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This week’s issue
On the
42 Are we alone?
We can finally answer the
biggest question in the cosmos
30 Selling happiness
How positive thinking
became big business
34 Bad back?
There’s a back pain epidemic.
Most treatments make
things worse.
Here’s why, and what
you can do
6 weeks to go!
Discover our biggest and
best speaker line-up ever
at our 4-day festival of
science. Find out more at
12 Quantum teleportation
Now in 3D!
38 Refreezing the Arctic
Three ways to engineer
the ice cap back
5 Amazon on fire 10 Koala microbiome 17 Spy gliders
14 Pollution and mental health 13 How old is your brain?
Vol 243 No 3245
Cover image: Belovodchenko Anton/Shutterstock
6 Brexit hate speech
The UK government is
using AI to predict spikes in
Brexit-related hate crimes
34 Bad back?
The most common treatments
for chronic back pain may be
making it worse
7 Polio success
Wild polio virus has been
eradicated in Nigeria, but
the battle isn’t over yet
38 Refreezing the Arctic
If we want to save the frozen
north, we may have to bring
the ice back ourselves
20 Dawn of the pyrocene
Arctic wildfires could spur
a powerful feedback loop
42 Are we alone?
After millennia of guesswork,
we can finally start finding out for
certain, says Sarah Rugheimer
The back pages
23 Comment
Genetic medicine tests the
limits of patient confidentiality,
says Laura Spinney
51 Maker
Build a mini weather station
52 Puzzles
Quick crossword, a riddle of ages
and the quiz
24 The columnist
James Wong delves into claims
that fruit is bad for you
53 Feedback
Sexy pavement lichen and a robot
priest: the week in weird
26 Letters
Using biomass to make fuel
is a criminal waste
28 Aperture
Shipping glints from space
30 Culture
The psychology of happiness
feeds a vast industry
8 Coastal erosion Crumbling cliffs prompt communities to retreat
54 Almost the last word
Readers explain why water
hydrates and dogs roll over
56 The Q&A
Niamh Nic Daeid on a paradigm
shift in forensic science
31 August 2019 | New Scientist | 1
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The leader
The climate tipping point
Two crises mean irreversible change is no longer an abstract concept
YOU rock your chair back, confident
you are still in control and can restore
equilibrium. Before you know it, you are
on the floor, struck by an irreversible
change you can’t swing back from.
That’s the dangerous thing about
tipping points: you don’t know you have
reached one until it is too late. Earth’s
climate could now be facing at least two.
Reports from Brazil’s National
Institute for Space Research suggest that
wildfires in the Amazon are occurring
in unusually high numbers (see page 5).
They haven’t yet been confirmed as
record-breaking, but many see them
as evidence that the anti-environment,
pro-agriculture policies of Brazil’s
president, Jair Bolsonaro, are driving
illegal burning of the rainforest.
This is disastrous for the people and
wildlife living there, and for the planet.
The policies of
Brazil’s president,
Jair Bolsonaro,
have seen an
increase in
Amazon burning
The Amazon is a region of extraordinary
cultural and biological diversity, and
a huge global sink of carbon dioxide.
We need it to have a chance of keeping
global warming to a manageable level.
Fewer trees means less water vapour
being pumped into the atmosphere.
Intact regions of forest start to suffer.
At some point, the whole may reach
a tipping point where the untouched
forest dies and the Amazon flips to
become a non-forest ecosystem.
We don’t know where that point is.
Some studies indicate that we could
get there if a fifth of the rainforest is
lost. Others suggest a tipping point
could be reached as soon as 2030.
Meanwhile, an unprecedented
number of fires are ripping through the
Arctic (see page 20). There, the tipping
point is of a different nature: a sea-icefree Arctic creating positive feedbacks
that accelerate warming. That risk is now
so dire that some researchers say we
should investigate local geoengineering
options to prevent it (see page 38).
The law of unintended consequences
means that must be a last resort. As
for the Amazon, Bolsonaro must be
persuaded to about-face, if necessary
by withholding aid and trade deals.
We know by now what we all have to
do. Let’s not test the tipping points. ❚
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31 August 2019 | New Scientist | 3
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Managed retreat
The fight to save
coastal dwellings
from rising seas p8
Digital privacy
Facebook’s data may
put millions of gay
people at risk p11
Shock waves in space
LIGO spots its first
black hole-neutron
star collision p13
Air pollution
Is city air causing
mental health
conditions? p14
Birds and burgers
Crows may have high
cholesterol because
they eat fast food p7
Amazon fires are on the rise
Fires raging across the Amazon have renewed efforts from some countries, companies
and individuals to protect the rainforest. Michael Le Page and Adam Vaughan report
A LARGE increase in the number of
fires in the Amazon rainforest has
led to an international outcry and
a row over the need for action.
Brazilian president Jair
Bolsonaro has rejected an offer
of $22 million from seven of the
world’s richest countries to help
tackle the fires, accusing the G7
of colonialism and suggesting the
money be used to reforest Europe
instead. Many environmentalists
also criticised the offer, saying it
was too small.
Despite Brazil’s rejection of the
offer, more money should reach
non-governmental organisations
trying to save the Amazon
rainforest thanks to private
fundraising efforts by individuals
and companies. Leonardo
DiCaprio pledged $5 million, for
instance, and Apple said it would
donate an undisclosed sum.
On Tuesday, the European Space
Agency (ESA) said its satellites had
detected nearly four times as
many fires burning over the past
few weeks compared with the
same period last year: 4000 from
1 to 24 August versus 1100 last year.
There are fires burning in parts
of Peru, Bolivia, Paraguay and
Argentina as well as Brazil.
While wildfires do occur
naturally during Brazil’s dry
season, almost all the fires are
thought to have been deliberately
started with the intent of clearing
the land.
Last week, the ESA said the
carbon dioxide released by the
blazes in August was the highest
for the month since 2003. The fires
have also been releasing carbon
monoxide, and thick smoke has
reached cities such as Sao Paolo.
“The past week has been really
concerning in terms of the
Amazon forest, there is no
question about it,” says Erika
Berenguer at the University of
Oxford. Saving the Amazon is
seen as crucial to efforts to limit
global warming and preserve
The latest on the Amazon online
For more on the race to save the rainforest visit
biodiversity. The rainforest stores
vast amounts of carbon and hosts
a rich variety of species.
The Amazon is also home to
400 groups of indigenous peoples.
These peoples say they are being
subjected to a rising number of
attacks. “But these crimes go
unpunished; they are increasingly
encouraged by our national
leaders, including the President
of Brazil,” Sonia Guajajara,
coordinator of the Association of
Indigenous Peoples of Brazil, said
in a statement. “We are putting
our bodies and our lives on the
line. If we disappear, so will the
world’s tropical forests.” ❚
To learn about tackling a world
of wildfires, see page 20
31 August 2019 | New Scientist | 5
Social media
Predicting Brexit-related hate crimes
As the UK’s exit from the EU nears, government agencies are trying
to pinpoint hotspots of race-related hate speech, reports Donna Lu
Reported hate crimes
spiked after the UK voted
to leave the EU in 2016
6 | New Scientist | 31 August 2019
The team recently established
for the first time that an increase
in hate speech on Twitter leads
to a corresponding increase
in crimes against minorities
on London streets (British
Journal of Criminology,
doi.org/c9qh). The pattern is
similar to what happens with
domestic violence, which
often escalates from verbal to
physical abuse, says Williams.
The team found that as the
number of tweets that were
antagonistic about race, ethnicity
or religion increased, so did the
incidence of aggravated crimes,
including violence, harassment
and criminal damage. A similar
study in 2018 found a link between
the number of anti-refugee
statements on Facebook and
violent crimes against refugees
in Germany.
Relevant government
authorities such as police
THE UK police are monitoring
hundreds of thousands of Twitter
posts containing hate speech
every day. It is part of a pilot
project to predict spikes in hate
crimes in the run up to 31 October,
when the UK is due to leave the
European Union.
The Online Hate Speech
Dashboard is being used by
analysts at the National Police
Chiefs’ Council’s online hate
crime hub, which was established
by the Home Office in 2017 to
“tackle the emerging threat
of online hate crime”.
It gathers Twitter posts from
across the UK and uses artificially
intelligent algorithms to detect
speech that is, for example,
Islamophobic, anti-Semitic or
directed against people from
certain countries or with
disabilities or from LGBT+ groups.
The police chiefs’ council tasked
Matthew Williams at Cardiff
University, UK, and his colleagues
with developing the dashboard so
that government organisations
could monitor hate speech.
The dashboard flags between
500,000 and 800,000 tweets
per day as containing hate-related
language. About 0.5 per cent
of these are from users tagged
with precise locations within
the UK, which the dashboard
presents as a map of hate
hotspots. If there is a spike, the
information can be passed by
analysts to the relevant local
police forces, says Williams.
Previously, such monitoring
had to be done manually.
The main aim of the project is to
identify patterns of hate speech in
the lead up to 31 October to warn
police and support organisations
of any potential issues.
forces and councils may use
the information from the hub
for counter-messaging on social
media. These include awareness
campaigns, reiterating zero
tolerance for hate crimes and
encouraging people to report
incidents to True Vision, a national
crime reporting hub.
Last year, the UK government
launched a nationwide hate crime
“The dashboard flags
between 500,000 and
800,000 hate-related
tweets per day”
awareness campaign, which
included adverts on social media.
The hope is that the dashboard
will lead to a reduction in
online hate speech. It includes
information about the trends
in hate speech against each group
over time, and commonly used
words and hashtags in hateful
tweets. In addition, it shows
networks of tweeters who interact
with each other, although their
identities are anonymised. These
clusters can provide information
about how much of the hate
speech results from coordinated
efforts, says Williams.
Williams and his colleagues
measure the performance of the
dashboard using an F1 score, a
statistical measure of accuracy
that takes into account the rate of
true and false positives. “Usually,
our algorithms come in between
85 and 95 per cent,” says Williams.
Less than half of hate crimes
are reported to the police.
According to the Crime Survey
for England and Wales, racially
and religiously motivated crimes
in the two nations spiked after the
Brexit vote in 2016, with 5605
crimes reported in July that year,
up 44 per cent from the same
period in 2015.
People with racist views feel
emboldened to target others
by events like the vote, says
Imran Awan at Birmingham
City University, UK.
The police are often slow in
reacting, he says. Awan attributes
this to scepticism about the link
between online and offline abuse.
“The perception is: ‘Do I really
need to come out and speak to
somebody because they’ve posted
a tweet?’.”
Hate-speech detection tools
that analyse aggregated data may
not be able to prevent individual
acts of violence, says Timothy
Quinn at Hatebase, a firm that
provides hate speech resources
to law enforcement agencies.
Such tools are more useful for
governments to identify overall
rises in hate speech across a
region, giving opportunities
to prevent it escalating into
violence in the form of riots,
for example, he says. ❚
Analysis Polio
City crows may have
high cholesterol
thanks to fast food
Wild polio virus eradicated in
Nigeria, but battle isn’t over yet
Jake Buehler
Debora MacKenzie
The oral polio vaccine
has helped wipe out
wild polio in Nigeria
CROWS living in urban areas have
higher blood cholesterol levels than
their rural counterparts. That may
be due to the food we leave behind
for them to feast on.
Crows are “experts at raiding
human trash cans and dumpsters”,
says Andrea Townsend at Hamilton
College in New York. Some of the
food they scavenge is fast food,
which is often high in cholesterol.
Townsend and her colleagues
measured cholesterol levels in
blood samples taken from
140 American crow (Corvus
brachyrhynchos) nestlings in
rural, suburban and urban areas in
California. They also measured the
birds’ body mass and fat reserves,
and tracked their survival rates.
They found that the more urban the
surroundings, the higher the blood
cholesterol of the crow nestlings.
To see if access to the foods
that raise cholesterol in
humans were responsible, the
researchers ran a “cheeseburger
supplementation experiment”
where they left cheeseburgers
near nests in rural New York.
Townsend didn’t have
reservations about leaving behind
burgers for the nestlings as elevated
cholesterol doesn’t appear to
affect all species in the same way,
and has actually been linked to
better body conditions in some
animals, she says.
The burger-fed rural crows had
cholesterol levels that were about
5 per cent higher than nearby crows
that weren’t given fast food. Those
that ate the burgers had cholesterol
levels more similar to crows living
in cities (The Condor: Ornithological
Applications, doi.org/c9r9).
Townsend says these results are
consistent with the handful of other
studies on cholesterol in animals
that live near humans, including
foxes, sparrows and even sea turtles
living near more densely populated
Canary Islands. ❚
NIGERIA has officially wiped
out wild polio, after three years
without a case caused by the
wild polio virus. This is a
heartening milestone for a
country that nearly derailed
the global drive to eradicate
the disease after some regions
banned vaccination in 2003.
But Faisal Shuaib, head of the
country’s public health agency,
called for “cautious euphoria”.
That’s because Nigeria hasn’t
wiped out polio. As first revealed
by New Scientist in 2000, the
live, weakened polio virus used
in the vaccine responsible for
the breakthrough can spread
between people and mutate to
a form that can paralyse. It has
caused 15 cases of vaccinederived virus infection in
Nigeria so far this year.
There are ways to stop this
happening, but they haven’t
been rolled out fast enough,
says Michel Zaffran, head of
polio eradication at the World
Health Organization.
The drive to eradicate polio
was based on a cheap, effective
oral vaccine containing
three strains of live, weakened
polio virus. The Type 2 strain
replicated faster than the others,
provoking the most immunity.
As a result, wild Type 2 polio has
been eradicated worldwide
since 1999.
The Type 2 vaccine virus is
also the strain most likely to
mutate to a disease-causing
form. In 2018, there were
70 cases of vaccine-derived
polio in seven countries, the
majority Type 2 viruses. So in
2016, everyone shifted to using
“In 2018, there
were 70 cases of
vaccine-derived polio
in seven countries”
a live oral vaccine containing
only Types 1 and 3. Immunity to
those improved, and cases fell.
At the same time, children
were supposed to get an injected
vaccine containing killed
versions of all three strains of
virus, making them immune to
any vaccine-derived virus still
circulating. In this way, India
eradicated all polio in 2014.
But too few children in
poorer nations get routine
vaccinations, so “there have
been more outbreaks of Type 2
vaccine-derived virus than we
expected”, says Zaffran.
The only way to stop such
an outbreak spreading is to
give people a live, oral vaccine
containing only weakened
Type 2. This is because while the
injected vaccine will stop people
getting infected, once they are
infected only the live vaccine
will stop them spreading the
virus. In an outbreak, 95 per cent
or more of people infected don’t
have symptoms but spread the
virus, so many people must
be vaccinated.
But the live, Type 2 vaccine
also spawns yet more
potentially dangerous vaccinederived virus, which can go on
to cause more infections if it
encounters children who
haven’t been immunised
against Type 2 with the injected
vaccine. Routine vaccination
must improve alongside
outbreak response, but that is a
slow, expensive process and is
hampered in many places by
unrest or conflict, including in
northern Nigeria.
That’s not the only problem.
Only three companies make the
live, Type 2 vaccine, so we could
run out. “We have enough to
cope now, but there could be
a crisis if the outbreaks don’t
improve,” says Zaffran.
Yet there are ever more
people susceptible to vaccinederived Type 2 polio, as wild
polio no longer circulates and
immunises people, and too few
receive the injected vaccine.
Polio could roar back worse
than ever if it isn’t contained,
says Zaffran. ❚
31 August 2019 | New Scientist | 7
Fieldnotes East Anglia, UK
JANE HAMILTON stands next to
a model of Dunwich in Suffolk,
UK, the “lost city” that was once
one of England’s largest ports, but
has been largely swallowed by the
sea after storms in the 13th and
14th century and years of erosion.
She accepts that people will have
to retreat in the face of a warming
world and rising seas. “It’s natural.
It’s like people dying, it does
happen,” she says.
As a resident of the remaining
village, that doesn’t mean she
wants to stand back and let it
happen. “It’s human nature
to preserve your community,” says
Hamilton. “I don’t accept: ‘That’s
fine, it’s all going to fall in the sea,
we’ll all move inland.’ ”
Dunwich is one of several
communities in East Anglia, an
area on England’s east coast, that
must decide whether to promote
a “managed retreat” inland or to
hold the line. In a recent article in
Science, researchers argued that
adaptation to climate change
means, in some places, “the
“It’s human nature to
preserve your community.
I don’t accept: ‘That’s fine,
it’s going to fall in the sea’ ”
question is no longer if retreat will
occur but how, where, and why”.
The UN’s Intergovernmental
Panel on Climate Change predicts
warming will bring a sea level rise
of up to a metre by 2100, and more
if the Antarctic ice sheet begins its
collapse this century. In England,
the Environment Agency (EA) has
said sea level rise can’t be fought
with “limitlessly high walls and
barriers” alone.
Juliet Blaxland, who lives a
few kilometres up the coast from
Dunwich near the crumbling cliffs
of Easton Bavents, recognises the
need to adapt. “In nature, the
most successful animals are
8 | New Scientist | 31 August 2019
Moving away from the coast Rising sea levels mean that
a managed retreat for coastal communities is no longer a
case of if, but when and how. Adam Vaughan reports
not necessarily the biggest and
fastest, but the most adaptable
to change,” she says. Historically,
around a metre of coast was lost
each year here, but recently, it has
been around 3 metres annually,
she says.
While Blaxland accepts that her
home probably has just a few more
years left, neighbouring buildings
reveal contrasting attitudes
towards coastal erosion. One is
the former house of Peter Boggis,
dubbed King Canute for building
his own coastal defences by the
cliffs, in defiance of authorities.
Down the road, a pair of holiday
homes, the Watch Houses, were
built with steel frames so they can
be easily moved inland by crane.
In the past, the UK government
offered money to help people
relocate, as well as assisting with
planning issues around new
homes for them, but no such
schemes are active today.
“We are very much responding
to the climate emergency,” says
Julie Foley of the EA. Its policy is
to defend the majority of
England’s coastline, and moving
people in response to climate
change is the exception, she says.
The EA recently finished the
£70 million Ipswich Tidal Barrier
in Suffolk, a large “hold the line”
defence. More hardware and
engineering like this will be needed
in the region, says Mark Johnson
of the EA, such as an increase in
the height of beaches in Norfolk to
help protect Bacton Gas Terminal.
David Ritchie of East Suffolk
Council says managed retreat
can be positive, pointing to the
Benacre Estate, just north of
Easton Bavents, where there
are plans to flood 100 hectares
with seawater to create an
intertidal habitat.
In Shotley, near Ipswich,
Richard Wrinch stands on
the doorstep of his farmhouse,
overlooking a glorious vista of
fields bordering the river Orwell
that flooded during a 2013 storm
surge. The farmer has been talking
with the EA and others for more
More climate change online
For more on our warming planet
Coasts are in retreat across
East Anglia, including here
at Happisburgh in Norfolk
than a decade about giving up
land to the sea. “I have no direct
problem with a managed retreat,
because that’s what humanity has
done for millennia,” says Wrinch.
