Thursday, October 30, 2014

[tt] Apology

I apologize for just sending messages that have little to do with
transhumanist technology or related matters such as human evolution and
cosmology.

Frank

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[tt] The Jewish Chronicle: Was Sartre indifferent about the Holocaust?

Was Sartre indifferent about the Holocaust?
http://www.thejc.com/news/world-news/123919/was-sartre-indifferent-about-holocaust

By Isabel De Bertodano, October 7, 2014

A row has erupted among Jean-Paul Sartre scholars over a new book
which claims that the French philosopher did too little to defend
Jews during the Holocaust.

Ingrid Galster, a German Sartre expert, suggests that not only was
Sartre unsympathetic to the plight of Jews, he actively profited
from antisemitism in France by taking a post at a school when its
Jewish incumbent was removed.

The Sartre scholar Professor Jonathan Judaken at Rhodes College in
Tennessee rebuffed Ms Galster's views.

"He was a critic of all forms of anti-Jewish discourse and
discrimination," he said.

He was hailed as an icon of resistance to Nazism

Mr Judaken, who wrote Jean Paul Sartre and the Jewish Question, said
that Sartre "condemned antisemitism as the ultimate form of bad
faith". He added that evidence could be found in Sartre's plays and
work for resistance newspapers.

In the immediate post-war years, Sartre was hailed as an icon of
resistance, as existentialism became increasingly fashionable. In
1946, he published Antisemite and Jew, an analysis of antisemitism.

However, in Sartre Under the Occupation, Ms Galster suggests that
Sartre felt guilty over his attitude towards the Jews, which
explains why his post-war work appeared more sympathetic.

Dr Eran Dorfman at Tel Aviv University's French Studies department
agreed that Sartre's philosophy "dramatically changed after the war,
to a large extent because he realised what his indifference had led
to, but this does not mean that we should dismiss his intellectual
efforts to respond to the events of the time".

However, Mr Judaken wholly disagreed. "He was utterly
consistent.This was in no way a post-war compensation for his failed
engagement or political commitments during the war."

Sartre himself later remarked that he was more a "writer who
resisted than a resister who wrote," which Mr Judaken said "largely
holds up" as a verdict. However, Mr Judaken conceded that Sartre's
actions under the German occupation of France could invite criticism
- for example, his decision to publish Being and Nothingness with
the Nazi censor's imprimatur. Also, his 1943 play The Flies was put
on in an Aryanised theatre and advertised in the collaborationist
press.

But while "he may not have been a resistance hero who sacrificed
everything", Mr Mr Judaken said, "he clearly condemned Vichy
ideology, fascist intellectuals, and Nazi racism".

Ms Galster's suggestion that Sartre had knowingly benefitted from
the sacking of Henri Dreyfus-Le Foyer from the Lycée Condorcet has
already been disproved, said Mr Judaken, because the post "was
technically turned over first to Ferdinand Alquié before Sartre took
the position".

Ms Galster's views have seen her ousted from "Sartrelogue" circles.

Comment by Jonathan Judaken, Spence L Wilson Chair in the Humanities
at Rhodes College in Tennessee:

The new book by Ingrid Galster, which I have yet to read, sounds the
same drumbeat that she has pounded since at least 2000 when she
wrote an article (followed by a couple of books) that first raised
all of the issues once more ignited by her most recent work.

It is perhaps because she is so unremitting in her claims that she
has annoyed some in the camp of French Sartrelogues. They argue that
she does not provide a balanced judgement on Sartre's position. But
their wholesale defence of Sartre, likewise, does not stand up to
close scrutiny.

I address this debate and argue that "The time has come to situate
Sartre beyond the dichotomies of guilt or innocence, armed
resistance or collaboration" (pg. 51) in my book, Jean-Paul Sartre
and the Jewish Question: http://tinyurl.com/qb6dtjz. The third
chapter of the book goes into great detail, situating what Sartre
said and did with respect to Jews and anti-Semitism under the German
occupation in terms of the ambiguities and ambivalences of life
under the German occupation.

While Sartre was hailed along with Albert Camus as an icon of
resistance in the immediate postwar years, as existentialism became
the intellectual fashion of the day, Sartre later claimed about the
war years that he was more "a writer who resisted than a resistor
who wrote." This self-verdict largely holds up. What he wrote about
Jews and anti-Semitism was clear and consistent, however. He was a
critic of all forms of anti-Jewish discourse and discrimination.

