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This week’s issue
On the 10 Coronavirus 32 Features
cover myths busted
Why the virus isn’t from “A forgotten
38 Evolution special issue a lab, and why you didn’t type of
The changing face of our have it in December nuclear
greatest theory of nature power
32 Nuclear batteries could be safe,
Vol 247 No 3301 The forgotten power powerful and
Cover image: Tim McDonagh source that could fuel long-lasting”
an energy revolution
Features
21 Pivot to Venus
13 Halloween allergies 32 Nuclear batteries
18 Fish that grab crabs A forgotten kind of nuclear
51 The science of gardening power could create amazingly
19 Giraffes hit by lightning long-lasting batteries
News News GERRY ELLIS/MINDEN/NATUREPL.COM 38 Evolving evolution
Charles Darwin laid the
8 Testing times 16 ’Massive failure’ World falls short on biodiversity targets foundations of evolution.
How the UK could get a Then came genes, which
grip on coronavirus testing explained how it worked.
Now our greatest theory
12 Venus fly-by of nature is changing
The BepiColombo probe will once again
have a chance to hunt for life
The back pages
18 Apple Watch
The latest Apple gadget can 51 The science of gardening
monitor your blood oxygen Green your home by growing ivy
level, but why?
52 Puzzles
Views A quick crossword, a page-count
conundrum and the quiz
21 Comment
Let’s focus on Venus and 54 Almost the last word
search for life, says Peter Gao How people in the Arctic
learned to cope with little sun
22 The columnist
Annalee Newitz takes the long 56 Feedback
view amid a year of disasters The weird science that won
this year’s Ig Nobel prizes
24 Aperture
California’s wildfires 56 Twisteddoodles
caught on camera for New Scientist
Picturing the lighter side of life
26 Letters
Views on the “fuzzi-verse”, 26 September 2020 | New Scientist | 1
the pandemic and much more
28 Culture
Incredible stories of the
human brain’s ability to adapt
Elsewhere A note from
on New Scientist the editor
Virtual events Virtual events
How to keep your FRANZ12/GETTY IMAGES/ISTOCKPHOTO THE sharp-eyed among you
brain healthy (even will have already noticed a few
in a pandemic) changes to the Back Pages
section of the magazine.
Psychologist Kimberley Wilson
reveals how lifestyle habits can In the last issue we welcomed
make a difference. Discover the back Abigail Beall’s Stargazing
science behind this and get at home column, in which she
practical advice. Thursday explained how to see a SpaceX
15 October at 6pm BST/ Starlink satellite. Her column
1pm EDT/on-demand. will now appear every four
weeks, on a rotation with three
newscientist.com/events other columns, two new ones
and another returning favourite.
Podcasts Get some headspace Expert tips on keeping your brain healthy
This week it’s the turn of
Weekly Video a fresh offering, Science of
gardening, written by medical
The race to find life on Venus; reporter/allotmenteer Clare
coronavirus set to claim the lives Wilson. She begins with a trend
of 1 million people; the extinction in architecture to cover walls
crisis; how the brain slows time. with plants to help insulate
buildings, soak up rain and give
newscientist.com/podcasts wildlife more space. However,
this usually requires complex
Newsletter Down in the dust Sam Wong explains how rovers hunt life on Mars structures to support the soil.
There is another way to get
Health Check Podcasts these benefits, though, which
Clare tells you about on page 51.
Our free newsletter rounds up health
and fitness news. This week: what Next week will be Layal
the pandemic’s future may look like. Liverpool’s turn with another
newscientist.com/ new column, Citizen Science,
sign-up/health in which she investigates the
most interesting collaborative
Video science projects and explains
how to get involved. Her first
Life on Mars? instalment will look at a scheme
that has recruited millions of
This week’s Science with Sam people to help us fight covid-19.
explains how Perseverance, NASA’s
latest Mars rover, will look for signs The final part of the quartet
of ancient life. will be a return of Sam Wong’s
youtube.com/newscientist very popular Science of cooking.
We hope you enjoy!
Online YANDONG LIU /ALAMY
Emily Wilson
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2 | New Scientist | 26 September 2020
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The leader
Darwin was right
The glorious theory of evolution by natural selection has seen off all comers
THE theory of evolution is one of the core of the theory, yet it has constantly what emerges is Evolution 3.0, or
greatest accomplishments of the accommodated new knowledge. This merely Modern Synthesis 1.1. If nothing
human intellect. Some might argue happened most conspicuously about else, the flurry of activity is proof that
that it is the greatest, although quantum a century ago, when the new science evolution – and hence biological
theory or relativity would have their of genetics was melded with natural science – is a vibrant, living-and-
supporters too. But in the biological selection to create what became breathing entity still in its prime.
sciences, it stands unrivalled. It is no less known as the “modern synthesis”.
than the grand unified theory of life. Evolution has also achieved
“The voices of evolution’s something that is arguably more
It is also a theory in the truest sense detractors have largely fallen important: it has seen off its culture
of the word: an interlocking and silent, worn down by the warrior detractors. A decade ago, it
consistent system of empirical patient drumbeat of reason” was on the front line of the war on
observations and testable hypotheses science, under attack from creationism
that has never failed scrutiny. Nothing Today, we are arguably in the midst of and its pseudoscientific alter ego,
has even been discovered that falsifies another upgrade. Over the past 30 years, intelligent design. Those voices have
any part of it, despite strenuous efforts discoveries in developmental biology, now largely fallen silent, worn down
by detractors. It all stacks up. epigenetics and elsewhere have needed by the patient drumbeat of reason.
to be brought under the wing of
Yet we should resist the temptation to evolution. As our special report on page Sadly, that remains an isolated
think that evolution is carved in tablets 38 shows, they largely have been. Only victory in the wider anti-science culture
of stone. The radical but irresistible ideas hindsight will be able to judge whether war. But it shows that victories aren’t
put forward by Charles Darwin and impossible. Evolution won because
Alfred Russel Wallace in 1859 remain the it is true. Eventually, truth will out. ❚
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Newsletter
Health Check Clare
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News
REUTERS/ALASDAIR PAL
Global spread
India is catching up with the US
The number of reported coronavirus cases in India is surging, and the
true figure is likely to be even higher, reports Nilanjana Bhowmick
INDIA is on track to overtake Cases have soared since India migrant workers returning to their adults in India had been
the US as the country with the eased a strict national lockdown home states since restrictions infected by early May, equating
highest number of coronavirus in May, and some are worried that eased. “That’s when it became to 6.4 million people.
cases worldwide. With more than the spread of the virus into rural difficult to control,” says Reddy.
5.56 million recorded cases, India areas will increase case counts Despite the rising number of
set a new record with 97,859 daily and fatalities. Two-thirds of the On 14 September, India’s health cases, it is unlikely that India will
cases on 16 September. It took population lives in rural regions, minister Harsh Vardhan said that impose another lockdown. The
just 11 days for the total number which have only about a third of 1 million tests are being conducted economy contracted by 23.9 per
of cases so far to rise from 4 to the country’s hospital beds. daily. “You do need some testing, cent in the April-June quarter,
5 million, and it is likely to be but it cannot be the only public its worst decline since 1996.
just a matter of weeks before the “We will have to gear up our health strategy,” says Reddy. “We
country passes the US, which services to delay the spread of the will also have to boost heathcare On 21 September, the Taj Mahal
has some 6.85 million cases. virus to rural areas,” says K. Srinath systems and improve connections opened its doors to tourists after
Reddy, president of the Public with local communities.” six months of closure, just one
Given India’s population of Health Foundation of India. “That’s of the measures the government
about 1.38 billion, however, the going to be absolutely critical.” There are fears that testing has taken since June to revive the
number of cases is comparatively is inadequate and many cases economy, along with opening up
low. On 22 September, for instance, Even states like Kerala, which are going undetected. Research state borders, domestic flights,
the seven-day average of daily won global praise for its handling published earlier this month by malls and gyms.
confirmed cases in the US was of the virus in the initial months the Indian Council of Medical
131 per million people, compared of the pandemic, are now seeing Research looked at the prevalence These measures are sending a
with 65 per million in India. a rise in case numbers. of antibodies in the population. wrong message that “the worst is
Deaths, too, currently totalling It suggests that 0.73 per cent of over”, says Reddy. “Only when the
about 89,000 in India, are Much of the surge is ascribed to daily death rates are falling steadily
much lower than in the US, for 10 days can we feel assured
which is nearing 200,000. Daily coronavirus news round-up that the epidemic is coming down.
Before that, if we start opening up,
Online every weekday at 6pm BST we are inviting trouble.” ❚
newscientist.com/coronavirus-latest
26 September 2020 | New Scientist | 7
News Coronavirus
Testing strategies
How to get a grip on testing
The UK has grand ambitions for testing, but is struggling to get it right.
There are solutions, reports Clare Wilson
THIS month, UK Prime Minister
Boris Johnson announced an
ambition to increase the country’s
capacity for coronavirus testing
to several million tests a day.
Billed as Operation Moonshot,
the idea was received with
widespread incredulity. The
UK is currently failing to meet
demand for coronavirus testing,
with roughly half a million daily
requests outstripping supply
by up to fourfold.
Yet there are also reports of
new technologies in development
that could make testing faster
and cheaper. If the UK had the
capacity to test not just those
with symptoms of covid-19, but to ANDREW MILLIGAN/POOL/AFP VIA GETTY IMAGES
regularly test symptomless people
too, it could be a game changer in
the ability to control the disease.
From the beginning of the
pandemic, many countries have
struggled to provide enough
coronavirus tests for all those
who need them. A lack of tests is
disruptive because anyone with
symptoms that resemble those of
covid-19 has to stay at home and QR codes are used to new coronavirus. The labs are taken, but at the Lighthouse Labs
dotted around the UK and, for where they are sent. If labs fall
isolate, and must also be treated scan in samples at a new a few months, capacity seemed behind on processing, they tell
largely sufficient. testing centres not to release
as infectious within hospitals. testing centre in Glasgow more appointments.
As UK cases have begun to
Insufficient tests also make it increase again in recent weeks, Although the UK’s current
though, demand has risen. capacity for tests is around
impossible to accurately track how The drivers seem to be people 250,000 a day, some are reserved
socialising and returning to work for hospitals, so only about
the epidemic is progressing in a and school. Although children 160,000 are available to the public.
are generally less affected by the Based on estimates of phone
region, whether cases are rising coronavirus, schools are known requests and website usage, about
hotbeds for spreading coughs, three or four times as many people
or falling. “Without testing, which 10m colds and flu, which have similar are seeking tests as are able to
is our eyes and ears, we don’t symptoms to covid-19 and so can get one, according to comments
understand where this is going,” trigger test requests. made to members of parliament
says Stephen Griffin at the by Dido Harding, head of
Media reports have been full England’s test-and-trace scheme.
University of Leeds in the UK. The number of daily tests the of stories of testing centres with
empty car parks, while people Two further Lighthouse Labs
The UK faced this problem UK government reportedly trying to book online are being are opening in the next few weeks,
offered appointments hundreds which should increase testing
initially in its first wave of plans to carry out by 2021 of kilometres away. capacity to 500,000 a day by the
end of October. However, Harding
covid-19, when even hospitals The bottlenecks aren’t at the admitted to MPs that, by then, it
testing centres where swabs are
were going short of tests. To
expand capacity, five large
facilities known as Lighthouse
Labs were set up to process
polymerase chain reaction (PCR)
tests, a well-established technique. “Without testing, which
In this case, the tests are used is our eyes and ears, we
to compare samples from a nose don’t understand where
or throat swab to the genes of the the outbreak is going”
8 | New Scientist | 26 September 2020
Coronavirus Essential Guide
All you need to know about coronavirus and covid-19
Available now in the New Scientist app
still won’t be enough to meet ALEX KRAUS/BLOOMBERG VIA GETTY IMAGES equipment in research labs at be picked up by PCR. However,
rising demand. universities and hospitals. such people are less likely to be
Travellers queue at a covid-19 spraying virus into the air from
Official documents leaked testing centre at Frankfurt Peto now says that increased their lungs, so antigen tests might
earlier this month suggest that Airport, Germany capacities for other tests – for be good for quickly picking out
Operation Moonshot is aiming example, a genetic test called only people who are infectious.
for a capacity of 10 million tests Moonshot, other approaches RT-LAMP – could make mass
a day by early next year. This is may be needed. screening easier. Unlike PCR, this For now, UK mass-testing
around the same number that doesn’t need sophisticated lab schemes are sticking with genetic
would be needed to eliminate Earlier this year, Julian Peto equipment, but merely a heater tests. There are two large trials
the virus from the UK, by testing at the London School of Hygiene to warm the sample to about 65°C. combining saliva testing with the
everyone in the country once a & Tropical Medicine proposed a It gives a result in 20 to 45 minutes. fast RT-LAMP method in two cities.
week, although the government plan in medical journal the BMJ In Salford, screening of people
hasn’t stated that elimination is to use mass testing to eliminate It might be possible to speed up at indoor and outdoor venues
the goal. Instead, it has focused the coronavirus from the UK. testing further by switching from is due to begin next month. In
on testing as a means for people To achieve the necessary level looking for the virus’s genes to Southampton, children at several
to return to regular activities. of testing, he proposed hunting for molecules on its schools are starting weekly checks.
commandeering all the PCR surface, known as antigens. These
New testing methods could can be detected using artificial It was initially thought that
help. One option is a small False positives versions of the antibodies of our saliva tests wouldn’t catch as
machine called NudgeBox that can immune system that normally many positive cases as swab tests
process a sample on the spot and Any mass screening of people recognise viral antigens. This is because mucosal fluid from inside
give a result in 90 minutes, instead who don’t have symptoms can hit the same mechanism as home the nose or the back of the throat
of it having to be sent to a lab. the problem of “false positives”. pregnancy tests and, like these, should in theory contain more
coronavirus antigen tests can virus particles. So the first tests
Developed by UK biotech firm Imagine a test that is 95 per produce fast results. approved were swab ones.
DNANudge, the device is already cent accurate when it produces
being used in eight hospitals, and a positive result. It is important Antigen tests aren’t generally But it now seems that testing
the UK has ordered 5000 more. to remember that very few of as sensitive as genetic ones, but people’s saliva is effective. The US
Recent research shows it is almost the screened group really are that has both pros and cons. They Food and Drug Administration
as sensitive as standard lab testing. infected – say about one in 1000 can fail to spot some people whose granted emergency approval last
“It allows you to start therapy at any time. Of the 999 people infection is waning and so have month to two saliva tests. Such
much more quickly,” says Graham without the coronavirus, 949 relatively few virus particles in tests would be especially useful in
Cooke at Imperial College London, would correctly test negative, and their nose or mouth, but still have schools because administering the
who led the study. 50 would wrongly test positive. enough viral genetic material to invasive swab tests is particularly
hard with small children.
While this kind of machine Assuming that the one person too, then for every 51 positive
can help in hospitals, it can only out of the 1000 who really has test results, 50 would be wrong. A ready supply of tests to enable
process one sample at a time and the virus correctly tests positive Across the population, that would mass screening would allow for a
so turn around at most 16 samples lead to thousands of people radical new containment strategy,
a day. That means it can’t raise unnecessarily staying at home as testing would include people
testing capacity enough to screen and self-isolating. who are infected but have no
millions of people daily unless symptoms and so can spread the
hundreds of thousands of devices There is a solution, says Julian virus unknowingly. If enough
are manufactured. What is needed Peto at the London School of people are reached and all infected
are mass-testing devices that Hygiene & Tropical Medicine. With individuals self-isolate, it should
process multiple samples at once. fast tests that give a result in an reduce the virus’s prevalence.
hour or two, anyone who gets a
Various other kinds of PCR positive result could have another There are big questions around
tests are in use or in development test, reducing the number of false positives (see box, left) and
around the world that could help. people wrongly told to isolate. who would pay for the tests, and it
Some of these are cheaper or “The idea of false positives is a would also be vital to test visitors
easier than the standard lab tests, complete red herring,“ he says. and returning travellers, as is
or use different chemicals to happening in Germany. But done
get round any shortages of the properly, these two strategies
commonly used ones. But if together might be able to more
testing capacity is to be boosted or less eliminate the virus from a
to the levels mooted in Operation nation without a vaccine in sight. ❚
26 September 2020 | New Scientist | 9
News Coronavirus
Transmission
Virus probably didn’t take hold in
the US and Europe last December
Michael Le Page
WHEN did the coronavirus first many cases we did not see,” says had symptoms resembling covid- virus sequenced so far have all
reach Europe and the US? concluded that the pandemic
Lauren Ancel Meyers at the 19 doesn’t mean they had it. “It’s strain emerged around November.
