imagination, or does the quote by David Reich contradict the quote by Nicholas Wade? If the two quotes don't contradict each other, please reconcile them for me. I don't see how those two quotes don't contradict each other.

If there is a contradiction, I suppose the consensus is probably that David Reich is correct since David Reich had access to ancient DNA that Nicholas Wade did not have access to. Who We Are and How we Got Here was published in 2018. IIRC, Before the Dawn was published circa 2006.

If there is a contradiction, is the consensus among geneticists that Reich's assertion is correct and Wade's assertion is false?

 

[Andrew Mason]

There is a difference, not necessarily a total contradiction. Based on genetic analysis of European skeletons older than 5000 years, inhabitants of Europe before about 3000 BC had mixed genes from hunter-gatherers and Anatolian farmers. Both authors agree on that. Hunter-gatherers arrived in the upper paleolithic (around the end of the ice-age 15000-10000 years ago) and Anatolian Farmers arrived in the early neolithic period about 7,000-9,000 years ago from what is now Turkey.

According to Reich the genetic evidence is that most modern Europeans are descended from migrants from the steppe regions of eastern Europe and Asia beginning about 5,000 years ago. Reich estimates Europeans today have genes that are 75% Steppe and 25% hunter-gatherer / Anatolian farmer.

The issue seems to be the size of the Steppe migration and, possibly, the extent to which the Steppe arrivals mixed genes with the hunter-gatherer and Anatolian farmer locals. The genetic data that establishes the wave of Steppe migration beginning around 3000 BC was not available in 2006 when Wade published "Before the Dawn".

Wade uses limited DNA evidence done in the early 2000s - mainly of Y chromosomes and mitochondial DNA - to reach his conclusion that most modern Europeans can trace their ancestry back to the hunter-gatherers. But he was certainly aware there had been later migrations.

It should be noted that Wade is not a geneticist. He is a science writer who worked for the New York Times. Reich, who is a geneticist, used a lot more genetic evidence and more recent data, to reach his conclusions.

AM

 

[sevensages]

There is a difference, not necessarily a total contradiction.

I don't see how there is not a contradiction.

Based on genetic analysis of European skeletons older than 5000 years, inhabitants of Europe before about 3000 BC had mixed genes from hunter-gatherers and Anatolian farmers. Both authors agree on that. Hunter-gatherers arrived in the upper paleolithic (around the end of the ice-age 15000-10000 years ago) and Anatolian Farmers arrived in the early neolithic period about 7,000-9,000 years ago from what is now Turkey.

According to Reich the genetic evidence is that most modern Europeans are descended from migrants from the steppe regions of eastern Europe and Asia beginning about 5,000 years ago. Reich estimates Europeans today have genes that are 75% Steppe and 25% hunter-gatherer / Anatolian farmer.

The issue seems to be the size of the Steppe migration and, possibly, the extent to which the Steppe arrivals mixed genes with the hunter-gatherer and Anatolian farmer locals. The genetic data that establishes the wave of Steppe migration beginning around 3000 BC was not available in 2006 when Wade published "Before the Dawn".

Wade uses limited DNA evidence done in the early 2000s - mainly of Y chromosomes and mitochondial DNA - to reach his conclusion that most modern Europeans can trace their ancestry back to the hunter-gatherers. But he was certainly aware there had been later migrations.

I think that you are aware of the fact that there is not a modern European on the face of the Earth today that can trace all of their ancestry back to the hunter-gatherers. Don't you mean the following?: "Wade uses limited DNA evidence done in the early 2000s - mainly of Y chromosomes and mitochondrial DNA - to reach his conclusion that modern Europeans can trace MOST of their ancestry back to the hunter-gatherers."

It should be noted that Wade is not a geneticist. He is a science writer who worked for the New York Times. Reich, who is a geneticist, used a lot more genetic evidence and more recent data, to reach his conclusions.

AM

Let's review again what Wade wrote. Wade wrote the following: "The Richards team's reconstruction of the population history of Europe brought to light an unexpected fact: That most Europeans are descended from the first settlers who arrived during the Upper Paleolithic era. Only a minority arrived during the Neolithic age."