Sartre was way ahead of the curve when it came to actively
critiquing antisemitism and the politics of fascism. This was in no
way a post-war compensation for his failed engagement or political
commitments during the war. Indeed, I have suggested that this was
Sartre's first major engagement and it was one that continued for
the rest of his life.

His longest short story in his collection The Wall, published in
1939, was called "The Childhood of a Leader" and it was a
straightforward, biting critique of a young boy who becomes a member
of the Camelots du roi, the street fighters of the anti-Semitic and
right wing Action Française. Sartre continued to reflect on the
Jewish Question throughout the war years in terms that clearly
anticipated his famous analysis of anti-Semitism published in 1946
and titled in English, Anti-Semite and Jew (Réflexions sur la
question juive).

His stance on the issue was utterly consistent: he condemned
anti-Semitism as the ultimate form of bad faith, a way to avoid
responsibility for our existential freedom. He repeatedly condemned
Vichy ideology and fascist ideologues both covertly in his plays and
explicitly in what he wrote for the underground, resistance
newspapers.

The matter of the position at the Lycée Condorcet that was held by
Henri Dreyfus-Le Foyer before he was removed from the job by the
first anti-Jewish statute, which, contra-Galster, the Sartrean
scholars Jacques Lecarme and Michel Contat established was
technically turned over first to Ferdinand Alquié before Sartre took
the position, is a fact of the matter.

The big question of Sartre's choices under the German occupation
require a very careful contextual examination. Here the wholesale
defence of Sartre by the Sartrelogues has its problems. The claims
about Sartre's careerism and willing complicity to advance himself
even at the cost of collaboration does not hold up. Nor does
Winock's statement that Sartre didn't care about the fate of the
Jews than the majority of French people, as the ink he spilled on
the subject testifies. But Sartre did make choices to publish his
philosophical magnum opus, Being and Nothingness with the Nazi
censor's imprimatur.

His first major play on the French stage, The Flies, was put on in
an Aryanized theater and advertised in the collaborationist press.
He did take the position at the Lycée Condorcet, which had become
available as a result of the purge of Jewish teachers.

I have argued that the kinds of contextually specific judgements
about these kinds of choices that people made during the war and in
its immediate aftermath are actually more nuanced than our
post-Holocaust perspective, which is shaped by not only the clarity
of hindsight, but also a clear sense of right and wrong, good and
evil that we want to believe was apparent in the murkiness of the
period, but alas this was often not the case in the messiness of
fleeting time.

All told, Sartre's claim about himself holds up: he was more "a
writer who resisted than a resister who wrote". In sum, he may not
have been a resistance hero who sacrificed everything in the cause
of denouncing Vichy and fighting against the Nazis. But he clearly
condemned Vichy ideology, fascist intellectuals, and Nazi racism. He
did this during the war and he extended this critique in his postwar
commitments, which when elaborated became some of the most powerful
and influential indictments of racism in all its forms to date.

[tt] Israel National News: Zionist Struggle on Wikipedia

Zionist Struggle on Wikipedia
http://www.israelnationalnews.com/News/News.aspx/138917

A new course teaching how to write Zionist themed entries in
Wikipedia will soon be offered.

By Elad Benari
First Publish: 8/3/2010, 5:16 AM / Last Update: 8/3/2010, 5:08 AM

Wikipedia has become the new battleground for Israel's PR image.

The Yisrael Sheli (My Israel) movement and the Yesha Council, which
represents Jewish communities in Judea and Samaria, have joined
together for a new public relations initiative. Together they will
soon offer a special course for volunteers who wish to write and
edit English entries on Wikipedia, the online encyclopedia.

Ayelet Shaked, who is heading the project, was interviewed on Monday
on Arutz 7 Radio, and said that she was surprised at the large
number of individuals who have gotten in touch with her so far and
are interested in joining the course.

"To our surprise, many applied to attend," said Shaked. "At first we
thought to offer it to only thirty candidates, but now we are
considering opening it to more."

Shaked pointed out that despite the large number of candidates, the
door is still open for other candidates who wish to attend the
course. Explaining the course's goals and methods of operation, she
said: "The goal is to take part in public relations [for Israel] in
English. Wikipedia has rules that one must learn in order to be able
to edit entries. Not anyone can be an editor on Wikipedia. The
information has to be reliable and meet certain rules. Our intention
is to teach these rules as well as show how to deal with different
terminology when writing these entries."

She cited some examples of the Zionist struggle in the use of terms
such as "occupation" in Wikipedia entries, as well as in the editing
of entries that will link between the land of Israel, and
specifically Judea and Samaria, and Jewish history.