No cases were reported outside
China until January 2020, but a University of Texas at Austin. extremely unlikely,” says Dominik On the flip side, this does mean
study published on 10 September that people in Italy may have
claims that cases in the US began But how many and how soon? Mertz at McMaster University in been infected by 18 December,
to rise by 22 December. Many as another sewage study claims,
people there and in Europe One team says it found viral RNA Canada. “I think we can be pretty and that a man in France could
suspect they had coronavirus have been infected as early as
around this time. Yet overall, the in sewage in Barcelona, Spain, as sure it was something else.” 14 December, as testing of stored
evidence suggests there were few hospital samples suggests.
cases outside China this early on. early as March 2019, but others In fact, it is very unlikely that
Based on two studies that found
Covid-19 was first recognised have dismissed this. “It is highly anyone was infected by the virus missed cases by testing stored
as a new disease in Wuhan, China, hospital samples in Wuhan and
over the course of December. On likely to be contamination,” says before November. Several teams Seattle, Meyers’s team estimates
13 January, the first case outside that there could have been 10,000
China was reported in Thailand. Kristian Andersen at the Scripps tracing its evolution by looking at cases in Wuhan by 23 January
On 21 January, the US reported its when only 400 had been detected,
first case and on 24 January, France Research Institute in California. changes in RNA of samples of the and 9000 in Seattle by 9 March,
reported three, the first in Europe. when only 245 had been reported.
The 10 September study is
This, at least, is what was known However, even if Meyers’s
at the time. But it can take up to based on the number of people “While it’s possible lots of estimates are right, it doesn’t
two weeks for covid-19 symptoms mean lots of people outside
to appear and many infected going to a group of hospitals and people in the West had Wuhan had the coronavirus as
people don’t have symptoms at all. early as December. “While it is
clinics in the Los Angeles area with covid-19 then, it is more possible, it’s much more likely
In addition, when countries they had some other respiratory
did start testing, many initially a cough, but just because people likely it was another virus” virus,” says Meyers. ❚
limited it to people who had come
from China recently. If the virus REUTERS/MANUEL SILVESTRI Venice Carnival in February
had already begun spreading, any before festivities were cut
early local cases would have been short due to coronavirus
missed. “It is certain there were
Virus origins allege that the modification of one whistle-blower from Hong Kong covid-19, she said. She claimed that
or more bat viruses was carried out whose current affiliation is the in the course of her investigation,
Still no evidence in a laboratory in Wuhan, China. non-profit Rule of Law Society and she discovered that it was caused
the coronavirus the Rule of Law Foundation, both in by an unnatural coronavirus created
was made in a lab Experts poured scorn on the New York. They were co-founded by in a Chinese government laboratory
claim. The paper “does not provide US president Donald Trump’s former in Wuhan. She said she fled Hong
A RESEARCH paper claiming any robust evidence of artificial chief strategist, Steve Bannon. Kong for the US in April after the
to prove that the coronavirus manipulation and is highly Chinese government tried to make
was cooked up in a lab has been speculative”, said Gkikas Yan did media interviews before her “disappear”.
widely dismissed by scientists. Magiorkinis at the National the preprint was posted. She told UK
and Kapodistrian University of daytime TV show Loose Women that HKU has confirmed that Yan
The paper, which was posted Athens, Greece, in a statement. last year she was a medical doctor was a postdoctoral fellow and
online last week and hasn’t been and PhD student at the University has since left the university.
peer reviewed, says that “unusual “This preprint report cannot be of Hong Kong (HKU) Medical Centre In a statement, it said that Yan
features” of the virus’s genome given any credibility in its current School of Public Health. didn’t conduct research into the
suggest “sophisticated laboratory form,” said Andrew Preston at the coronavirus at HKU, and distanced
modification rather than natural University of Bath, UK, in a statement. In December, she was assigned itself from her comments. ❚
evolution” (zenodo.org/ to a secret investigation of the Graham Lawton
record/4028830). The authors The paper was co-authored new disease that we now know as
by Li-Meng Yan, a self-styled
10 | New Scientist | 26 September 2020
Field notes
Diary from the covid-19 front line
The coronavirus has posed many challenges to doctors, the
latest being “long-tail” symptoms, says doctor Selma Stafford
THE first confirmed case of covid-19 high temperature. Their managers
in Brighton was around 1 February.
I know this because I had been to expected them back at work and
a friend’s 50th birthday party that
night. Having left early, I didn’t know they simply felt unable to go, or
anything was wrong until I received a
cryptic text from the host, something they worked for a few days then
about us meeting up “when this is
all over”. I disregarded it. were incapacitated afterwards.
I later discovered that somebody GPs had little to offer – encountering
at the party had been in contact
with this first confirmed case, so patients who continue to have
several guests had to self-isolate.
Many were doctors. physical symptoms where there
It soon became clear that letting is no clear course of treatment can
“hot” patients – those with a
potential covid-19 infection – see make doctors feel uncomfortable
their general practitioner (GP) might
take many surgeries out of action, and impotent – and were unable to
and money was made available
for new solutions. ANDREW AITCHISON/IN PICTURES VIA GETTY IMAGES see them in person anyway, so we
That is how my organisation was would assess them at the hot-hub.
tasked with setting up a “hot-hub”
for the area. The challenge We would check their breathing
was: how can you see patients
who aren’t sick enough to go rate, oxygen saturations,
to an accident and emergency
department but who might have temperature and pulse. These
covid-19, yet make it as safe as
possible for healthcare workers? were usually normal, but the patient
What if someone has covid-19 was still effectively disabled by
symptoms, for instance, and is
OK, but also has appendicitis? symptoms. We don’t have any
Our idea was to keep a patient
in their car. You could recline them medicine to offer, so all we can give
in the passenger seat and carry
out a basic examination. is reassurance that this isn’t unusual,
So we decided to set up the advice to rest and hope that it will
hot-hub in a car park, inside a
huge drive-in marquee. We paid pass as the weeks go by.
scrupulous attention to infection
control and conversations took place adept at recognising the A patient being This is a new illness, so we lack the
on the phone before and after the “covid cough” over the phone.
physical assessment, to minimise assessed at a drive-in evidence that is available for other
face-to-face contact. All the practices Some days were especially
in the area were signed up, covering difficult. I remember one clinic in Dover, UK areas. This long-tail disease seems
about 350,000 people. 60-year-old man in particular.
He had driven himself in, with similar to chronic fatigue, but can
When we started, it felt as though his wife, but when we measured
every person we spoke to had his oxygen levels, they were ambulance, and 19 minutes later also have a periodicity like a tropical
covid-19. We didn’t have access surprisingly and dangerously low.
to testing, but would advise patients I asked why he was driving, and he he was taken away. disease – some people feel better for
on the basis of the phone call and told me that he was fed up with his
physical examination. I became wife missing the turning so had I suddenly became very aware a while, and then it hits them again.
taken over at the wheel. He was
clearly unwell, so we called an of his wife in the passenger seat.
Profile She wasn’t allowed to accompany “They used to go on
Selma Stafford is a GP and
educator in Brighton, UK, him to the hospital, but had to 30-kilometre bike rides.
and clinical director of the
Sussex MSK Partnership drive home alone with the very Now they get breathless
real possibility that she wouldn’t going up the stairs”
see her husband again.
During my career, I have seen It also seems as though those with
many patients very ill and dying, but prolonged disease are more likely to
this sudden aloneness without any have initially had milder symptoms.
ability to say goodbye or accompany In fact, the majority of people I have
the loved one affected me more than seen in this camp are fit, active people
usual. After that, we made someone in their 20s and 30s. Some of them
responsible for staying with the would go on 30-kilometre bike rides
person accompanying the patient, three times a week. Now they get
to make sure we could respond breathless going up the stairs.
to their needs as much as possible. It isn’t clear whether this will
After a few weeks, the number of become a chronic illness or get
patients like this fell and we started better over months rather than
to see people who had finished weeks. We are very far from
self-isolation but were still unwell. understanding the long-term
The common feature was a residual consequences of covid-19 and
lethargy, with some people reporting now need to support and advocate
a persistent dry cough or intermittent for people who are affected. ❚
26 September 2020 | New Scientist | 11
News
Space exploration Environment
Venus fly-by may confirm Air pollution may
potential signs of life be behind millions
of deaths in China
Leah Crane
Donna Lu
ON 14 September, researchers entirely certain. When light telescopes and potentially
even new missions to Venus. UP TO 30.8 million adults in China
announced that two telescopes goes through gas in Venus’s and Taiwan are estimated to have
BepiColombo may be died prematurely as a result of air
had spotted signs of phosphine atmosphere, some of its equipped to get a phosphine pollution during a 17-year period.
fingerprint before the planned
in Venus’s clouds, and no known wavelengths are absorbed, observations. Preliminary Yang Liu at Emory University in
calculations have shown that Atlanta, Georgia, and his colleagues
non-biological processes could leaving dark lines in the light’s two of phosphine’s absorption used satellite imagery to quantify
lines are in the wavelength the amount of air pollution over
have made the gas in such large spectrum called absorption range of one of the instruments, mainland China, Hong Kong, Macao
the Mercury Radiometer and and Taiwan between 2000 and
amounts. The BepiColombo lines. Phosphine absorbs light at Thermal Infrared Spectrometer 2016. The team used imagery
(MERTIS), that was already due taken by NASA satellites to estimate
spacecraft may be able to thousands of wavelengths, but to take images of Venus as the the concentrations of PM2.5 –
spacecraft hurtles by, says team particulate matter of less than
confirm that the phosphine the telescopes that spotted the member Jörn Helbert at the 2.5 micrometres in diameter.
German Aerospace Center.
is indeed there. gas only caught it absorbing one One measurement the team
MERTIS has two cameras, used is the amount of sunlight
BepiColombo, a joint mission wavelength in Venus’s skies. but their configuration may scattered or absorbed by particles
complicate efforts to get a good in the air. Combining these readings
by the European Space Agency shot of Venus: during its voyage with PM2.5 measurements from
to Mercury, the main camera ground monitoring stations,
and the Japan Aerospace “The discovery was is folded inwards and unable as well as information about
to capture images. The second meteorological conditions and road
Exploration Agency, launched like getting a partial MERTIS camera is a calibration networks, the researchers trained
tool designed to take images a machine-learning algorithm to
in 2018. Before it arrives at fingerprint and we want of space to capture ambient predict PM2.5 exposure.
light and remove its effects
Mercury in 2025, it will pass lots of fingerprints” on the main camera’s data. To estimate the total mortality
As BepiColombo passes Venus, linked to air pollution, the team then
near Venus twice, using the this poorer quality calibration used historical data from a study
camera might be able to of 116,821 adults in 15 Chinese
planet’s gravitational pull to “The discovery was only search for phosphine, says provinces, which quantified the
David Rothery at the Open link between long-term PM2.5
adjust its trajectory. one line – that would be like University in the UK. exposure and non-accidental
death. There was a roughly linear
The first pass should occur getting a partial fingerprint, and Luckily, there will be another relationship between PM2.5
chance. “We have a second fly-by exposure and mortality, up to a
on 15 October, and the team we want lots of fingerprints,” coming up in August 2021 where certain point (PNAS, doi.org/d9n5).
we are even closer to Venus,”
had already planned to test the says Sara Seager at the says Helbert. “The people who live in
the most polluted regions get
craft’s instruments by observing Massachusetts Institute of Without the main MERTIS disproportionally harmed,” says Liu.
camera and with no time to alter
Venus. Now, the researchers are Technology, who is part of the the October fly-by plans, it isn’t The highest per-capita deaths
certain whether BepiColombo due to air pollution were found
working out how to use them team behind the detection. The can confirm there is phosphine in the north-eastern Chinese
in Venus’s atmosphere next provinces of Hebei, Henan,
to check the phosphine finding. researchers are now working month. If it does, we will then Shandong and Tianjin.
be left to figure out whether
This is important because on plans to examine the light the gas is truly is a sign of life. ❚ To date, most air pollution
monitoring has been done from
the phosphine discovery isn’t further with Earth-based stations on the ground. In China,
these are concentrated in urban
ESA/ATG MEDIALAB The BepiColombo areas, which doesn’t account for
spacecraft depicted some 600 million people in rural
passing Venus areas. In addition, measurements
before 2013 are scarce. ❚
12 | New Scientist | 26 September 2020
Technology
Most fertility apps are unreliable,
but free ones work best
Jessica Hamzelou
FERTILITY-TRACKING apps can CHEE GIN TAN/GETTY IMAGES/ISTOCKPHOTO Still, no prediction will be
provide misleading information perfect, and only 57 per cent of
and shouldn’t be relied on to says. Harper’s recent research, Many fertility-tracking apps provided any disclaimer to
help people conceive or as a based on the data from another apps give imprecise this effect. Just five advised against
contraceptive tool, according to fertility app, suggests ovulation ovulation predictions using the app to avoid getting
an analysis of mobile phone apps occurs on day 17, on average. pregnant. “They shouldn’t be
available in the UK and Canada. The more robust apps took relied on for contraception,”
“In our study, women ovulated into account other markers says Rhonda Zwingerman at the
There are hundreds of apps anywhere between day 10 and day of fertility based on user input, University of Toronto in Canada,
that offer to track periods in order 26,” says Harper. Apps that rely such as body temperature, which who wasn’t involved in the study.
to help people either achieve or only on dates provide inaccurate rises during ovulation, and
avoid pregnancy. To find out how information, and could, say, information about the changing That doesn’t mean apps can’t
reliable they are, Joyce Harper at result in some users missing their state of cervical mucus. Harper be useful. Apps that track period
University College London and her fertile window, she warns. says she was surprised to find that, dates can help those who want to
colleagues considered all 200 of on the whole, the free apps used be reminded when their period is
the fertility-tracking apps offered 22% more of these biomarkers than due, or could indicate if periods
on Apple’s mobile iOS app store. paid-for apps did (Reproductive seem unusually far apart, which
Proportion of period-predicting BioMedicine Online, doi.org/d9bj). might signal ovulation problems.
The team removed apps from apps with “serious inaccuracies”
the list if they were faulty, hadn’t Yet they aren’t always accurate.
been updated within three years In other research, Harper has
or didn’t offer to predict a user’s entered the same dates into
“fertile window”. This left 90 apps. 10 apps, and they gave varying
Just over half of those predicted dates of the next period. And
this window based on when Zwingerman has shown that
a user has their period. about 22 per cent of such apps
had “serious inaccuracies” in
This “calendar method” is based information they provided.
on the idea that ovulation typically “Almost all of those claimed to
happens on day 14 of the menstrual be able to predict the gender of
cycle and fertility is highest in the your child based on when you
days before this. But this method had intercourse in the cycle,”
is flawed, says Harper. “Not every says Zwingerman. “Just to be
woman has a 28-day cycle, we clear, that’s not how it works.” ❚
don’t all ovulate on day 14,” she
Health
Nut allergies spike children tended to go up at certain SHUTTERSTOCK/AS FOOD STUDIO Halloween treats “Halloween and Easter
on Easter and times of the year. can trigger involve social gatherings with
Halloween dangerous other children in the presence of
Ben-Shoshan and his colleagues reactions in a lot of candy. These holidays may
EACH year, severe allergic reactions used records of emergency room children with include interactions with other
to nuts spike in children around visits to analyse the incidences of nut allergies adults who may not be aware
Easter and Halloween, according to nut-induced anaphylaxis – a severe of the child’s food allergies,” says
an analysis of data from emergency allergic reaction – in children across child had eaten tree nuts or peanuts Tina Sindher at Stanford University
rooms across Canada. Quebec, Ontario, British Columbia (Canadian Medical Association in California. She adds that “a lot
and Newfoundland and Labrador. Journal, doi.org/d9mg). The team of fun-size candy may not be
“I’m not so surprised,” says didn’t find a significant increase labelled appropriately”.