What is missing is clarity from
authorities, he says.
A glimpse of a possible future
for Wrinch lies across the county
border in Essex. At Fingringhoe
Wick nature reserve, the sea wall
was deliberately breached in
2015, so seawater now covers
22 hectares of former farmland.
Mark Iley of the Essex Wildlife
Trust, which worked with the EA
on the scheme, says losing hardwon land is “very controversial”,
but that the project has been a
roaring success for both human
and avian visitors.
The motivation was to create
salt marsh habitat, which is fast
disappearing throughout England.
However, the approach could
be applied elsewhere if the two
challenges – finding funding and
willing landowners – are overcome,
says Merle Leeds of the EA. ❚
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Koala microbiome shift
Faecal transplants help the marsupials change their diets
KOALAS in Australia may find
settling into a new habitat easier
after a faecal transplant.
In 2013, a population of koalas
grew so large that the animals ate
enough leaves from their preferred
type of eucalyptus tree, the manna
gum (Eucalyptus viminalis) to kill
many of the trees. This resulted in
starvation and the death of more
than 70 per cent of the koalas.
Surviving animals were moved
to a new area, but they had little
interest in feeding on a similar
tree, the messmate (Eucalyptus
obliqua), despite other koalas
living off it exclusively.
Michaela Blyton at the University
of Queensland, Australia, found that
giving the relocated koalas a faecal
transplant from the local population
helped them to adapt. The process
changed the koalas’ natural mix
of bacteria, which began to
resemble that of the donors (Animal
Microbiome, doi.org/c9nx). ❚
Ruby Prosser Scully
LIGO could solve space expansion mystery
COSMOLOGISTS can’t agree on
how fast the universe is expanding
because the two methods they use
to find out give distinctly different
results. Now a third method
involving gravitational waves
could help break the deadlock.
Gravitational waves are the
ripples in space-time whose
existence was confirmed in 2015
by the Laser Interferometer
Gravitational-Wave Observatory
(LIGO). They are produced when
massive objects like black holes
or neutron stars smash together
(more on page 13).
To calculate the Hubble constant,
which quantifies the expansion
rate of the universe, astronomers
usually look at distant objects and
10 | New Scientist | 31 August 2019
find out two things: how far away
they are and their redshift, which
is the degree to which the object’s
light has stretched as it passed
through expanding space on its
way towards us.
The Hubble constant is usually
calculated either by looking at
certain supernovae or at the
cosmic microwave background,
often called the big bang’s
afterglow. But these methods
result in different numbers.
It is possible that this discrepancy
is caused by errors, but some
astronomers believe that it is
evidence of unknown physics.
The events that make
gravitational waves don’t always
produce light. Even if they do, it
can be hard to spot. But in 2017,
LIGO researchers showed that if
they could catch some light from
the source of a gravitational wave,
they could measure the redshift.
The gravitational wave itself gives
the distance, so the Hubble
constant could be calculated.
“The two methods we
use to find out how fast the
universe is expanding give
distinctly different results”
Now the LIGO team has
extended its work to black hole
mergers, which don’t emit light.
The group instead used galaxy
catalogues to identify the most
likely place that the gravitational
waves came from. Then they
used the galaxy’s redshift in
their calculations (arxiv.org/
The new method is important
because it is independent of
the other two, but it can’t yet
provide a definitive answer. The
10 detections made so far are too
few to provide a precise estimate
of the constant.
“At the moment, our method
is like Switzerland, completely
neutral,” says Patricia Schmidt
at the University of Birmingham,
UK, and a member of the LIGO
consortium. As more detections
are made, the estimate should
get more precise. ❚
Stuart Clark
Data privacy
Revealing why posts
are moderated helps
us comply with rules
Facebook’s data collection
may put gay people at risk
Chris Stokel-Walker
Chris Stokel-Walker
SOCIAL media platforms struggling
to tackle the tide of misinformation
and unsuitable content could cut
its flow by a fifth by better
explaining their rules. That is
the finding of a large-scale study
of 32 million posts on popular
discussion site Reddit.
On Reddit, volunteer moderators
clear forums, called subreddits,
of unsuitable or off-topic material.
Moderators take different
approaches, however. Some explain
why they have removed the content,
but about 99 per cent simply take it
down without explanation. Shagun
Jhaver at the Georgia Institute of
Technology and his colleagues have
found that those who have had their
posts removed – with or without
explanation – are less likely to
continue posting. But those who
aren’t provided with a reason why
their content was taken down have
a higher likelihood of further posts
being removed than those who are
given an explanation.
Another study by the team found
that 37 per cent of Reddit users
surveyed didn’t understand why
their post was removed, and 29 per
cent felt frustrated that it had been.
The group calculated that if all
post removals were accompanied
with an explanation, the odds of
future removals would drop by
20.8 per cent. The team will present
the work at the Conference on
Computer-Supported Cooperative
Work and Social Computing in
Texas in November.
While the system works in small
communities, it may be hard to
scale across a larger site such as
YouTube, which has been criticised
for its opaque rules on what is
acceptable content.
“Moderators have to be careful
about how they articulate their
policies,” says Kat Lo at the
University of California, Irvine.
“It has to be able to move between
many different types of context.” ❚
MILLIONS of gay people
living in countries where
homosexuality is outlawed
could be put at risk by
Facebook’s advertising
practices. This is because the
firm allows advertisers to target
people on the basis of their
interests, including sexual ones.
Ángel Cuevas Rumín at
Charles III University of Madrid,
Spain, and his colleagues
analysed the list of options
available for targeting adverts
on Facebook. They found that
about 2000 of the options
would be classed as “sensitive”
information under Europe’s
recent GDPR data protection
law. These include a person’s
politics, race or sexuality.
Some two-thirds of Facebook
users in the 197 countries and
states the team looked at were
tagged with at least one such
preference, accounting for a
fifth of the overall population.
In Saudi Arabia, where
homosexuality can be punished
with death, the team found in
February that 540,000 people
were labelled as having an
interest in homosexuality.
The team revisited that number
in August and it had nearly
doubled to 940,000 people.
Overall, Cuevas’s team found
that there were more than
practice, such information
could be used to identify people
and collect information on
them. For example, an advert
directed at a particular group
could offer a prize to people if
they enter their personal details.
Facebook says that just
because someone shows an
interest in something doesn’t
mean they have that attribute.
You could like a page about gay
men, for example, without
being a gay man yourself.
people in Saudi Arabia are labelled However, there is likely to be
as interested in homosexuality
overlap between the two groups.
“The interest targeting
4.2 million people tagged as
options we allow in ads reflect
interested in homosexuality
people’s interest in topics, not
living in countries where
personal attributes,” Facebook
homosexuality is illegal.
told New Scientist. “People can’t
These people could be targeted
discriminate by excluding
using Facebook’s ad tools (arxiv. interests such as homosexuality
when they build an ad.” The firm
While there is no suggestion
says it recently removed more
that anyone has been identified than 5000 targeting options.
or killed as a result of this
Collecting such data is a legal
grey area. In Europe, there are
stronger legal protections for
sensitive data than there are for
other types of personal data.
However, data protection
experts are torn over whether
Facebook is breaking any laws.
“Facebook is in the wrong for
sure, as far as EU data protection
law is concerned,” says Ed Boal
at Stephenson Law in Bristol,
UK. Sandra Wachter at the
Oxford Internet Institute, UK,
isn’t so sure. “If the argument
being made is nobody is
inferring sexual orientation but
assuming an interest in sexual
orientation, that brings us to an
unclear legal perspective,” she
says. “We need to broaden data
protection in a more sensible
and holistic way.” ❚
If you “Like” a Facebook
page, the data is used
to record your interests
31 August 2019 | New Scientist | 11
Quantum teleportation win
QUANTUM teleportation has
made a leap in sophistication.
Physicists have teleported more
information at once than has
ever previously been possible,
paving the way for a global
quantum internet that would be
extremely secure from hacking.
This isn’t teleportation as you
might imagine it from science
fiction. Rather than transporting
matter through space, it involves
moving information related to
the quantum state of a particle.
Previously, we have only been
able to teleport quantum bits,
or qubits, the simplest unit of
quantum information in which
a particle can be in two states
at once. For instance, a photon
that is simultaneously vertically
and horizontally polarised would
be a qubit.
Now Jian-Wei Pan at the
University of Science and
Technology of China and Anton
Zeilinger at the University of
Vienna in Austria and their
colleagues have teleported a more
complicated unit of quantum
information called a qutrit for
the first time. If a qubit can be
considered two-dimensional,
a qutrit is three-dimensional:
the photon is polarised in three
perpendicular directions.
“The higher the dimensions
of your quantum system, the
more secure you can ensure your
communication is and the more
information you can encode,” says
Ciarán Lee at University College
London. “But going from a qubit
to a qutrit is especially difficult:
the tricks you use for qubits have
to do with a nice symmetry that
qutrits don’t have.”
To teleport a qubit, you begin
with three particles. One is the
qubit whose information you
want to teleport. The other two
are a pair of particles that have
been entangled in such a way
12 | New Scientist | 31 August 2019
Physicists have used the rules of quantum entanglement to teleport
a richer package of information than ever before, reports Leah Crane
that making a measurement
on one will affect the result of a
measurement made on the other.
Now imagine two people,
traditionally called Alice and Bob.
Alice has the qubit and one of the
pair of entangled particles. Bob
has the other particle in the pair.
If Alice wants to send the qubit’s
“Passing messages through
quantum entanglement
would be a very secure
means of encryption”
information to Bob, she performs
a special kind of measurement
on both her particle and the
qubit. Going through this process
means that Alice’s particle is now
entangled with the qubit, as well
as Bob’s particle.
Because of all this entanglement,
Alice’s measurement forces Bob’s
particle into one of four possible
states. He can find out which by
making a measurement. The
results of Alice’s measurement –
which she can send to Bob using
non-quantum methods, such as
an email – lets him determine how
the measured state of his particle
is related to that of the original
qubit. Once he knows that, he can
reconstruct the information from
the original qubit. Its information
has been teleported.
Qutrits are a level up in
difficulty because it is much
harder for Alice to perform her
measurement and entangle her
particle with the qutrit.
The researchers got around this
by adding another particle to the
system so Alice is measuring three
particles instead of two (Physical
Review Letters, doi.org/c9ns).
As a result, her measurements
contain more information, which
she sends to Bob, allowing him to
reconstruct the qutrit.
The researchers could teleport
qutrits with 75 per cent fidelity,
meaning Bob’s qutrit was 75 per
cent similar to Alice’s original.
That may not seem high,
Love quantum theory?
More entanglement and weirdness online
Teleportation depends
on spooky quantum
but the highest fidelity possible if
the quantum entanglement had
failed is 50 per cent.
“Seventy-five per cent is
probably not good enough to
start communicating in this
way with much accuracy, but
this is early days,” says Lee.
The researchers claim that
their method could be used to
teleport even larger packets of
information with higher fidelity.
If that works out, it would be
a further step towards quantum
communication systems. Passing
messages using quantum
entanglement would be far
more secure than current
encryption methods.
Quantum teleportation
could enable information to
be passed over long distances
by secure quantum networks,
says Lee. “The ability to teleport
a high-dimensional system is
going to be one of the bedrocks
on which a future quantum
internet is built.” ❚
Tests at 3 years old could predict
brain ageing in later life
Jessica Hamzelou
things like cholesterol and blood
sugar levels to estimate the
biological age of the volunteers’
bodies. They found that this was
loosely linked to brain age, but not
totally. “There are some people
who have a very advanced brain
age whose bodies seem to be
ageing slowly, and vice versa,” says
Elliott. However, the team found
that those who had the highest
scores on cognitive tests when
Lower stress levels and
exercise may help your
brain stay young
they were 3 years old went on to
have the youngest-looking brains
(bioRxiv, doi.org/c9ng).
This suggests we might be able
to tell who is at risk of accelerated
brain ageing early in life, says
Elliott. He hopes that predicting
brain ageing earlier in life could
allow treatments for conditions
like dementia to be started sooner.
This means they might have a
better chance of working.
James Cole at King’s College
London cautions that it will be
difficult to make predictions
based on a 3-year-old’s test results.
“Acceleration or delay could be
positive or negative,” says Cole.
“If a 60-year-old has a brain that
looks 70, that’s bad, but if a 3-yearold has a brain that looks 5, that
might be a good thing.”
The team also asked other
researchers to guess how old the
volunteers were based on photos
of their faces. Again, the responses
varied hugely, with estimates
coming in 20 years above and
below their actual age. Those who
looked older also had older brain
ages. “It suggests that the outward
signs of ageing are reflected by the
internal signs of ageing,” says Cole.
That doesn’t mean that all olderlooking individuals will be on
their way to dementia, says Elliott.
We don’t yet have a way to treat
brain ageing, but given the known
benefits to the brain of healthy
eating and exercise, these aren’t
a bad place to start. “Ageing is a
complex interaction of genes
and environment,” says Cole.
“The environmental factors are
likely to be things like stress levels,
diet, how much physical exercise
people get and how much they
use their brains,” he says. ❚
they had seen their first black hole
and neutron star merger, only for the
observation to be chalked off due to
the high possibility the signal was
background noise from Earth. This
time, researchers are almost certain
the signal came from beyond Earth.
Researchers around the globe
are now running the numbers to
confirm the identity of the two
objects involved. Given its size,
researchers agree the larger
is a black hole. Based on initial
estimates of its mass, the smaller is
probably a neutron star. “But there
is the remote possibility it could
actually be a very light black hole,”
says Scott. If that proves to be the
case, it would be by far the lightest
black hole ever observed. “We have
to look at the signal to see if we can
confirm it is behaving like a neutron
star in the in-spiral,” says Scott.
Ticking off the final of the three
types of event doesn’t mean LIGO
will be powered down, however.
“That’s just the end of the
beginning,” says Scott. ❚
James Mitchell Crow
YOUR brain isn’t necessarily the
same age as the rest of you. Now,
it may be possible to predict how
quickly a person’s brain will age
throughout life based on tests
taken when they are 3 years old.
A person’s biological age may
be a better indicator of their health
than their chronological age. Brain
age can be measured using brain
scans and machine learning to
determine if a person’s brain looks
older or younger than the average
healthy brain for people of the
same age.
To find out if brain age might
reveal anything about a person’s
health in midlife, Max Elliott at
Duke University in North Carolina
and his colleagues assessed the
brains of 869 adults in New
Zealand who have undergone
regular medical and cognitive
testing since they were 3 years old.
When the volunteers, all aged
between 43 and 46, underwent
MRI brain scans, the team found
that their brain ages ranged from
23 to 71. Those with older brain
ages performed worse on tests
of cognition, memory and IQ.
The researchers also measured
A black hole has
been seen eating
a neutron star
ALMOST 900 million years ago,
two objects – one a black hole, the
other almost certainly a neutron
star – slammed together with
incredible force, sending shock
waves through space-time.
These gravitational waves
have now washed over Earth.
Last week, scientists from the Laser
Interferometer Gravitational-Wave
Observatory said the waves were
picked up by LIGO’s detectors in the
US and by Italy’s Virgo detector.
“We’re very confident that
we’ve just detected a black hole
gobbling up a neutron star,” says
Susan Scott, a theoretical physicist
at the Australian National University
in Canberra and part of the LIGO
If confirmed, the observation
would complete the trifecta of
cataclysmic events researchers had
hoped to detect when LIGO was first
proposed: the collision of two black
holes; the collision of neutron stars
in a binary system; and the merger
of a black hole and a neutron star.
In April, LIGO researchers thought
900 m
Approximate number of years
since the collision spotted by LIGO
31 August 2019 | New Scientist | 13
Briefing Mental health
Earth science
Why is pollution linked to
schizophrenia and depression?
Volcano that
led to little ice
age identified
Chris Baraniuk
What has the latest study found?
Analysing data from 151 million
people in the US and 1.4 million
people in Denmark, researchers
discovered a strong correlation
between poor air quality and
higher rates of bipolar disorder,
schizophrenia, personality
disorders and major depression
(PLoS Biology, doi.org/gf6t7f).
This suggests there is a link, but
not necessarily that pollution is
causing these conditions.
How strong is the link?
When the researchers looked
at health insurance claims in
the US, they found that the
strongest predictor of being
diagnosed with bipolar disorder
(after ethnicity) was air quality.
Previous studies have
unearthed a correlation in
the UK between polluted
areas and teenagers reporting
psychotic experiences, and local
air pollution and psychiatric
disorders in Swedish children.
How good is the evidence?
“We don’t really know very
much overall. We’ve only got
a handful of studies and most
have methodological problems,”
says Helen Fisher of King’s
College London, who worked
on the UK teenager study.
One problem is a lack of data
on what an individual’s true
exposure to air pollution has
been, with some research
looking at city-wide air quality
A NEW study has added to the
mounting evidence suggesting
air pollution is linked to mental
health conditions. But it isn’t
clear yet how – or if – pollution
may be affecting our brains.
Busy traffic in
Copenhagen, Denmark
measurements rather than
specific addresses. That is a big
weakness, given we know air
pollution exposure can vary
significantly from one street
to the next. In the new study,
exposure in the US was mapped
at county level, administrative
areas that can cover thousands
of square kilometres.
What else could explain the
associations between dirty air
and psychiatric conditions?
The study tried to take into
account confounding factors
where figures were available,
including income, ethnicity
and population density. But an
obvious factor that could be
linked to both mental health
and pollution is traffic noise.
This is known to increase stress
and disrupt sleep, which are
both linked to mental ill health.
In what ways could pollution
affect our brains?
Some of the smallest pollution
More mental health news online
The latest research on depression and other conditions
14 | New Scientist | 31 August 2019
particles can pass through the
blood-brain barrier, potentially
affecting the brain. Air pollution
is known to cause inflammation
in the body, which may ignite
the brain’s stress response. Or
perhaps pollution can cause
epigenetic changes that affect
the levels of signalling chemicals
in the brain. But these are only
tentative ideas.
“Air quality was a
strong predictor of
being diagnosed with
bipolar disorder”
Why does it matter if air quality
affects our brains? Shouldn’t
we care because of the known
physical effects it has anyway?
Stronger evidence of a link to
mental health might not have a
huge impact on policy because
the case for action on air
pollution – such as it shortening
lives through lung and heart
problems – is strong. But if dirty
air was found to cause mental
illness, it would “open new
avenues to the prevention
and treatment of mental
conditions”, John Ioannidis at
Stanford University in California
wrote in a commentary in
PLoS Biology. ❚ Adam Vaughan
A MINI ice age that lasted for
125 years began in the middle of
the 6th century, helping to plunge
the world into an era of chaos. One
of the key events behind it was the
massive eruption of a volcano
somewhere in the southern
hemisphere. Now we may know
when and where it happened.