Shaked clarified that she does not fear that wealthy leftist
organizations will also take advantage of this opportunity to rise
to the occasion and edit Wikipedia entries based on their own world
views. She noted that such organizations are already operating in
this arena, and added that as far as she is concerned the struggle
should involve more action and less talk. As such she emphasized
that she is not discouraged by any of the concerns described above.
She concluded by once again calling on applicants who wish to
participate in the course to visit the My Israel website and apply
to take part in the first such Wikipedia course which is scheduled
to be held in a few weeks.

According to statistics published on Wikipedia's site, there are
currently 3,367,866 content pages on the site and 12,807,029
registered users, 132,885 of which are active users who are involved
in creating and editing entries.

My Israel is a network of online pro-Israel activists committed to
spreading Zionism online and to counter the spread of lies and
misinformation against Israel which frequently appears on the
Internet. Visit www.myisrael.org.il for more information on the
organization as well as to register for the Wikipedia course.
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[tt] Science Daily: Depression increasing across the United States

Depression increasing across the United States
http://www.sciencedaily.com/releases/2014/09/140930132832.htm

Date: September 30, 2014
Source: San Diego State University
Summary: Americans are more depressed now than they have been in decades, a
recent study shows. Analyzing data from 6.9 million adolescents and
adults from all over the country, researchers found that Americans
now report more psychosomatic symptoms of depression, such as
trouble sleeping and trouble concentrating, than their counterparts
in the 1980s.

A study by San Diego State University psychology professor Jean M.
Twenge shows Americans are more depressed now than they have been in
decades.

Analyzing data from 6.9 million adolescents and adults from all over
the country, Twenge found that Americans now report more
psychosomatic symptoms of depression, such as trouble sleeping and
trouble concentrating, than their counterparts in the 1980s.

"Previous studies found that more people have been treated for
depression in recent years, but that could be due to more awareness
and less stigma," said Twenge, the author of "Generation Me: Why
Today's Young Americans are More Confident, Assertive, Entitled--
and More Miserable than Ever Before." "This study shows an increase
in symptoms most people don't even know are connected to depression,
which suggests adolescents and adults really are suffering more."

Compared to their 1980s counterparts, teens in the 2010s are 38
percent more likely to have trouble remembering, 74 percent more
likely to have trouble sleeping and twice as likely to have seen a
professional for mental health issues. College students surveyed
were 50 percent more likely to say they feel overwhelmed, and adults
were more likely to say their sleep was restless, they had poor
appetite and everything was an effort--all classic psychosomatic
symptoms of depression.

"Despite all of these symptoms, people are not any more likely to
say they are depressed when asked directly, again suggesting that
the rise is not based on people being more willing to admit
depression," said Twenge.

The study also found that the suicide rate for teens decreased,
though the decline was small compared to the increase in symptoms of
depression. With the use of anti-depressant medications doubling
over this time period, Twenge speculates that medication may have
helped those with the most severe problems but has not reduced
increases in other symptoms that, she says, can still cause
significant issues.

Twenge's findings were published in the journal Social Indicators
Research, and an updated and revised edition of "Generation Me" is
being released today.

Story Source:
The above story is based on materials provided by San Diego State
University. Note: Materials may be edited for content and length.

Journal Reference:
1. Jean M. Twenge. Time Period and Birth Cohort Differences in
Depressive Symptoms in the U.S., 1982-2013. Social Indicators
Research, 2014; DOI: 10.1007/s11205-014-0647-1
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[tt] NS 2992: Personal helicopter will be as easy to drive as a car

NS 2992: Personal helicopter will be as easy to drive as a car
http://www.newscientist.com/article/mg22429924.000-personal-helicopter-will-be-as-easy-to-drive-as-a-car.html
* 23 October 2014 by Paul Marks

Within two years, an 18-rotor battery-powered helicopter will be on
sale to rich commuters who dream of open skies instead of gridlocked
highways

AFTER slipping into the pilot's seat, I am handed a sick bag - "just
in case" - and given about 5 minutes of flight instructions. Then,
despite never having flown a plane, I take off vertically in my
futuristic aircraft and explore the UK city of Liverpool from the
air, touching down in the centre circle of the pitch at Anfield,
Liverpool Football Club's stadium.

Sadly, I was only flying in the virtual world at the controls of a
motion flight simulator, which sways and pitches to mimic real
flight - hence the sick bag. But this was a simulator with a
difference: it was running an early version of an easy-to-use
control system that its developers say could form the basis of a
much-maligned concept: the flying car.