Moshe Ben-Shoshan at McGill In 1390 cases between 2011 in nut-induced allergic reactions
University in Montreal, who led and 2020, they saw that rates of during other holidays, such as Children with food allergies
the study. As a paediatric allergist peanut-triggered anaphylaxis were Christmas, Diwali, Chinese New should always carry an epinephrine
who regularly works in the 85 per cent higher than average Year and Eid al-Adha. autoinjector, such as an EpiPen, and
emergency room, he noticed that on Halloween and 60 per cent parents should make other adults
severe allergic reactions among higher during Easter. They saw aware of allergies, says Sindher. ❚
a similar trend for anaphylaxis in Layal Liverpool
cases where it wasn’t clear if the
26 September 2020 | New Scientist | 13
News
Science in the media
US science coverage is biased against
people with names not of British origin
Donna Lu
NEWS coverage in the US of those whose names were of findings,” says Marcus Ryder at but that this alone didn’t account
scientific work is biased against European origin. The greatest Birmingham City University, UK. for the disparity. Authors with
researchers whose names aren’t disparity was seen in general “There is no doubt that the media names not of British origin based
of British origin. news outlets, such as certain confers legitimacy and authority outside the US were even less
newspapers, where researchers to deciding who the voices we likely to be mentioned, potentially
Hao Peng at the University with names of African and should be listening to are.” because of perceived difficulties
of Michigan and his colleagues Chinese origin were 10 per in interviewing them due to
analysed more than 230,000 cent less likely to be mentioned “People with names not time-zone or language-fluency
news stories from 288 US outlets, (arxiv.org/abs/2009.01896). of British origin were issues, according to the study.
which reported on around significantly less likely to
100,000 different research To perform the analysis, the be mentioned or quoted” “[Media coverage] not only
papers across all scientific fields. team used Altmetric, a database affects public perception about
that aggregates media and online When examining possible who is a scientist, it also affects
The team looked at whether coverage of scientific papers. factors contributing to the bias, new scientists when they enter the
the first authors of papers were the team found that geographical academic world – who they choose
mentioned in news coverage. “Most people who work location was a major component, to be advised by, who they choose
Very often, these are junior in journalism have personal to collaborate with,” says Peng.
researchers who have contributed anecdotes that support these
most significantly to the work. The researchers noted a small,
Peng and his colleagues found MB PHOTO/ALAMY gradual increase in the number
that first authors who had names of times scientists with names of
that weren’t of British origin Chinese or Indian origin, as well
were significantly less likely to be as those in languages derived
mentioned or quoted than first from Latin, were mentioned. They
authors with names that were. predict that scientists in these
groups may reach parity with
On average, the probability of colleagues who have names of
featuring in a news article was up British origin in five to 12 years,
to 6.4 per cent less for researchers but that the gap will persist for
with names of non-British origin. other minority ethnicity authors.
The greatest decreases were for
people with names of Asian or The team also found a gender
African origin compared with imbalance across the news
coverage, but it reflected existing
A news stand disparities between the numbers
in the New York of male and female researchers
subway in Manhattan in those scientific fields. ❚
Human evolution
People in Cape Verde 564 Cape Verdeans. They found The Cape Verde archipelago was 0.08, one of the highest inferred
have evolved better that around half the people on uninhabited before Portuguese in humans,” the researchers write
malaria resistance the outer islands have a variant voyagers arrived in the 15th (bioRxiv, doi.org/d9mh).
of a gene called DARC that protects century, bringing slaves from Africa
WE ARE still evolving, and one of the against malaria. with them. This explains why the By comparison, selection
best examples of recent evolution in DARC gene variant is present in the coefficients are estimated to be
people has been found on the Cape However, on the more densely Cape Verdean population today, between 0.02 and 0.14 for the
Verde islands in the Atlantic. There, populated main island of Santiago, because it is also seen among many lactase tolerance variants that
a gene variant that confers a form where there have been many people of West African origin. allow adults to digest milk, says
of malaria resistance has become malaria outbreaks over the Sharon Grossman at the Broad
more common over just 550 years. centuries, about 80 per cent The strength of selection for a Institute in Massachusetts, who
of people have the variant. particular gene variant – how fast wasn’t involved in the research.
Amy Goldberg at Duke University On Santiago, there has been it spreads per generation – can be For the sickle cell variants that
in North Carolina and her colleagues strong selection for the malaria- calculated, and is called the selection also convey malaria resistance,
analysed data on gene variants in protecting variant: in other words, coefficient. “We estimate the they are between 0.05 and 0.18. ❚
the population has evolved. selection coefficient is approximately Michael Le Page
14 | New Scientist | 26 September 2020
Newsletter
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newscientist.com/fix
News Conservation
Space exploration World falls short on all
its biodiversity goals
Astronauts are
mainly men and Adam Vaughan
are getting older
A GLOBAL push to protect destruction, such as economic shows “global coordination
Joshua Rapp Learn biodiversity has failed to fully growth that can lead to forests can make a real difference in
meet any of the targets set by being converted to farmland. protecting biodiversity”.
THE average age of people sent to governments a decade ago,
space has been on the rise since Yuri leading conservationists to Richard Gregory at the UK’s The report makes clear the
Gagarin first blasted off in 1961, condemn nature protection Royal Society for the Protection situation would have been even
and the vast majority of the 566 efforts as a “massive failure”. of Birds says the number of worse without conservation
people who have left Earth are missed targets means the report efforts. Up to four times as
male, according to a new analysis. A United Nations report makes for grim reading. “This many birds and mammals
reveals only six of the “Aichi represents a massive, if not would have gone extinct
Svetlana Komarova at McGill targets” for 2020 have been catastrophic, failure at all levels,” without action in the past
University in Montreal, Canada, partially achieved. The other he says. Significantly, there are decade, the authors estimate.
wanted to understand more about 14, such as eliminating subsidies positive signs when it comes to
how space flight affects bones, that are driving biodiversity loss policies supporting biodiversity Tim Hirsch at the Global
but found that data on spacefarers or halving the rate at which protection, but the drivers of Biodiversity Information
wasn’t in any central scientific natural habitats are being lost, Facility in Copenhagen,
database. Such lists have only been have been completely missed. 20 Denmark, one of the report’s
put together by space enthusiast authors, admits the scorecard
websites. “Only fans care,” she says. The goals were agreed by targets were agreed in 2010 to is a “big disappointment”, but
almost 200 governments at tackle major threats to wildlife says that doesn’t detract from
Her team began to gather a 2010 meeting of the UN progress. Bright spots include
information from space agencies Convention on Biological loss, such as land use change work on stopping invasive
around the world and decided Diversity (CBD) in Nagoya, and the current state of species, the growth in protected
to analyse the demographics of Japan. They aimed to stem biodiversity itself, mostly show areas of land and ocean and
spacefarers. It found that the the destruction of species and worsening trends, he adds. the doubling of financing for
average age of crew has increased habitats, but the CBD analysis biodiversity projects.
from 34 in the 1960s to 45 in the shows that countries have Felicia Keesing at Bard College
2010s (Life Sciences in Space failed to address the structural in New York says that despite David Cooper at the CBD
Research, doi.org/d9fd). problems driving nature’s the shortcomings, the analysis rejects the idea efforts have
been a failure, but says there is
Komarova said this may reflect HOTLI SIMANJUNTAK/EPA-EFE/SHUTTERSTOCK only so much conservationists
the fact that in the early days, we can do. “We can do things that
sent younger, stronger types as are specific for biodiversity, like
we were mostly interested in how protected areas, but they’re
space might affect humans. Once being overwhelmed by the
we understood it was relatively more society-wide, economy-
safe, the cost of launches meant wide pressures that have not
an increased desire for experience changed enough.”
and knowledge. “The demands
of space travel now require very The analysis follows a warning
highly educated people,” she says. that a million species are facing
“The requirements for astronauts extinction and comes ahead of
are driven by what they do in a CBD summit in China in May
the [space] station, and the 2021, originally due this October.
requirements are going up and up.” The aim is for governments
to hash out new biodiversity
Only 64 of all space travellers targets that conservationists
have been female — about 11 per hope will be more successful
cent — though the proportion has than those agreed in Japan.
increased since the 1980s. The “If the covid-19 pandemic
average age of women in space doesn’t motivate us to make the
hasn’t increased as much as that changes we need to make, I don’t
of men, which Komarova speculates know what will,” says Keesing. ❚
could be due to the impact of the
menopause on older women. This Forest cleared for oil
can lead to bone loss, and since palm plantations in
space travel also weakens bones, Aceh, Indonesia
older women may present a higher
risk than sending younger women
or older men, she says. ❚
16 | New Scientist | 26 September 2020
Weather NOAA
Storming the Atlantic
A rare cluster of cyclones was captured by a satellite
Michael Le Page
FIVE named tropical storms
were present in the Atlantic on
14 September – only the second
time this has happened since
records began. The image here
shows all five, plus tropical storm
Karina in the Pacific. Most remained
at sea, but Sally, which intensified
into a category 2 hurricane, caused
damage across the US Gulf Coast.
The 2020 hurricane season has
been so active that all 21 names on
the list for this year have been used.
After storm Wilfred, which formed
after this picture was taken, the US
National Hurricane Center will use
the names of Greek letters.
The number of tropical storms
varies each year. High wind
shear - the difference between wind
speeds at the surface and higher
up - can rip potential storms apart.
Global warming may not increase
the number of hurricanes, but there
is evidence that it makes them
stronger and more damaging. ❚
Physics
Clearest signs yet that water is two liquids
SUPERCOOLING liquid water packed more closely together using infrared spectroscopy, can’t simply be explained by
to record low temperatures and others spaced further apart. a method that takes advantage water crystallising into ice.
has revealed new evidence of the way infrared light is “We noticed that there was
that it can exist as two different But researchers have struggled transmitted through molecules. something funny happening
liquids simultaneously. to study these two different Repeated experiments revealed early on before it was really
liquids, because supercooled fluctuations in the density of crystallising,” says Kimmel
Supercooled water – liquid water usually freezes the supercooled liquid consistent (Science, doi.org/d9d7).
water chilled below its freezing nanoseconds after it is formed. with the two-liquid hypothesis.
point without being allowed to “Water has many strange
freeze – has been baffling chemists By firing lasers at an extremely The researchers could identify properties,” says Anders Nilsson
for decades. Previous studies thin sheet of ice, Greg Kimmel a temperature range within which at Stockholm University in
found that the extent to which and Bruce Kay at the Pacific supercooled water transitions Sweden. But this is the clearest
water molecules pack together, Northwest National Laboratory between its two liquid forms: experimental evidence of
known as their density, starts to in Washington were able to between about -93°C and -33°C. two-liquid structures, he says.
fluctuate as water is cooled to briefly generate and analyse
extremely low temperatures. supercooled liquid water at By increasing or decreasing Understanding water’s unique
much lower temperatures than the temperature within the chemistry could help us predict
Since then, evidence has been had been possible previously. critical range, the team also how it might behave under
mounting that these fluctuations discovered that you can tip the unusual conditions, such as in
may indicate the presence During the fraction of a second ratio of the two liquids one way outer space, says Paola Gallo at
of two different liquids in one, in which the water was in its or the other, suggesting that Roma Tre University in Italy. ❚
with some water molecules supercooled state, the team the two-liquid phenomenon Layal Liverpool
took a snapshot of its structure
26 September 2020 | New Scientist | 17
News Analysis Health technology
Marine biology New Apple Watch monitors blood oxygen – is that useful?
The tech firm says its watch isn’t meant for medical purposes,
Triggerfish jumps so what is its oxygen monitoring good for, asks Clare Wilson
out of the water
to catch crabs Lights on the back of
the latest Apple Watch
Jake Buehler measure blood oxygen
A TITAN triggerfish, which can grow APPLE use the electrocardiogram (ECG)
to a length of 75 centimetres, has function that was introduced with
been seen beaching itself to feed APPLE’S recently released Series 6 New Scientist’s requests for further the Series 4 watch, launched in
on crabs along the shoreline. smart watch has a new feature: it details. A spokesperson couldn’t 2018. This can detect if electrical
can measure blood oxygen levels. share any published research activity in the heart is disturbed.
In 2018, Matthew Tietbohl at The tech must have been years showing how oxygen monitoring The criticism of that feature was
King Abdullah University of Science in the making, but the timing of would help a typical healthy person. that it might detect harmless
and Technology in Saudi Arabia its release worked well given that small changes that have no effect
was surveying a beach on the Red we are in the middle of a global But tools to track personal on the body, but if someone finds
Sea’s Mar Mar Island for sea turtle respiratory pandemic. health may come to the fore as the they have low oxygen levels as
tracks when he and his team heard coronavirus pandemic continues. well as heart rhythm problems,
loud splashing at the water’s edge. The amount of oxygen in Home oxygen monitoring is in that becomes more useful.
the blood is important medical no way a test for covid-19, yet it
“We turned to see this triggerfish information. In hospitals, it is could help those who have already The night-time monitoring
launching itself into the shallows usually measured with a device been diagnosed and are not sick could help to alert people
and stranding itself,” says Tietbohl. called a pulse oximeter, which enough to be in hospital but want about sleep apnoea, when they
shines a light through the finger reassurance about their condition. have problems breathing at night,
It soon became clear that the or earlobe. Blood carrying more Some UK clinics are piloting usually due to being overweight.
fish was attempting to feed on oxygen absorbs light differently. This can cause people to wake
ghost crabs that were grazing on “If we knew the device up when their blood oxygen
algae-covered rocks at the water’s It is already possible to buy a was absolutely robust gets too low, although they
edge. The triggerfish would stalk fingertip pulse oximeter for use at and accurate, then there may not be aware of how much
the crabs from the water, turn home for about £20. Now Apple would be a place for it” their sleep is being disturbed.
on its side and lunge out of the says it has replicated this function
shallows like a crocodile. At one in its high-tech watch, which “virtual wards”, where people who Because most pulse oximeters
point, the fish gripped a crab and shines a light onto the back of might otherwise be admitted to are applied to the finger or earlobe,
pulled it back into the water (Journal the wrist and measures the light hospital stay home and do phone it is unclear how well this new
of Fish Biology, doi.org/d9d6). reflected back with embedded check-ups, and pulse oximetry method will compare. Even highly
sensors. The user must keep is a key part of their monitoring. accurate devices sometimes give
75cm their arm still for 15 seconds. erroneously low readings when
The device also takes periodic Other conditions could benefit people’s hands are cold, says
The maximum body length readings when the person from home oxygen monitoring, Andy Whittamore, clinical lead for
of an adult titan triggerfish happens to be still, day and night. such as chronic obstructive Asthma UK and the British Lung
pulmonary disease, a long-term Foundation. “There are a few gaps
The determined diner was In a press statement, Apple was lung condition that can cause a there in terms of how we interpret
about 35 centimetres long, but titan vague about the purpose, saying need for supplementary oxygen. this device,” says Whittamore.
triggerfish (Balistoides viridescens) it offers “insight into overall
can be more than twice that length. wellness”, and didn’t answer It could also help when people Even Apple says in the small
print on its press statement that
Tietbohl says the feeding the oxygen measurements are
strategy may help avoid “not intended for medical use,
competition with other predatory including self-diagnosis or
fish. Supplementing a diet with consultation with a doctor, and
terrestrial prey “would open up a are only designed for general
whole new food source that other fitness and wellness purposes”.
fishes just can’t [exploit]”, he says. Until the firm releases data on the
accuracy of the watch’s readings,
Tietbohl wants to know if the it is hard to know how useful it
hunting style is used by related will be. “If we knew the device
species or is widespread among was absolutely robust and
titan triggerfish. The team did accurate, then there would be
see other triggerfish “patrolling” a place for it,” says Whittamore. ❚
the island’s shallows.