Huge eruptions fling so much
ash and debris into the atmosphere
that sunlight is partially blocked.
This can cool Earth and encourage
more ice to form at the poles, which
reflects more sunlight, further
cooling the planet. It has long been
thought that the eruptions of
volcanoes between AD 536 and
547 kick-started what is known
as the Late Antique Little Ice Age.
Robert Dull at California Lutheran
University and his colleagues have
now shown that the second of two
big eruptions during this time
appears to have occurred at the
Ilopango volcano in El Salvador.
The team found the remains of
three trees that “witnessed” this
event. Two of these were killed by
the volcanic activity.
Radiocarbon dating on multiple
tree rings inside the trunks revealed
their age – the trees died between
AD 503 and 545. Evidence from
ash deposits in nearby soil also
helped to confirm that a gigantic
eruption happened around this
time, most likely in late AD 539 or
540 (Quaternary Science Reviews,
An earlier big eruption is thought
to have occurred in AD 536, but
researchers haven’t yet managed to
identify which volcano was involved.
“I think the Late Antique Little Ice
Age was started by these eruptions
here and prolonged by others,” says
Michael Sigl at the University of
Bern in Switzerland. The final
proof that would tie Ilopango to
the AD 540 eruption would be to
find debris from it in Antarctic ice
cores from that time, he says. ❚
Our popular event is
coming to Boston …
November 23, 2019
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You’re in possession of one of the most complex and
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Discover why this is the most exciting time in the
history of brain science with six experts working at
the forefront of neuroscience, genetics and psychiatry.
Plus much more
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News In brief
How airborne microbes
conquered Mars-like desert
Atacama desert on grains of dust
carried by the wind, which may be
how they first colonised the desert.
The finding suggests that if there
are microbes on Mars, they could be
carried around the planet by global
dust storms, says Armando
Azua-Bustos at the Centre of
Astrobiology in Madrid, Spain.
The Atacama in South America
is one of Earth’s driest places, with
soils so parched they resemble
those of Mars. Some Atacama
microbes survive even in the driest
spots, but questions remain over
how they got there.
Azua-Bustos and his colleagues
suspected microorganisms arrived
on dust carried by afternoon winds
that blow in from the Pacific. To find
out, they set out Petri dishes filled
with nutrients in lines stretching
GENE editing can turn living cells
into minicomputers that can
record data and could track what
happens inside the body.
DNA computers have been
around since the 1990s, when
researchers created DNA able
to perform basic computer
functions. Instead of storing
information as 0s and 1s like
digital computers do, these
computers store information in
A, C, G and T, DNA’s molecular
code. One problem is that this
information doesn’t change
during a cell’s life, making DNA
computers very slow.
Now Fahim Farzadfard at
the Massachusetts Institute of
Technology and his colleagues
have created a technique that
uses DNA editing to speed up the
process. They call their system
DOMINO, for DNA-based Ordered
Memory and Iteration Network
16 | New Scientist | 31 August 2019
Operator. It is designed to
respond to various biological
cues, such as small molecules
or light, and builds on CRISPR
gene-editing techniques.
Current technologies used to
edit genes in cells or organisms
are limited. Their capacity to
store data stops after one or two
molecular events. In contrast,
DOMINO can be programmed to
edit DNA after complicated chains
of events, allowing it to encode
more information quickly.
One application for the
system could be to monitor
sugars, by programming it to
respond to lactose for example.
When a bacteria with the system
encounters lactose, DOMINO
would make changes to its DNA
(Molecular Cell, doi.org/c9n3).
The history of events are then
stamped onto the DNA in the form
of unique mutational signatures
that don’t fade over time even
after the cues, in this case lactose,
fade away, says Farzadfard. ❚
Ruby Prosser Scully
Space rock Ryugu
is a dustless oddity
THE MOST detailed pictures yet of
the asteroid Ryugu have revealed
something odd: a lack of dust.
After arriving in 2018, Japan’s
Hayabusa-2 spacecraft dropped
three landers and took a sample
from Ryugu’s surface. Now,
pictures from one of the landers
have revealed more details about
the composition of the asteroid.
Ralf Jaumann at the German
Aerospace Centre’s Institute of
Cells could become
computers in body
from the coast to the desert interior.
Any microbes flying in would land
in them. They found 28 species
growing in the dishes and extracted
DNA from several more that landed
but didn’t grow. The microbes came
from near the coast (Scientific
Reports, doi.org/c9pc).
Oceanobacillus oncorhynchi is
one of them. It lives in tidal pools.
Because the pools evaporate in the
heat of the day, it can survive being
dried out for hours – giving it a
chance of surviving the Atacama.
Azua-Bustos says such microbes
may have been the first to colonise
the desert. Mars is prone to dust
storms, so if there is any microbial
life there it could be dispersed on
dust grains. And if life can be moved
around Mars, contamination from
our probes could spread fast, he
says. ❚ Michael Marshall
Planetary Science in Berlin and
his colleagues have analysed the
images. They were surprised to
see the surface of Ryugu doesn’t
have a layer of dust (Science,
DOI: 10.1126/science.aaw8627).
This is strange because dust is
expected to accumulate through
collisions in space.
One explanation could be that
fine dust becomes charged due to
solar radiation and gets removed
by electrical forces, says Jaumann.
Another is that the release of
volatile gases from the surface
might have blown the dust away.
Or maybe, if Ryugu shakes as it
travels through space, the dust
could have gradually settled in the
interior of the asteroid, meaning
we can’t see it.
The pictures also revealed
details of rock texture on the
surface. The images show there
are two kinds of rock on Ryugu’s
outer layer, dark and rough or
bright and smooth, and they
both take up an equal share
of the surface. ❚ Abigail Beall
New Scientist Daily
Get the latest scientific discoveries in your inbox
Really brief
This material will
AGENTS might soon be able to
drop behind enemy lines and
leave no trace, thanks to a material
that can be made into gliders or
parachutes but that disintegrates
when exposed to heat or light.
The self-destructing polymer,
initially designed for use in
battlefield sensors, is the work of
Paul Kohl at the Georgia Institute
of Technology and his colleagues.
They began with polymers that
have a low ceiling temperature,
Honey can tell us all
about lead pollution
Bees pick up pollution as
they fly around and some
of it ends up in their honey,
although it is still safe to
eat. Kate Smith at the
University of British
Columbia in Canada found
that analysing honey is as
good a way to check lead
levels as using soil or air
samples. It could be used
to monitor remote areas.
the point at which the key bonds
in a material begin to break.
Lots of polymers slowly
decompose when they reach this
temperature because many
bonds have to be severed. But
Kohl designed his material so
that as soon as one bond breaks,
the whole thing unzips.
It is made from a chemical
called an aldehyde with various
additives that can either make the
material rigid for use in a glider or
sensor, or flexible to make a fabric.
Sunlight can trigger the
disintegration. Or, in true spy
style, a small light-emitting diode
App designed to spot
winter vomiting bug
Blood pressure
linked to brain size
People with high blood
pressure in their 40s seem
to have smaller brains at
age 70. The findings, from
a group of 500 people
aged between 69 and 71,
hints that looking after
your health may help
prevent some forms of
dementia (The Lancet
Neurology, doi.org/c9nm).
Time to get up and
move around a bit
Sitting for nine and a half
hours or more a day is
associated with a higher
risk of early death in middle
aged and older people,
according to a review of
data from over 36,000
individuals. The study
found that any level of
physical activity, regardless
of intensity, is linked to a
lower risk of premature
death (BMJ, doi.org/c9nw).
can be put in a device to trigger it
to self-destruct on demand.
When the substance falls apart,
all that is left is a residue and a
faint smell. Kohl and his team
have made a glider with a 2-metre
wingspan, and he says they can
make 5 kilograms of the polymer
at a time. The work was presented
at a meeting of the American
Chemical Society in California.
Marek Urban at Clemson
University in South Carolina
worries that the residue could be
toxic. Kohl says he has tested it
on plants, which survived. ❚
Chelsea Whyte
Two-child policy in China sees
millions more babies born
A CHINESE government policy
allowing all couples to have two
children led to an extra 5.4 million
births in its first 18 months.
China’s universal two-child policy,
announced in October 2015, was
designed to boost the country’s
stagnating population growth.
It targeted 90 million women of
reproductive age who already had
at least one child – 60 per cent of
these women were older than 35.
Susan Hellerstein at Harvard
University and her team looked at
data on 67.8 million births in most
of China from January 2014 to
December 2017. They measured
birth rates from July 2016 to
December 2017, covering the first
18 months after the policy began.
The team compared these with
baseline birth rates up to the end of
June 2016, nine months after the
October 2015 announcement.
In the 18-month period, there
were 5.4 million additional births
to women who already had one or
more children (BMJ, doi.org/c9n2).
Despite the national increase in
births, the total probably fell short
of the government’s annual target
of 20 million. China’s one-child
policy, introduced in 1979, was
scrapped amid concerns about an
ageing population and shrinking
workforce. ❚ Donna Lu
A SMARTPHONE app can detect
signs of norovirus, the most
common cause of gastroenteritis.
Jeong-Yeol Yoon and his team at
the University of Arizona used a
phone with an add-on microscope
and a light source to detect low
levels of norovirus in water.
Their technique can spot as little
as 10 attograms (10−18 grams) of
norovirus per millilitre, six orders
of magnitude better than other
portable detectors, says Yoon. That
is important, as even tiny amounts
of norovirus can trigger illness.
Also known as the winter
vomiting bug, norovirus is
notorious for causing vomiting
and diarrhoea in crowded
situations, such as on cruise ships.
At the heart of the team’s test
is a paper chip that contains tiny
beads of fluorescent polystyrene.
These beads contain antibodies
against norovirus. When virus is
present, it binds to clumps of
beads. Under the light, these
clumps fluoresce. Analysis via the
phone microscope reveals the
level of norovirus present.
The team is using it to test water
supplies. A diagnostic version for
checking stool samples is planned.
The research was presented at
an American Chemical Society
meeting in California. ❚ DL
31 August 2019 | New Scientist | 17
News Insight
Dawn of the pyrocene
20 | New Scientist | 31 August 2019
decades. This is probably because
of the way we are managing forests
to reduce the risk of fire.
Surprising as it may seem,
this year isn’t that special when
it comes to fire, either, globally
speaking. The European Union’s
Copernicus Atmosphere
Monitoring Service (CAMS) says
that some 3500 megatonnes
of carbon dioxide were emitted
from wildfires in the first half
of this year. At a global level, that
makes 2019 distinctly middling
compared with the past 16 years.
The fires in the north, however,
are exceptional. “This year has
been unprecedented for wildfires
in the Arctic,” says Carly Phillips at
the Union of Concerned
Scientists and Woods Hole
Research Centre in Massachusetts.
About 173 megatonnes of CO2
have been emitted from Arctic
fires so far this year, according
to CAMS, which is a record amount
(see chart, below). Russia has
been hit hardest, with more than
13 million hectares affected and
smoke hazes reported in cities.
So why the surge in Arctic fires?
The region is effectively stuffed
with fuel: huge swathes of forest
and peat. Most of this doesn’t
normally burn because it is cold
and wet. But this year, maximum
2019 data is
up to 18 August
The amount of carbon dioxide emitted by wildfires in the Arctic is a proxy for
how big the blazes are. The fires in 2019 are the largest for at least 16 years
Annual CO2 emissions
DEVASTATING wildfires across the
world have made front-page news
in recent times, from last year’s
deadly blazes in Greece to the
widespread property destruction
in Canada three years ago. One
place you might not expect to
be burning, however, is the Arctic.
Yet as New Scientist went to press,
millions of hectares of land in the
Arctic were ablaze.
Fire is a natural part of the
ecology of the vast boreal forests
that girdle Earth in northern
latitudes. But the amount of
vegetation that has been on fire
across Alaska, Canada and Russia
since June is highly unusual. Even
Greenland, four-fifths of which
is covered in ice, has seen fires.
The impacts on human health
and the environment are coming
into focus – and they are worrying.
Is there anything we can do?
This year has already seen
striking fires around the world,
including in places not usually
known for them, such as the UK
(see “Fires in February”, right). In
Indonesia, where fires are often
started to clear areas for oil-palm
plantations, the fire season may
prove to be as bad as that of 2015,
when blazes there created a plume
of smoke that extended halfway
around the planet. Brazil’s space
agency has reported more than
75,000 fires in the Amazon this
year, a record number. A surprising
number of crop fires have hit the
Netherlands, Germany and
Luxembourg, says Cathelijne
Stoof at Wageningen University
in the Netherlands.
You would be forgiven for
thinking that fires are on the rise
globally. In fact, the evidence
doesn’t bear that out. For example,
a 2017 study led by Niels Andela
at NASA used satellite images
to show that the amount of land
being burned worldwide has
actually decreased in recent
Wildfires raging in the normally wet Arctic could spur a powerful
feedback loop releasing yet more emissions, discovers Adam Vaughan
Siberia has been hit hard
by wildfires, as this
satellite image shows
temperature records have
tumbled, making it warm and dry
enough for blazes. “The north is a
big tinder box, but it’s been limited
from burning by the climate,” says
Merritt Turetsky at the University
of Guelph in Canada. “If you
remove those climatic constraints,
all those fuels are ready to go.”
Climate change could also be
contributing to the lightning
strikes that usually ignite the fires.
More lightning is linked to rising
surface temperatures. “Hot
weather is making the Arctic more
thunderstormy than normal,” says
Rod Taylor of the World Resources
Institute in Washington DC.
Most of the fires are in remote
regions, but that doesn’t mean
people are escaping the effects.
“What happens in the Arctic
doesn’t stay in the Arctic. Pollution
can carry thousands of miles
away,” says Elizabeth Hoy at NASA.
The agency has tracked smoke
from the fires in Siberia reaching
the US and Canada. That pollution
can combine with a city’s local
More Insight online
Sorting the week’s
supernovae from the
absolute zeros
Aerial Forest
Service battled
fires earlier this
away an insulating layer that helps
maintain permafrost – ground
that is normally frozen. This
makes it more likely that the
permafrost could thaw and
release even more CO2. Permafrost
thaws discharge not just CO2,
but also the more powerful
greenhouse gas methane.
The potential positive feedback
doesn’t end there. Researchers at
CAMS have already used satellites
to track soot from this year’s
northern Russia fires. Some landed
on ice in Greenland. That matters
because studies have shown that
soot can alter the reflectivity of ice,
making it absorb more of the sun’s
energy and heat up.
The remote nature and sheer
scale of the Arctic means there
isn’t a lot that firefighters can
do about these fires. Russia had
to send in the army, planes and
Fires in February
A WAVE of warm weather hit the
UK in February and three huge
fires broke out in different parts
of the country. In fact, the period
between June 2018 and June
2019 was a “really crazy year”
for wildfires, says Thomas
Smith at the London School of
Economics. The UK has had 95
large wildfires in 2019 already.
In the Arctic, it is often forests
that burn (see main story). In the
UK, peat and heathland blazes
are the main problem. “There is
potential once the fire is in the
peat of it being protracted. It’s a
more difficult fire to deal with,”
says Paul Hedley at the National
Fire Chiefs Council.
Since the 2018 moorland fires
near Manchester, the UK’s worst
in decades, the country’s fire and
rescue service has trained
35 staff nationally as wildfire
tactical advisers, to pool expertise
and aid coordination. Despite
this, wildfires are a growing
burden. “There is no way of
getting around it, it is a real
challenge for us,” says Hedley.
helicopters to tackle flames
in some areas. “Large-scale
intervention is very costly and
not very effective for large and
remote fires,” says Cristina Santín
at Swansea University, UK.
Russian authorities have tried
seeding clouds to induce rain.
The idea is that planes spray
chemicals such as silver iodide
in an effort to enhance the rate
of ice crystal formation in the
atmosphere, producing more
clouds, but there is no evidence
this is effective.
Today, firefighters’ priority is to
protect life and property. Turetsky
▲ Kakapo
The birds are back in
town. For the first time in
70 years, the number of
kakapos, New Zealand’s
giant parrots, has hit 200.
▲ Chunky chips
Ever wished microchips
were larger? Then
Cerebras Systems’s
(macro) chip could be for
you. It is as big as an iPad
and will be used for AI.
▼ Fogcam
Farewell to the world’s
oldest running webcam.
Fogcam had recorded
weather in San Francisco
since 1994, but will be
shut down because its
owners say there are no
good places to put it.
megatonnes of CO2 emitted from
fires in the Arctic so far in 2019
says that could in future be
extended to protecting rich stores
of carbon in the Arctic. “It might
be governments come together
to protect certain areas where we
understand where the old carbon
is,” she says. The other thing we
can do is to reduce CO2 emissions.
In the future, hotter, drier
conditions in the Arctic will set
the stage for more blazes. A recent
report on land use by the UN’s
climate science panel warned as
much. Stephen Pyne, who studies
the history of fire at Arizona State
University, says we are entering
the “age of the pyrocene”.
One crumb of comfort is that
the feedback loop can’t continue
forever. Once forest is burned, it
can’t keep burning. And smoke
from northern fires has a modest
cooling effect, reflecting some of
the sun’s energy. In the meantime,
however, the Arctic is still on fire. ❚
Read about geoengineering efforts
to refreeze the Arctic on page 38
▼ Cruelty
YouTube removed videos
of robots fighting each
other for defying animal
(not android) cruelty rules.
▼ Practice
A study found that good
violinists practise just as
much as even better ones,
suggesting the phrase
practice makes perfect is
far from perfect after all.
fumes to turn air quality from
average to poor, potentially
causing respiratory problems
for young, old and other
vulnerable people.
The health costs aren’t just
physical. Turetsky says that in
Yellowknife, the capital of the
Northwest Territories in Canada,
doctors have reported increasing
rates of hospital admissions for
post-traumatic stress disorder
during and following wildfires.
At a workshop she ran in the city,
many people reported what they
called eco anxiety. “A lot of these
people didn’t experience the fires
directly, but they know it’s going
to come back,” says Turetsky.
The effect on the climate could
be more serious still. The problem
isn’t simply that fires release a lot
of CO2. This will exacerbate global
warming, and Arctic wildfires have
released about the same amount
of CO2 this year as the Netherlands
does in a year.
“For me what is far more
insidious is the long-term
climate impact,” says Phillips.
Her worry is the prospect of a
harmful positive feedback loop.
Fires burn off vegetation, stripping
Your guide to a rapidly changing world
31 August 2019 | New Scientist | 21
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The columnist
James Wong delves
into claims that fruit
is bad for you p24
Using biomass
to make fuel is a
criminal waste p26
Three years’ worth of
shipping glints in the
English Channel p28
How the psychology
of happiness feeds a
vast industry p30
Culture columnist
Helen Marshall
on poking fun at
business culture p32
The right (not) to know
Genetic medicine challenges age-old notions of who should
share in a patient’s diagnosis, says Laura Spinney
NCE upon a time, a
doctor’s consulting
room was as safe as a
confessional. You could say what
you liked confident that, barring
very exceptional circumstances,
it would go no further. No more.
