way, says Wild. “She’s probably
dropping her own eggs into the
brood pile, where the host workers
are treating them as their own.
She’s a parasite on the food and12 | New Scientist | 21/28 December 2019
EntomologyTechnologyClare WilsonAlice KleinWHAT should we call Texan ants
that ride on the backs of other ants?
Rodeo ants, says Alex Wild at the
University of Texas at Austin, a
discoverer of two new species
of such insects.
While little is known about
them – so far, Wild’s team has found
just one individual from each of the
two species – a few other kinds of
ant elsewhere in the world are also
known to perch on the backs ofRodeo ants that ride
on the backs of other
ants found in TexasOLDER people in Japan are
strapping on exoskeletons to
help meet the physical demands
of their jobs and remain in the
workforce for longer.
Japan’s population is rapidly
ageing, with a record 28 per cent
of its people aged 65 or older. This
has led to a shortage of workers,
particularly in manual labour
industries such as construction,
manufacturing and farming.
To encourage older people
to work on, tech companies in
Japan have developed exoskeleton
suits that make it easier to lift and
carry heavy objects. “We have no
option, elderly people need to
stay in the workplace,” says Daigo
Orihara at Innophys, which makes
a model called the Every Muscle
Suit (pictured).
The suit, which is worn like a
backpack, doesn’t contain any
batteries or motors and weighs
less than 4 kilograms. When
users put it on, they squeeze a
hand pump 30 times to fill the
suit’s “artificial muscles” with
pressurised air. Once pumped up,
the artificial muscles exert a force
that allows people to lift up to25 kg fairly easily, says Orihara.
They need to be reinflated every
day or two, he says.
Innophys has sold 4000 of
the suits – which cost about
£1000 – since releasing them in
April 2018. They are currently
being used by one of Japan’s
biggest whisky companies to help
workers lift barrels, by nursing
homes to help staff lift residentsin and out of bed, as well as by food
manufacturers and construction
companies. Older people have told
the company that the suits have
allowed them to stay in manual
jobs for longer, says Orihara.
“One client is a family-owned
company which makes and sells
pickled radish and uses heavy
weights in the process of
production,” he says. “The father
is in his 70s and was supposed to
retire, but is still working with
our muscle suit,” says Orihara.Panasonic is also developing
a range of exoskeleton suits. Its
leading version – the Atoun
Model Y – went on sale in July 2018
at a cost of £4200 and is powered
by motors instead of pressurisedair. It has a battery life of 8 hours,
weighs 4.5 kg and generates an
assistive force of 10 kg.
Similarly, Japanese company
JTEKT, which is part of the Toyota
group, began selling a motorised
exoskeleton for lifting heavy
objects in August 2018. It says
it, too, is designed to support
the ageing workforce.
The demand for exoskeletons
is likely to increase as Japan is
forced to raise the retirement
age to address worker shortages,
a move being considered by the
nation’s prime minister Shinzo
Abe. “I want healthy, willing
elderly people to use their
experience and wisdom in society,”
he said earlier this year. ❚Exoskeletons are letting Japan’s
ageing population keep working
Rodeo ants may fool larger queens’
workers into looking after their eggsCOURTE
SY
OFDAIGOORIHARANews
Workers wearing exoskeletons
on a golf driving rangeAL
EX
W
ILD25
Number of kilograms the Every
Muscle Suit allows people to liftother ants. In those cases,
the “riders” have evolved
an unusual way of life.
Most ants live in big colonies,
sometimes comprising millions
of ants, with one egg-laying queen
and multitudes of sterile workers
that bring food home to the nest
and tend to the eggs.
The riders don’t have any
workers: they are females that cling
to the back of a queen from a bigger
species. The riders lay their own
eggs and fool the larger queens’
workers into looking after them.
The two newly discovered Texan
species are likely to act in the samelabour of the host colony.”
They seem to have adapted their
appearance and behaviour to their
freeloading lifestyle. Each has about
the same density of hairs on its back
as its host ant does, as if to blend in.
Although one of the ants was
killed on collection, Wild observed
the second in the lab for some time.
When he repeatedly detached it
from the larger ant, it kept climbing
back on again. “They really like
being on the queen,” he says.
Wild presented the findings at
the Entomology 2019 conference
in St Louis, Missouri. ❚