Because water and air refract
light differently, Tietbohl thinks
it is intriguing that triggerfish are
able to spot and track terrestrial
prey from below the water. ❚
18 | New Scientist | 26 September 2020
News In brief
Animals
The knobs on a giraffe’s
head can prove deadly
SHUTTERSTOCK/MITCHELL KROG DURING a rainstorm on 29 February, dead with a wound on top of her
PLAINPICTURE/GLASSHOUSE/DERRICK GOMEZ two giraffes were killed by lightning head. It appeared as if one of her
in Rockwood, a conservation area ossicones – the horn-like knobs
in South Africa. While it may seem on a giraffe’s head – may have
unsurprising that the world’s tallest acted as a lightning rod in the storm.
animal faces this risk, scientists had “It looked like the ossicone broke
never described this occurrence in off,” says Scheijen.
any detail until now.
The body of a younger female lay
“It came as a bit of a surprise 7 metres away. She was probably
to me because the whole day was killed by a side flash from the
quite quiet in weather, and suddenly strike – in which the lightning
there was this big storm,” says Ciska jumped from the matriarch – or
Scheijen, a conservation scientist at by ground current, as she was
Rockwood who had been following standing close to the other giraffe
a group of eight giraffes in the area. (African Journal of Ecology,
DOI: 10.1111/aje.12785).
Scheijen says she immediately
suspected something was wrong “It’s possible that this happens
with the herd after the storm, as she more often to giraffes than other
could only see six of the animals. species because of their height.
But I think more research is needed
Rockwood ranger Frans Moleko to see if this has an effect on the
Kaweng went out to investigate and natural selection of giraffes,” says
found the oldest and tallest giraffe Scheijen. Joshua Rapp Learn
of the herd, the matriarch, lying
Neurology Pollution
Sleep’s role seems to which can then be tested against The heavy cost of microfibres that has been emitted
change in toddlers published findings. clothes washing to the ocean is equivalent to about
7 billion fleece jackets just being
WHY do we sleep? The answer may The group found that most MILLIONS of tonnes of tiny thrown into the ocean,” says Jenna
depend on your age, according to of the brain processes associated microplastics have been shed Gavigan at the University of
research that suggests the main with learning occur during REM from our clothing into the California, Santa Barbara. Similar
role of sleep shifts at the age sleep, and that this appears to be environment over the past amounts of shed microfibres have
of around two-and-a-half. the most important function of seven decades or so, according ended up on land, mostly cropland.
sleep generally in young infants, to an analysis of the impact of
Newborn babies sleep a lot, and who get much more REM sleep clothes washing. Between 1950 Microfibres – strand-like
this gradually reduces as they get than adults (Science Advances, and 2016, an estimated 5.6 million particles of microplastics – come
older. To find out why sleep alters doi.org/ghb7x7). tonnes of such particles have been from washed clothes, particularly
as the brain develops, Van Savage emitted – half in the past decade synthetic fabrics. Researchers are
at the University of California, But there seems to be an abrupt (PLoS One, doi.org/d9d5). only beginning to learn how these
Los Angeles, and his colleagues shift in toddlers. “Before two-and- particles might effect ecosystems,
collected published data on brain a-half, sleep is mainly about… “By mass, the amount of but they can be ingested by small
activity and size and sleep duration rewiring the brain to learn and marine organisms, such as
across different age groups. grow,” says Savage. But after this plankton, and work their way
age, the main function of sleep through the food chain.
They used this information to appears to be the repair of any
build a model of how these aspects damage to the brain. “I was Microplastics often act as
might be expected to change as we surprised that it was such a sharp “sponges” for toxins, says Gavigan,
grow. This allowed them to swap transition point,” says Savage, and are able to transport a variety
in different figures to test various who likens the sudden change of chemicals into an animal’s
ideas. For example, if the brain to water freezing into ice. digestive tract, some of which
is learning during rapid eye are likely to be harmful. The
movement (REM) sleep, this The findings need to be particles are also thought to cause
would lead to a prediction that confirmed by studying how physical damage once ingested
the duration of REM sleep is linked children’s brains change over by animals. We don’t yet know
to aspects of brain development, time, says Rebecca Spencer at how detrimental these tiny
the University of Massachusetts fibres might be to humans. JH
Amherst. Jessica Hamzelou
26 September 2020 | New Scientist | 19
News In brief New Scientist Daily
Really brief Get the latest scientific discoveries in your inbox
newscientist.com/sign-up
Bees trained to
prefer sunflowers Health
BORIS KOZLOV/ALAMY Honeybees that have been Your shoes may raise way that the soles of most shoes of the foot were during walking.
coached to prefer feeding the risk of foot pain curve upwards under the toes, The results show that footwear
from sunflowers have a feature called a toe spring.
boosted seed production SHOES that push up the toes with a toe spring means the
on Argentinian farms by make walking easier, a small study “It is such an obvious feature of muscles have to do a little less
60 per cent. Being given shows. The downside is that this nearly every shoe,” says Sichting. work per step to stabilise the foot,
sugar with a sunflower-like may weaken the foot, increasing Despite this, no one had studied its says Sichting, with higher toe
scent encourages the bees the risk of a common and painful effect on the foot before, he says. spring angles boosting the effect
to seek out and feed from condition called plantar fasciitis. (Scientific Reports, doi.org/d9fb).
similar flowers in their So Sichting, Lieberman and
environment (Current When Freddy Sichting at their colleagues got 13 volunteers This could weaken the muscles
Biology, doi.org/d9d2). the Chemnitz University of aged between 19 and 33 to walk and place stress on other tissues
Technology in Germany went on a treadmill while barefoot or such as the plantar fascia, a layer of
Emergency sirens running with Daniel Lieberman wearing sandals with a toe spring connective tissue running under
and wolf howls of Harvard University – whose angle of 10, 20, 30 or 40 degrees. the foot. Putting the foot under a
work helped popularise barefoot lot more stress than normal raises
A sound analysis suggests running – the pair discussed the Using sandals rather than shoes the risk of damaging this tissue
the wail of an emergency allowed them to record the foot’s and developing plantar fasciitis,
siren is similar to a wolf 3D motion. From this, they could says Sichting. Michael Le Page
howl. This may be no work out how active the muscles
coincidence, say biologists:
wolves are dangerous, and Botany Machine learning
so early humans may have
evolved to recognise howls AI can tell what
as an alert signal. Sirens surfaces feel like
may exploit this adaptation
(Acta Biotheoretica, JURGEN FREUND/NATUREPL.COM AN AI linked to a camera can tell
doi.org/d9d3). the physical properties of surfaces
Stinging tree injects animals without touching them.
100-million-year- with spider-venom-like toxin
old fossilised sperm Matthew Purri and Kristin
AUSTRALIA may be notorious Both these species, commonly Dana at Rutgers University
A 0.5-millimetre-long for its venomous animals, such as found in rainforests in eastern in New Jersey have trained an
female shrimp mated just snakes and jellyfish, but the country Australia, are covered with felt-like algorithm that can determine
before becoming trapped in is also home to dangerous plants. hairs that can penetrate human skin the tactile traits of an object when
tree resin 100 million years Some produce toxins that look and deliver the toxin, which can presented solely with a photograph
ago – and its body still very similar at the molecular level hospitalise people. “The pain can or series of images of it.
contains about 50 sperm to spider and scorpion venom. last for such a long time,” says Vetter.
within its reproductive They took photographs of more
tract. They are the oldest Irina Vetter at the University The team identified the trees’ than 400 materials, including
animal sperm cells ever of Queensland in Brisbane and her main pain-causing toxins as a group cloth, plastic, leather and wood
found (Proceedings of colleagues examined the toxins of peptides consisting of 36 amino surfaces. The pair took 100 images
the Royal Society B, produced by the giant Australian acids. The toxins have a knot-like of each surface using a device with
doi.org/d9d4). stinging tree (Dendrocnide excelsa, structure that resembles the venoms an arm that can be moved to take
pictured above), which can reach found in spiders and scorpions photos at exact camera angles.
35 metres in height, and the (Science Advances, doi.org/d9fc).
shrub-sized gympie gympie These images were linked to
(Dendrocnide moroides), the Stinging trees may have an existing data set about the
most toxic of the six Dendrocnide developed these animal-like toxins materials. For each material,
species in Australia. as a defence mechanism against 15 physical properties were logged
mammals. Donna Lu in categories including friction,
adhesion and texture.
Using all this, they trained
a deep-learning algorithm and
tested it on surfaces it hadn’t seen
before. Given a single image taken
from directly above an object, the
algorithm could reliably estimate
14 of its 15 surface properties
(arxiv.org/abs/2004.14487).
The researchers believe the
algorithm could be used in
robots and in cars to improve
road safety by estimating the
surface properties of roads. DL
20 | New Scientist | 26 September 2020
Views Aperture Letters Culture Culture columnist
Beautiful but deadly, Views on the “fuzzi- Incredible stories Simon Ings on Hope
The columnist California’s wildfires verse”, the pandemic of the human brain’s Frozen, a journey into
Annalee Newitz takes caught on camera p24 and much more p26 ability to adapt p28 cryogenics p30
the long view amid a
year of disasters p22
Comment
Let’s get back to Venus
Phosphine in Venus’s atmosphere could be a sign that life is there.
The only way to find out for sure is to go have a look, writes Peter Gao
MICHELLE D’URBANO IF MARS were the popular kid Venus since the late 1980s. What’s agencies focusing on landing guarantee that these efforts will
in school, Venus would be more, no US mission has plumbed more craft and even people on its reveal the true nature of this
the nerd sitting in the corner, the depths of its atmosphere and surface, the phosphine discovery substance on Venus.
largely ignored. Despite its image, probed its surface since the has people looking at Venus in a
Venus is the brightest object in the Pioneer Venus missions that new light. As NASA administrator A new mission to directly
sky after the sun and the moon, departed Earth in the 1970s. Jim Bridenstine tweeted: “It’s sample the atmosphere and
its orbit taking it closer to Earth time to prioritize Venus.” surface would be a watershed
than any other planet in the solar Other countries have had more moment in planetary science. It
system. It has nearly the same recent efforts: the European Space In the months and years to need not only look for signs of life,
mass and size as Earth, but being Agency’s Venus Express orbited come, computer simulations but also answer some of our many
closer to our star, it gets nearly the planet throughout the late will be used to further study questions about Venus, such as
twice as much heat from the sun. 2000s and early 2010s, while the possible chemistries of the why it became so different to Earth
Japan’s Akatsuki orbiter is atmosphere on Venus. More and whether it was once habitable.
However, instead of having exploring Venus right now. But observations will be made (and
a climate that is just a warmer these missions were ill-equipped the old ones reanalysed) and Some options to do this
version of Earth’s, Venus’s surface for detecting phosphine or life. laboratory experiments will be already exist. There are two
and atmosphere are hellish: conducted to try to identify other NASA missions currently vying
clouds of sulphuric acid blanket While Mars has been the focus ways the phosphine there could for approval, India aims to send
the planet, while at ground level of interplanetary exploration be produced. However, there is no an orbiter to Venus in 2023 and
it is hot enough to melt lead. efforts of late, with some space private company RocketLab also
Despite this, there is now a sign has plans to visit in that year,
that Venus may harbour life. hopefully with a probe passing
through the planet’s atmosphere.
Jane Greaves at Cardiff
University, UK, and her colleagues By sampling the chemistry
recently detected phosphine in in the Venusian air, we would be
Venus’s atmosphere, with one able to take direct measurements
potential explanation that it is of phosphine and see how it varies
the by-product of biology. That is with height, capture any other
because the only way this gas is chemicals that contribute to its
made on Earth is in laboratories or formation and potentially detect
by microbes. Though this doesn’t any life that may be there.
mean it was produced by life
on Venus, attempts to find non- The discovery of phosphine
biological explanations for its in Venus’s atmosphere is a great
presence have so far fallen short. accomplishment. The scientific
endeavour it has set in motion is
Our best hope for confirming or as if a sleeping giant has awakened
rejecting the possibility of life on and it may be just what we need to
Venus is to go and have a proper finally refocus on this neglected
look. During the cold war, the USSR world. The quiet kid in the corner
sent more than a dozen missions may yet get the last laugh. ❚
to Venus, including several landers
and a pair of balloons, but these Peter Gao is a Sagan
ended well before the dawn of the Postdoctoral Fellow at the
1990s. Likewise, NASA hasn’t University of California,
launched a mission dedicated to Santa Cruz
26 September 2020 | New Scientist | 21
Views Columnist
This changes everything
California’s burning With wildfires raging, the outlook looks
bleak from San Francisco. Thinking about the future in terms
of “hope horizons” can help, writes Annalee Newitz
O UTSIDE my window, My definition is deliberately been “alright”, if by that we mean
the skies are brown open-ended. It raises questions having some meaningful degree
and the sun is a deep like “What is ‘alright’?” and “What of autonomy and control over
their lives. Maybe they grew
reddish-orange. Unfortunately, do you mean by ‘everything’?” up in war-torn regions or in
devastatingly poor families. Or
that isn’t because I’ve moved That’s the point. Teasing out perhaps their futures have been
blighted by systemic prejudice,
off-world to a beautiful alien the answers reminds us of two xenophobia or genocide. We can
imagine a million reasons – some
planet orbiting a red dwarf star. important facts. The first is that of them political, some of them
personal – why one person’s
This is simply what “outside” nothing is ever “alright” for idea of “alright” might be the
opposite of another’s.
looks like in San Francisco when everyone. The second is that
As we face a terrifying future,
Annalee Newitz is a science vast swathes of the western US “everything” is actually a bunch we have to keep in mind that
journalist and author. Their our problems won’t be solved
latest novel is The Future of are on fire. Even the light itself of unrelated stuff, some of which all at once. We might stabilise
Another Timeline and they our imperilled democracies
are the co-host of the is alarming. Its Mordor-esque matters to you and some of which just in time to watch places like
Hugo-nominated podcast California burn so catastrophically
Our Opinions Are Correct. gloom makes everything seem matters to me, and the sum of that it is no longer possible for
You can follow them people to live in them anymore.
@annaleen and their website like it is the wrong colour. (For which cannot be fixed by either
is techsploitation.com Or we might finally have
a striking image of California’s of us, ever. enough tests and protective
Annalee’s week equipment to cope with the
Bidwell Bar Bridge against the It is a useful way to put our next coronavirus pandemic,
What I’m reading but only because we are vastly
The Hidden Persuaders, backdrop of the state’s wildfires, problems into perspective and it underpaying the workers who
a 1950s book by Vance make all of that stuff. What good
Packard about subliminal see page 24.) is also a good method for figuring is a face mask if you cannot
advertising that feels actually afford to buy one?
strangely relevant in It has been a bad year for
our social media world. The best strategy is to pick
California. After years of drought, “I’m contemplating the problems whose hope
What I’m watching horizons are within reach,
Lovecraft Country, a we started getting record high something I call a hope while also keeping the rudder
series about how sci-fi temperatures that were coupled horizon, or how many steering us towards those distant
nerds fight monsters with fierce winds. years it might take millennia when humans might be
and white supremacy. before everything able to bring our planet’s runaway
Back in 2018, our doddering carbon cycle back under control.