Two legal cases, one in Germany
and one still ongoing in the UK,
show how the limits of patient
confidentiality are being tested,
and how this challenges longestablished medical norms.
At issue is how to define a
patient in an era of genetic
testing. If a test shows that I carry
a disease-causing gene, that may
be relevant to other members of
my family. If I refuse to tell them,
should my doctor?
That is the nub of a trial coming
up at the High Court in London in
November, in which a woman is
suing the hospital that diagnosed
her father with Huntington’s
disease for not informing her.
Huntington’s is a fatal, incurable
neurodegenerative disorder
caused by a mutation in a single
gene. Every child of an affected
parent has a 50 per cent chance
of inheriting the mutation.
The woman argues that, had she
known her father’s diagnosis, she
wouldn’t have given birth to her
daughter, who is now herself at
risk of Huntington’s. Currently, in
the UK as in many other countries,
doctors are legally obliged to
respect the confidentiality of
patients unless they consent to
their information being shared.
Guidelines issued by
professional organisations such as
the Royal College of Physicians do
acknowledge that situations can
arise where a doctor has a duty of
disclosure to third parties even in
the absence of consent – notably
when not sharing information
could result in death or serious
harm. The High Court trial will test
whether that duty of disclosure
should also be recognised in law.
That could bring some much
needed clarity to the area, but also
create new problems. What if I test
positive for a disease-causing gene
variant and my family members,
who didn’t consent to be tested
themselves, don’t want to know
they are at risk?
This question was raised by a
German case in which a woman
sued a doctor for telling her that
her ex-husband had Huntington’s,
meaning that their two children
were at risk. The doctor acted
with the consent of his patient,
the ex-husband, but the
woman’s lawyers argued that
the information was useless to
her because the condition can’t
be cured and the children were
too young to be tested anyway.
Knowing her ex-husband’s
diagnosis without being able to
act on it, the woman claimed, had
sent her into a reactive depression
and left her unable to work.
The German case wound its way
through several courts before a
final decision was handed down,
in 2014, in favour of the doctor –
despite the fact that, unlike in the
UK, the right not to know is legally
protected in Germany, with
respect to genetic information.
Balancing these various rights
isn’t easy. Huntington’s is a clearcut case, medically: if you have
the mutation, you will develop the
disease, assuming you live long
enough. That is unusual. In most
cases, a gene test is likely to reveal
only an increased risk of disease.
The real problem is that the law is
black-and-white, while predictive
medicine is all about grey. ❚
Laura Spinney is a writer
and science journalist
based in Paris. Follow
her @lfspinney
31 August 2019 | New Scientist | 23
Views Columnist
Now that’s fruitloopery Ever heard the one about how
zoos stopping monkeys eating bananas tells us that fruit
isn’t good for us? Pull the other one, says James Wong
James Wong is a botanist and
science writer, with a particular
interest in food crops,
conservation and the
environment. Trained at the
Royal Botanic Gardens, Kew, he
shares his tiny London flat with
more than 500 houseplants.
You can follow him on Twitter
and Instagram @botanygeek
James’s week
What I’m reading
“Transforming the
Nutrition of Zoo Primates
(or How We Became
Known as Loris Man
and That Evil Banana
Woman)”. An excellent
chapter by Amy Plowman
and Francis Cabana from
the book Captive Care
and Management, Part II
What I’m watching
The TV adaptation of the
film What We Do in the
Shadows. I’m a total geek
even outside work.
This column appears
monthly. Up next week:
Chanda Prescod-Weinstein
24 | New Scientist | 31 August 2019
What I’m working on
Lots more writing and
radio projects, and I am
filming part of a new TV
F YOU have ever delved into
the world of online diet advice,
you might have heard the
claim that modern fruit is so
filled with sugar that it is unsafe
for zoo animals. It might have
come with links to media reports
with headlines like “Zoo bans
monkeys from eating bananas”.
The claim that fruit is no longer
a healthy part of the diet – for
humans as well as animals – has
gathered thousands of likes and
shares from low-carb devotees
around the world. But how good is
the evidence behind these claims?
As a botanist who knows rather
a lot about fruit, but very little
about monkeys, I decided to go
straight to the source, and talk to
the zoologist whose work first
spurred these stories.
Amy Plowman is director of
living collections at Paignton Zoo
in Devon, UK, and has done
pioneering research on the diets of
non-human primates in captivity.
She observed that the food given
to zoo monkeys was often a poor
reflection of what they ate in the
wild. In some zoos, it more closely
resembled the food preferences of
their human keepers.
“We have, whether consciously
or unconsciously, assumed
that human food is suitable for
non-human primates,” she says.
In some leading zoos, primate
species whose diet in the wild is
made up overwhelmingly of leaves
are routinely fed chicken, eggs,
cheese, yogurt, bread and noodles.
This understanding of primate
nutrition is, Plowman says,
“far removed from reality”.
To create a diet as similar to the
monkeys’ natural diet as possible,
she eliminated energy-dense
items such as meat, dairy and
grains, and reduced the amount
of fruit and some of the more
calorific vegetables. The monkeys’
new regime consisted essentially
of specialist primate feed pellets,
leafy veg and fresh tree leaves.
In a very short time, Plowman
and her team noticed dramatic
improvements in the animals’
health, with reduced obesity,
improved dental health and
even behavioural improvements.
The press enthusiastically
reported the story, focusing
almost exclusively on the angle of
zoo monkeys no longer being fed
bananas. When other institutions,
such as Melbourne Zoo, started to
follow suit, it triggered a further
flurry of headlines.
These news reports rarely
mentioned that many of the
“These conclusions
require us to ignore
one small detail:
humans aren’t
zoo monkeys”
animals involved in these new
feeding regimes, such as the red
pandas in Melbourne Zoo, are
essentially leaf eaters and don’t
actually eat much, if any, fruit in
their natural habitat anyway. But
then, pandas being fed bamboo
instead of fruit is less of a story.
Those who linked the switch to
the benefits of particular diets in
humans also failed to point out
that the new regime given to these
animals involved eliminating all
meat and dairy too, and swapping
to an essentially 100 per cent leaf
diet. Advocates of ultra-low carb
and meat-heavy “carnivore”
diets for humans were therefore
sharing research whose findings
were contrary to their claims.
What does Plowman think of
this interpretation of her findings
in zoo animals being used as
justification for excluding fruit
from human diets? “I wasn’t aware
of this and find it very surprising,”
she says. “Fruit and non-leafy
vegetables have a much lower
energy content than most of the
foods available to humans, so are
a very healthy option for us given
most of us consume too much.”
Stressing that her work on zoo
animals couldn’t be translated to
humans, she went on to say that
the dietary alterations she made
were to replace foods higher in
sugar and starch with indigestible
fibre, not replace it with fat and
protein. There is plenty of
evidence, she says, that a switch
from starch to fat and protein is
“definitely not” a good thing.
The evidence suggests
she is right. In several exhaustive
reviews of the best scientific
studies we have to date, higher
fruit consumption has been
consistently linked to a lower
incidence of obesity in humans,
as well as a reduced risk of
cardiovascular disease and
even certain types of cancer.
Perhaps more pertinently, if you
or I were put on a leaf-only diet we
would need to eat more than
300 cups of chopped, raw lettuce
a day. That wouldn’t be pretty. We
would struggle to get anywhere
near enough calories to meet our
daily needs, and would quickly
succumb to nutrient deficiencies.
It seems, much like zookeepers
of the past, our close-relatedness
to monkeys means many of us,
low carb activists included, can’t
help but project their needs onto
ourselves and vice versa. But to do
so requires us to ignore one small
detail, which even I as a botanist
can confirm: Humans aren’t zoo
monkeys. Shocking, I know. ❚
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Views Your letters
Editor’s pick
Using biomass to make
fuel is a criminal waste
27 July, p 23
From Fred White,
Nottingham, UK
Michael Le Page’s article barely
scratches the surface of the
problems with biofuel policy.
Solar energy conversion involving
wheat is around 0.06 per cent
efficient. That is 1/250th the
efficiency of the solar cells that we
now see covering agricultural land.
This idea takes no account of the
energy cost of planting, cultivation,
fertilisers, pest and disease control,
harvesting, processing and
distribution of biofuel. Cover roofs
in solar cells and leave the good
earth for food and nature reserves.
From Maarten van der Burgt,
Akersloot, the Netherlands
Having worked for many years in
the biomass field, I was delighted
to read Le Page’s article. Using
biomass to produce power or fuel,
when it has much more important
uses, should be a crime.
Politicians seem to believe that
because biomass is mostly green
it fits into a green future. Of course,
it is our only source of renewable
carbon. But the waste from sugar,
paper and wood processing is more
than sufficient to supply carbonbased feedstock for the chemical
and plastics industry as well as for
some very special fuels.
Are ‘septic foci’ returning
to haunt and hurt us?
10 August, p 42
From Hazel Russman,
London, UK
Debora MacKenzie reports work
suggesting that the gum disease
bacterium Porphyromonas
gingivalis is behind a range
of diseases.
When I was growing up in the
1950s, many believed that decayed
teeth served as “septic foci”,
spreading disease throughout
the body. I remember several
advertisements for toothpastes
26 | New Scientist | 31 August 2019
and mouthwashes that played on
this fear. Dentists usually removed
decaying teeth as a precautionary
measure instead of trying to
conserve them.
Then it was declared that bad
teeth were just bad teeth and
there was no such thing as a
septic focus. The idea dwindled
into pseudoscience. Is it back?
I was a climate change
denier but I got better
Letters, 13 July
From Bruce Denness,
Whitwell, Isle of Wight, UK
Lucia Singer refers to her teenage
concerns about global warming in
the 1980s and the existence even
then of deniers, who nowadays
attribute the undeniable warming
to natural fluctuations.
Sadly, I was at the time one of
those instinctive deniers. Being
professor of ocean engineering at
Newcastle University and a reader
of voluminous reports on deepsea drilling projects that referred
to past climate variability, instead
of just ignorantly sniping from the
bushes, I set about trying to prove
my point. This is how I failed.
Among those reports, one
interpreted global temperature
changes over the past 7 million
years from cores taken from the
Atlantic seabed. A diagram in it
seemed to show a sinusoidal
variation with a period of
4.8 million years, and variations
with successively smaller
amplitudes and periods of 2.4 and
1.2 million years. I was hooked.
I discovered hundreds of
references to proxy-temperature
variations, ranging from billions
of years down to the most recent
hundred or so years. All showed
the same summation of
sinusoidal curves with halving
period and reducing amplitude.
I built a simple model based on
those sinusoidal curves (see bit.ly/
Denness). Then I compared it with
the temperatures measured since
instruments were available.
This showed global temperature
consistently increasing above the
model’s forecast. I could explain
the difference only by adding
human-made heating – of about
3°C for every doubling of carbon
dioxide equivalent. I ate humble
pie in 1984 and have remained a
convert ever since.
In 2009, after several years of
global cooling, my model forecast
the precise scale of warming in
the middle of this decade – and
the pause in warming since.
It forecasts this to continue until
about 2030 with accelerating and
unstoppable temperature rise
after that. I would be delighted
to have my model proved wrong.
I don’t want to fry.
Looking on the bright side
of a large seaweed patch
13 July, p 17
From Paul Whiteley,
Bittaford, Devon, UK
You report the detection by
satellites of a giant seaweed patch
stretching from West Africa to
the Gulf of Mexico. This should
be seen as good news. It is taking
up nutrients and fertiliser run-off
from the land and turning them,
with minerals that are dissolved
in seawater, into the best compost
and soil conditioner I know of.
Farmers in Malta and elsewhere
have collected seaweed for
centuries in order to create new
soil and replenish the old. Farming
practices throughout the world
tend to result in increased erosion
and loss of soil quality. There
should be ships gathering up
this bounty to replace the tired,
mineral-deficient soils being
washed into the sea.
Not everyone depends
on thinking in language
Letters, 20 July
From Martin Greenwood,
Stirling, Western Australia
David Werdegar asserts we have
an “absolute dependency on the
signs and symbols of language”.
That is questionable: not
everybody thinks in the same way.
Composers clearly think in
musical terms that are sometimes
difficult if not impossible to
verbalise. Roger Penrose, in his
1989 book The Emperor’s New
Mind, uses his own experience,
and that of other distinguished
scientists, to argue that much
scientific and mathematical
thought is non-verbal.
More on mapping time
and language to space
Letters, 27 July
From Derek Bolton, Birchgrove,
New South Wales, Australia
Phil Ball suggests that Mandarin
speakers think of the future as
down because it matches their
direction of writing. Even if such
a correlation is found across all
writing systems, it could equally
be that the mapping of time to
space came first.
Spatial mappings can arise
where there is no writing. The
Yupno of Papua New Guinea
conceive the future as uphill, while
for the Aymara of the Andes it is
behind one, with the past in front,
perhaps on the basis that the past
is known, the future unknown
(2 June 2012, p 14).
The far right recycles
its ideas efficiently
17 August, p 24
From Anthony Wilkins,
Ripponden, West Yorkshire, UK
I enjoyed Graham Lawton’s
article on the exploitation of
environmental language by the far
right. I take exception, though, to
the idea that this has only recently
emerged. Far-right politicians
have often linked notions of
nationhood and the environment.
This was particularly evident
in the 1930s, when some Nazis in
Germany used the idea of a Volk
embedded within an environment
supposedly peculiar to a particular
race. So this is another example of
the ability of the far right to do its
own dispiriting sort of recycling.
I see downsides of drawing
water from the desert air
3 August, p 38
From Sam Edge,
Ringwood, Hampshire, UK
Attempts to draw water from the
air, and especially the use of metal
organic frameworks with their
non-intuitive properties, are
interesting. But what is going to
happen to flora, fauna and downwind weather patterns if large
amounts of moisture are pulled
from the atmosphere in already
arid environments?
Please get in touch if you
were on the Maths Bus
3 September 1994, p 6
From Lawrence Sithole,
Soweto, South Africa
Sue Armstrong reported nearly
a quarter of a century ago on
the Maths Bus that toured South
Africa. Some of your readers
were attracted to this educational
project and volunteered on and
supported the bus. I ask them to
get in touch through New Scientist.
Some obstacles to building
better hearing aids
Letters, 27 July
From John Woodgate,
Rayleigh, Essex, UK
Alan Gordon suggests hearing aids
should replicate the directionality
given by the shape of the ear. Most
manufacturers use test equipment
called a Head and Torso Simulator.
This can be fitted with external
ears to test the idea. It ought to
work. I haven’t yet tried it myself,
but I might be able to in the
near future.
My guess is that it doesn’t
work very well. If it does work, it
isn’t easy to see how to make its
appearance acceptable, especially
as hearing-aid manufacturers
try to convince people that the
aids should be as near to invisible
as possible. This is despite it
increasing costs and
compromising performance.
By the way, I’m nearly 82 and
am still able to work on things
to help people hear.
We are halfway to a carbon
sequestration solution
Letters, 3 August
From Barry Cash,
Bristol, UK
Butch Dalrymple Smith says
we should plant trees and make
things out of wood to sequester
carbon. We are already doing half
the job by farming trees to make
paper and chipboard. When we
have finished with them we
recycle or destroy them.
Why not preserve the paper
and chipboard as a way of storing
carbon? We would need to package
it to prevent decomposition. How
about baling the paper and then
coating it in plastic? We have lots
of waste plastic to recycle for that.
Slime, slime, glorious
healing slug slime
15 June, p 19
From Theo Rances,
London, UK
Leah Crane reports work on using
salamander mucus to help heal
wounds. This reminded me of the
time my father gashed himself
while working on a motorbike
engine. As someone whose
pharmacy training was
interrupted by a spell as ground
crew in the air force, he knew a
Want to get in touch?
Send letters to New Scientist, 25 Bedford Street, London
WC2E 9ES or letters@newscientist.com; see terms at
remedy used in the 1920s, and
dispatched me to find a large slug.
This he squeezed to make it exude
the slime that he found to be
healing for the wound.
I have never found the need to
repeat this treatment on myself.
I am surprised that Harvard
Medical School has discovered
the same phenomenon in
Chinese salamanders.
A surprising part of Gaia’s
self-correcting strategy
10 August, p 13
From John Entwisle,
Leatherhead, Surrey, UK
After reading your recent
article on the Gaia hypothesis,
I wondered whether anyone
had considered that the human
species may be a solution to one
of the biggest threats facing Gaia.
It seems that humans have just
the right amounts of aggression
and intelligence to create things
that could alter the trajectory of an
incoming asteroid that is capable
of causing a mass extinction.
The last one of these was quite
bad and the next could be worse. It
would be a risky strategy on Gaia’s
part, but if the species also enables
life to be established on a second
planet that would improve the
long-term odds of life’s survival.
Such a cool word
deserves to be used
13 July, p 15
From Rick McRae,
Canberra, Australia
Chelsea Whyte writes of moons
ejected from their orbits around
exoplanets, called “ploonets”.
She mentions the slow drift
in our moon’s orbit and the
possibility that this might be
its fate. Would this make it a
“protoploonet”? That is such
a cool word that it deserves
to be used.
For the record
❚ The common name of Protonibea
diacanthus is the blackspotted
croaker (1 October 2016, p 16).
31 August 2019 | New Scientist | 27
Views Aperture
28 | New Scientist | 31 August 2019
Channel vision
Photo European Space Agency
THIS is a picture of division,
but also connection. Hundreds
of radar images taken by the
European Space Agency’s twin
Copernicus Sentinel-1 satellites
from 2016 to 2018 have been
combined to give this view of
the English Channel.
Water deflects the radar pulses,
rendering the sea wine-dark.
Metallic objects, by contrast,
ping the pulses back strongly.
Most obviously, that reveals ships
as bright dots (though wind farms,
a recent addition to the seascape
off the UK, are evident, too).
Two lines of dots proceed
ant-like in their designated lanes.
The lower consists of ships bound
for ports such as Rotterdam in the
Netherlands, Antwerp in Belgium,
Hamburg in Germany and
Felixstowe in the UK; the upper
of ships travelling west to the
Atlantic. This was the first such
maritime “traffic separation
scheme”, introduced to reduce the
potential for accidents in 1967.
Bright dots of vessels queueing
to enter the ports of Southampton
in the UK and Le Havre in France
are also visible to the left of the
image, as is the pinch point of the
Dover Strait between Britain and
France, top right. Here the Channel
narrows to 33 kilometres, and the
container traffic conflicts with one
of the world’s busiest international
ferry routes: Dover to Calais.