In the interests of brevity, henceforth, I am going to call people of European descent white people in this post because all people of European descent are white, and all white people are of European descent.

So Wade's statement basically says the following: "Most white people are descended from the first settlers who arrived during the Upper Paleolithic era. Only a minority arrived during the Neolithic age." ----

I don't think that Wade quote can be taken literally because if Wade's quote is taken literally, it is extremely obvious that it is false. Any white person is descended from literally millions of people five thousand years ago. Wade statement makes it sound like most white people are descended STRICTLY from the first settlers who arrived during the Upper Paleolithic era without being descended from any settlers who arrived during the Neolithic age. There is not even one white person on the face of the Earth who is descended strictly from the first settlers who arrived during the Upper Paleolithic era without being descended from any settlers who arrived during the Neolithic age. ALL white people on Earth are descended from BOTH settlers who arrived in the Upper Paleolithic era and from settlers who arrived during the Neolithic age.

I interpret Wade's statement as meaning the following: "Most white people are PRIMARILY descended from the first settlers who arrived during the Upper Paleolithic era. Only a minority of the ancestors of white people arrived in Europe during the Neolithic age." ------Do you agree with my interpretation of Wade's statement?

Reich's statement is that "the extraordinary fact that emerges from ancient DNA is that just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not arrived."

I don't see how the two statements don't totally contradict each other unless one wants to argue that they don't contradict each other because Wade was writing about all people of European descent while Reich was writing ONLY about people of NORTHERN European descent.

If the people who are now the primary ancestors of all white people had not yet arrived in Europe five thousand years ago, then it cannot be true that most of the primary ancestors of all white people arrived during the Upper Paleolithic era about 15,000-10,000 years ago. I cannot figure out why you don't think that there is a contradiction between the two statements.

Can you or someone else reconcile these two statements for me?

P.S. I think that Wade's statement is kind of sloppy writing. I think that Reich's statement is a lot more precise writing.

 

[Andrew Mason]

I don't see how there is not a contradiction.

It depends on whether these statements can be true: 1. "most Europeans are descended from the first settlers who arrived during the Upper Paleolithic Era. " and 2. "Only a minority arrived during the Neolithic age." by Wade and 3. "... just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not yet arrived" by Reich.

If the neolithic Steppe migrants arrived in smaller numbers but mixed well with the existing population, then the first, second and third statements can all be true. That is because the term "primary ancestors" is understood to mean “most recent”.

I think that you are aware of the fact that there is not a modern European on the face of the Earth today that can trace all of their ancestry back to the hunter-gatherers. Don't you mean the following?: "Wade uses limited DNA evidence done in the early 2000s - mainly of Y chromosomes and mitochondrial DNA - to reach his conclusion that modern Europeans can trace MOST of their ancestry back to the hunter-gatherers."

Wade refers to “most Europeans” not “most of their ancestry”. The former simply says that most Europeans have genes from the hunter-gatherers. The latter refers to the relative proportion of genes from hunter-gatherers being greater than those of the late Neolithic arrivals.

I interpret Wade's statement as meaning the following: "Most white people are PRIMARILY descended from the first settlers who arrived during the Upper Paleolithic era. Only a minority of the ancestors of white people arrived in Europe during the Neolithic age." ------Do you agree with my interpretation of Wade's statement?

No. Primary ancestors are the most recent ancestors.

Reich's statement is that "the extraordinary fact that emerges from ancient DNA is that just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not arrived."

I don't see how the two statements don't totally contradict each other unless one wants to argue that they don't contradict each other because Wade was writing about all people of European descent while Reich was writing ONLY about people of NORTHERN European descent.

If the people who are now the primary ancestors of all white people had not yet arrived in Europe five thousand years ago, then it cannot be true that most of the primary ancestors of all white people arrived during the Upper Paleolithic era about 15,000-10,000 years ago. I cannot figure out why you don't think that there is a contradiction between the two statements.

Can you or someone else reconcile these two statements for me?

P.S. I think that Wade's statement is kind of sloppy writing. I think that Reich's statement is a lot more precise writing.