Personal air vehicles have a long and chequered history. Cars that
transform into aircraft are the usual approach: another prototype of
this kind will be launched by Aeromobil of Bratislava, Slovakia, at
a technology conference in Vienna next week. But "roadable aircraft"
have failed to take off since the 1950s, not least because they
still need to fly from an airport. They can't replace cars and so do
nothing to ease road congestion, says Heinrich Bülthoff of the Max
Planck Institute for Biological Cybernetics in Tübingen, Germany.
What's needed is a vertical take-off system that can fly point to
point, he says.

That might be closer than it seems. Before the end of the year, a
firm called E-Volo in Karlsruhe, Germany, says it will make its
first piloted flight with an easy-to-fly vertical take-off aircraft
called the Volocopter.

Other enabling technologies are coming together. As part of a EUR4
million pan-European project called MyCopter, researchers have been
developing simple flight control interfaces - one of which is based
on a car steering wheel - plus the cameras and sensors that will let
flying cars automatically avoid each other. They are also working on
flocking software, the software to automatically plot GPS routes and
ways to locate a landing spot in bad weather. They will present
their findings at the MyCopter consortium meeting next month. The
European Commission is funding the project because it sees personal
aircraft as a key part of a future low-congestion transport system.

"At first these vehicles will be for fun with early adopters and for
taxi services," says Bülthoff. "But the main user will be the
commuter who wants to avoid getting stuck in traffic every day."

In late 2013, E-Volo flew a driverless version of the Volocopter,
and Stephan Wolf, one of the company's founders, is confident that
the first piloted model will fly very soon. While it won't be cheap,
it is the kind of technology that will eventually democratise flight
by the mid-2020s, says Bülthoff.

Developed by pilot Mike Jump and his colleague Mark White at the
University of Liverpool, the simulator that I flew simplifies flight
control down to basic up, down, left, right and speed control moves
that anyone can learn in a short time. Or it can fly autonomously
between chosen points. In tests, five volunteers who had never flown
but who could drive cars, mastered the system in around 5 hours.

The Volocopter will be easy to fly, says Wolf, largely because it
avoids the problems caused by a helicopter's massive rotor blades.
This matters because it is learning to cope with the gyroscopic
effect of a regular rotor that makes flying a helicopter so
difficult. It takes hundreds of hours to become a proficient
helicopter pilot.

Instead, the Volocopter has 18 rotors, each 1.8 metres long, that
work in counter-rotating pairs around a circular frame. While it
looks odd, this arrangement means the torque effects of each pair
cancel out and the vehicle just goes up and down, or side to side,
by changing the speed of different rotor pairs.The prototype has
nine lithium-ion battery packs, each driving two motors, that
currently allow it to fly for 20 minutes.

The joystick works in the same way as a quadcopter remote control,
Wolf says. "It's easy to fly even if you have never flown. If you
let go of the stick, the Volocopter just hovers where you left it,"
he says.

City hopper

Unsurprisingly, the regulatory problem remains one of the main
hurdles for personal aircraft. For example, the first two-person
Volocopters - which will be delivered in 2016 for EUR250,000 each -
will be classified and licensed as ultralight aircraft by the German
Federal Aviation Office and will have to fly from airfields under
German law, says Wolf. "But look how driverless cars are rapidly
becoming accepted by regulators and you can see the possibilities,"
he says.

E-Volo has been encouraged by the reaction from municipalities eager
to ease congestion. Megacities like Sao Paulo and Rio de Janeiro,
where rich residents fly helicopters on short hops every day, have
already shown an interest, says Wolf. And the electric flight might
work as a means of lowering carbon emissions, particularly if the
aircraft can be encouraged to fly along particular routes, and so
help reduce congestion.

Andrew Miller, chief technical officer at Thatcham Research in
Newbury, UK, which researches road vehicle technologies for
insurers, says the appeal of a flying car is clear. "The real
selling point will be the increased speed of journeys - that's what
will develop the market," he says.

Alex Tai, director of special projects at Virgin, who pioneers the
group's adoption of new technologies, says he is a strong advocate
of personal flying vehicles. "In time, the advancement of
transportation tech will turn our roads and railways into the
less-used canals of today," he says.

