16 | New Scientist | 18 April 2020
A PIECE of 50,000-year-old
string found in a cave in France
is the oldest ever discovered.
It suggests that Neanderthals
knew how to twist fibres together
to make cords – and, if so, they
might have been able to craft
ropes, clothes, bags and nets.
“None can be done without
that initial step,” says Bruce Hardy
at Kenyon College in Gambier,
Ohio. “Twisted fibres are a
foundational technology.”
His team has been excavating
the Abri du Maras caves in south-
east France where Neanderthals
lived for long periods. Three
metres below today’s surface,
in a layer that is between 52,
and 41,000 years old, it found
a stone flake, a sharp piece of
rock used as an early stone tool.
Examining the flake under a
microscope revealed that a tiny
piece of string (pictured top right),
just 6 millimetres long and
0.5 millimetres wide, was stuck
to its underside. It was made by
twisting a bundle of fibres in an
anticlockwise direction, known
as an S-twist. Three bundles were
twisted together in a clockwisedirection – a Z-twist – to make
a 3-ply cord (Scientific Reports,
DOI: 10.1038/s41598-020-61839-w).
“It is exactly what you would
see if you picked up a piece of
string today,” says Hardy. The
string wasn’t necessarily used to
attach the stone tool to a handle.
It could have been part of a bag
or net, the team speculates.
The string appears to be made
of bast fibres from the bark of
conifer trees, which helps establish
that it isn’t a stray bit of modern
string, because “nobody at the
site was wearing their coniferpants at the time”, says Hardy.
“It’s so fine. That’s really
surprising,” says Rebecca Wragg
Sykes at the University of Bordeaux
in France. This suggests the string
wasn’t used for heavy-duty tasks,
but instead as some kind of thread,
she says.
Before this find, the oldest
known string came from 19,
years ago. This was discovered in
the Ohalo II site near the Sea of
Galilee, Israel, and is associated
with modern humans. But Hardy
says the newly found string was
made by Neanderthals, as therewere no modern humans in this
part of Europe at this time. This
raises the question of whether
modern humans learned some
of their skills from Neanderthals,
says Wragg Sykes.
Hardy thinks the string shows
that Neanderthals were as smart
as us. They were very similar to
us, says Emma Pomeroy at the
University of Cambridge, whose
team has found evidence that
Neanderthals buried their dead.
“Neanderthals engaged in complex
behaviours that we thought they
weren’t capable of ,” she says. ❚“ It’s obviously bad if
the result is declared
a theorem in some
circles but not others”ArchaeologyMichael Le PageM-H^ MONCE
LNews
Neanderthal string, seen via
a microscope above, was
found at a site in the Abri du
Maras caves in France (left)MathematicsEpic maths proof
to be published
despite major rowAFTER eight years, a mathematician
is finally set to formally publish
a proof that has baffled nearly
everyone who has read it,
including other mathematicians.
In 2012, Shinichi Mochizuki at
Kyoto University in Japan produced
a huge proof claiming to have
solved a long-standing problem
called the ABC conjecture. The
500-page proof was written in
an impenetrable style, and numbertheorists struggled with its ideas.
The work has now been accepted
in the peer-reviewed journal
Publications of the Research
Institute for Mathematical Sciences.
Mochizuki is the editor-in-chief of
the journal, but hasn’t been involved
in the decision to publish the proof,
according to a report in Nature.
The ABC conjecture is based
around the equation a + b = c,
and concerns the link between
the addition and multiplication
of integers, or whole numbers.
Simply put, it says that if a and b
are made up of large powers of
prime numbers – numbers onlydivisible by themselves and one –
then c isn’t usually divisible by large
powers of primes.
Mathematicians have long
believed the conjecture is true,
but nobody had been able to prove
it. Mochizuki grappled with the
conjecture by developing a new
type of mathematics called
inter-universal Teichmüller theory.
In 2018, Peter Scholze at the
University of Bonn and Jakob Stix atGoethe University, both in Germany,
said that they had found a “serious,
unfixable gap” in the proof.
At a press conference on 3 March,
mathematician Akio Tamagawa
said there had been no fundamental
changes in response to the criticism.
“Opinion has definitely shifted
toward the view that the proof
is flawed since the letters from
Scholze and Stix,” says Andrew
Booker at the University of Bristol,
UK. “It’s obviously bad for the
[number theory] community if
the result is declared a theorem
in some circles but not others.” ❚
Donna LuOldest string discovery suggests
Neanderthals wove fibres