You appear to be treating Reich’s reference to “primary ancestors” as “earliest known ancestors”. In DNA geneolgy, "earliest known" ancestors refers to the furthest person back that a researcher has identified in a specific direct paternal (Y-DNA) or direct maternal (mtDNA) line. It seems to me that this is what Wade is referring to but not Reich. Reich is referring to most recent ancestors contributing to the genes of modern Europeans.

AM

 

[sevensages]

It depends on whether these statements can be true: 1. "most Europeans are descended from the first settlers who arrived during the Upper Paleolithic Era. " and 2. "Only a minority arrived during the Neolithic age." by Wade and 3. "... just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not yet arrived" by Reich.

If the neolithic Steppe migrants arrived in smaller numbers but mixed well with the existing population, then the first, second and third statements can all be true. That is because the term "primary ancestors" is understood to mean “most recent”.

What do you think that "Only a minority arrived during the Neolithic age" means? My interpretation is that Wade meant that "Only a minority of the most recent ancestors of white people arrived during the Neolithic age".

Wade refers to “most Europeans” not “most of their ancestry”.

Yes, but I think that Wade meant "most of their ancestry". Otherwise, I don't see the point in those statements, and the statements don't make much sense to me. I think that it was just sloppy writing on Wade's part.

The former simply says that most Europeans have genes from the hunter-gatherers. The latter refers to the relative proportion of genes from hunter-gatherers being greater than those of the late Neolithic arrivals.


No. Primary ancestors are the most recent ancestors.

You appear to be treating Reich’s reference to “primary ancestors” as “earliest known ancestors”. In DNA geneolgy, "earliest known" ancestors refers to the furthest person back that a researcher has identified in a specific direct paternal (Y-DNA) or direct maternal (mtDNA) line. It seems to me that this is what Wade is referring to but not Reich. Reich is referring to most recent ancestors contributing to the genes of modern Europeans.

AM

Reich wrote "The extraordinary fact that emerges from ancient DNA is that just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not arrived".

By "primary ancestors" in the above quote by Reich, I think that Reich meant the group of people that comprised the majority of the ancestors of white people five thousand years ago.

 

[Andrew Mason]

What do you think that "Only a minority arrived during the Neolithic age" means? My interpretation is that Wade meant that "Only a minority of the most recent ancestors of white people arrived during the Neolithic age".

This graphic from the paper published in Nature in 2015 may help explain the data that Reich was using:

The green bars represent the proportion of genes in the populations in the stated country or region added from migrants from the steppe regions of eastern Europe and Asia (Yamnaya); The orange bars represent the proportion of genes in the stated country or region added from the migration from early Neolithic Anatolian farmers; The blue bars represent the proportion of genes in the populations in the stated country or region contributed from western European hunter-gatherers.

In addition to genetic data, one can also look at languages and similarity of words used to describe common things. The Nature paper discusses these. For example:

"The best argument for the‘Anatolian hypothesis’ that Indo-European languages arrived in Europe from Anatolia∼8,500 years ago is that major language replacements are thought to require major migrations, and that after the Early Neolithic when farmers established themselves in Europe, the population base was likely to have been so large that later migrations would not have made much of an impact. However, our study shows that a later major turnover did occur, and that steppe migrants replaced∼75% of the ancestry of central Europeans. An alternative theory is the‘steppe hypothesis’, which proposes that early Indo-European speakers were pastoralists of the grasslands north of the Black and Caspian Seas, and that their languages spread into Europe after the invention of wheeled vehicles. Our results make a compelling case for the steppe as a source of at least some of the Indo-European languages in Europe by documenting a massive migration ∼4,500 years ago associated with the Yamnaya and Corded Ware cultures, which are identified by proponents of the steppe hypothesis as vectors for the spread of Indo-European languages into Europe. These results challenge the Anatolian hypothesis by showing that not all Indo-European languages in Europe can plausibly derive from the first farmer migrations thousands of years earlier (Supplementary Information section11). We caution that the location of the proto-Indo-European homeland that also gave rise to the Indo-European languages of Asia, as well as the Indo-European languages of southeastern Europe, cannot be determined from the data reported here (Supplementary Information section 11)."

AM