This article appeared in print under the headline "Hop in, I'm
flying"

[tt] NS 2992: Oldest genitals found. Went out of fashion for eons

NS 2992: Oldest genitals found. Went out of fashion for eons
http://www.newscientist.com/article/dn26407-oldest-genitals-found-went-out-of-fashion-for-eons.html
* 18:00 19 October 2014 by Michael Slezak

If you're going through a dry patch, it's nothing compared to the
entire animal kingdom - which appears to have gone millions of years
without copulating. A new analysis of 380-million-year-old fossils
tucked away in boxes in museums is rewriting the textbooks on the
origins of sex and genitalia. It shows genitals started out bony,
were used sideways, and then copulation went out of fashion for tens
of millions of years.

John Long from Flinders University in Adelaide, Australia, and
colleagues have found fossil evidence that one of the earliest jawed
vertebrates called Microbrachius dicki - from a group known as
gnathostomes - reproduced via internal fertilisation. This suggests
that all gnathostomes were doing it too.

The find shows that vertebrates lost and regained the ability to
efficiently deliver sperm internally, many times over. Copulation
was such fun, evolution discovered it again and again.

It also shows that the first jawed vertebrates were copulating. But
close descendants of Microbrachius have been found with clear
evidence showing that they used external fertilisation, Long says.
So the evolution of both external and internal fertilisation must
have happened repeatedly.

"Among the roughly 50,000 species of extant vertebrates, we have no
evidence that internal fertilisation has ever reverted to external
fertilisation," says Daniel Blackburn from Trinity College in
Hartford, Connecticut, who was not involved in the study. "Once a
lineage has evolved a way for males to introduce sperm into the
reproductive tract of the female, they tend to retain that mode of
fertilisation."

Missing, no more

Apparently, not, since Long's work provides this missing evidence,
Blackburn says. "Under this interpretation, internal fertilisation
must have been lost prior to the evolution of the two major lineages
of living jawed fishes." From them evolved the cartilaginous fishes
- modern day sharks, skates, and rays - and the bony fishes and
their descendants - including us.

Around the time the bony fishes and sharks evolved, internal
fertilisation went AWOL, says Long. And then nobody was doing it
until internal fertilisation re-evolved about 20 to 40 million years
later. And when that happened, animals adopted a different way of
locking on to each other.

Long says there are genetic clues as to how the ability could be
lost and then come back. "The HOXD13 gene can develop limbs and
genital organs in mammals and in sharks as well," he says. "Early
fish probably originated the capability of evolving these things and
then they were lost. But once that gene was set in the vertebrate
body plan, it could come back later."

Examining fossil specimens of the earliest known jawed fish, M.
dicki, Long and colleagues found both male and female genitalia that
had gone unnoticed. On the male they found bony structures that
spread out on each side of the fish, with a groove that would have
delivered the sperm. On the female, there were spiny plates that
would have acted like Velcro, holding the male in place.

The real clincher showing that the fish went for internal
fertilisation is that their genitals are nearly identical to those
of later fish, where females have been found complete with embryos,
Long says. "There's no other interpretation of what they could be,"
he says. The new find shows that it was a feature of the very
earliest ones.

It even reveals how they did it (see video, above). "Fundamentally
they couldn't have done it in a missionary position," says Long,
pointing out that the genital structures are bony, immobile and are
on the sides of the fishes. It also explains why the fish have spiny
arms: they were probably used to hold hands, to help lock the
genitals in place, as they did it side-by-side. "We've wondered for
over 100 years what these tiny little jointed arms were used for in
these peculiar fishes," Long says. "The very first act of copulation
was done sideways, square-dance style."

Blackburn, who himself studies reproductive anatomy, says he finds
the analysis of how the genitals were used convincing. "It is most
surprising to find evidence for a loss of internal fertilisation in
a fossil lineage," he says.

Journal Reference: Nature, DOI: 10.1038/nature13825
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[tt] NS 2992: Thoroughly modern humans interbred with Neanderthals

NS 2992: Thoroughly modern humans interbred with Neanderthals
http://www.newscientist.com/article/dn26435-thoroughly-modern-humans-interbred-with-neanderthals.html
* 18:00 22 October 2014 by Michael Slezak

When humans hooked up with Neanderthals, we could have wooed them
with music and fancy jewellery.

The oldest DNA of a modern human ever to be sequenced shows that the
Homo sapiens who interbred with the Neanderthals were very modern -
not just anatomically but with modern behaviour including painting,
modern tools, music and jewellery.

Some previous estimates had placed the first interspecies liaison
much earlier, before the emergence of these features. The new DNA
sequence shows it actually happened in the middle of an age called
the Initial Upper Palaeolithic, when there was an explosion of
modern human culture.

