
How We Got Here: DNA Points to a Single Migration From Africa - andyraskin
http://www.nytimes.com/2016/09/22/science/ancient-dna-human-history.html
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mborch
"However, neither Mallick et al. nor Malaspinas et al. exclude the possibility
of multiple out-of-Africa dispersals." (from the commentary).

How is that one wave?

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dnautics
yeah, i doubt the thesis. The egyptians certainly left africa in several
waves, and it's unbelievable that there wasn't genetic mixing between egypt
and subsaharan africa.

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dogma1138
What are exactly egyptians in your case? Much of the mediterranean basin
including modern Turkey, Syria, Lebanon, Israel/Palestine, Egypt, and the rest
of N. Africa was also settled by "Europeans". Egypt itself went through
multiple periods including Persian, Canaanite, and Hellenic periods. Overall
you need to be very specific of the period because there was a lot of influx
and movement of people and civilizations.

Even in the past 2000 years there were huge demographic changes in Egypt, the
Egyptians today are not an entirely good representation of Egypt even 2000
years ago during the Coptic period.

The changes in skin tone, physique and facial characteristics in Egyptian art
are quite interesting to see and they represent the changes in the ethnic and
demographic makeup of the civilization.

For example late period mummies and portraits show the outcome of genetic
influx from Hellenic and Roman cultures into Egypt
[https://en.wikipedia.org/wiki/Fayum_mummy_portraits](https://en.wikipedia.org/wiki/Fayum_mummy_portraits),
this is even more interesting since Faiyum is quite far from the coast line
which shows that demographic changes spanned the geography of egypt.

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dnautics
so, basically you made my point for me.

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contingencies
_We know there were multiple dispersals out of Africa, but we can trace our
ancestry back to a single one._

How does that work? Everyone else died? What about recently discovered groups
like the Red Deer Cave People?
[https://en.wikipedia.org/wiki/Red_Deer_Cave_people](https://en.wikipedia.org/wiki/Red_Deer_Cave_people)

Doesn't evidence exist that groups interbreed, at least Denisovans /
Neanderthals / Modern Humans?

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flukus
I thinks it's "all extent modern humans migrated in one wave", they also
bumped uglies with a few other not so modern species along the way.

Personally I want to see more study into mungo man
([https://en.wikipedia.org/wiki/Lake_Mungo_remains](https://en.wikipedia.org/wiki/Lake_Mungo_remains)),
that has some potential to upset things.

~~~
contingencies
_In 1988, the skeleton of a child believed to be contemporary with Mungo man
was discovered. Investigation of the remains was blocked by the 3TTG [ie.
Three Traditional Tribal Groups] with the remains subsequently protected but
remaining in-situ. An adult skeleton was exposed by erosion in 2005 but by
late 2006 had been completely destroyed by wind and rain. This loss resulted
in the indigenous custodians receiving a government grant of $735,000 to
survey and improve the conservation of skeletons, hearths and middens that
were eroding from the dunes. Conservation is in-situ and no research is
permitted._

Sounds like the local aboriginal tribes are claiming ownership of remains that
predate them, that they never knew were there anyway, and blocking further
research. Thanks guys.

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hownottowrite
The commentary referenced in the article is far better than the article
itself: [http://bit.ly/2cWOXmj](http://bit.ly/2cWOXmj)

[0] short url provided for insanely long paywall avoiding link in the nyt OP

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mc32
I wonder how this would tie in to the human bottleneck theory. According to
this theory[1], somewhere between 100,000 to 50,000 years ago, we had a human
genetic bottleck event where there were only about 10 000 individuals left on
the planet.

If true, we're one lucky species.

[1][https://en.wikipedia.org/wiki/Toba_catastrophe_theory](https://en.wikipedia.org/wiki/Toba_catastrophe_theory)

~~~
m_mueller
Wasn't that discredited? From your link:

> Other research has cast doubt on a link between Toba and a genetic
> bottleneck. For example, ancient stone tools in southern India were found
> above and below a thick layer of ash from the Toba eruption and were very
> similar across these layers, suggesting that the dust clouds from the
> eruption did not wipe out this local population.

~~~
mc32
It's fair to say scientists have cast doubt on the theory but I don't think it
has been completely discredited[1]? I could be wrong, so any elucidation would
be great.

At least it's an interesting thought. Or maybe it's just wistful thinking.

[1][https://whyevolutionistrue.wordpress.com/2011/09/18/how-
big-...](https://whyevolutionistrue.wordpress.com/2011/09/18/how-big-was-the-
human-population-bottleneck-not-anything-close-to-2/)

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onetime20160931
I can't read the full article. Even with all my cookies cleared it takes me to
a subscription page. Same with web search. What's up with this?

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EarthIsHome
You may have read all your free articles for the month. The NYT is a paid
subscription newspaper but they offer a handful of articles a month for free.

If you enjoy the NYT and read it often, think about subscribing.

~~~
gruez
...and how do they keep track of how many articles each person read each
month? Oh right, by cookies.

~~~
imaginenore
There are other ways. Local storage, indexedDB, WebSQL, browser
fingerprinting.

~~~
M_Grey
Control your cookies, dump your storage, Scriptblocker, uBlock Origin, and
Random Agent Spoofer.

~~~
DrJokepu
Or just open it in incognito mode / private browsing.

~~~
vacri
Or just subscribe.

(though private mode is the easiest way)

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ertttddfgdf
Don't have the ref. onhand but read recently that African populace shows the
greatest genetic diversity in _Homo sapiens sapiens_.

India comes in at second place, presumably because of larger migration to the
subcontinent compared to Europe.

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reflexive
Africa is home to the tallest (Sudanese) and shortest (pygmy) humans. You can
think of the entire non-African population as a little inbred offshoot of the
main stock.

I recommend E. O. Wilson's "Social Conquest of Earth" as a reference for
quantifying the genetic difference within and between populations.

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FullMtlAlcoholc
I wouldn't necessarily call them inbred. Whites crossbred with Neanderthals
and Asians did the same with some other related Homo genus whose name escapes
me.

Doesn't surprise me that both went extinct. If we're still this prejudiced
towards each other in the 21st century, I have little doubt that we played a
large role in their extinction

~~~
reflexive
Denisovans (Homo Altai / Homo sapiens Denisova).

You make a good point that the emigrants did mix in a peppering of genes from
their early-arriving distant cousins. But overall, only a tiny fraction of the
available gene pool made it out of Africa.

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solarengineer
I often wonder how people reconcile such scientific reports with what
religious texts say.

Some weeks ago, while discussing with a colleague about the human tendency for
discrimination on any grounds, I'd said "After all, we humans were once apes
in Africa". He responded with "Hey, I'm a follower of so-and-so religion, and
our religious text says that God made everything within a week. So, please
let's not discuss topics that are hurtful to me".

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linkregister
To get pedantic, humans were never apes, they share a common ancestor with
apes.

And you could reconcile with your colleague, "I'm not disputing God created
everything within a week; I'm just saying that all the evidence makes it look
like it happened over the course of millions of years. Maybe God had some
accelerated process, does your religious text talk about how God went about
creation?"

~~~
spqr0a1
To get extra pedantic we _are_ apes. Taxonomically, humans are in the great
ape family _Hominidae_.

We were, however, never monkeys.

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vacri
Eddie Izzard points out that the French don't distinguish between monkeys and
apes... and then goes on to suggest that the French translation for a line in
Planet of the Apes must be interesting: "We are not monkeys! We are apes!"

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dschiptsov
And Australian Bushmen, Polynesians, south Indians show us the multiple waves
of migration, but who are they compared to a fancy statistical model made from
poorly understood DNA sequences by clever hipsters!

