New Scientist - USA (2021-07-17)

17 July 2021 | New Scientist | 21

Solar system

Infectious diseases Animal behaviour

Cauliflowers’ fractal

florets explained

The Romanesco cauliflower

owes its unique shape to

the fact that it forms from

failed flowers. Each

nascent flower tries to

grow, but instead forms

shoots, the ends of which

also try to become flowers,

but instead form shoots,

and so on – ultimately

forming a fractal pattern

(Science, doi.org/gmxb).

Sea otters don’t

shiver in the cold

How sea otters stay warm

without insulating blubber

has been a mystery. We

now know they do so

using muscle tissue that

generates heat chemically

from energy in food –

which means sea otters

don’t have to shiver. The

mechanism is unique for

an animal as large as this

(Science, doi.org/gmxc).

Beetle lubricant

better than Teflon

A lubricant harvested from

the legs of a darkling beetle

(Zophobas morio) reduces

the friction between two

surfaces even more than

Teflon does. The wax-like

substance could be useful

in robots, if a way can be

found to make it in bulk

artificially (Proceedings

of the Royal Society B,

doi.org/gmxd).

Mystery of giant

planet’s rays solved

JUPITER regularly blasts out

powerful flares of X-rays as part of

its auroras, but how it does so has

been a mystery since these bursts

were discovered four decades ago.

Now, we have finally figured it out.

To solve the puzzle, William

Dunn at University College

London and his colleagues used

data from the European Space

Agency’s XMM-Newton space

telescope on Jupiter’s X-rays

and from NASA’s Juno orbiter

BATS, primates and other

mammals sold in the wildlife trade

host three-quarters of infectious

diseases capable of spilling over

from animals to humans. Just a

quarter of the traded species can

carry such zoonotic viruses.

Conservationists say the findings,

part of a first detailed, global look

at pathogens in traded mammals,

highlight ways to target high-risk

species to reduce the chance of

future pandemics. The World Health

Organization considers a wildlife

market in Huanan, China, to be

a possible origin of covid-19.

Most previous research in this

area has assessed disease risk

by looking at the frequency with

which animals are traded. Instead, a

US-India team took an existing data

set on mammals that are reservoirs

for known zoonotic viruses,

supplemented it with scientific

literature and then married it with

a database on whether animals

are in the wildlife trade or not.

The researchers found that

26.5 per cent of traded mammals

carry 75 per cent of known zoonotic

viruses. The biggest disease risk

among traded species was from

primates, bats, carnivores and

hoofed animals known as ungulates

(Current Biology, doi.org/gmrs).

Adam Vaughan

on the planet’s magnetic fields.

They found that the X-rays

occurred like clockwork once

every 27 minutes, and they

observed the exact same timing

in vibrations along the planet’s

magnetic field (Science Advances,

doi.org/gncb).

“You can picture the magnetic

field of a planet kind of like strings

on a musical instrument, and the

field can vibrate like the strings

on an electric guitar,” says Dunn.

Those vibrations are made up

of waves in the magnetic field.

Charged particles get caught up

in those waves, and then smash

Female vampire bats

like to care and share

VAMPIRE bats live in female-

dominated groups, and they

appear to groom and share food

with each other equally without

regard for social status.

Unlike the “strict, obvious

female dominance hierarchy”

seen in many other social animals,

the “egalitarian” social life of

vampire bats suggests individuals

do well when their group mates

are doing well, says Gerald Carter

at The Ohio State University.

He and his team decided to

observe 24 wild-captured, adult,

female common vampire bats

(Desmodus rotundus) and their

offspring in a large pen. From this,

the researchers concluded that the

bats have what they call a “weak

and shallow” hierarchy.

They also looked at social

hierarchies in 82 other species,

including mammals, insects and

birds, and found that the vampire

bats’ hierarchy was so weak that

it was less clearly defined than for

90 per cent of these other species

(Royal Society Open Science,

doi.org/gms3).

Unlike those species, the

female bats didn’t use grooming as

a tool to appease individuals of a

higher social rank, but instead they

groomed and shared food evenly.

Christa Lesté-Lasserre

into Jupiter’s atmosphere, causing

the X-ray pulses that we see.

Knowing this is important

because it hints that the same sort

of magnetic field vibrations may

be crucial to some of the highest-

energy processes in the universe.

“X-rays are typically used

to study really exotic, super-

energetic things like black holes,

things that are on the edge of the

human imagination,” says Dunn.

“The only way we can really

understand how those places

generate these X-rays is to go to

more nearby places that do it,

like Jupiter.” LC

Zoonotic viruses found

in the wild animal trade

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Really brief

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