The Channel has long been
the UK’s bulwark, reinforcing
a self-image of otherness,
independence and indomitability
most recently reflected in the
country’s 2016 vote to leave the
European Union. How leaving will
change the established patterns of
international trade visible in this
picture is anyone’s guess. But what
is clear is that in today’s world no
country is truly an island. ❚
Richard Webb
31 August 2019 | New Scientist | 29
Views Culture
The selling of happiness
Fuelled by government and corporate dollars, being happy has become near
mandatory. Douglas Heaven lifts the lid on an industry worth billions
Manufacturing Happy
Citizens: How the science
and industry of happiness
control our lives
THEY say money can’t buy
happiness. But that doesn’t stop
people from selling it. Day passes
to Goop’s wellness summit in
London in June cost £1000, with
weekend tickets (two nights in a
hotel, a VIP Sunday workout and
Goop-favourite meals) going for
an eye-watering £4500.
From mindfulness to detox
to the nine crystals you should
keep on your desk, actor Gwyneth
Paltrow’s multi-million dollar
business has it covered. There
are so many ways you can pay
to feel better about yourself.
I closed Goop’s website soon
after learning about shock-wave
therapy for my penis.
Happiness has become a
commodity that needs to be
topped up as often as possible.
What do we want? To be happy.
When do we want it? Now.
At some point, our happiness
became other people’s business.
“Most of what we do on behalf
of our happiness… is first and
foremost favourable and
beneficial to those who claim
to hold its truths,” write Edgar
Cabanas and Eva Illouz in the
excellent Manufacturing
Happy Citizens.
Educational psychologist
Cabanas and sociologist Illouz
explain how happiness became
not only a commodity, but also
one that society has decided it is
our civic duty to pursue. Happy
people are better citizens. The
book is a clear-sighted critique
of capitalism’s current obsession
30 | New Scientist | 31 August 2019
Edgar Cabanas and Eva Illouz
with happiness and of the shaky
science allowing a well-meaning
ideal to be so easily subverted by
governments and companies.
It is surprising that happiness
(at least, as we know it today) has
an origin story. In this tale, the
prime mover is Martin Seligman,
a behaviourist and cognitive
“In his paper, Seligman
wrote that positive
psychology called to
him just as the burning
bush called Moses”
scientist. In 1998, he was elected
president of the American
Psychological Association, the
largest professional body for
psychologists in the US. He had
come to believe that psychology
was too negative, focusing on
pathologies, not betterment.
Seligman wanted to make
happiness the focus: what was
it and how could we achieve it?
It was a real calling. In his joint
2000 paper “Positive Psychology:
An introduction”, published in
American Psychologist, Seligman
wrote that “Positive psychology
called to me just as the burning
bush called Moses.” But according
to Cabanas and Illouz, “as is often
the case with revelations, the
picture of positive psychology
presented in the inaugural
manifesto was vague”. They say
that Seligman cherry-picked ideas
from a grab bag of disciplines
he felt said something about
the human condition, including
evolutionary biology, psychology,
neuroscience and philosophy.
Seligman was clear about one
thing, however: happiness studies
shouldn’t be part of psychology
but a new field.
The authors argue that it wasn’t
entirely new: positive psychology
sounded a lot like the self-esteem
movements of the 1980s and 90s,
the humanist psychology of the
1950s and 60s, and the thinkyourself-well and mind cures
promoted by the likes of Christian
The impact of happiness
research has been huge –
just not on science
Science at least 150 years earlier.
The enterprise might have
fallen flat if the money hadn’t
poured in. Cabanas and Illouz
quote Seligman saying that
“grey-hair, grey-suited lawyers”
from “anonymous foundations”
that only picked “winners”
would call him for meetings
in fancy buildings in New
York to ask what positive
psychology was and request
“ten-minute explanations”
and “three-pager” proposals.
Within two years of his paper,
the field had attracted some
$37 million. The John Templeton
Foundation gave Seligman
$2.2 million to set up the
Positive Psychology Center at
the University of Pennsylvania.
The 2002 preface to the Handbook
of Positive Psychology, which
declared the field’s independence,
was written by Templeton himself,
Don’t miss
Driving forces
Nothing can be taken for granted in an
autonomous future, finds Simon Ings
Who is in control?
Science Museum, London
Until October 2020
DURHAM Cathedral’s stained
glass windows inspired artist
Dominic Wilcox’s contribution
to Driverless, a tiny but
thought-provoking exhibition
at London’s Science Museum.
It occurred to Wilcox that
artificial intelligence could make
traffic collisions a thing of the
past, which means “we don’t
need the protection systems
that are built into contemporary
cars”, he told design magazine
Dezeen. “We can just have a
shell of any design.”
His Stained Glass Driverless
Sleeper Car of the Future
(pictured below) is the sort of
vehicle we may be driving when
road safety has improved to
the point where we can build
cars out of whatever we want.
It suggests a future in which
safety is no longer a set of
barriers, cages, buffers and
lights, and is instead a dance
of algorithms. Rather than
measuring out a bike lane, say,
we will have an algorithm that
decides whether to leave a
smaller distance to the bicycle
on its left to reduce the chance
of hitting a truck on its right.
What if that causes more
cyclists, but fewer passengers,
to die every year? Such
questions aren’t new. But
they are having to be asked
again and in a different and
disconcerting form as we move
more safety systems off the
roads and into vehicles.
On show is the Massachusetts
Institute of Technology’s “Moral
Machine”, a website using more
than 40 million participants’
decisions on what to do in
certain situations to inform our
autonomous machinery design.
The findings can be unsettling:
would-be designers are more
likely to sacrifice your safety if
you are fat, a criminal or a dog.
This is a show as much about
possible futures as it is about the
present. Interviews, archival
footage, models and some
interactive displays create a
series of provocations, more
than a fully fledged exhibition.
I especially liked the look
of the MIT Senseable City Lab
and the AMS Institute’s
“Roboats”, currently on trial on
Amsterdam’s canals. These
autonomous floating platforms
form spontaneous bridges and
event platforms and can
transport goods and people.
The exhibition spends
much of its time off-road,
investigating drone swarms and
privacy, flocking behaviour and
mine clearance, ocean mapping
and planetary surveillance.
Don’t let its size put you
off: this little show is full of
big surprises. ❚
An autonomous racing drone
and a car made of glass: which
future would you pick?
Open City
Documentary Festival,
in London from 4 to
10 September, presents
Expanded Realities,
an exhibition and
symposium about how
digital technology is
changing and enriching
non-fiction film.
Ars Electronica, since
1979 the big beast of
the European science-art
scene, is contemplating
the digital revolution
in middle age. Artists,
scientists and tech
pioneers of the past four
decades will be gathered
in Linz, Austria, from
5 to 9 September.
The Nature of Life and
Death (Putnam) by
forensic ecologist Patricia
Wiltshire blends science
and true-crime reporting.
It reveals the microscopic
traces we leave behind
us, and how these are
used to reconstruct our
most desperate acts.
31 August 2019 | New Scientist | 31
Douglas Heaven is a consultant for
New Scientist
apparently “thrilled by the
project, given his interest in
how individuals can control
their minds to master their
circumstances and shape the
world”, write Cabanas and Illouz.
The message spread via
meetings, symposiums, textbooks
and journals, aided by a receptive
press. In its grand promises, there
was something for everyone. Still
more bodies paid for scholarships
and prizes. The US National
Institute on Aging and what is
now called the National Center
for Complementary and
Integrative Health both funded
research. Companies such as
Coca-Cola invested, hoping to
find ways to reduce employee
stress and promote productivity.
One of the largest grants now
comes from the US Army through
its $145 million Comprehensive
Soldier Fitness project, run closely
with Seligman and his centre.
Is there anything in all this?
Here, Cabanas and Illouz are
careful. It is hard to take down
a hugely successful area that has
globally reinvigorated psychology
departments. Still, there are many
critics who attack everything from
its theoretical simplifications to
its methodological shortcomings.
The authors write: “The field is
characterized by its popularity
as much as its intellectual deficits
and scientific underachievement.”
Though its scientific impact
is questionable, elsewhere the
impact of positive psychology
has been huge. It has reshaped
attitudes towards happiness,
changing how firms think about
staff, governments view citizens
and how we think about ourselves.
It feeds a billion-dollar wellness
industry. At least some people
have something to smile about. ❚
Views Culture
The science fiction column
A surfeit of snake oil Ordinary lives hang in the balance when self-appointed
industry disrupters roll into town. Let’s hear it for novelists who puncture and poke
fun at a business culture disconnected from its people, says Helen Marshall
Helen Marshall is an editor,
award-winning writer
and senior lecturer at the
University of Queensland,
Australia. Follow her on
Twitter @manuscriptgal
The Return of
the Incredible
Exploding Man
Dave Hutchinson
The Warehouse
Rob Hart
Bantam Press
Helen also
The Silver Wind
Nina Allan
Titan Books
A haunting collection of
uncanny time-travel stories.
World Engines:
Stephen Baxter
Follow a strange object on
its 500-year orbit of Earth.
32 | New Scientist | 31 August 2019
Life in a one-horse town
teaches you there is no
such thing as a free lunch
THE pulp novels of the 1950s are
best remembered for their sense
of wonder. This is exactly the
feeling that billionaire tech funder
Stanislaw Clayton tries to create
in The Return of the Incredible
Exploding Man, the latest novel
by Dave Hutchinson, author
of the deservedly praised
Fractured Europe series.
The 1950s were also a golden
age for social satire: for Pohl and
Kornbluth’s The Space Merchants,
and Vonnegut’s Player Piano.
Hutchinson’s new book is, in
truth, more this sort of science
fiction. It bites.
The novel follows down-andout journalist Alex Dolan as
he agrees to write a book
documenting the history of
Clayton’s latest project: the Sioux
Crossing Supercollider. What
Clayton has in mind is a PR
exercise designed to build support
for his struggling project. He gets
a lot more than he bargained for.
The bulk of the novel is a
slow-burn account of Dolan’s
investigation into the mysteries
surrounding the project, part le
Carré spycraft, part Crichtonesque
scientific thriller. There is
something of Stephen King, too,
in the book’s close focus on the
inhabitants of Sioux Crossing,
ordinary folk transformed by
Clayton’s regeneration of their
town. For better or worse, they
need him to succeed. If the project
fails, it will take the town with it.
In the finale, we might expect
this book to live up to its pulpy
“The Cloud has become
the only game in
town: a vast system of
warehouses sustaining
a mini-ecosystem”
title, but by now Hutchinson has
become more interested in the
politics than in the science. Some
readers might feel deflated, but
Hutchinson’s point is well made:
that we ought to be suspicious
of technocrats bearing gifts.
The Warehouse by Rob Hart is
similarly interested in the effects
of a billionaire’s ambitions on
everyday people. In it, Gibson
Wells, an American entrepreneur
peddling a dangerous brand of
ultracapitalism with folksy charm,
creates The Cloud. In the wake of
climate change and a ravaged
economy, The Cloud has become
the only game in town: a vast
system of warehouses supporting
a mini-ecosystem with its own
living spaces, restaurants, social
ratings and credit system. Think
Amazon, but on steroids.
Paxton, a former entrepreneur
whose company failed after The
Cloud undercut his business, has
found work as a security officer,
charged with stopping the flow
of illegal drugs into The Cloud’s
compound. Zinnia is ostensibly
a picker, one of the redshirts
running a daily marathon to locate
cheap goods for drone delivery to
the outside world. But she isn’t all
she seems. A competing company
has offered her a life-changing
sum of money if she can ferret
out The Cloud’s secrets.
The Warehouse depicts a
world of systemic abuse, petty
corruption and a callous disregard
for the things we need to be
properly human. But while Hart
spends a decent amount of time
exploring Wells’s justification for
The Cloud, Paxton’s complicity is
the main point: will he buy into a
system he knows is fundamentally
broken or will he risk his relative
comfort to tear it down?
Ultimately, is The Warehouse
a novel that puts the capstone
on post-industrial capitalism?
Not really. Rather than trusting
his own story, Hart relies on
references to Orwell, Atwood,
Bradbury and Le Guin to
explain his ethical stance. The
result is an entertaining, almost
cinematic read, but one that is
content to let others do the
intellectual heavy lifting. ❚
Features Cover story
Back stor
Chronic back pain is on the rise,
and the most common treatments
may be making matters worse,
finds Helen Thomson
34 | New Scientist | 31 August 2019
RGHH.” The first time it happens
it takes you by surprise. Was that me?
Then it happens again, and again.
You give a tiny groan every time you get off the
sofa. You hold the bottom of your spine and
stretch, wondering if you should see a doctor.
Surely you are too young to have a bad back?
That tends to be the start for a lot of us.
Backache is an extraordinarily common
burden, with one in four adults experiencing
it right now, and 90 per cent of people having
back pain at least once in their life. Last year,
a series of papers in The Lancet revealed the
extent of the problem: back pain is a leading
cause of disability around the world. In the US
alone it costs an eye-watering $635 billion a
year in medical bills and loss of productivity.
Much of the blame has fallen on our
increasingly desk-bound lifestyles and
growing lifespans, which mean more years
of wear and tear on our spines. But these
factors only partly explain how we got here
and what makes some people more vulnerable
or resilient. The World Health Organization
expects back pain problems to steadily rise
in the years ahead and to affect more people
around the globe. That makes it especially
worrying that the people who are trying to
help are making the problem worse.
The good news is we already have the
knowledge to improve things – if we finally
apply it. At the same time, new understanding
of how and why our brains create the
experience of pain is changing the way
we think about those crippling aches and
pointing to some surprising solutions.
To understand the solutions, we must
first travel back 7 million years, to when our
ancestors caused the problem. In exchange
for walking upright, we got back pain. At least,
that is the hypothesis posited by Kimberly
Plomp at the University of Liverpool, UK,
and her colleagues.
To find out why humans experience more
spinal disease than non-human primates,
Plomp’s team studied the shape of human,
chimpanzee and orangutan vertebrae, the
bones that make up your spine. They were
looking for small bulges called Schmorl’s
nodes that can occur in the soft tissues
between vertebrae and are linked to back
pain. People who had these nodes had
vertebrae that were more similar in shape
to those of chimpanzees. “We started to walk
on two feet relatively quickly in evolutionary
terms,” says Plomp. “Perhaps some individuals
with vertebrae that are more on the ancestral
end of normal human variation are less well
adapted to withstanding the pressures placed
on the bipedal spine.” This ancestral vertebral
shape then plagued us throughout our history
because it didn’t affect our ability to reproduce,
so evolution didn’t select against it.
“People say they
can tell you
what is wrong
from a scan.
They can’t. It’s
not possible”
Yet despite its long evolutionary history,
it is only in the past few decades that we have
started to see an epidemic of chronic back
pain (see graph, page 36). What changed?
There is evidence that the rise of office
culture plays a part. Several studies have found
a link between spending more time sitting on
the job and increased reports of lower back
pain. Slumping in front of computer screens
puts pressure on the muscles, ligaments and
discs that support the spine and can deactivate
muscles that promote good posture.
Of course, backache can also be caused
by accidents, sports injuries or a congenital
disorder, but it is lifestyle factors such as
obesity and smoking that are the real problem,
says Rachelle Buchbinder at Monash
University in Victoria, Australia, one author
of The Lancet series.
Smoking probably puts people at higher risk
of lower back pain because it is associated with
a clogging of the arteries, which can damage
the blood vessels that supply the spine, leading
to muscle and bone degeneration. Being
overweight amplifies the mechanical strain on
the back and decreases mobility, predisposing
people to deterioration of discs in the spine.
Obesity can also increase the production of
inflammatory chemicals associated with pain.
Unfortunately, identifying which of these
problems has led to your own back pain is
incredibly difficult. According to one study
in the US, nearly a quarter of all primary care
appointments for adults are for back pain.
Less than 1 per cent of people who seek help
will have something seriously wrong, such as
an infection, inflammatory arthritis, cancer
or a fracture, says Buchbinder. These people
will usually have other red flags, such as fever,
rapid weight loss or problems going to the
toilet. Everyone else falls under the category
of “non-specific back pain”, which usually
improves in a matter of days or weeks.
Yet many people and their doctors pursue
MRI scans in the belief that they will provide
an accurate diagnosis, and therefore quicker
recovery. The trouble is, “by the time we’re
50, many of us will have abnormalities in our
spine: degeneration of the discs, bulging, a
little arthritis in the joints”, says Buchbinder.
“Some of these may cause pain in some people
but not others. There are lots of people that
say that they can tell you what is wrong from
a scan, but they can’t. It’s just not possible.”
Getting a scan may not only be a waste of
time and money, says Buchbinder, but it can
actually worsen your back pain. Once you start
to look for abnormalities, you will find them.
Once that happens, doctors are more likely
to prescribe painkillers, steroid injections or
surgery, which may be unnecessary, ineffective
and sometimes harmful.
In 2003, Jeffrey Jarvik at the University
of Washington in Seattle and his colleagues
randomly assigned 380 people with lower
31 August 2019 | New Scientist | 35
back pain to have an X-ray, which can identify
things like fractures, or an MRI scan, which is
used to look at soft tissues. A year later, there
was no difference in their health outcomes,
but those who had an MRI were more likely to
have had surgery, exposing them to the risk
of infection and other complications. “The
potential for harm has been shown in many
studies,” says Buchbinder.
In countries like the UK, where doctors are
advised against offering surgery for back pain,
people are often offered anti-inflammatory
steroid injections, but these have been shown
to be no more effective than placebo. They can
also cause increased appetite, mood changes
and difficulty sleeping.
Moreover, many doctors, particularly in
the US, prescribe stronger painkillers than
are necessary, says Buchbinder, fuelling
the opioid crisis that has decreased life
expectancy in the US. Backache is the number
one reason for prescribing opioids, says
Tamar Pincus, a health psychologist at Royal
Holloway, University of London, despite
several studies showing that safer treatments,
such as non-steroidal anti-inflammatories,
may offer similar relief.
Not all back pain is bad. The initial pain we
get from an injury alerts us to a problem and
protects us from further damage. This
mechanism can be critical to our survival. But
chronic pain that lasts weeks, months or years
after an injury has healed serves no useful
purpose and can seriously harm our health.
Most people assume that pain must always
have a physical cause – an injured muscle or
“Low mood and
guilt increase
the risk of pain
squashed disc, perhaps. Yet often there is no
identifiable mechanical explanation. That is
why many specialists instead focus on how and
why we perceive pain. Fundamental to this idea
is our understanding that pain is generated by
the brain. Although we have cells in our body
that send messages to the brain to alert us to
potentially damaging stimuli, like heat, or a
sharp object pressing against the skin, it isn’t
necessary to stimulate these cells to feel pain,
nor is their activity always directly related to
our experience of discomfort.
Irene Tracey, a clinical neuroscientist at the
University of Oxford, was fundamental in
uncovering these nuances. In the 1990s, her
Growing pains
Disability-adjusted life years (millions)*
Disability related to lower back pain has increased dramatically around the world in the past few decades
Age group
*A disability-adjusted life year is the equivalent of one lost year of “healthy life”, according to the WHO
36 | New Scientist | 31 August 2019
team showed that anticipation of pain made
networks in the brain light up with activity, and
that different aspects of our experience – the
intensity of pain or anxiety caused by it – are
controlled by separate brain circuits.
