“dinosaurs were remarkably climate-
tolerant, thriving from equatorial to polar
latitudes”, write the authors of a paper in the
journalScientific Reports.
The NSW fossils, from the outback
town of Lightning Ridge, were so small they
may have belonged to embryonic dinosaursthat weighed around 150 grams and were
less than 20 centimetres in length from
head to tail.
“They were just about at, or prior to,
the point of hatching from the egg,” says co-
author Phil Bell, from the University of New
England. – JOHN PICKRELLInanimate material can be “trained”
to behave like small artificial muscles,
a new study suggests.
Picture a robot and images of futuristic
humanoids of metal and code come to
mind. However, researchers in Finland are
creating a tunable “micro-robot” that could
become an important asset for biomedical
procedures.
It’s made from liquid crystal polymer
networks (the base for most plastics) layered
with a coat of dye that responds to heat. It
converts energy into a bending motion,
much like a human finger curls, thereby
“walking” at roughly the speed of a snail.
The method, published in the journal
Matter, represents the first time an
inanimate material has “learnt” an action.
Researchers used conditioning with heat
and its association with light to produce a
response – something like training a pet.
“Our research is essentially asking
the question if an inanimate material can
somehow learn in a very simplistic sense,”
says senior author Arri Priimägi, from
Tampere University of Applied Sciences.
Learning can be considered a sequence
of processes through which a biological
system or organism modifies its behaviour
based upon past experiences.
The full complexity of learning is
unknown, and involves perception,
memory, motor functions, consciousness,
and reward-seeking, many of which have
been connected solely to living organisms.
However, simple organisms learn
by fundamental learning forms such as
habituation, sensitisation and classical
conditioning.
In the micro-robot, classical
conditioning was used to prompt a response- bending – to an initially neutral stimulus:
light.
“My colleague, Professor Olli Ikkala
from Aalto University, posed the question:
TECHNOLOGY
Pavlov’s plastic ‘Can materials learn, and what does it mean
if materials would learn?’” says Priimägi.
“We then joined forces in this research
to make robots that would somehow learn
new tricks.”
The conditioning process to associate
light with heat includes turning the material
blue as the dye on the surface diffuses
throughout it. This increases the overall light
absorption, which boosts the photothermal
effect (an increase in energy in atoms caused
by the absorption of a particle of light) and
raises the micro-robot’s temperature.
It then “learns” to bend when exposed to
light as it self-heats.
Besides walking, the material can
recognise and respond to different light
wavelengths that correspond to the coating
of its dye. This characteristic makes the
material a tunable soft micro-robot that can
be remotely controlled – an ideal material
for biomedical applications.
“I think there’s a lot of cool aspects
there,” says Priimägi. – IAN CONNELLAN
Tiny fossils are
first known baby
dinosaurs from
Australia
Discovery reveals dinosaurs were
breeding near the South Pole.
A collection of tiny fossilised thigh bones,
some just 2.5 centimetres in length, are the
first remains of baby dinosaurs ever found
in Australia.
Discovered in NSW and Victoria, the
bones belonged to baby herbivores that
were small enough to sit in the palm of a
hand.
As Australia was much further south
100 million years ago – when these babies
were tottering around in their nests – they
are also proof that dinosaurs were breeding
in southern polar environments within the
Antarctic Circle.
The discovery adds to evidence that
PALAEONTOLOGY
JAMES KUETHERDIGEST
22 – COSMOS Issue 86