What I’m working on old power lines, mismanaged Most importantly, we need to
A podcast about how remember who could be harmed
we’ll survive climate and neglected, sparked a deadly becomes alright again” by such efforts as well as who
change (or not). they could benefit.
fire that was supposed to be a
This column appears Every single catastrophe I am
monthly. Up next week: once-in-a-lifetime Armageddon. out what to tackle next. For watching unfold in front of my
James Wong eyes was caused by a combination
It turns out that was merely a example, looking into the of natural disaster and political
failure. That’s why we are going
beta test. hellish light of my smoky city, to need more than science and
technology to fix this. We are
This year, the southern my hope horizon is set at roughly going to need better political
systems, too. ❚
California desert reached 54.4°C. 10,000 years. That’s because
If verified, this is the hottest I’m thinking about climate
temperature ever reliably recorded change and how long it might
on Earth. Then a rare lightning take before we see an end to
storm zapped the coast. The these intense heatwaves and
resulting wildfires have already lightning storms.
burned more land than they did At the same time, I see another
in all of 2018 – and the fire season hope horizon of 10 to 20 years,
has only just started. which is about how long I think it
All this devastation comes on will take for California to deploy
top of the coronavirus pandemic, fire-reduction strategies like
which means that people fleeing controlled burns and housing
the heat and fires can’t huddle codes that mandate firebreaks
in shelters together without around cities and houses.
risking a superspreader event. That’s something policy-makers
So, the future here is looking could actually work on right now,
a little uncertain. and fixing it will help to improve
At times like this, I find myself the outlook on the 10,000-year
contemplating something I problem too. Which brings me
call a hope horizon, or how to a more important question:
many years it might take before “Alright for whom?”
everything becomes alright again. Plenty of people have never
22 | New Scientist | 26 September 2020
Views Aperture
24 | New Scientist | 26 September 2020
Red for danger
Photographer Josh Edelson
Agency AFP/Getty Images
THIS is what a US wildfire looks
like up close. Trees and embers
burn on the other side of the
Bidwell Bar Bridge, which spans
California’s Lake Oroville in
Butte county. These appear white
in the image, while the lights to
the right are from a small boat.
Thick smoke from the fire
is responsible for the red hues.
Smoke particles filter out shorter
wavelengths of light, such as blue
and yellow, while allowing longer,
redder wavelengths through.
Its peculiar beauty is a dire
warning about the power and
spread of wildfires in the region.
The Bear Fire in Butte County
is part of a major crisis in the
western US, where the most
severe wildfires in two decades
are destroying homes, landscapes
and livelihoods.
The first wildfires started in
California and Colorado in August.
So far, more than 10 states have
been affected, including
Washington and Oregon.
Collectively, some 18,000 square
kilometres have been scorched.
The smoke could also have
serious effects on health. The risk
of lung infections from inhaling
the smoke is made worse by the
other pressing threat, covid-19.
Wildfires serve as a stark
reminder of climate change.
Longer and drier summer
seasons coupled with strong
winds are largely to blame for
the unprecedented size and
scale of the fires. ❚
Gege Li
26 September 2020 | New Scientist | 25
Views Your letters
Editor’s pick conditions, with the associated Some networks are constructed Other reasons include ballots
thermal equilibrium of the planet by troubled people as survival arriving late or without the
A bit of fuzziness isn’t a that is so vital, will inevitably mechanisms when options they required certification.
big problem for physics consign our descendants to a would prefer are closed to them.
planet that just gets hotter and These might assist with their If, say, 10 per cent of Democrat
5 September, p 36 hotter. This will be a vastly bigger mental health, but they aren’t vote-by-mail ballots are rejected
From Rachael Padman, task than merely hitting the target their first choice. while 100 per cent of Republican
Cambridge, UK of no more than 1.5°C of warming in-person ballots are accepted,
In “Welcome to the fuzzy-verse”, by the end of the century. On the search for ways Donald Trump may have a
philosopher Eddy Keming Chen to end the pandemic significant advantage.
misstates the relationship of Granted, the temperature
physics and mathematics. The is rising gradually, but we need 5 September, p 7 Here is how to turn the
universe is what it is, and the to have the breadth of vision to From Jonathan Watson, tide against junk science
fundamental laws of physics see that the heating is relentless London, UK
are really just expressions of the and made faster and faster by Could there be an alternative to 22 August, p 36
patterns we observe there – they every puff of CO2 put into the a coronavirus vaccine to achieve From Tim Stevenson,
don’t explain anything. What they atmosphere. The time for action herd immunity if we could come Great Missenden,
can do is help us predict what else is now. The longer we leave the up with a test to predict who Buckinghamshire, UK
we might see if the pattern extends task, the harder and costlier it will would be asymptomatic? Many All strength to Stuart Richie in
to areas we haven’t yet looked at. become, but the price of not doing people would probably fall into his crusade against the perverse
this is incalculable. Let us set out this category. They might have motivations that lead to the
Separately, Chen seems the plan and get on with it. something in common other than publication of junk science, but
to identify the “Strong Past their underlying good health that an article or a book won’t rid us
Hypothesis” as a fundamental Many ways to look at the could be the basis of such a test. of this problem. It will take money.
law of physics – but it isn’t a law. impact of social contact
It is a hypothesis, something you If this were possible, then herd What might work would be for
can use as a starting point for 15 August, p 32 immunity might be achievable some considerably rich business
“what if” speculation but that with deliberate asymptomatic leader to set up a strikingly large
carries no predictive weight. From Terry Cannon, infection rather than vaccination. prize for the best paper that
Lewes, East Sussex, UK showed up a slovenly piece of
One might point to other “fuzzy” In his look at the benefits of “social Partial postal voting could research that had made headlines,
areas of modern physics, such as capital”, inspired by the pandemic yet upset the US election then give this paper publicity.
the inflation hypothesis: we are lockdown, David Robson argues
pretty sure there was inflation, but that “in recent decades, a raft 5 September, p 20 Motion sickness? Choose
we have no idea what might have of research has shown that From Ed Prior, your meal carefully
caused it and it has no predictive individuals with richer social Poquoson, Virginia, US
power. The universe will do what worlds tend to have better mental You report on an analysis that 22 August, p 47
it will do. Current models, patterns well-being and lower stress, and found voting by mail would From Alexander Pettigrew,
and theories have massive holes. to perform better at work”. have little effect on US election Newquay, Cornwall, UK
results. It seems to assume that As a long-time yachtsman, I found
It may be a surprise to a Does this research demonstrate Democrats and Republicans your article on motion sickness
non-physicist that we can’t clearly that the direction of would vote by post in similar very interesting. It reminded me
completely define the universe with causation is from good “social numbers. In fact, a recent poll of an age-old question among
mathematics. Physicists, however, worlds” to better mental health? indicates that a significantly sailors: if you think you might
are used to the idea that some Surely it is entirely plausible higher proportion of those who become seasick, what is the best
things may “just be”. A bit of fuzzy to argue for the reverse of this support the Democrats would thing to eat? The answer is peaches
uncertainty doesn’t fundamentally causation, or even a mutually choose to vote this way compared and cream, because they taste just
undercut the enterprise – it simply reinforcing circularity. with Republicans, who would as good on the way up as they did
reveals areas needing more work. rather turn out in person. on the way down.
I also think that the notion
No time to waste, let’s get of social capital used in the article In a recent New Jersey primary, From David Eadsforth,
on with restoring the sky is idealised and desocialised. thousands of postal votes were Alresford, Hampshire, UK
All social networks are embedded rejected, in part because officials When contemplating a rough
22 August, p 24 within systems of power, including decided voter signatures didn’t boat ride or some aerobatics,
From John Crook, class and gender, that are look enough like those held on file. many people will instinctively opt
Napier, New Zealand significant determinants of who to eat nothing beforehand, fearing
I was inspired by Graham Lawton’s can (or can’t) connect with who. motion sickness. Instead, they
description of Rob Jackson’s plea could try a remedy adopted by me
to restore the atmosphere to its Want to get in touch? and a number of friends decades
pre-industrial state. We absolutely ago: scoff a couple of large, sugary
must do this. Any plan or course Send letters to [email protected]; doughnuts about an hour before
of action that falls short of full see terms at newscientist.com/letters the activity. It works wonders. ❚
reinstatement to pre-industrial Letters sent to New Scientist, 25 Bedford Street,
London WC2E 9ES will be delayed
26 | New Scientist | 26 September 2020
Signal Boost
Welcome to our Signal Boost project – a weekly page for charitable
organisations to get their message out to a global audience, free of charge.
Today, a message from Humanity First
Humanity First is a multi-sector NGO, UK RESPONSE University of Oxford
responding when disasters strike as well as • In the UK, we support communities up and • The Global Economy & Covid by
working on development projects. From
installing water wells, providing agricultural down the country, including our new Foodbank Professor Atif Mian, Princeton University
support and running medical camps to building in Mirfield, Yorkshire. • Cancer Care in the Covid era
schools and hospitals, we strive to bring • We partner with International Health Partners
sustainable provision, access to healthcare and (IHP) to donate and deliver essential PPE to our by Royal Marsden Cancer experts.
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regardless of race, religion or creed. • Our national support line helps to signpost WHAT NOW?
people to services relating to the Coronavirus The covid-19 crisis has hit many charities
We have been at the forefront of fighting (Covid-19) pandemic financially with a massive dip in donations.
covid 19 globally with trained volunteers More than 53% of charities have reported a
including medical professionals and disaster THOUGHT LEADERSHIP drop in donations, however most have reported
responders. At the same time, we have pushed on Thought a spike in demand for their services. Despite the
Leadership with our Webinars including on: different streams of funding made available by
GLOBAL COVID RESPONSE • Humanitarian Ethics in Covid by Dr Hugo Slim the UK government, many charities are still
So far in the fight against covid 19 struggling.
our 3487 unpaid volunteers across the formerly of ICRC and now at Oxford.
world have: • Mental Well Being & the Covid Crisis Humanity First’s huge volunteer base ensures
• Distributed 185,140 PPE items great efficiency and our pound or dollar goes
• Supported 148 hospitals by Professor Jeremy Howick, Director much further. All our management team here
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Views Culture
How our brains make us
Livewired reveals the intriguing reasons why a 6-year-old can thrive with half a
brain and why some people who are blind can echolocate, finds Clare Wilson
Book Obviously, since we can’t
dissect the brains of living people,
Livewired: The inside story it is very hard to observe those
of the ever-changing brain transformations at the molecular
and cellular level. Yet we can
David Eagleman clearly see their effects on
Canongate Books behaviour and abilities. It is why
we are able to learn new skills,
IMAGINE if your 6-year-old ANDRIY ONUFRIYENKO/GETTY IAMGES even in later life, and why some
son needed surgery to remove people who are blind can learn to
a staggering half of his brain. That In extreme cases, this brain Our brains can remake echolocate in a similar way to bats.
was what faced Matthew, a boy
with a rare condition triggering resculpting is visible at the themselves to adapt to Brain scans show that in people
many epileptic seizures a day and who lose their sight, the part of the
that could only be treated with anatomical level through changing circumstances brain that usually receives signals
this drastic surgery. When he woke from the eyes instead starts
up afterwards, he was incontinent post-mortems or scans. processing input from their ears
and couldn’t walk or speak. and their sense of touch. This
Professional musicians starts to happen even in people
Yet with daily physical and who are blindfolded for a few days.
language therapy, Matthew develop a small bulge on a ridge
regained these abilities. In three Eagleman and his team are
months, he was almost back to of their motor cortex – a part exploiting this flexibility by
normal, minus the seizures. making devices that let people
Now an adult, brain scans show of the brain that controls receive sensory information in
half of Matthew’s skull as a new ways. They have built special
black void, yet the only visible movement – revealing the vests and wristbands for people
effects are his slight limp and a who are deaf. These capture sounds
little clumsiness in his right hand. effects of thousands of hours and translate them into vibrations
through pads next to the skin.
How could someone lose half moving their fingers in complex Eagleman envisages that, one day,
of their brain and recover almost such devices may not only replace
all of their functioning in three choreographies. It is reminiscent “DNA is only half of lost senses, but also create new
months? For neuroscientist David of the way a large bicep may ones. For instance, a politician
Eagleman at Stanford University what makes you who giving a speech could use a vest to
in California, this demonstrates reflect the hours spent at the gym. monitor its reception on Twitter
one of the brain’s most remarkable Research on animals shows you are – the rest is all and dial it up or down accordingly.
qualities: neuroplasticity, or the
ability to remake itself in response that such a cortical bulge arises the experience you The nervous system seems to
to changing circumstances. accept such tinkering surprisingly
from rewiring at multiple levels. have with the world” quickly. Eagleman has a good
In Livewired, Eagleman explains example: can you guess how
why this ability is so fundamental Not only is there the growth long it takes people to get used
to who we are that James Watson to manipulating three arms in
and Francis Crick’s claim to have of new synapses (connections virtual reality, with the third
discovered the “secret of life” with sprouting from the middle of
their work on DNA is only half of between brain cells) but there their chest? Just 3 minutes.
the story. The rest of what makes
you who you are is “every bit are also changes to the molecular Yet neuroplasticity has its
of experience you have with the limits. As we get older, our brains
world: the textures and tastes, the machinery of those synapses. become less flexible and more
caresses and car accidents, the stable. Older people can still learn
languages and love stories… all of Neurons can sprout more a language or musical instrument,
which sculpt the vast, microscopic but the operation experienced by
tapestry of your brain cells and branches, and sometimes Matthew would be disastrous – it
their connections,” he writes. isn’t generally recommended for
whole new neurons can form. children aged 8 or older.
28 | New Scientist | 26 September 2020
Don’t miss
Utopian nightmare
A thrilling TV series resonates with the threats
of our pandemic times, finds Gege Li
A less-plastic brain might sound TV an upcoming comic convention Visit
bad, but as Eagleman writes: “If in Chicago. This is the news the Paradise Lost brings
plasticity didn’t decline, you would Utopia group has been waiting for. artist Jan Hendrix to
not lock down the conventions London’s Kew Gardens
of the world. Preserving Adapted by Gillian Flynn At first, the group’s members from 3 October with
total flexibility would retain Amazon Prime Video seem like the conspiracy an exhibition mourning
the helplessness of an infant.” (from 25 September) theorists other Utopia fans take Kamay Botany Bay in
them for. But when the comic is Australia. Kew founder
Prematurely locking down “WHAT have you done today to successfully auctioned, things Joseph Banks collected
those conventions may explain earn your place in this crowded take a sinister turn, with the plants from it in 1770,
the phenomenon of synaesthesia, world?” This ominous question – arrival of the emotionally when it was pristine.
in which people have fixed frequently posed in the US TV detached Arby (played by
associations between unrelated series Utopia – hangs over the Christopher Denham) and his Read
stimuli – for instance, the letter “A” world envisaged by the show. partner Rod (Michael B. Woods). The Story of Evolution
may always seem blue to some. in 25 Discoveries
Eagleman believes synaesthesia The series has been adapted They are also hunting Utopia, is palaeontologist
stems from the early formation of by Gillian Flynn (screenwriter and one of its not-so fictional and geologist Donald
memories that are too stable. For for hit film Gone Girl) from the characters, Jessica Hyde Prothero’s entertaining
instance, he thinks alphabet-colour 2013 British TV series of the (Sasha Lane). So they are guide to the past,
associations, a common form of same name, created by Dennis tracking down everyone at the present and future
the condition, may sometimes Kelly. It follows five strangers auction who set eyes on the of living things – with
occur because someone can’t who connect online over their comic, including the group. nature’s more bizarre
forget the colours of the first obsession with an elusive aspects to the fore.
letters they learned as a child. comic called Utopia. But these Meanwhile, a mysterious flu
aren’t your typical comic book virus is killing schoolchildren in Listen/watch
In a study of more than 6500 enthusiasts and this may be isolated pockets across the US. Objects of Crisis is a
synaesthetes, Eagleman and his no real Utopia. At the centre of this storyline hybrid series of Zoom
team found that the letter-colour is a doctor, Kevin Christie podcasts in which
pairings are usually random, but For complex and plot-spoiling (John Cusack) of Christie Labs, British Museum director
for 15 per cent of people who were reasons, the group is convinced a pharmaceuticals-turned-food Hartwig Fischer reveals
young children in the 1970s and the comic contains hints about company now rolling out its own objects – from a tiny oil
1980s, they follow a telltale future disasters and that finding version of lab-grown meat. lamp to a Buddhist prayer
pattern: A is red, B is orange, C is it will shed light on what or manuscript – that helped
yellow, D is green, E is blue, F is who will be responsible. As the show develops, with us ride out past crises.
purple and then the cycle repeats images of disasters like fires
through the alphabet. This just The series begins when and melting ice caps in the title 26 September 2020| New Scientist | 29
happens to be the pattern of a a young couple discover the sequence that may foreshadow
Fisher Price alphabet magnet set original Utopia manuscript. what is to come, the group’s
that was popular in that period. Oblivious to its true value, they original suspicions about Utopia
know enough to try to sell it at seem less and less fantastical.