All of these circuits can be triggered or
suppressed. For instance, people who are
depressed show greater activity in pain areas,
but this can be subdued by listening to music
or watching a gripping film. One experiment
even showed that religious faith could have
analgesic properties in the brain. When devout
Catholics were shown pictures of the Virgin
Mary while given a sharp pain, they rated their
pain lower than atheists shown the same
image. When both groups were shown a nonreligious painting, their pain rating didn’t
differ. Scans showed that the religious
iconography triggered a brain area in the
Catholic group called the right ventrolateral
prefrontal cortex, which inhibits pain circuits.
With chronic back pain, understanding how
the experience of pain can be manipulated by
the mind is important to figuring out why it
sticks around after an injury has healed – and
what we can do to prevent this. Pincus points
out, for instance, that low mood and painrelated guilt increase the risk of pain becoming
chronic. “People start to feel guilty for
dropping out of activities,” she says. “They
then worry that people are going to judge them
for that, so they don’t accept the activities in
the first place.”
After several bouts of back pain, people
also start to process the world differently, says
Pincus. Their pain becomes embedded within
their “self-schema”: the things they associate
with themselves. If they are shown an image
of a staircase, for instance, their first thought
is, “I can’t climb it”.
“After a while, you see and feel things
coated with pain,” says Pincus. “You no longer
need the injury to feel pain. And you might
experience more intense pain, purely because
you’re expecting it.”
So between our brain and the rest of our
body, what can we do to avoid or diminish
chronic back pain? First, you may want to
rethink your back belt, shoe insoles and any
other ergonomic products, since there is
almost no evidence that they are effective.
Once they are out of the way, it is time to
get up and go. Despite doctors all over the
world still prescribing bed rest, it is one of
the worst things you can do. When young
healthy male volunteers spent eight weeks
in bed, their lumbar multifidus muscles,
which keep our lower vertebrae in place,
had wasted and become inactive. Some of
People who
switch to
standing desks
say they feel
less back pain
the volunteers’ muscles had still not recovered
six months later.
“Many low-back-pain patients have a strong
fear of moving,” says Luana Colloca, a pain
specialist at the University of Maryland School
of Nursing. Yet exercise can make all the
difference. A study published in June found
that exercises designed to strengthen the lower
back help ease pain, and just walking regularly
helps too. “We need to remove this fear and
persuade ourselves to exercise,” says Colloca.
Small changes in how we work can also help.
People with chronic back pain who used a
standing work station for three months saw a
significant decrease in the worst pain they felt,
and their general pain at the end of the study.
If chronic back pain is already plaguing you,
give some thought to your mind. “It’s no good
asking someone to stop thinking about their
pain,” says Pincus. “It’s like telling someone not
to think of a white elephant.” Instead we should
concentrate on reframing the world so that the
things you like doing don’t lead your thoughts
back to pain. For instance, Pincus herself
experiences chronic pain after a knee injury,
but says that when it hurts when she is out
with her children, she feels happy, rather than
sad. “I feel fantastic. I think: ‘You’re an amazing
mum because you’re out walking with your
kids.’ How we think about our pain may not
affect the pain intensity, but it does affect the
ability of that pain to infiltrate our daily lives,
which creates that negative cycle that can
destroy our lives.”
Back me up
Clinicians also need to do their bit, says Pincus.
When we are injured, our friends say: “Ooh,
that must hurt.” They acknowledge our pain.
Doctors often forget to do so, and that matters.
In one study, 50 people were asked to hold a
bucket of sand with a straight arm for as long
as they could, while listening to a distressing
sound. It is a surprisingly painful task.
Immediately after, they were asked to perform
tests in which they had to recall lists of words.
They then chatted to an examiner who either
validated or invalidated their pain, before
recalling as many words from the original
tests as possible.
Most participants told the examiner that
they found the task difficult, that it hurt their
arm and that they were disappointed that they
couldn’t hold the bucket for longer. In the
validation group, the experimenter replied:
“That’s a really common response, many
people feel surprised over the level of pain that
the task brings about. When something looks
easier than it is, it’s often hard to live up to
one’s own expectation.” In the other group,
the experimenter would say: “That’s strange.
Nobody else described their experience this
way. No wonder you’re disappointed.”
People whose painful experience was
dismissed remembered fewer words on
average and three times as many words that
weren’t there, compared with the group whose
pain had been acknowledged. “Until you get
validation of your pain, your brain’s resources
are completely swept up with how to
communicate your suffering,” says Pincus.
“Doctors need to acknowledge this. If patients
are able to be heard, they can understand.”
The best way to prevent long-term disability
from back pain is to ditch the drugs and
promote wider international adoption of a
mix of increasing physical activity plus mental
retraining, suggest Buchbinder and her
colleagues. There is reason to hope that plan
will work. In the Australian state of Victoria,
workers’ compensation claims for back pain
tripled in the early 1990s. Then in 1997, a statewide public health campaign encouraged
people to avoid bed rest and unnecessary
scans. It also gave them tips on how to think
about pain and its impact on their life. By the
time the campaign was over, there was a
significant drop in the number of claims for
compensation for back pain, compared with
a nearby state, which saw no change.
When you are in pain, the last thing you
expect to be told is that you should stay away
from the doctor and get back to work. For
backache, that may truly be the best advice,
says Buchbinder. Perhaps we need to start
thinking about bouts of back pain the way
we think about other common ailments, says
Pincus. “Nobody expects to get through life
without a cold,” she says, “and they don’t visit
the doctor when they do.” ❚
Helen Thomson is the author of
Unthinkable: An extraordinary
journey through the world’s
strangest brains
31 August 2019 | New Scientist | 37
If we want to save the
Arctic, we might have to
intervene directly. Rowan
Hooper investigates three
ambitious projects to
bring back the ice
38 | New Scientist | 31 August 2019
HE Arctic is in a death spiral. The top
of our world is heating up faster than
anywhere else on the planet, setting
new records for the speed and area of ice melt.
We are on track this year to have one of the
lowest summer sea ice coverages so far. It is a
huge problem, because what happens in the
Arctic doesn’t stay in the Arctic.
What’s more, the Greenland ice sheet, which
alone contains enough water to raise global sea
levels by 6 metres, is disappearing. The frozen
Arctic soil and sediment, or permafrost, is
melting, releasing more and more carbon
dioxide and methane into the atmosphere.
This year, vast wildfires in the peatlands of
Siberia have blazed for more than a month,
and the Arctic warming is playing havoc with
weather systems in the northern hemisphere
too. But if you prefer to think simply in terms
of money, the economic impact of unmitigated
Arctic warming by the end of this century was
recently estimated to be $67 trillion. As US
congressman Jerry McNerney says: “When it
comes to the Arctic, we’re in deep shit.”
You’ve heard the slogans: we are living in a
time of climate emergency. But it is no good
declaring an emergency without summoning
help. So here it is: let’s refreeze the Arctic. There
are several imaginative ideas to manipulate its
climate system to get the ice back. They won’t
be cheap or easy, but some researchers argue
that the crisis in the north is too serious not to
at least investigate ways to engineer the return
of the ice.
Climate intervention in the Arctic might be
more necessary than it first appears because
the region’s death spiral is a feedback loop.
As the shiny ice melts, models and satellite
images suggest we could get a sea ice-free
summer any year now. When the ocean is
exposed, instead of reflecting sunlight, the
dark water absorbs more of the sun’s heat. Over
the past 30 years, this change corresponds to a
warming equivalent to a quarter of all the
carbon dioxide released by human activity
during that time. The warming is weakening
the polar jet stream – the fast-flowing, highaltitude air current – in the northern
In 40 years, about 2.4 million
square kilometres of Arctic
sea ice has disappeared
hemisphere, resulting in more“blocked”
weather patterns, and corresponding
droughts, floods and heatwaves.
The global risks are huge. “Allowing the
Arctic to change in unrecoverable ways poses
an enormous safety risk to communities
around the world and could move the climate
system beyond our ability to recover,” says
Kelly Wanser, director of SilverLining, a
geoengineering NGO based in Washington DC.
Of course, we could have prevented the
Arctic from warming as much as it has if we
had cut global greenhouse gas emissions
when scientists first started advising us to
do so, decades ago. But we didn’t, and nor
are we now. “It’s a pious hope and anyway it
would take a while,” says Peter Wadhams,
head of the Polar Ocean Physics Group at
the University of Cambridge.
This is why a growing number of scientists
argue that, if we want to save the Arctic, we
need to intervene directly by manipulating its
climate system. There are three main proposals
for doing this: increasing the extent of sea ice;
“It is no good
declaring a
help. So here it
is: let’s refreeze
the Arctic”
artificially brightening the surface of the ice to
reflect more sunlight; and cooling the Arctic air
by brightening the clouds to deflect sunlight.
All three ideas are forms of geoengineering:
intervention in the environment on a scale big
enough to counteract climate change. The
concept bothers many scientists because they
fear that the idea of a technological fix will
undermine efforts to cut carbon dioxide
emissions. “Well, we’re not making them
anyway,” says Cecilia Bitz, a sea ice physicist
at the University of Washington in Seattle.
“Maybe intervention would be positive,
showing that we have the capacity to improve
the environment.”
For those advocating such action, a big
concern is the methane already streaming out
of the seabed as microbes break down thawed
organic matter. “The fear is that this will grow
from being a set of methane plumes to an
outbreak,” says Wadhams. “So we need to bring
back the ice around the coastal seas, and that
might save us from a catastrophic methane
burst.” As well as this methane trapped under
the sea, an estimated 1 trillion tonnes of carbon
are in the top 3 metres of Arctic soils. If only a
small fraction of this reaches the atmosphere,
it will overwhelm any cuts in emissions we
have made. “It seems that nature offers us a
choice: instant methane from the seabed
giving us a huge immediate burst of warming,
or longer, slower warming from complex
chemical processes as terrestrial permafrost
thaws. Except that it’s not an ‘or’, it’s an ‘and’.”
The first potential solution comes from
Steve Desch, an astrophysicist at Arizona State
University. His plan is to build windmills that
pump seawater onto surface ice during the
winter, where it will freeze, thickening the sea
ice and extending its coverage. This method
was recently proposed to prevent the collapse
of the Antarctic ice sheet too.
Sea ice moves around, so Desch’s idea is to
locate the windmill-pumps on sea ice in the
north of the Arctic. This would help thicken
chunks of ice that are then protected from
melting when they move south. “While that
may seem like an impossible task, since the
Arctic is a very large place, we outlined a
mechanism, using simple, brute-force,
steampunk technology that is not impossible,
but enormous in scope,” he says. “It’s not like a
space mirror larger than the Earth or
something. It’s pretty simple, but just a big job.”
Desch has calculated that we would need >
31 August 2019 | New Scientist | 39
How to be Superhuman
Rowan Hooper is speaking at New Scientist Live
about people at the peaks of human potential
Last ice?
About one-third of the Arctic’s summer
sea ice has disappeared over the past
40 years. This is an area of approximately
2.4 million square kilometres – roughly
the size of Algeria
Sept 1979
7.1 million km2
Sept 2018
4.7 million km2
2,382,000 km2
“Arctic sea ice may be restored
by brightening ocean
stratocumulus clouds”
Reflective microspheres
(below left) are being used to
preserve winter ice in North
American lakes (right)
40 | New Scientist | 31 August 2019
10 million windmills across the entire Arctic to
refreeze it, at a cost of $500 billion. That is a
huge sum, but just a fraction of the estimated
$67 trillion economic impact of Arctic warming
if we don’t act. Bitz has evaluated Desch’s idea
in a paper currently submitted for publication.
“The physics can work,” she says. “The basic
principles make sense. To me that’s
promising.” But so far, Desch only has a
prototype windmill that works in the lab.
For a true test, field trials are essential.
The second proposal for geoengineering
the Arctic has had some success outside the
lab. It involves covering the ice with shiny,
white beads. The idea is that these microbeads
increase the reflectiveness, or albedo, of thin,
young ice, so protecting it from the sun. The
leading advocate is Leslie Field, an engineer at
Stanford University in California, who also
runs Ice911 Research, a non-profit organisation
exploring methods of restoring Arctic ice,
mainly using hollow silica microspheres.
These bright, non-toxic beads are chemically
and physically similar to sand but smaller,
more like powder, with a diameter of about
65 micrometres (0.065 millimetres).
Field and her colleagues have tested the idea,
most notably on about 4200 square metres of
North Meadow Lake in Alaska. They have
shown that the microspheres increase albedo
by around 20 per cent and slow the ice melting.
To cover 25,000 square kilometres of the Arctic
with the stuff would cost about $300 million for
the materials alone, says Field. This represents
just 0.7 per cent of summer ice coverage at its
lowest extent on record: 3.4 million square
kilometres in 2012. Yet many questions remain,
not least whether it works on sea ice – so far it
has only been tested on frozen lakes. And what
happens to the beads when ice melts? Some
sink and are incorporated into the mud on the
lake floor, says Field.
There are, however, concerns about the
biological hazards of this approach. Bitz says
she is worried about the ecological impact of
adding millions of tonnes of silica to the Arctic.
“For me this raises a red flag,” she says.
Ken Caldeira, who researches
geoengineering at the Carnegie Institution for
Science in California, has doubts about the
workability of modifying the surface of the
ice – whether by the methods proposed by
Field or Desch – and about whether this could
be an effective tool against climate change.
“I am highly sceptical that this approach will
prove feasible and desirable at scales required
to be climatically substantial,” he says.
For Bitz, Wadhams and several other climate
scientists who spoke to New Scientist, the most
promising potential intervention is one that
doesn’t involve tinkering with the ice directly.
Instead, it entails brightening the clouds over
the Arctic.
The idea dates back to the 1990s, when John
Latham, now at the University of Manchester,
UK, started thinking about ways of limiting
the greenhouse effect by reducing the amount
of sunshine reaching the planet’s surface.
Latham was fascinated by something called
the Twomey effect, which describes how the
amount of solar radiation that clouds reflect
back into space depends on the concentration
of tiny particles around which cloud droplets
form. He realised that you could increase this
concentration over oceans by seeding clouds
with tiny droplets of salt water.
We know from satellite images of ship
tracks – the equivalent of the contrails left by
airplanes – that clouds can be seeded by the
sulphate emissions from ships. Latham and his
colleagues have produced computer models
showing how Arctic sea ice may be restored
by brightening ocean stratocumulus clouds.
These large, rounded clouds are by far the
most common kind seen in the Arctic, and are
usually found in groups covering huge areas.
On paper, it looks promising, but testing it
for real is quite another matter. To do so will
require a system that can spray an ultra-fine
mist of sea water into the lower atmosphere
over a large area of ocean. Stephen Salter, an
engineer at the University of Edinburgh, UK,
has well-advanced plans for this, having
Clouds play a vital part in controlling our
climate. Their reflection of the sun’s rays,
especially at the tropics, is essential for
cooling Earth. But we don’t know how
cloud formation will change as the planet
gets hotter. This means we don’t know
how much warmer Earth will become
for a given increase in carbon dioxide
concentration in the air.
Climate change deniers often point out
that there is too much variability in the
predictions climate models make about
warming. One reason is a lack of certainty
about so-called climate sensitivity. This is
a measure of the amount of warming that
results from a doubling of carbon dioxide
in the atmosphere. In climate models, it
ranges from 2°C to 5°C.
We don’t know if our climate is
particularly sensitive – in that a doubling
of CO₂ gives a correspondingly large
increase in heating – or if it is resilient.
But Tapio Schneider, a climate scientist
at California Institute of Technology in
Pasadena, says evidence from improved
recent climate models points towards
the planet being more sensitive than we
thought, which means we should be very
worried. If it is that sensitive, then we will
get 1°C of additional warming from
adding a mere 70 parts per million or so of
CO₂ to the atmosphere – which would take
about 20 years at the current rate. That
would take us over 2°C of global warming
since pre-industrial times, the level at
which “severe impacts” are expected:
more wildfires, longer periods of drought
in some regions and an increase in the
number and intensity of tropical storms.
Cloud formation is boosted by
atmospheric particles called aerosols,
many of which are pollutants from dirty
industrial processes and fossil fuels. As
these particles have a cooling effect on
the planet, both directly and through their
action on cloud formation, phasing out
their sources will unmask previously
concealed greenhouse gas warming. So to
understand the extra bump of warming
we can expect when the atmosphere gets
cleaner, we need to figure out how clouds
contribute to climate sensitivity.
“Marine cloud-brightening experiments
have the potential to shed light on one of
the most vexing and important questions
in climate science, namely how aerosols
affect clouds,” says Schneider. “It behooves
us to do everything we can to understand
the climate system better, before we try to
manipulate it.”
Predicting warming means deciphering the role of clouds
developed proposals for remotely operated
drone ships able to deliver the spray, which
he presented to the UK government’s
Environmental Audit Committee’s 2017
inquiry into Arctic sustainability. The thing
holding him back is lack of funding.
For the price of Neymar
Shortly after I started corresponding with
Salter, he sent me a photo of Brazilian
footballer Neymar, beaming as his transfer to
Paris St Germain was announced in 2017 at a
cost to the French club of £198 million. Salter’s
point was made clear when he detailed the
costs of his cloud-seeding project. For the price
of Neymar, researchers could conduct all the
preliminary trials and then run an entire fleet
of ships for two years that might start to
restore the damage done to the Arctic.
“Among ideas to prevent Arctic collapse,
the most viable in terms of the scale and
nature of the problem involve increasing the
reflection of sunlight from the atmosphere,”
says Wanser, who is also an adviser to the
University of Washington’s Marine Cloud
Brightening Project. “However, our effective
level of investment in sunlight reflection
is zero. This leaves us with an enormous
exposure to near-term climate risk and
not enough fast-acting options to keep
warming within safe levels.” Several scientific
assessments have identified marine cloud
brightening as one of the most promising
methods to manage sunlight levels, says Rob
Wood at the University of Washington.
We don’t yet know how effective cloud
brightening might be. But there is another
reason to do this research: it could help
solve one of the biggest puzzles related
to how warm our planet could get (see
“Cloudbusting”, left).
In the meantime, the region continues to
turn from white to blue. Wadhams, who has
led 40 expeditions to the Arctic, has seen
enormous change in that time. “When I started
going to the Arctic, you could think of the
whole of the northern hemisphere as a solid
continent,” he says. “Ice connected Eurasia and
North America. But now you have blue ocean.
Physically and psychologically, the world is
fragmented, and I think that is having an
important change in how people think.” ❚
Rowan Hooper (@rowhoop) is head of
features at New Scientist and author
of Superhuman: Life at the extremes
of mental and physical ability
31 August 2019 | New Scientist | 41
Features Big question
Is there
out there?
T IS the biggest question in the universe:
are we alone? Philosophers have
debated the question for millennia.