About 2 per cent of many people's genomes today is made up of
Neanderthal DNA, a result of interbreeding between the two species
that can be seen in everyone except people from sub-Saharan Africa.
The so-called Ust'-Ishim man, named after the town in western
Siberia where he was found, carries a similar proportion of
Neanderthal DNA in his genome as present-day Eurasians, and a
combination of radiocarbon and genetic dating shows he died only
about 45,000 years ago.

Before now we couldn't rule out that our fraction of Neanderthal
ancestry was the result of interbreeding between Neanderthals and
modern humans who were in the near east before Neanderthals got
there, says David Reich from Harvard University, a co-author on the
paper. While these near-eastern humans were anatomically modern,
they did not show modern behaviour, he says.

The researchers could work out when Neanderthals first became part
of the man's ancestry by analysing the lengths of the Neanderthal
regions of DNA in his genome. DNA gets chopped up and scrambled over
successive generations, and the lengths in his genome showed that he
was descended a mere 230 to 400 generations from human-Neanderthal
interbreeding between 7000 and 13,000 years before. This pinpoints
the date of our interbreeding with Neanderthals to 50,000 to 60,000
thousand years ago, ruling out almost 50,000 years of previously
possible dates.

"This new paper definitively says it was modern humans with modern
human behaviour that interbred with Neanderthals," Reich says.

"The new timing rules out earlier modern humans in the Middle East
[from participating] in the admixture," says Janet Kelso from the
Max Planck Institute in Leipzig, Germany, one of the lead
researchers on the project.

The Initial Upper Palaeolithic was a period around 50,000 years ago
when complex stone and bone tools appeared across Eurasia, along
with body ornamentation like pierced shells and animal teeth,
pigments and even musical instruments, says team member Tom Higham
of the University of Oxford. It is unknown which human-like species
made these sophisticated artefacts, but the finding that Ust'-Ishim
man was in Siberia at this time means that it could have been modern
humans, he says.

Plotting the family tree

At around 45,000 years old, Ust'-Ishim man is the oldest modern
human ever to have been sequenced. This title was previously held by
a a 24,000 year old boy, also from Siberia, whose DNA was sequenced
last year.

"This is very exciting research that shows again the remarkable
power of ancient DNA analysis to help solve seemingly intractable
questions in human evolution science," says Darren Curnoe from the
University of New South Wales in Sydney, Australia.

By comparing Ust'-Ishim's genome to various groups of modern and
ancient humans, the researchers are filling in gaps in the map of
initial human migrations around the globe. They found that he is as
genetically similar to present-day East Asians as to ancient genomes
found in Western Europe and Siberia, suggesting that the population
he was part of split from the ancestors of both Europeans and East
Asians, prior to their divergence from each other.

"He represents a group that settled Siberia and then disappeared
without leaving descendants," says Curnoe. "This tells us that as
early humans left Africa and settled Eurasia they weren't all
successful. There were more populations than we thought, some making
no contribution to living people at all." He notes this could make
it difficult to interpret human fossils found in Eurasia, since we
cannot assume that they are our ancestors.

But while Ust'-Ishim man does not appear to have any modern-day
direct descendants living today, he is more genetically similar to
present-day East Asians than to present-day Europeans. This finding
is consistent with a recently proposed theory that present-day
Europeans may have got some of their ancestry from later groups that
weren't part of the initial migration into the area. "It supports
that very strongly," says Reich, one of the researchers who
developed the idea.

Irresistible Neanderthals

Homo sapiens is believed to have taken on Neanderthal DNA from at
least two bouts of interbreeding. While sub-Saharan Africans have no
Neanderthal DNA, Asian populations have more than Europeans.

"We know that there are likely to have been at least two admixture
events into the ancestors of present-day people - the shared event
early during modern human migration out of Africa, and a second
event into the ancestors of present-day Asians," says Kelso.

Analysing the lengths of Ust'-Ishim's Neanderthal DNA has pinpointed
the early shared interbreeding event to around 230 to 400
generations before him, but some longer stretches of DNA indicate
that his ancestors had also interbred with Neanderthals even more
recently. "There may have been a later admixture event into the
ancestors of this individual," says Kelso.

Because there are only a few of these longer stretches, they were
unable to precisely date when this later interbreeding may have
happened. But whatever the date, it seems humans and Neanderthals
found each other irresistible, or at least mated with each other
fairly commonly, whenever we inhabited the same areas. "The timing
is most likely simply a result of the fact that this is where the
two groups overlapped geographically and temporally," says Kelso.

Journal reference: Nature, DOI: 10.1038/nature13810
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