It is unclear how he extends
his idea to explain less common Packed with thrills and some
forms of synaesthesia, like the violence, Utopia lives up to what
association of sounds with Flynn envisioned: “Gnarly, nasty,
colours, but the idea seems raw and unnerving”. Perhaps
plausible for letter-colour pairings. what conveys this best is that
it draws convincing parallels
However, most of the book with real and tangible threats,
isn’t about Eagleman’s research, including the coronavirus
but is a broader overview of this pandemic and runaway fires.
important field of neuroscience. That is what makes the idea of
I finished Livewired feeling that needing to earn your place – left
I had learned a lot about the brain, hanging for future episodes – all
without it ever being too dry or the more disturbing. ❚
academic. Eagleman brings the ELIZABETH MORRIS/AMAZON STUDIOS
subject to life in a way I haven’t E J SCHEMPH; THE TRUSTEES OF THE BRITISH MUSEUM
seen other writers achieve before. ❚ From left: Becky (Ashleigh
LaThrop) and Jessica Hyde
(Sasha Lane) in Utopia
Views Culture
The film column
Deathlessness isn’t the same as life Hope Frozen is a painful documentary
that asks deep questions about life and death technologies through the
story of Einz, a terminally ill baby girl, and her family, says Simon Ings
Einz’s mother
remembering her
2-year-old daughter
Simon Ings is a novelist and NETFLIX and consigned her to limbo.
science writer. Follow him on Sahatorn and Nareerat,
Instagram at @simon_ings THE world – including this hour after hour of the little girl’s
meanwhile, are both working
Film magazine – hasn’t shied away life. She was – and is still, in Pailin engineers, and Sahatorn says
they have put their faith in
Hope Frozen: from expressing opinions Wendel’s ravishing, painful science. Matrix, caught in the
A quest to live twice middle as a novice monk and
about the Alcor Life Extension documentary – captivating. a gifted student of science,
Pailin Wedel carries the weight of this dilemma
Netflix Foundation, the US non-profit Just before her third birthday, with admirable fortitude. At the
end of the film, my strongest
Simon also founded by Fred and Linda Einz died of ependymoblastoma. wish was that he would one day
recommends... escape these competing pressures
Chamberlain in 1972 to freeze After 10 surgical operations, and live his own life.
TV
corpses and body parts in the hope 12 bouts of chemotherapy and Yet anyone hoping for a
Be Right Back uniquely Buddhist take on the
of one day resurrecting the dead. 20 rounds of radiation therapy, transhumanist promise will be
Owen Harris disappointed. There is very little
Bereaved and pregnant, Most observers are content her family and the doctors knew to distinguish Buddhist objections
Martha (Hayley Atwell) from wider unease about not
receives a robot replacement with interrogating Alcor’s bizarre leaving the dead to rest in peace.
for her late boyfriend in
a devastating episode mission by asking if technologies “Some critics in Wedel lets the family speak for
of Black Mirror, Charlie for resurrection will ever be viable. Thailand, a mostly themselves. Inevitably, they come
Brooker’s sci-fi anthology. This, of course, is a non-question: close to revealing the faultlines in
who knows what is around the Buddhist country, felt their choices, especially Sahatorn.
Film “I don’t care that people say I can’t
corner? The successful freezing the family had thwarted move on,” he says. “I don’t care
Marjorie Prime because it’s true.” When the
and thawing of a whole rabbit brain Einz’s reincarnation” family visits Alcor, Sahatorn loses
Michael Almereyda himself in the technical details
Jon Hamm plays an AI in 2016 shows how careful we while Nareerat weeps quietly.
bringing comfort to Marjorie
(Lois Smith), a woman must be in dismissing such ideas. it was coming: this highly Hope Frozen leaves me worrying
with Alzheimer’s. The film, that by denying themselves some
based on Jordan Harrison’s Mark O’Connell’s approach in aggressive brain cancer is a killer. form of spiritual afterlife for Einz,
play, manages to be both her relatives have lost her twice
mind-bending and touching. To Be a Machine was more fruitful: At the eleventh hour, Sahatorn over. They have lost her physical
form and now they can’t even
he asked why people would want persuaded his family that on animate her spirit in their
imaginations. “For sure, we are
to freeze themselves or their loved her death, her brain and some of headed towards deathlessness,”
says Sahatorn, proselyting for
ones at all. Hope Frozen, filmed her tissue should be frozen and the strange scientistic faith that
is his defence against grief.
in Thailand at around the time transferred to Alcor’s Arizona
He isn’t wrong: from cryonics
O’Connell was writing his book, facility. Einz became the youngest to CRISPR gene editing, there is
no shortage of effort going into
goes some way towards an answer. person to be cryonically preserved. avoiding death. As Wedel’s
upsetting film reveals, however,
Matheryn, nicknamed Einz, was The story created a media storm in deathlessness isn’t life. ❚
born in 2013 to parents Nareerat Thailand. In the film, some critics
and Sahatorn Naovaratpon. For in this mostly Buddhist country
more than two years, they and complained that her family had
their besotted son, Matrix, filmed prevented Einz’s reincarnation
30 | New Scientist | 26 September 2020
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Features
The ultimate battery
A forgotten kind of nuclear power could create incredibly
long-lasting batteries, says David Hambling
T HE VOYAGER probes blasted off in by allowing charged ions to flow. But there
1977, beginning what would prove to is greater power to be had if we look beyond
be the longest journeys ever taken by chemistry, inside the atom itself.
objects from Earth. The two spacecraft have
now left the solar system and Voyager 2 is Each atom consists of a nucleus made of
sending back measurements of interstellar particles called protons and neutrons orbited
space. As achievements go, it ranks among by a cloud of electrons. These protons and
humanity’s most profound. But a crucial neutrons are usually melded together in
aspect of that success is seldom celebrated: the extreme temperature and pressure inside
those probes sure do have good batteries. a star, and if you delve into an atom’s nucleus
in the right way, you can extract some of that
In the day-to-day grind of life, batteries awesome power. The main way we do that
never seem to last long enough. We must is nuclear fission, in which a nucleus releases
juice up our phones every day, laptops neutrons that can then split more atoms,
seem to constantly thirst for their power causing a chain reaction that releases huge
cables, electric cars only go so far before amounts of energy. That is the way the
they fizzle out. It is enough to make you world’s 440-odd nuclear energy plants
want a new type of power supply. work. There is also nuclear fusion, which is
potentially much more powerful, but relies
We may be edging closer to exactly that. on smooshing together nuclei in a controlled
The Voyager probes employ a weak nuclear fashion that we haven’t yet mastered.
power source that, being radioactive, is
considered dangerous to use on Earth. But The Voyager probes get their power in
there is a closely related form of energy that a different way: they make use of natural
packs even more of a punch and could work radioactivity. Some atoms are unstable
safely in your average car. It is a long shot. and spit out a chunk of matter and energy
The last time this outlandish technology now and again. It could be a cluster of two
was seriously considered, 20 years ago, it protons and two neutrons (alpha radiation),
ended in a broiling controversy. However, an electron (beta radiation) or raw energy
now the US Army has it firmly in its sights in the form of gamma rays.
and has conducted an experiment that
might just give it a new lease of life. We can’t predict when a specific atom
will decay in these ways, but we can say
Most of the ways we store energy involve how long it will take for half of the atoms
chemistry. When we burn petrol in a car in a lump of radioactive material to do so.
engine, we are releasing energy stored in This is its half-life and the number can vary
chemical bonds. Similarly, lithium-based widely. Some radioactive materials vanish
batteries in devices like mobile phones work in seconds. Plutonium-238 has a half-life >
32 | New Scientist | 26 September 2020
SEÑOR SALME
26 September 2020 | New Scientist | 33
of 87.7 years, which is why it was chosen as the NASA/JPL-CALTECH
power source for Voyager 2. The plutonium
dribbles out a stream of alpha particles, Voyager 2 was energy but stable. You could have this sitting
generating heat that is turned into electricity launched more than safely in a container for a long time because
by the probe’s three roughly suitcase-sized 40 years ago, yet its it emits barely any radiation. When you need
radioisotope thermoelectric generators. battery is still going some power, you convert a small amount
of it into its ground state, which is less stable
Radioactivity has a bad reputation, but to make the hafnium isomer meant it could and begins to radioactively decay quickly.
not all types are equal. Gamma radiation only be produced in small quantities at great This gives you a generator akin to the one
penetrates human tissue most deeply and expense. The episode became known as the in Voyager 2, but which can be cranked up
is dangerous. Beta radiation isn’t so bad. “hafnium controversy”. in power at will.
Alpha radiation doesn’t get through the skin,
so it is only damaging if it gets loose inside Other high-energy isomers might get James Carroll at the US Army Research
you. In fact, pacemakers were powered with around the problems. For example, Laboratory in Adelphi, Maryland, has been
well-contained radionuclide thermoelectric tantalum-180m occurs naturally, if rarely, investigating whether interconverting
generators until the early 1970s. in mineable tantalum deposits. Silver-108m isomers in this way is possible. One potential
produces beta radiation, which is less way to do it, first proposed in 1976, involves
The concept that the US Army is eyeing up dangerous and easier to tap. None of this firing an electron at an isomer and it being
is a kind of nuclear power that blends some makes isomer power a safe bet, but the absorbed into an orbit around the nucleus.
of the best bits of the other types – it could be pay-off from creating an effectively unlimited This prompts the protons and neutrons to
powerful, safe and long-lasting. It depends energy source may make it worthwhile. A rearrange. It is called nuclear excitation by
on the fact that the protons and neutrons of a similar rationale applies to the £11.6 billion electron capture (NEEC).
particular element can be clustered together being spent on the ITER fusion reactor in
in different arrangements in an atomic France, even though it is intended merely Carroll and his team used a particle
nucleus. These are called isomers and each as a technology demonstration and won’t accelerator at Argonne National Laboratory
has a different energy. Atoms usually reside generate power. near Chicago to create a beam of
in what is normally their most stable isomer, molybdenum-93m atoms, with a half-life
the ground state. Higher energy isomers Collins’s approach was to get all the of about 7 hours. This beam was travelling
tend to quickly rearrange themselves back pent-up power of an isomer out in one at about 10 per cent of the speed of light,
to this state. But there are a few high-energy go. But there is, in principle, a different fast enough to strip away some of the
isomers that hang around for a long time. and arguably more useful method. We have
known about it for decades, it just hasn’t
Pent-up energy been properly pursued.
In 1998, Carl Collins at the University of Texas Imagine you have a lump of radioactive
used a particle accelerator to prepare one isomer that, like hafnium-178m2, is high
of these stable high-energy isomers, called
hafnium-178m2 (the m2 notation means
this is the second isomer of hafnium-178).
He then fired X-rays at its nucleus and
claimed that this shifted the nucleus to its
ground state, releasing a burst of gamma
rays. These would be hard to tap as an energy
source because they are so dangerous, but
Collins saw it as proof of principle that
nuclear isomers could be useful power
sources. He thought they could even be
used as a new type of nuclear bomb.
Many scientists ridiculed Collins’s claims,
arguing that he had to put in more energy to
trigger the isomer shift than he got out. Plus,
the fact that you need a particle accelerator
34 | New Scientist | 26 September 2020
“Isomers blend atoms’ electrons. It was then smashed into a battery. The Polish team is looking at
the best bits target, which injected electrons back into the rhenium-186m and americium-242m
of other types nuclei, while nudging them into a less stable among other isomers.
of nuclear isomer. This isomer decayed so quickly that
energy. They the researchers couldn’t observe it. But they At the moment, there is no sense of how
could be safe, inferred it was created by the gamma rays isomer shifting could be done at a smaller
powerful and it produced. The work, published in 2018, is scale than in a particle accelerator. Still,
long-lasting” the first time NEEC had been demonstrated. there is ample drive to get isomer batteries
to work because they would pack gigantic
Army vehicles like “The experiment has been a significant amounts of energy into a small volume.
the SMET might step forward, but the jury is out regarding “Isomers can store energy with a capacity
one day be able to whether or not it is a breakthrough for NEEC,” of up to over gigajoules per gram,” says
run for months on says Philip Walker, who studies nuclear Rzadkiewicz. That’s a million times more
an isomer battery isomer physics at the University of Surrey, than lithium-ion batteries, and tens of
UK. This is largely because there is dispute thousands of times more than petrol.
US ARMY over how much energy can be wrung out
of isomers. Carroll’s figures suggest that Risk and reward
the process could produce 5 joules of energy
for every joule put in, assuming 1 per cent Carroll says an uncrewed army vehicle
of atoms undergo NEEC. known as a SMET, used to carry soldiers’
equipment, could run for 163 days on
Adriana Pálffy at the Max Planck Institute 1 kilogram of americium-242m. The current
for Nuclear Physics in Heidelberg, Germany, version runs for three days on 20 litres of
isn’t so sure. Her calculations suggest petrol. Drones or robot submarines could
that a billion times fewer atoms should also be given isomer energy sources. It is
be depleted through radioactive decay. easy to see why the US Army is interested.
If true, that raises questions about where
the energy that Carroll saw is coming from. Safety is going to be a concern for anything
“The experimental results may be valid, with “nuclear” in its name. And if isomer
but their interpretation of what happened power produces gamma rays, that will
in the process cannot be correct,” says Pálffy. preclude its use. But if isomers can be found
that emit beta or alpha particles, it could
Carroll admits that isomers are far from be feasible. Plenty of people work close to
being of practical use as batteries. But the stores of materials used for radiotherapy
arguments that applied after Collins’s work and diagnostics. “The amounts of radioactive
still apply: there are other isomers that could material needed for a battery are probably
be more accessible and easier to harness. The less than the material routinely shipped
trouble is that the exact properties of isomers around hospitals,” says Patrick Regan at
are tough to calculate, and we won’t know the University of Surrey.
how suitable they are until we try them.
Isomer power is the longest of long
That is exactly what the US Army now shots. But then many of our greatest
wants to do. The Army Research Laboratory achievements seemed that way at the
is sponsoring Poland’s Department of beginning. When the space race began,
Nuclear Techniques and Equipment at Swierk who would have thought that, just decades
to explore the science of isomer depletion. later, we would have sent a probe beyond
The team is led by Jacek Rzadkiewicz and has the edge of the solar system? ❚
access to the Polish MARIA experimental
nuclear reactor, which can produce a variety David Hambling is a
of different isomers. “The goal of the project technology journalist
is to learn the nature of the process of based in London
charging isomers and their discharge on
demand,” says Rzadkiewicz. In other words, 26 September 2020 | New Scientist | 35
find out which isomers would make a good
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Features Cover story
Evolving
evolution
Our modern conception of
evolution started with Charles
Darwin and his idea of natural
selection – “survival of the fittest” –
to explain why certain individuals
thrive while others fail to leave a
legacy. Then came genetics to
explain the underlying mechanism:
changes in organisms caused by
random mutations of genes.
Now this powerful picture
is changing once more, as
discoveries in genetics, epigenetics,
developmental biology and
other fields lend a new complexity
and richness to our greatest theory
of nature. Find out more in this
12-page feature special.
38 | New Scientist | 26 September 2020
TIM MCDONAGH 1
GENES AREN’T DESTINY
The principle of genetic plasticity
I N 1990, an international group
of scientists embarked on one of the
most ambitious research projects ever
undertaken. They would sequence the
entire human genome, determining
the order of the 3.3 billion base pairs
that code for the genes that make the
proteins that each of us are built from.
