6 March 2021 | New Scientist | 23PsychologyTechnology DomesticationMoth mates more
often in red lightThe yellow peach moth is
more sexually active when
bathed in red light than it
is in light of another colour.
The discovery came during
lab experiments, and may
be because red light has a
long wavelength that can
pass through animal tissue
and stimulate cellular
activity (Frontiers in
Genetics, doi.org/fxdg).Fossil suggests Asia
was a dino hubA Diplodocus-like dinosaur
has been discovered in
Uzbekistan – the first of
its kind found in central
Asia. When Dzharatitanis
was alive about 90 million
years ago, Asia might have
been a geographical hub
from which similar
dinosaurs could have
spread to other regions
(PLoS One, doi.org/fxdt).2.3-litre plastic
bottles are greenestWe could reduce plastic
waste by buying bottled
products that are 2.3 litres
in volume, because these
provide the greatest
capacity relative to the
amount of plastic used.
A 20 per cent shift towards
bottles of this size could
reduce annual US waste
by 9000 tonnes (Scientific
Reports, doi.org/fxdw).It is trick y to know
when to stop talkingCONVERSATIONS often go on
longer than we would like because
people mask how they really feel.
That is the finding of Adam
Mastroianni at Harvard University
and his colleagues. They surveyed
more than 800 people who were
randomly recruited. Participants
responded to questions about
recent conversations with a friend
or family member, including how
they felt about the conversation’s
length and how it ended.A FIBRE-OPTIC cable at the bottom
of the Pacific Ocean can be used to
detect earthquakes and waves.
Zhongwen Zhan at the
California Institute of Technology
and his team, including researchers
at Google, which owns the cable,
used traffic data from the
10,000-kilometre-long link
to measure changes in pressure
and strain in the cable. Using the
data, they could detect deep-sea
earthquakes and ocean waves
called swells generated by storms.
Over a nine-month period, the
team recorded about 30 ocean
storm swell events and around
20 earthquakes over magnitude 5,strong enough to damage buildings,
including the magnitude-7.4 quake
near Oaxaca, Mexico, in 2020. The
team had wanted to measure a
tsunami, but none occurred during
the study (Science, doi.org/fxcw).
Deploying and maintaining
geophysical instruments on the
sea floor is difficult and expensive,
so underwater seismic stations are
relatively rare. There have been
efforts to use fibre-optic cables as
seismic sensors, but these required
specialised laser-detection kit at
both ends of the cable or the use of
dedicated fibres within the cables.
Zhan says the new approach gets
round these issues. PPThe team also recruited
more than 250 students and non-
students pooled from volunteers
available for studies at Harvard’s
psychology department. This
group took part in one-on-one
conversations with another of
the volunteers, who they didn’t
already know, in the laboratory.
Mastroianni’s team recorded
each conversation and asked the
volunteers to talk about anything
they liked for at least a minute.
When the conversation had ended,
both participants could leave the
room. They were separately
quizzed about their talk. If theHow pets conquered
the Americas with usWE MAY have the best evidence
yet that the first people in America
took their dogs along for the ride.
Charlotte Lindqvist and her
team at the University at Buffalo
in New York extracted DNA from
the oldest known dog remains
found in the Americas. They found
the genetic signature is consistent
with the idea that domesticated
dogs arrived between 17,000 and
16,000 years ago – roughly in line
with the currently accepted time
for the arrival of the first people.
The bone, found in the late
1990s in Lawyer’s cave, Alaska,
had already been dated to a little
more than 10,000 years ago, but
was assumed to have come from a
bear. Only when the team studied
DNA from it did they realise it
belonged to a dog, making it the
earliest evidence of dogs found
so far in the Americas.
The team used mitochondrial
DNA from the bone to understand
the dog’s genetic history. This
showed that it was closely related
to the lineage of domestic dogs
in the Americas before European
contact and colonisation. It also
showed that the dog’s lineage
branched off from dogs living in
Siberia roughly 16,700 years ago
(Proceedings of the Royal Society B,
doi.org/fxc3). Karina Shahchat lasted 45 minutes, someone
stepped into the room to end it.
Conversations rarely ended
when people wanted them to. On
average, the length of a chat was
off by about 50 per cent compared
with how long people would have
liked them to last, but there was a
lack of communication between
participants about this (PNAS,
DOI: 10.1073/pnas.2011809118).
People in conversations not
only want different endpoints, but
also know “precious little” about
what their conversational partners
really want, says Mastroianni.
Christa Lesté-LasserreHow do you detect a deep-sea
earthquake? Just ask Google
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