When 16th-century Italian astronomer and
Dominican friar Giordano Bruno declared that
the cosmos contained “an infinity of worlds of
the same kind as our own”, he was directly
contravening religious dogma. He was later
burned at the stake during the Inquisition, in
part for daring to question Earth’s unique status.
The debate continues, in more restrained
fashion, to this day. For some, the sheer
size of the universe makes it unlikely that
life formed only once. For others, the
remarkable complexity of life on Earth
is testament to its uniqueness.
Until recently, vague philosophical
answers of this kind were the best science
could do. The signs of life were far too
ambiguous to pin down for certain, and
our nearest potentially habitable worlds
were too small and distant to test.
But for the first time in human history we
are reaching the technological sophistication
needed to provide a genuine answer. Powerful
telescopes are letting us study planets in other
solar systems, giving us a glimpse into their
atmospheres and a flavour of what type of life
might be living on their surfaces. At the same
time, improved analysis of our own planet is
allowing us to redefine what life might look
like from afar, and is helping us to distinguish
the signs of a flourishing alien civilisation from
42 | New Scientist | 31 August 2019
the mere geological rumblings of a lifeless
world. With these tools at our disposal,
answers are finally within our grasp.
To understand my optimism, it is worth
revisiting the work of astronomer Frank Drake.
In 1961, Drake devised a formula to estimate
how many advanced civilisations were capable
of signalling their presence in the Milky Way.
His eponymous equation depends on breaking
down that big unknowable quantity into a
number of more tractable ones that can be
multiplied together, such as the number of
stars in the galaxy and the fraction of those
likely to have planets (see “Quiet
neighbourhood”, page 45).
Even with pessimistic values, the existence
of millions of technological civilisations seems
likely. The main bottleneck on that apparent
explosion of life, however, is in Drake’s final
term: the average lifetime of a communicating
civilisation. Humans have been broadcasting
radio signals that escape into space for only
about a century, and, in the current geopolitical
climate, who is to say how many more years
we have left. If you take the pessimistic
assumption that intelligent life destroys itself
rather quickly, the Drake equation suggests
that statistically we are alone in the galaxy.
If intelligent civilisations survive for millions,
or even billions of years, however, then the
Milky Way should be teeming with aliens.
This calls for optimism, but also caution.
After all, if there are millions of alien
After millennia of guesswork, we can
finally start finding out for certain,
says astrobiologist Sarah Rugheimer
civilisations out there, then why haven’t we
seen signs of them already? This seeming
contradiction is sometimes called the Fermi
paradox, after Italian physicist Enrico Fermi,
who gave it its most succinct expression. With
a back-of-the-envelope calculation, he showed
that a single space-faring civilisation could
easily colonise a galaxy within a hundred
million years. Because the universe is
13.8 billion years old, and no interstellar
colonists have yet appeared on our horizon,
Fermi asked: where is everybody?
Radio silence
There are many proposed answers to this
question (see “Solutions to the Fermi paradox”,
page 44). Perhaps, say some, the aliens are
already here, just keeping their identities
secret. Perhaps they are deliberately steering
clear of Earth, treating it as a sort of cosmic
heritage site that deserves their protection.
Or alternatively, there are simply no aliens out
there. As an astrobiologist, I prefer to believe
that aliens are out there; we simply haven’t
communicated with them yet.
It isn’t hard to imagine why this could be the
case. Alien civilisations might well be millions
of years ahead of us in their technological
advancement. Trying to communicate with
them using our primitive technology would
be as absurd as teaching a ladybird to use a
telephone. That hasn’t stopped us trying, of
course, whether by including artefacts, such as
plaques etched with celestial maps and images
of humans, on our long-distance spacecraft or
by broadcasting targeted radio messages into
the depths of space. So far, no reply.
All hope is not lost. The Fermi paradox and
Drake equation specifically deal with the
question of intelligent life, with the ability to
communicate, travel and colonise. But only
a fraction of the life we know of would be
capable of these feats. Today, the vast majority
of Earth’s biosphere consists of microbes.
Single-celled organisms dominated the
planet’s surface for nearly 3 billion years
before multicellular life began. What is more,
microbial cells not only outnumber human
cells on our planet, they even outnumber them
on and in your body. If life exists elsewhere in
the universe, chances are it is microbial.
This means that the first detection of alien
life is unlikely to come from eavesdropping
on an interplanetary conversation. Instead,
we will need to scan the atmosphere of
other planets for familiar molecules that
primitive microbes are likely to emit: as
close as we can get to a fingerprint of life.
31 August 2019 | New Scientist | 43
What does life look like on other planets?
Hear Geraint Lewis speaking at New Scientist Live
Solutions to the
Fermi paradox
In 1950, physicist Enrico Fermi
was having lunch with his
colleagues when he asked a
profound question: where is
everybody? He wasn’t referring
to the emptiness of the
university cafeteria, but why,
if we calculated that the
universe should be filled with
extraterrestrial life, none had as
yet crossed our radar. Over the
decades since then, various
creative solutions to Fermi’s
paradox have been proposed.
This solution remains surprisingly
popular, positing an international
conspiracy to cover up the evidence
of alien contact.
Perhaps aliens have some “prime
directive”, as fictional space explorers
in the TV and film series Star Trek
do, to not interfere with the
development of less advanced
cultures on other worlds.
Or maybe extraterrestrials regard
us as a sort of national park
or zoological garden, watching
our movements but hiding their
The depressing possibility exists
that no advanced civilisation
survives long enough to still be
around when its neighbours are
thriving. This idea is called the
Great Filter. We may have already
unknowingly passed through the
filter unscathed, or it may be
looming, in which case threats
such as nuclear war and climate
change might spell our doom.
Might the simplest answer
be the best, after all?
44 | New Scientist | 31 August 2019
An obvious place to start is with our own
planet. If alien astronomers were observing
Earth from a remote star system, would
anything about it grab their attention?
Compared with our rocky neighbours Mars,
Venus and Mercury, the distinctive mix of
oxygen and methane in Earth’s atmosphere
would be sure to trigger interest. Oxygen
makes up 21 per cent of the atmosphere
now and is entirely due to life, entering the
atmosphere from photosynthetic bacteria
and plants that convert sunlight into energy.
We aren’t sure when exactly oxygenic
photosynthesis evolved, but there are
clear signs that our atmosphere filled
with oxygen 2.33 billion years ago.
Methanogens, the microbes that
produce methane, existed even earlier.
Despite the biological origins of both
gases, neither on its own is a sure sign of life.
Methane, for example, is also produced by
volcanoes and hydrothermal vents, although
methane with an organic origin has a higher
carbon-12 to carbon-13 isotope ratio. Oxygen
could be formed when radiation from an active
star splits molecules of water into hydrogen
and oxygen, with the lighter hydrogen
escaping from the planet’s atmosphere. In
combination, however, methane and oxygen
tell a story of a planet swarming with life.
In the 1960s, astronomers realised that the
existence of each gas was fatal to the other.
Without large quantities of both oxygen and
methane being continuously pumped into
the atmosphere, these gases would quickly
react and destroy each other. Individually
you might expect a lifeless planet to contain
either oxygen or methane. But geology alone
doesn’t provide a way to maintain both.
This means that finding oxygen and
methane coexisting in appreciable quantities
on a distant planet is a pretty good indicator
of life. What’s more, life on Earth produces
thousands of other molecular gases that
seem to be unique. Methyl chloride, dimethyl
sulphide and nitrous oxide have all been
proposed as promising biosignature targets.
What if our search for all of these gases
comes up empty? Does that mean a planet is
an arid ball of rock? Not necessarily. Life on a
distant world may be totally different to that
on Earth. It could be hiding under the surface,
within solid rock or in hidden seas, where it
would be effectively invisible. More radical
alternatives are also possible. It could be based
on silicon, for example, rather than carbon, or
run on unknown metabolisms that use a liquid
other than water. For these types of weird life,
synthetic biology and research into alternative
biochemistries could help us understand what
unique chemicals to look for.
Sara Seager at the Massachusetts Institute
of Technology is trying to tackle this problem,
working her way through all the molecules
whose presence might indicate the existence
of life. One of my favourite ideas comes from
another MIT researcher, Clara Sousa-Silva,
who says we should look for phosphine as a
sign of life. Phosphine is a gaseous compound
of phosphorus and hydrogen that is produced
“Finding no life elsewhere may lead us
to take better care of our own world”
Quiet neighbourhood
pl be
an r o
et f h
sp a
ac er s ita
th tion tar le
at o
de f t
ve ho
lo se
w tion life plan
ith o
i n f th
ig e
e p
de tion nt lan
te o
ct f c fe ts
ab iv
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ol th
og a
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l s lea
ig se
Frank Drake’s 1961 equation remains the best method to get a rough sense of how many detectable alien
civilisations should exist within our galaxy (N). According to the latest data, that number is somewhere
between 1 – our lonely selves – and an impressive 4 billion
N = R* x fp x ne x fl
on Earth by anaerobic microbes, which don’t
rely on oxygen to survive. Not only would it
be relatively easy to detect in an exoplanet’s
atmosphere, but it is the simplest gas that
can’t be produced by any natural processes
we know of. Detecting phosphine, in other
words, could indicate an anaerobic biosphere.
If coming up with such hypotheses seems
challenging, putting them to the test is
something else entirely. The first step is to
identify candidate exoplanets: those with the
right temperatures to nurture the complex
chemistry needed to sustain life. At present,
finding worlds beyond our solar system is
usually done by looking for the slight dimming
that happens when a planet crosses in front of
its star. It is a process hundreds of times more
difficult than spotting a firefly crossing a
searchlight on the other side of the Atlantic.
This detection method also opens the door
to sensing different types of molecules in the
atmosphere of a temperate and rocky planet.
For example, when light from a star passes
through the air cloaking such worlds it can
reveal the composition of that air. Different
fi x fc x L
molecules respond to different wavelengths
of light, and by separating the light we collect
in our telescope into different wavelengths,
we could see the telltale spectra, or light signals,
produced by substances such as oxygen,
ozone, methane, water and carbon dioxide.
What makes it such an exciting time to work
in this field is the number of missions being
developed to perform this task. The first
of these will be NASA’s James Webb Space
Telescope, scheduled to launch in 2021. This
will be our first hope at identifying molecules
in the atmosphere of a habitable exoplanet.
ARIEL, a European Space Agency mission due
to launch in 2028, will continue this effort.
Another promising technique involves
using large ground-based telescopes to do
the same thing. These include the European
Southern Observatory’s Extremely Large
Telescope, currently being built in Chile and
due to start working in 2025. Observing planet
atmospheres from Earth’s surface is difficult
because you must first remove our planet’s
atmosphere from the signal. Next-generation
ground observatories will be able to do just
that by subtracting its effects from the light
entering the telescope. This detailed technique
can even allow us to distinguish isotopes
on other worlds, subtly different versions
of the same atoms that differ only by the
presence of a single neutron in their nuclei.
That is something I never dreamed would
be possible in my lifetime.
For all the excitement surrounding far-flung
planets, perhaps the first successful detection
of extraterrestrial life will happen closer to
home. Certainly, other places in our solar
system have conditions suitable for life as
we know it, such as in the liquid water ocean
hidden beneath a thick ice layer on Jupiter’s
moon Europa or in the subsurface water on
Mars. Alternatively, some have suggested that
life could reside on Saturn’s moon Titan,
swimming in its lakes of liquid methane.
Whatever we find on these nearby worlds,
I am confident life exists elsewhere in the
universe. But confidence isn’t enough. Over
the next few years, our searches are going to
become more accurate, more thorough and
capable of looking further than before.
The answers we find stand to fundamentally
shift our understanding of the universe and
our place in it. As the science fiction writer
Arthur C. Clarke put it: “Two possibilities
exist: either we are alone in the universe
or we are not. Both are equally terrifying.”
To my mind, finding alien life would humble
our apparently exalted status in the cosmos.
We would be just one more example of life as
a planetary process, crystallising out of the
molecules that make up our universe.
Searching widely and finding nothing would
be equally sobering, however, indicating that
even in environments we think of as habitable,
the chasm between chemistry and simple life
is vast. Hopefully, such an appreciation of
life’s rarity would lead us to protect all forms
of existence on our own world, reminding us
that Earth is the only home we have.
The next two decades will witness a
revolution in exoplanetary science. We have
already found dozens of potentially habitable
worlds and the next technological advancement
in observations will be able to detect potential
biosignatures in their atmospheres. Now we
need to watch – and wait. ❚
Sarah Rugheimer is an
astrobiologist at the
University of Oxford, UK
31 August 2019 | New Scientist | 45
Recruitment advertising
Tel +1 617-283-3213
Email nssales@newscientist.com
Vascular smooth muscle and
endothelial cell ion channels
Postdoctoral position immediately available
to study physiological functions and
pathological alterations in arterial smooth
muscle and endothelial cell ion channels.
Projects include studying blood pressure
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Bring your
career to life
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and discover the latest opportunities
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curriculum vitae and names and addresses
46 | New Scientist | 31 August 2019
Assistant Professor of Chemistry
The University of Chicago: Physical Sciences Division: Department of
Postdoctoral Fellowships in Cutaneous Biology
NIH T32-funded postdoctoral fellowships are available in the Department of Dermatology
Information about the Training Program is available at:
Research descriptions for U-M faculty are available online at:
residents are eligible to apply
Please send CV and references to::
Chicago, Illinois
The Department of Chemistry at The University of Chicago invites applications
for the position of Assistant Professor of Chemistry in all areas of chemistry.
Applicants must apply online at apply.interfolio.com/66199 and upload a cover
letter, a curriculum vitae with a list of publications, a succinct outline of research
plans and a one page teaching statement. In your cover letter, please specify
one sub-discipline that best represents your research interests (inorganic,
materials, organic, physical, theoretical or chemical biology). In addition, three
reference letters are required.
At the time of hire the successful candidate must have completed all
other departments are possible.
Application Instructions
Review of applications will begin on October 07, 2019 and will continue until all
Apply to: apply.interfolio.com/66199
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religion, sex, sexual orientation, gender identity, national or ethnic origin, age,
status as an individual with a disability, protected veteran status, genetic
information, or other protected classes under the law. For additional information
please see the University’s Notice of Nondiscrimination.
application process should call 773-702-1032 or email equalopportunity@
uchicago.edu with their request.
NRC Research Associateship Programs
The National Academy of Sciences, Engineering, and Medicine offers postdoctoral and senior research awards on
behalf of 23 U.S. federal research agencies and affiliated institutions with facilities at over 100 locations throughout the
U.S. and abroad.
We are actively seeking highly qualified candidates including recent doctoral recipients and senior researchers.
Applications are accepted during 4 annual review cycles (with deadlines of February 1, May 1, August 1, November 1).
Interested candidates should apply online http://sites.nationalacademies.org/PGA/RAP/PGA_046398
Awardees have the opportunity to:
conduct independent research in an area compatible with the interests of the sponsoring laboratory
devote full-time effort to research and publication
access the excellent and often unique facilities of the federal research enterprise
collaborate with leading scientists and engineers at the sponsoring laboratories
Benefits of an NRC Research Associateship award include:
1 year award, renewable for up to 3 years
Stipend ranging from $45,000 to $80,000, higher for senior researchers
Health insurance, relocation benefits, and professional travel allowance
Applicants should hold, or anticipate receiving, an earned doctorate in science or engineering. Degrees from universities
abroad should be equivalent in training and research experience to a degree from a U.S. institution. Some awards are
open to foreign nationals as well as to U.S. citizens and permanent residents.
The National Academies of Sciences, Engineering, and Medicine’s Fellowships Office has conducted the NRC Research
Associateship Programs in cooperation with sponsoring federal laboratories and other research organizations approved
for participation since 1954. Through national competitions, the Fellowships Office recommends and makes NRC
Research Associateship awards to outstanding postdoctoral and senior scientists and engineers for tenure as guest
researchers at participating laboratories. A limited number of opportunities are available for support of graduate
students in select fields.
31 August 2019 | New Scientist | 47
Join us in Anaheim this November!
NOVEMBER 13-16, 2019
Recipient of the
2019 AIMBE Excellence in STEM Education Award
The Annual Biomedical Research Conference for Minority Students (ABRCMS)
is a must-attend event bringing together one of the largest communities of
underrepresented minorities in STEM fields.
This award-winning conference gathers dynamic undergraduate students, and
the research faculty and program directors who mentor them, for four-days
of learning, sharing, and networking. From poster presentations to scientific
and professional development sessions and exhibitor showcases, ABRCMS is a
robust event guaranteed to leave you feeling inspired.
Mark your calendar and plan to join us
November 13-16, 2019, in Anaheim, CA!
Managed by:
Funded by:
Fellowships for Postdoctoral Scholars
accepted from doctoral recipients with research interests associated with the following:
Departments - Applicants who wish to conduct
research on topics of general interest to one or more of the
departments are encouraged to apply. Interdepartmental
research, including with the Marine Policy Center, is also
encouraged. The Departments are:
ƒApplied Ocean Physics & Engineering
ƒGeology & Geophysics
ƒMarine Chemistry & Geochemistry
ƒPhysical Oceanography
A joint USGS/WHOI aaward will be given to a
postdoc whose research is in an area of common interest
between USGS and WHOI Scientific Staff. The individual
will interact with both USGS and WHOI based advisors on
their research.
Center (OBSIC) will award a fellowship for research on
the earth’s internal structure and its dynamic processes
seismograph data, including the development and/
measurements and oceanographic
within this broad scope. Award
recipients may be advised by
Departments as well
as the USGS, or a
primary emphasis placed on research promise. Scholarships
of $61,200 per year, a health and welfare allowance and a
is encouraged. olrѴ;|;7-rrѴb1-ঞomvl†v|0;u;1;bˆ;70‹
1|o0;uƐƔķƑƏƐƖ for the 2020/2021 appointments. Awards
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ঞl;-[;u-m†-u‹ƐķƑƏƑƏ-m70;=ou; ;1;l0;uƐķƑƏƑƏĺ
forms as well as links to the individual Departments and their
research themes may be obtained through the Academic
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The back pages
Quick crossword,
a riddle of ages
and the quiz p52
Sexy pavement lichen
and a robot priest: the
week in weird p53
Picture of the week
Your photos based
on a weekly theme:
first up, Mars p53
Almost the last word
Readers explain why
water hydrates and
dogs roll over p54
The Q&A
Niamh Nic Daeid on
a paradigm shift in
forensic science p56
How to be a maker 2 Week 8
How’s the weather?