There was huge excitement at the prospect
of decoding the “blueprint” of humanity.
Given the complexity of our species, our
genome was expected to contain at least
100,000 genes. What makes us human
would finally be laid bare.
It didn’t quite work out like that.
The Human Genome Project was a
resounding success, publishing its
results in 2003, two years ahead of target.
However, it revealed that humans only
have around 22,000 genes, which is
about the same number as other
mammals. Meanwhile, the blueprint
itself turned out to be encrypted in
ways we are still trying to crack.
The same thing is true of us that is
true of every species: our DNA can be
expressed in myriad different ways
depending on which combination of
sequences is activated. It is this, not the >
26 September 2020 | New Scientist | 39
number of genes in the genome, Genetic flexibility allows any UWE GRUN/ALAMY 2
that creates the complexity of life. paper wasp to become queen
EVOLUTION SHOWS
The more we learn about genetics, INTELLIGENCE
the clearer it becomes that “genetic
determinism” – the idea that genes and Natural induction
genes alone fix our destiny – is a myth.
A given set of genes has the potential HOW has life on Earth evolved such a
to produce a variety of observable dazzling array of beauty and complexity
characteristics, known as phenotypes, in the 3.8 billion years since it emerged? The
depending on the environment. An standard answer is that the sheer abundance
Arctic fox changes its coat colour with of life forms means a huge number of random
the seasons. The presence of predators genetic mutations are happening all the time,
causes water flea Daphnia longicephala allowing natural selection to test many
to grow a protective helmet and spines. prototypes at once (see “The standard model
of evolution”, page 45). But some researchers
The power of flexibility suggest a radical twist to that explanation.
They argue that evolution can learn.
Even a change in social environment can
prompt a shift. In the European paper wasp Their inspiration comes from computer
(Polistes dominula), for example, when the science. Computers can mimic intelligence
queen dies, the oldest worker transforms using algorithms: iterative rules that
herself into a new queen. But she isn’t combine existing knowledge with fresh
the only one to respond. Seirian Sumner information to generate novel outputs. A
at University College London and her simple algorithm called Bayesian updating,
colleagues found that the death of a colony’s for example, starts with many hypotheses
queen results in temporary changes in the and homes in on the best ones as new
expression of genes in all workers, as though information becomes available.
they are jostling genetically for succession.
This flexibility is key to the survival of the Likewise, natural selection incorporates
colony and the species, says Sumner. new information from the environment to
favour the best-adapted organisms. Richard
“EVOLUTION’S SIMPLE Watson at the University of Southampton,
PROCESSES MIGHT FORM UK, decided to look at the mechanisms
A LEARNING MACHINE” involved to try to work out what is going on.
In evolutionary terms, information about the
The power of genetic plasticity can be past is carried in genes inherited by the
seen in the humble house finch. In the past offspring of fit individuals. But a relatively
50 years, it has colonised the eastern half of recent insight is that genes don’t code “for”
North America, moving into habitats ranging particular traits. They are team players, and
from pine forests near the Canadian border their activity is regulated by other genes to
to swampland in the Gulf of Mexico. The create a network of connections. Natural
finch’s underlying developmental plasticity selection favours those connections that
provided the raw material from which work best. This, Watson realised, is just like
novel features evolved, including a range how a brain learns. Brains consist of networks
of new colourings and other physical and of neurons whose structure is shaped by
behavioural traits, says David Pfennig at the learning because the more a connection is
University of North Carolina at Chapel Hill.
“Stop thinking about this as being like genes
or environment, because it’s a combination
of the two,” he says. Carrie Arnold
40 | New Scientist | 26 September 2020
used, the stronger it becomes. Sure enough, Kenya’s Samburu people show TON KOENE/VWPICS/SCIENCE PHOTO LIBRARY
when Watson and his colleagues built a how cooperation evolves
computer model that took account of the superorganism. And among any sexually
networked nature of genes, they found it could 3 reproducing species, parental care helps
evolve to learn and remember solutions to individuals propagate their genes.
problems with just a simulacrum of natural MOVE OVER, SELFISH GENE
selection to reinforce the best attempts. But kin selection cannot explain why
Cultural group selection humans are so nice to strangers. One idea is
Brains don’t just learn specific solutions to that we have evolved to be super-cooperative
particular problems: they also generalise to EVOLUTION traditionally has a problem because, over time, more cooperative groups
solve problems they have never encountered. with Good Samaritans. If only the fittest have outcompeted less cooperative ones.
They do this by recognising similarities individuals survive, then those who are nice But there generally isn’t enough genetic
between new challenges and past ones, to others at their own expense will surely be variation between groups to allow natural
and then combining the building blocks weeded out. Yet cooperation is widespread selection to favour more cooperative ones.
of previous solutions to come up with in nature, from plants that alert each other to
novel ones. This is called inductive learning. danger and colonial insects that work as one Some researchers think the solution lies
Can gene networks do induction too? to dolphins cooperating to round up fish. in an idea called cultural group selection.
Forget shared genes, they argue: selection
Watson and his colleagues argue that A decades-old idea called kin selection can can favour cooperative groups if the people
they can. The key, they say, is that energy is explain some of this: if organisms have within them share enough culture. The idea
required to connect genes, because proteins enough DNA in common, then they can is controversial because to work it requires
must be produced to achieve this. So, for further their own selfish genes by helping that groups remain culturally distinct. As
efficiency, evolution favours networks with one another. Bees, ants and wasps have a critics point out, people tend to migrate
fewer connections, which are loosely linked system of reproduction called haplodiploidy, between groups, which should homogenise
with other subnetworks. These building which leaves colony members so closely ideas and customs. Those who back the
blocks can be recombined in different ways related that they act almost as a single concept counter that groups have ways to
to generate novel solutions to the problems retain their distinct culture, including a
that challenge life. Thus, evolution’s simple process called norm enforcement. Put
processes form an inductive-learning simply, if someone migrates into a new
machine that draws lessons from past cultural group, they are pressured into
successes to improve future performance. following the local rules because failing
to do so leads to punishment.
This conception of evolution has
far-reaching implications. For a start, Earlier this year, Sarah Mathew and
it can explain how entire ecosystems Carla Handley at Arizona State University
evolve to be well-adapted despite natural published a pioneering field study testing
selection favouring fit individuals, not fit the idea. They sampled 759 people from
communities. Think of the connections four pastoral ethnic groups in Kenya – the >
between organisms within an ecosystem as a
network, and they too can learn by induction, 26 September 2020 | New Scientist | 41
as Watson and his Southampton colleague
Daniel Power have demonstrated using
computer modelling. “An ecosystem can’t
be adapted by natural selection, but it can be
adapted by natural induction,” says Watson.
This raises an intriguing question. If
natural induction isn’t about survival of the
fittest, what is it about? “Maybe, evolution is
less about outcompeting others and more to
do with co-creating knowledge,” says Watson.
That really is a radical idea. Kate Douglas
Turkana, Samburu, Rendille and Borana – 4 created when food was scarce became
who compete intensively for land, water and associated with a high incidence of metabolic
livestock. The pair estimate that genetic THERE IS MORE diseases in times of plenty.
differences between individuals from TO INHERITANCE
different groups was generally less than 1 per THAN JUST GENES Subsequent studies in plants and animals
cent. Cultural practices and beliefs varied suggest that epigenetic inheritance is more
much more, by 10 to 20 per cent. People Epigenetic marks common than anyone had expected. What’s
cooperated most with members of their own more, compared with genetic inheritance, it
group, as cultural group selection predicts, IF GENES form the words in the book of life, has some big advantages. Environments can
and to a lesser extent with members of other then epigenetic marks are the punctuation. change rapidly and dramatically, but genetic
groups whose norms most closely matched These chemical tags affect which genes are mutations are random, so often require
their own. That makes sense if culture rather turned on and off in an organism. They are generations to take hold. Epigenetic marks,
than genetics is what matters. “I think this created in response to changes in conditions by contrast, are created in minutes or hours.
is one of the most explicit tests of cultural within cells or the external environment, And because they result from environmental
group selection theory so far,” says Mathew. such as temperature, stress or diet. Since their change, they are often adaptive, boosting the
discovery in the 1950s, scientists had thought survival of subsequent generations.
Not everyone is persuaded. Max Krasnow
at Harvard University sees no theoretical flaw Take the pea aphid. It is capable of both
with the idea, but says that some of his sexual and asexual reproduction, and comes
research undermines it. He has found that in two varieties: winged and wingless. When
people don’t just enforce the rules within scientists exposed a group of genetically
their group, but also punish people from identical pea aphids to ladybirds, the
other groups who fail to follow their own proportion of winged aphids increased from
group’s norms. Mathew counters that it is a quarter to a half. This adaptation, which
reasonable to enforce the norms of outsiders helped them escape the predatory ladybirds,
as a step towards incorporating them into persisted for 25 generations. The aphid DNA
your cultural group. “This is often how didn’t mutate, the only change was epigenetic.
empires expand,” she says. Colin Barras
Epigenetic bequests aren’t always
beneficial. Experimenting with nematode
“COMPARED WITH GENETIC
INHERITANCE, EPIGENETICS
HAS BIG ADVANTAGES”
Plants can vary their fruit size BLICKWINKEL/ALAMY that all epigenetic marks were erased before worms, Martin Lind at Uppsala University in
because of epigenetic marks genes are passed from parents to offspring. Sweden and his colleagues have discovered
A dark episode in human history provided that the key factor is whether environmental
42 | New Scientist | 26 September 2020 an early hint that this might not be so. conditions remain stable. If they change,
then adaptations may be detrimental to
In late 1944, as retaliation for a Dutch subsequent generations – as happened with
rebellion against German occupiers, the descendants of the Dutch Hunger Winter.
Nazis cut off food and fuel supplies to the
Netherlands. By the time the country was The extent of epigenetic inheritance is
liberated, adults were subsisting on an contested. Some sceptics point out that,
average of 580 calories per day. Children born during mammalian reproduction, the
to women who were pregnant during this creation of sperm and egg cells involves
time were small and had low birth weights. erasing epigenetic markers. Others argue that
Surprisingly, though, later in life they had epigenetic transmission across generations
unusually high levels of obesity, diabetes is extremely widespread and useful. In plants,
and schizophrenia. So, too, did their children. for example, it can account for differences
in fruit size, flowering time and many other
It makes sense if epigenetic marks are survival-boosting traits. Carrie Arnold
being passed down the generations. Marks
The African elephant is now WIM VAN DEN HEEVER/NATUREPL.COM that biologists often have two objectives
seen as two species not one in mind when they define species: one
is the traditional desire to divide nature
5 FOR most of history, we have had little into easily recognisable packages; the
trouble defining species. There was a second is to explain, in evolutionary terms,
SPECIES DON’T REALLY EXIST general assumption that a finite number how those species came into existence.
of distinct forms of life had existed “Humans have conflicting motivations
Taxonomic anarchy unchanged since creation, each sitting in a towards species,” he says.
clearly defined pigeonhole: human, housefly,
hawthorn and so on. Within the past few Some researchers argue that these
centuries, and particularly after Darwin, two objectives can never be achieved
evolutionary theory has emerged as a simultaneously. Down the decades,
more satisfactory way to explain how species biologists have come up with a few dozen
came into existence. Yet in doing so, it has clever ways to define species. Some make
made species far harder to define. it easy to classify the organisms we
encounter – by their physical appearance,
There are several aspects to the problem. for example – but tell us little about the
One is that if we accept the idea of species evolutionary process itself (see “Sadistic
evolving from other species, then we must cladistics”, page 49). Other definitions get to
allow that an ancestral species can gradually the heart of how species come to exist, but
morph into one or more descendants. We can be difficult to use in the real world.
would still like to place organisms in discrete
categories, but doing so is difficult if species Hybrid bonanza
blur into one another through time. “As we
have come to terms with evolution, it has In principle, advances in genetic sequencing
highlighted a problem with the machinery in could have helped by indicating how
our heads we use for classifying,” says Frank genetically distinct different groups of
Zachos at the Natural History Museum of organisms are and how long ago lineages
Vienna in Austria. diverged. But sequencing has arguably
made the problem worse by revealing that
For Jody Hey at Temple University in interbreeding – more technically,
Philadelphia, the more important problem is introgression – between closely related
“species” is common across the tree of
life. “It does seem to be the rule, not the
exception,” says Michael Arnold at the
University of Georgia in Athens. Indeed,
evidence of introgression stretches right to
our front door: our ancestors interbred with
various ancient hominins that might, in the
eyes of some, count as distinct species.
Another problem is that looking at genes
rather than observable features makes it
easier to find new species, leading to what
some researchers have called taxonomic
anarchy. For instance, a biologist can argue
that a previously recognised species should
really be split into two or more “new” species,
as happened when genetic analysis of the
African elephant led to its being separated
into savannah and forest-dwelling species.
To help add more rigour to the business of
defining new species, earlier this year Zachos
and other biologists proposed establishing
the first single authoritative list of the world’s
species. “Species” itself will remain a slippery
concept, but at least we could all agree
on where to draw the lines. Colin Barras
26 September 2020 | New Scientist | 43
6 ROLF NUSSBAUMER/NATUREPL.COM ahead of his time. Today, there is evidence A beaver’s dam is both a
of Lamarckian evolution – of a sort. Take the product and cause of evolution
ADAPT FIRST, Mexican spadefoot toad (Spea multiplicata).
MUTATE LATER It breeds in ponds that appear after summer 7
monsoons and the newly hatched tadpoles
Neo-Lamarckian adaptation typically survive on a diet of algae and WE CAN SHAPE OUR
bacteria. However, should tadpoles find OWN EVOLUTION
IN THE 1880s, August Weismann began themselves in a pond where fairy shrimps are
cutting the tails of mice. He wasn’t sadistic, available, they adapt to take advantage of the Niche construction
he just wanted to find out whether animals more nutritious fare, developing larger jaws
can inherit traits their parents have acquired and shorter guts. To Nicholas Levis at the EVOLUTION may be a game of chance, but
during their lifetime. In 1807, French biologist University of North Carolina at Chapel Hill, some species load the dice. They modify
Jean-Baptiste Lamarck had argued that this is spadefoot toads provide a perfect example their environment and so may improve their
how novel traits evolve – the giraffe’s long of plasticity-led evolution. “It reorients how chances of survival. In doing so, they can
neck, for instance, arising as the result of we think about the adaptive process,” he says. change the course of their own evolution.
successive generations of animals reaching This process is called niche construction.
to higher branches for food. But according Such plastic changes occur because an
to Darwinian evolution, organisms must environmental trigger affects an organism’s Birds build nests, termites make mounds,
acquire a genetic mutation before they development in some way. Levis has found beavers create dams and countless other
can adapt to a new environment. To survive that in the spadefoot toads this happens via organisms engineer their environments.
on land, for example, fish first had to evolve 14 genes that underpin their ability to switch Traditionally, biologists thought of niche
the ability to get oxygen from the air. between the two different body types. Other construction purely as a consequence of
organisms may achieve a similar result via natural selection. However, that argument
Unsurprisingly, Weismann’s experiment epigenetic tags that turn genes on and off doesn’t always work. “It’s not the case that
failed: the offspring of his mutilated mice (see page 42). Research by Morgan Kelly genes for building concrete have spread
all had normal tails. But perhaps he was just at Louisiana State University suggests through human populations and that’s what
that eastern oysters in the Gulf of Mexico led us to build our urban environments,” says
The tadpoles of spadefoot have populations that can survive in low
toads can switch body type salinity waters because of epigenetic tags.
44 | New Scientist | 26 September 2020 If the environment remains unchanged –
abundant shrimps in the case of the tadpoles
and low salinity for the oysters – then
subsequent generations will continue to
exhibit the traits that help them survive. But
these traits are induced anew each time by
the environment, not directly inherited from
a parent, so how can they affect evolution?
“You can’t evolve if you’re dead,” says Kelly.