With two micro:bits you can make a mini weather station that
sends you up-to-the-minute reports, says Hannah Joshua
New stuff you need
Second micro:bit
and battery
DHT11 environmental
For next week
Large plastic drinks bottle
Zip ties
Servo motor
Nuts (the edible kind)
Next in the series
1 Moisture-sensing plant
2 Moisture and temperaturesensing plant
3 Plant auto-waterer
4 Tweeting wildlife cam
5 Pest scarer
6 BBQ thermometer
7 Rain alarm
8 Mini weather station
9 Remote controlled
pest-proof bird
feeder part 1
10 Bird feeder part 2
Hannah Joshua is a science
writer and maker based in
London. You can follow her
on Twitter @hannahmakes
LAST week it was rain. This
week, our mini weather station
will measure temperature and
humidity. And by using a second
BBC micro:bit, we can get the
readings before heading outside.
First, we need a DHT11 sensor,
and to check whether it works
using one micro:bit. To do this, we
must teach the MakeCode editor
new tricks. Go to “Extensions”,
type in “DHT11” and click on the
DHT11/DHT22 result.
Under the new menu option,
select the block that is five lines
tall and clip it into forever. This
one communicates with the
sensor. The default settings are
fine. Under that block, clip two
“show number” blocks from
“Basic” and clip into these two
“Read humidity” blocks from the
“DHT11/DHT22” menu, using the
drop-down to change the first to
“Read temperature”. Lastly, add a
“pause” from “Basic” to “on start”
to give this sensor a moment to
fire up before we start quizzing it.
Connect the sensor’s Vcc
connection to the micro:bit’s 3V
pin, its ground to ground and out
to pin 0. Attach the battery and
check the readings seem sensible
for temperature and humidity.
Now, we can transmit the data
to another micro:bit via radio. In
your program, replace the “show
number” blocks with two “radio
send value name = 0” blocks from
the “Radio” menu. Where these
say “0”, clip two “round” blocks
from “Math”, then into the “0” of
each clip a “Read humidity” block
from “DHT11/DHT22”, using the
drop-down to change the first one
Make online
Projects so far and a full list of kit required are at
newscientist.com/maker Email: maker@newscientist.com
to “Read temperature”. In the first
“name” oval, enter “T:” and put
“H:” in the second. Then, clip a
2-second “pause” between the
blocks and another “pause” after.
The second “pause” will determine
how often this micro:bit sends
data. I went for 10 seconds.
Finally, take “radio set group 1”
from “Radio” and clip it into “on
start”. The radio group establishes
a comms channel so micro:bits
using the same one can recognise
messages from each other.
Now for the receiver. Start a
new program and add the same
“radio set group 1” to “on start”.
Next, grab an “on radio received
name value” from “Radio”. Into
this, clip a “show string” block
and a “show number” block from
“Basic”. Then, click and drag the
“name” oval from the top of the
“on radio received” block and drop
it into your “show string” block.
Do a similar thing for “value” and
“show number”. This code will
make your receiver micro:bit
show “T:”, followed by the
temperature, and “H:” followed
by the humidity on the screen.
Now, stash your transmitter in
a waterproof container and poke
a hole so air can get in, but the
electronics are safe. The radio
range is up to 70 metres in an open
area without interference, so get
creative with the placement! ❚
31 August 2019 | New Scientist | 51
The back pages Puzzles
Quick crossword #39 Set by Richard Smyth
1 Nihonium, Tennessine,
Oganesson – what fourth
name is missing from
this list?
#19 The vicar’s age
3 The ICZN, based in
do what?
Puzzle set by Zoe Mensch
2 9,192,631,770 what of
what equals what?
Quick quiz #18
4 A golfball-sized lump of
90 per cent platinum and
10 per cent iridium (by
mass) fulfilled what function
until 2019?
5 FlyBase collates genetic
information concerning
which fast-breeding
organism beloved
of biologists?
A bishop visited his friend the vicar on
her birthday. Knowing the bishop liked
number puzzles, the vicar told him about
a family that had just joined her church.
“If you multiply their three ages
together, you get 2450, and if you add
their ages together, you get your own age,
your grace.”
The bishop, after some thought, said:
“I can’t be certain how old everyone in the
family is.”
The vicar responded: “I am older than
everyone in that family.”
The bishop could then tell how old
everyone was.
How old was the vicar on that day?
Answer next week
Answers below
16 Marriage within a social
or ethnic group (8)
21 Harvey ___, rubber
tyre pioneer (9)
24 Condition caused by
YLWDPLQ'GHILFLHQF\ 25 Of algebra, functions or
variables, relating to a
19th-century logician (7)
phenomenon (2,4)
1 B
species (5)
launched in 2006 (7)
essayist (7,3,5)
5 Friedrich ___, inventor
of a scale of mineral
hardness (4)
6 Air sacs in the lungs (7)
7 õ+DFNWLYLVWöJURXS 10 Fastener patented
in 1849 (6,3)
13 2011 science fiction
Gyllenhaal (6,4)
14 Cretaceous clay found
in Wyoming (9)
17 Waterproof garment (7)
52 | New Scientist | 31 August 2019
Crossword #13
#18 Cable on the moon
A power cable buried in a 1-metre deep
trench encircling the moon’s equator will
only be about 6 metres shorter than if it was
laid on the surface.
8 Generation Gap, 96KDUG
10 Trailer, 12 Median,
136WUHVV16 Chimera,
18 Needs, 20 Quadrilateral,
22(SR[\23 Cold War
DOWN 1 Bogus, 2 Lanyard,
3 Irradiate, 4 Rotate, 5 UFO,
6 Bagel, 7 Amperes,
11 Antenatal, 12 Macaque,
14 Eyebrow, 15 Garlic,
17 Imago, 196RODU21 Ray
Quick quiz #18
added to the periodic table by the
Applied Chemistry in 2016.
2 The International Bureau of
9,192,631,770 oscillations of
the hyperfine ground states of the
caesium-133 atom = 1 second.
3 The International Commission
on Zoological Nomenclature and
the International Association for
animal and plant names.
4 It was the international
replaced it with a standard based
5 The fruit fly Drosophila
1 Intelligence assessment,
purportedly (2,4)
4 Antelope; Chevrolet (6)
8 6SOLWVKDUHG 9 ^ (7)
11 Term used to describe
the technological
revolution by Harold
Wilson in 1963 (5,4)
12 Abnormal growth
projecting from a
mucous membrane (5)
14 B (5)
15 3HUKDSV RU The radius of the moon (R) at the equator is
1,738,100 metres, but you don’t actually
need that figure to answer this question.
The length of cable on the surface is given
Burying the cable 1 metre down reduces
the radius to R-1. The new cable length is
cable length on the surface gives a difference
shorter than one on the surface.
Get in touch
Email us at
The back pages Feedback
Taking a liking to lichen
If you happen to be in New Zealand
and are unnerved by that man
over there apparently licking
the pavement, don’t be alarmed.
He is probably just after his fill of
Xanthoparmelia scabrosa, a grey,
leafy lichen commonly found
on Kiwi roads and sidewalks.
It contains a chemical somewhat
similar to the active ingredient in
Viagra, gaining it the soubriquet
“sexy pavement lichen”.
Online marketplaces have taken
to selling X. scabrosa by the kilo as
a herbal alternative to the little
blue pills. Now Kiwi news outlet
Newsroom relays warnings from
local researchers against likin’ the
lichen. Those hoping it will give
them more lead in their pencil may
get more than they bargain for: the
urban pavements where the lichen
grow infuse them with high levels
of lead and other heavy metals,
including cadmium, mercury and
Perhaps it is fortunate, then,
that an investigation by the US Food
and Drugs Administration into one
online batch of X. scabrosa found it
was 20 per cent grass clippings and
80 per cent ground-up Viagra. What
dodgy online herbal remedies lack
in authenticity, they may make up
for in efficacy. Besides, nothing
quite kills the mood like popping
out to lick the street.
Deus Ex Machina
A 400-year-old temple in Japan
has unveiled its latest priest:
a robot modelled on Kannon
Bodhisattva, the Buddhist deity
of mercy. The $1 million android,
named Mindar, leads services at
Kodaiji temple in Kyoto, relaying
and explaining wisdoms
contained in the Heart Sutra.
It isn’t the first time holy words
have come from robot mouths.
Readers may recall that Pepper –
a child-sized android that has held
down more jobs than Barbie – also
had a stint presiding over
Buddhist funerals back in 2018.
What should we draw from this
about the essence of Buddhism,
except that creeping automation
comes for all, and the holy men
won’t be spared? If you pass a
saffron-robed man on the street,
begging bowl in hand, be kind.
He might not even have a job
any more.
Picture of the week Mars
Rabbit run
Further to the question of
whether nematode worms read
New Scientist (10 August), Peter
Duffell writes: “On a recent trip
to Northumberland we saw a sign
in one of the gardens we visited
“If only rabbits and hares are
required to shut the gate, what
do the rest of us do?” asks Peter.
“If we leave them open, do the
rabbits and hares get the blame?”
Feedback is unsure: rabbits
that can read signs can probably
type, too. You wouldn’t want
to risk online shaming by
Northumberland’s literate
Double trouble
Let it not be said that Brazil’s
president Jair Bolsonaro isn’t
environmentally conscious.
Yes, he has threatened protections
of indigenous land rights and
opened up the Amazon to logging
and mining. Yes, he fired the
director of Brazil’s National Space
and Research Institute after it
revealed the extent of recent
But he has a plan. Questioned
on his environmental record, he
replied: “It’s enough to eat a little
less. You talk about environmental
pollution. It’s enough to poop
every other day. That will be better
for the whole world.”
As green policies go, two days
between number twos is a novel
one. We’ll resist the temptation
to say it’s all going down the pan.
Given the boost Bolsonaro’s
policies are giving to consumption
and exploitation, Feedback thinks
Brazil’s green activists can be
forgiven for thinking he is the
one full of crap.
To give you a taste of our new picture of the week slot, here is New Scientist’s
head of features, Rowan Hooper, with a full-size replica of the Curiosity rover.
While its twin is on Mars, this one is at the University of Arizona.
The next theme is Alexander von Humboldt, in celebration of the
250th anniversary of the naturalist’s birth. Email us your related
photos to readerpics@newscientist.com by Tuesday 3 September.
Terms and conditions at newscientist.com/pictureoftheweek-terms
Noms de flume
Wonder weed
Such themes lead us, with terrible
inevitability, to this week’s dose
of nominative determinism. In
Adelaide, Australia, Alan Moskwa
reveals that a story in The Advertiser
on the city’s expanding waistlines
has provoked a letter in reply
suggesting “toilet bowls and seats
should be strengthened, enlarged”
and generally made taller and
wider. The correspondent’s name?
Neil Longbottom.
Meanwhile, Peter Jung is
delighted to discover that the
head of coastal research at Monash
University in Melbourne is none
other than Ruth Reef.
Visiting a chiropodist’s surgery in
Greenock, UK, Bill McMillan spies
a poster proclaiming that cannabis
oil can help with PTSD, epilepsy,
Crohn’s disease, cancer, psoriasis,
Dravet syndrome “and many
more conditions”.
Only two weeks ago, this
esteemed organ raised an eyebrow
at the wondrous variety of claims
made for weed’s curative powers
(17 August, p 20). But Bill is most
perplexed by an omission. “It
seems the oil can cure anything
except foot and toenail issues,”
he says. Well, the chiropodists
wouldn’t tell you if it did. ❚
Got a story for Feedback?
Send it to New Scientist, 25 Bedford Street,
London WC2E 9ES or you can email us at
31 August 2019 | New Scientist | 53
The back pages Almost the last word
Why don’t blue
highlighters look as bright
as the other colours?
Seven litres a day
How does water hydrate us?
If we drink a lot of it we only
pass it as excess waste.
Andrew Sanderson
Spennymoor, County Durham, UK
We lose water in four principal
ways: in urine, sweat, breath
and faeces. This doesn’t include
minor losses such as in tears
and spitting. We gain water by
drinking, and by breaking down
food during metabolism into
carbon dioxide and water.
Sweat, breath and faeces stay at
the same concentration, so the
main control of body fluid content
is via our kidneys. Their activity
is controlled by a molecule known
as vasopressin or antidiuretic
hormone, which is secreted by
the pituitary gland. This is
regulated by an area of the brain
called the hypothalamus, which
contains receptors sensitive to
the blood’s concentration of
sodium and other substances.
The kidneys are the main way
for us to excrete salts. If you eat
a lot of salt, your kidneys will
increase the concentration of
the urine up to their maximum
ability. Past this, the volume will
increase. If you drink a lot of water,
54 | New Scientist | 31 August 2019
Why do dogs and horses roll on
their backs when happy?
Eleanor Horton,
Canterbury, Kent, UK
Breaking down food – and our
metabolism in general – generates
waste. This needs to be removed
or it would damage the body.
Water is the solvent for these
waste products – it dissolves them
and allows them to pass out of the
body as urine, as well as in sweat.
Urine is produced in the kidneys
and consists of urea and other
waste products dissolved in water.
We need to drink more water to
replenish the fluid that leaves the
body this way.
When you are dehydrated, your
urine will be dark yellow. This is
because there isn’t enough water
in your system to dilute the urea
sufficiently. Water itself is not a
waste product – it is a mechanism
by which the body removes waste.
Roll of honour
This week’s new questions
In the ink Why do blue highlighter markers never seem to
have the high luminosity of pink, yellow, orange and light
green highlighters? Ana Beard, London, UK
Once upon a time Why does my brain like fictional stories?
Shvets Roman, Moscow, Russia
Run the world If the world’s population all met in one place
and all ran in the same direction, would this affect Earth’s
rotation? Neil Edwards, Guildford, Surrey, UK
urine concentration falls and
volume increases. The more
you exercise and sweat, the
more salts you lose, because
sweat can’t be concentrated,
hence the marketable value of
sports drinks. The amount you
need to drink is unique to you.
Linked to the hydration sensors
are the thirst parts of your brain.
If you feel thirsty, then drink
water. Otherwise, keep someone
else happy and rich by buying
their fluid replacement and by
all means carry a bottle with you
to prove that selective advertising
has an effect on you.
Brian Pollard
North Hill, Cornwall, UK
The human body is made up
mainly of water, and our
physiology operates to keep
within about a litre of the 45 or so
litres in an average-sized person.
The way it does this is by
regulating the feeling of thirst.
When the fluid level starts to get
low, your body makes you feel
thirsty. You drink, and the body’s
regulatory system works out how
much you should drink to restore
the balance to be within required
limits. When you have drunk
enough, you feel sated and stop
drinking. This system is
remarkably efficient.
It takes several hours for the
fluid levels in the body to respond
to the liquid you have drunk, but
the regulatory system works well
enough most of the time to keep
the body’s fluid content within
its typical parameters.
If you lose a lot of water
quickly, on a very hot day for
example, you may lose too
much, and then you become
dehydrated, and it feels
unpleasant. The unpleasant
feeling is your body requesting
an urgent ingestion of liquid.
David Muir
Edinburgh, UK
Horses roll and writhe on their
backs not because they are happy
but because they want to get rid
of an itchy irritation. They could
be trying to get rid of their winter
coat, which makes them sweaty
in the summer. If they are being
bothered by biting insects, then
rolling in mud, or even dust,
affords some protection.
Dogs are different. A very
relaxed dog will lie on its back with
its vulnerable abdomen exposed.
On the other hand, a dog that is
frightened may roll over as a sign
of submission and thus avoid
attack by another dog.
Some dogs retain their
evolutionary urge to roll in other
animals’ excreta, such as fox
faeces, to disguise their own scent.
This seems to make dogs happy
and their owners very unhappy.
Tony Holkham
Boncath, Pembrokeshire, UK
Horses, and many other animals,
roll to rid themselves of irritation
or parasites that they can’t reach
with their mouths or feet. It is
necessary, but leaves the animal
vulnerable for a short time.
Dogs roll for this reason too,
especially because many modern
breeds are unable to groom
themselves effectively. They
also do it to submit to another
member of the pack and, in
domesticated dogs at least,
because they love to have their
belly rubbed. My Jack Russell
Sparky would probably put this
last reason at the top of the list. ❚
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The back pages The Q&A
As a forensic scientist, Niamh Nic Daeid does
research that helps justice be done – from how
fires start to how DNA transfers between objects
As a child, what did you want to do
when you grew up?
My parents were practical scientists, and they
used their skills to solve real-world problems.
Partly as a consequence of that, my overriding
desire was to make a difference when I grew up.
Explain what you do in one easy paragraph.
I lead a team of people from different scientific,
statistical and science communication
backgrounds and we try to address some of the
fundamental challenges in how science is used in
the justice system. We work with police,
researchers, lawyers, judges and the public. I also
do forensic casework – my area of expertise is in
investigating how and where fires start.
What’s the most exciting thing you’re
working on right now?
We are working on the development of a global
citizen science project that will help forensic
scientists understand how materials transfer
between surfaces and then persist on the surface
they have transferred to. We have designed
and tested universal experiments to build
databases that will address these questions and
will launch these globally in 2020. These are
profoundly important issues that help us
explain the relevance and weight of forensic
evidence to our courts.
If you could send a message back to
yourself as a kid, what would you say?
Work harder than everyone else and don’t be
afraid to think differently.
Were you good at science at school?
Yes – and maths and woodwork, which is
always a useful skill to have.
What achievement or discovery are you
most proud of?
Proving that conventional smoke alarms don’t
wake children and then finding a sound that does.
It sounds like a truck reversing, that intermittent
beeping noise, followed by a female voice saying
“get up, the house is on fire”. Each sound is played
for 10 seconds, repetitively. Most children wake
with either the first beeping tone or when they
hear the voice for the first time.
56 | New Scientist | 31 August 2019
How has your field of study changed in
the time you have been working in it?
We have been at the centre of a paradigm shift
in forensic science. The situation before was
that the only time judges and forensic scientists
spoke to each other was in the courtroom.
Now, the judiciary and forensic scientists work
together. We speak about science in informal
ways, exploring each other’s questions and
perspectives, to gather a collective understanding
of what science can answer and what it can not.
Do you have an unexpected hobby,
and if so, please will you tell us about it?
Not really – I am a workaholic.
How useful will your skills be after
the apocalypse?
I can make things out of wood and I can set a fire
almost anywhere – two of the essential skills for
building a shelter and keeping toasty warm.
If you could have a long conversation
with any scientist living or dead,
who would it be?
One is Michael Faraday, who wrote
The Chemical History of a Candle and instigated
the Royal Institution’s Christmas lecture series.
Another is Florence Nightingale, who was the
first female member of the Royal Statistical
Society and made good use of infographics.
OK one last thing: tell us something that
will blow our minds…
We have very little understanding of how trace
materials, such as DNA, transfer and persist from
one surface to the next. If someone picks up a
glass that you have handled and then they pick up
a weapon and assault someone, your DNA could
transfer to that weapon even though you have
never directly touched it. We are undertaking
research to understand whether this can happen
and in what circumstances. ❚
Niamh Nic Daeid is professor of forensic science
and director of the Leverhulme Research Centre for
Forensic Science at the University of Dundee, UK
“Your DNA could
transfer to a
weapon even
though you have
never directly
touched it”
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