Plasticity may buy organisms valuable time
to adapt genetically. Here’s how it might
work. In an environment where survival
depends on a particular response, only
mutations that reinforce that response, or
at least don’t undermine it, will spread so that
eventually a plastic change becomes “fixed”.
We don’t know how prevalent this sort
of evolution is. However, one study found
that if you put fish on land they learn to
“walk”. Admittedly, the fish in question were
bichir fish, which can breathe air and haul
themselves along out of water if necessary.
Nevertheless, simply being on land
improved their walking abilities, hinting
that plasticity-led evolution might underpin
some key transitions in the development
of life on Earth, such as the evolution
of terrestrial animals. Carrie Arnold
8 The standard
model of evolution
CHANGE CAN BE QUICK
Twentieth century ideas about evolution
Contemporary evolution rest on three pillars: variation, inheritance
and selection. In this “modern synthesis”,
JOHN WEBSTER/GETTY IMAGES MANY people think evolution is which combines Darwinian theory with
something that takes millions of genetics, variation arises in the form of
years, making it imperceptible on human genetic mutations. DNA sequences
change at random as the result of external
timescales. They have it upside down, says forces, such as radiation, and internal
ones, such as damage to DNA or RNA
Michael Kinnison at the University of Maine. caused by highly reactive molecules called
free radicals. Most of these changes are
Kevin Laland at the University of St Andrews, He and others have shown that organisms can either neutral or detrimental to life, but a
UK. While niche construction isn’t always an few lead to the adaptations on which
outcome of evolution, it is often a cause. evolve extremely rapidly in response evolution is built.
Our own species provides a classic to changes in their environment. However, Mutations may occur in any cell, but
example. By inventing farming, humans not only those in germ cells, such as eggs and
only modified the landscape dramatically, evolution often reverses direction, making sperm, are passed down the generations
they also changed their diets. As time passed, to produce genetically distinct individuals:
human genetics began to change in response. it appear slow over long stretches of time. this is the basis of inheritance. One of
“There was selection on our digestive Charles Darwin’s greatest insights was
enzymes that allowed us to process The famous finches of the Galapagos the realisation that organisms tend to
carbohydrates and milk protein,” says Laland. produce a variety of offspring, not all
islands, which inspired Charles Darwin’s of which survive to reproduce. Natural
Niche construction isn’t a niche activity, selection weeds out those less well suited
says Laland. It happens across the tree of thinking about evolution, provide a prime to their environment, he said, while fitter
life – in animals, plants and even bacteria – individuals survive and pass their traits
and can have big impacts. With niche example of this. A single founder species on to their offspring. In this way, variation,
construction, organisms can ensure that the inheritance and selection result in
selective pressures acting on them are more reached the islands around 2 million years evolution, allowing life to adapt and new
consistent through time and space. By species to form as conditions change.
creating the conditions of their existence, ago and gave rise to at least 14 different
they are active players in their own evolution. Today, evolution remains one of the
species, some with large beaks for feeding most powerful ideas in science but,
Some believe this is overstating it. “Niche as with all good ideas, it is evolving.
construction plays little, if any, role in most on big seeds, and some with much smaller Many of the new conceptions arise
kinds of adaptation,” says Gregory Wray at from a better understanding of the
Duke University in North Carolina. But there beaks for other foods. That was considered mechanisms involved and a realisation
could be a way to settle the debate. If niche that organisms take active roles in their
construction is widespread and many species fast for evolution, but newer findings suggest own evolution. While accepting the
manipulate the selective pressures they underlying biological principles, many
experience, then evolution should lead to that these finches have been evolving far people see this model of evolution – the
broadly predictable changes. “A traditional so-called “extended synthesis” – as a
biologist will say you won’t be able to predict more rapidly than Darwin suspected. ragtag list of special examples. “The
general patterns in evolution – some of us movement has identified the problem, but
think we might be able to,” says Laland. In 1977, a drought on one of the islands, not the synthesis,” says Richard Watson
They plan to test the idea. “We’ll find out at the University of Southampton, UK.
who’s right,” he says. Colin Barras Daphne Major, wiped out ground finches.
But last year, Watson and his colleague
Only relatively large seeds were available Christoph Thies published a paper in
which they argue that the progress of
to eat, so birds with larger beaks did better, evolution on Earth – from the first
single-celled organisms to the complexity
and within a few generations, beak size of biological organisation we see today –
couldn’t have happened without the extra
had increased by around 4 per cent. Then mechanisms in the extended synthesis.
“In short, the extensions are the ‘glue’ that
the wet year of 1983 saw small seeds become make the whole more than the sum of the
parts,” they conclude. Kate Douglas
abundant again and, over a few years, beak
26 September 2020 | New Scientist | 45
size shrunk back. The finches had evolved
quickly but ended where they started.
Likewise, new species of finches may have
come and gone. In the 1980s, a male cactus
finch arrived on Daphne Major from an island
100 kilometres away and bred with two
female ground finches. The offspring were
fertile and bred only with each other in
subsequent generations. Such genetic >
isolation, which is the key to creating new returns it to the bag, before repeating the Gibbons’ long arms are a sign
species, was once believed to occur over process a further 39 times. These picks give a of how evolvable apes are
hundreds of generations, but here it second “generation” of tokens – and chances
happened in just three. Species formation are it contains more of one colour than the 10
can go rapidly backwards too. On the nearby other: 17 green and 23 yellow, for instance.
island of Santa Cruz, finches had split into Repeating the process with this new GENES DON’T JUST COME
large and small-beaked birds. But the population as a starting point will give a third FROM PARENTS
distinction between these species is starting “generation”, which may be even more
to erode. Now, most have medium-sized skewed in favour of yellow tokens. Eventually, Horizontal gene transfer
beaks, probably because people feed them the experimenter might randomly pick a
rice so they don’t need a specialised beak. generation containing all yellow tokens.
Thousands of examples of rapid evolution This monochromatic outcome is more
have been documented. For instance, in just likely in smaller populations: it would
half a century, killifish in the US evolved to take countless generations for 1000 green
cope with pollution many times higher than and 1000 yellow tokens to “drift” into a
the usual lethal dose. In fact, Kinnison avoids population of 2000 green tokens, for
the term rapid evolution because he thinks example, but perhaps just a few generations
this is the norm. Instead, he talks of for 10 green and 10 yellow tokens to become
“contemporary” evolution. Michael Le Page a population of 20 green tokens. Such
outcomes can and do occur in nature, which
9 shows how a population can lose genetic
variability simply through chance.
SURVIVAL OF THE… LUCKIEST
Biologists have known about genetic drift
Genetic drift for a century, but in recent years they realised
that it could be especially common in urban
THE Great Ziggurat of Ur – a massive step settings where roads and buildings tend to
pyramid – is one of the finest examples isolate organisms into small populations.
of 21st-century urban architecture. The 21st A 2016 study of the white-footed mouse,
century BC, that is. Large cities were still quite Peromyscus leucopus, in New York supported
a recent invention when it was built. Urban the idea. Jason Munshi-South at Fordham
landscapes are very new in the context of life University, New York, and his colleagues
on Earth. Yet many species now call them discovered that urban populations have lost
home – and their evolution may have had as much as half of their genetic diversity
more to do with luck than adaptation. compared with rural populations.
Natural selection favours certain genes – Last year, Lindsay Miles at the University
those that make an organism best adapted to of Toronto Mississauga, Canada, and her
a particular environment. But evolution can colleagues published a review of evidence
also occur through a non-adaptive process from about 160 studies of evolution in urban
called genetic drift, whereby a gene may environments, in organisms ranging from
become dominant in a population purely mammals and birds to insects and plants.
by chance. Genetic drift is often explained in Almost two-thirds of the studies reported
terms of a bag of tokens with equal numbers reduced genetic diversity compared with
of two colours – 20 green and 20 yellow, say. rural counterparts, leading the researchers to
A person draws a token, notes its colour and conclude that genetic drift must have played
a role. “Genetic drift can definitely be a
significant driver of evolution,” says Miles.
These findings have big implications,
because populations lose their ability to
adapt and thrive if they lack genetic diversity
for natural selection to work on. Of course,
genetic drift isn’t confined to urban settings,
but given how much urbanisation is
expected to grow, the extra threat it
poses to wildlife is concerning. It highlights
the need to create green corridors so that
animals and plants don’t become isolated
into ever-smaller populations. Colin Barras
46 | New Scientist | 26 September 2020
HEATHER ANGEL/NATUREPL.COM by viruses and even snatch free-floating DNA 11
from the environment. This process is called
CHRIS HITTINGER studies budding yeasts, horizontal gene transfer. As increasing SOME THINGS ARE BETTER
the group that includes Saccharomyces numbers of microbial genomes have been AT EVOLVING
cerevisiae, the yeast beloved of beer brewers sequenced, scientists have come to realise
and bread makers. It is one of the most that it is remarkably common. Microbes Evolvability
diverse groups of organisms with a nucleus aren’t passively waiting around to
(aka eukaryotes), so Hittinger is used to accumulate mutations to adapt to changing MONKEYS didn’t stand a chance. When
seeing bizarre things in his lab. A few years environments. Instead, they can pick up it came to walking on two legs, apes
ago, however, he saw something that really genes they encounter, giving natural were always going to win out. Our branch
surprised him. “There were a bunch of genes selection far more variety to work on. of the primate family tree had what it took
in some of these yeasts that simply should “They’re all sharing genes with each other, to evolve long legs, freeing up hands for
not have been there,” says Hittinger at the and it’s really a massive network of gene other functions such as making complex
University of Wisconsin-Madison. The genes transfer events,” says Gregory Fournier at tools – a significant adaptation on the road
were used by bacteria to make iron-grabbing the Massachusetts Institute of Technology. to becoming human. In this respect,
enzymes, and it looked like an ancestor of the monkeys just aren’t as evolvable as apes.
yeast had stolen them – as indeed it turned Horizontal gene transfer has been most
out they had. frequently documented in prokaryotes, Evolvability is a simple concept. “It’s the
single-celled microbes that lack a nucleus capacity of a population to evolve adaptively
For nearly a century, microbiologists have and so have few physical barriers to stop DNA and to generate phenotypic [observable]
known that bacteria can swap genes with from elsewhere being incorporated into variation that’s heritable,” says Tobias Uller at
each other, acquire viral genes when infected their genome. But Hittinger’s work shows Lund University in Sweden. Some organisms
that even some eukaryotes can borrow from are better at this than others, as the evolution
distantly related bacteria. “Yeast and bacteria of bipedal locomotion in primates illustrates.
have fundamentally different ways of turning Early primates – in common with many
DNA into protein, and this seemed like a animals – had four limbs that were
really, really strange phenomenon,” he says. approximately the same length and
performed a similar function. All monkeys
DNA jumble sale retain this anatomy. But at some point, apes
broke free of this constraint and became
Melanie Blokesch at the Swiss Federal more likely to generate front and rear limbs
Institute of Technology in Lausanne has of different lengths. The result is clear to see
shown that physical closeness and the in the range of ape body shapes today – from
amount of time two organisms spend next to long-armed gibbons to long-legged humans.
each other is key to their chances of acquiring
DNA. Other studies indicate that metabolic What isn’t so clear is exactly what it means
and functional genes, such as those that help for a group to be evolvable. Biologists have
an organism utilise a novel food source or been discussing evolvability for two decades,
detoxify a harmful chemical, are the most but there is still no agreement on exactly how
likely to end up at the ersatz DNA jumble sale. to use the term. Rachael Brown at the
The spread of antibiotic resistance genes in Australian National University, Canberra, has
bacteria shows just how important this identified five distinct definitions. She points
phenomenon is to the survival of microbes. out that a population might be considered
highly evolvable according to one, but not
What about the wider role of horizontal particularly evolvable according to another.
gene transfer in evolution? “The question is
how much [horizontally transferred DNA] As the climate becomes drier, for instance,
persists over long periods of time, and ends some plants grow smaller leaves that lose less
up being material that is inherited and water through evaporation. In doing so, >
passed down to future species,” says Fournier.
There are hints that it could be quite a lot.
Hittinger isn’t alone in finding out-of-place
clumps of DNA. Others have discovered
them in mammals, and analysis of the
entire human genome revealed that at least
8 per cent of our DNA derives from viruses.
Indeed, by one estimate up to half of all
human DNA derives originally from
horizontal gene transfer. Carrie Arnold
26 September 2020 | New Scientist | 47
they arguably demonstrate a form of CARLOS VILLOCH, MAGICSEA.COM/ALAMY 12 fascinating quirk of evolution called parallel
evolvability, says Uller. The plants haven’t radiation: the phenomenon in which a
changed genetically, but they have found a way EVOLUTION FAVOURS species in one location diversifies into several
to survive in the short term, buying some time CERTAIN OUTCOMES distinct forms and, independently, the same
during which they might accumulate genetic diversification occurs in a different location.
mutations and so evolve for a more arid life. Developmental bias A famous example is cichlid fishes living in
Lake Malawi and Lake Tanganyika in Africa.
Other biologists argue that this isn’t AT THE heart of evolution is a random Each lake contains many different species
evolvability at all. Rachel Wright at Smith process: mutations to DNA that result in that show striking similarities in the variety
College, Massachusetts, is one of them. genetic variation. Yet, observe what evolves of body shapes to species in the other lake,
She and her colleagues recently published and you find that some outcomes are more despite being more closely related to those
research on the evolvability of reef-building likely than others. Instead of appearing living in their own lake. These body shapes
corals in the face of three environmental directionless, as you might expect with a adapt species to particular niches or diets,
challenges: rising sea temperature, ocean truly random process, evolution is full of so must have evolved by natural selection.
acidification and increase in infectious repeating patterns. Now we know why. But the forms the fish take aren’t necessarily
diseases. They found that the corals with a “You find some solutions evolving over the only possible adaptive solutions.
tolerance for one of these stressors were also and over again, not because they’re the This suggests there are features of cichlid
able to cope well with the others. This, they best, but because the developmental development that make some body types
say, shows that these corals have the potential system [of organisms] has the tendency more likely to arise.
for rapid adaptation under climate change. to throw up certain variations,” says
“If the responses we observed were due to Tobias Uller at Lund University in Sweden. Despite directing evolution down certain
completely non-genetic effects, I would not tracks, developmental bias isn’t inherently
consider this evolvability,” says Wright. This is called developmental bias, and limiting, says Uller, because it can promote
it can be seen clearly in domestic animals. variation that is more likely to be beneficial
The concept of evolvability is flawed but Many of them have floppy ears and curly tails and therefore more likely to survive. It could
Brown says biologists need to agree a proper along with shorter snouts and different coat help explain why cichlids are so diverse and
definition if they are to use it effectively. That colours compared with their wild ancestors. similar bursts of evolution among all sorts
is important because evolvability goes to the Yet, these characteristics have no obvious of organisms, from the Galapagos finches
heart of some big evolutionary questions, links to the qualities for which these studied by Charles Darwin to Australian
from the potential effects of global warming creatures have been bred, such as tameness, marsupials. Carrie Arnold
to the evolution of bipedalism. Colin Barras milk production and meat yield. The mystery
of so-called domestication syndrome was 13
Some corals can rapidly adapt cracked when scientists homed in on a tiny
to stressful conditions cluster of stem cells in the developing WE CAN STOP EVOLUTION
embryo. These “neural crest cells” are
involved in the development of a variety of Anti-evolution
tissues influencing things like face and ear
shape and coat colour. They also give rise to EVOLUTION didn’t just happen in the past.
the adrenal glands, which play a key role It is happening right now, and it is often
generating the fight-or-flight response that seriously bad for us. That is why researchers
underpins tameness. Increase tameness by are exploring ways to slow, stop or even
breeding for it, and the shorter snout and reverse unwanted evolution, or out-evolve it.
curly tail are dragged along for the ride.
Perhaps the biggest threat posed to us by
If certain characteristics can develop evolution is the rise of antibiotic-resistant
more easily than others, than we should superbugs, which already kill 35,000 people
expect to see recurring patterns in nature. each year in the US alone. Evolution also
Developmental bias could be behind a
48 | New Scientist | 26 September 2020
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