Newsademic British English edition 260



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12th November 2015 
N e w s a d e m ic .co m ™
 - British English edition 
page 
15
Some waved large Romanian flags 
with holes in them. These became a 
symbol o f the 1989 protests, which 
led to Ceausescu’s downfall. Then, 
bullets made the holes.
M r Iohannis spoke with the pro­
testers. He said that the country’s 
elected politicians could not ignore 
what was happening. After M r Pon- 
ta resigned, the president said he 
would appoint an interim, or tem ­
porary, prime minister. Elections for 
new political leaders will then be 
organised. □
S
w im m in g
 
s t u d y
Jellyfish and lampreys live in the 
sea. Lampreys are eel-like creatures. 
These two marine creatures look 
very different. Yet they are both ex­
cellent swimmers. Researchers in the 
USA have discovered that jellyfish 
and lampreys have an unusual way 
o f moving through the water. This is 
the first time that their unique swim­
ming methods have been recorded.
It’s known that jellyfish, or je l­
lies, have lived on the Earth for at 
least 500 million years. There are 
more than 1,000 jellyfish species. 
They are found in all the world’s 
oceans. Some live near the surface. 
Others prefer deeper waters. Jelly­
fish are not fish. All fish are verte­
brates, which means that they have 
a backbone. Jellyfish do not. A je l­
lyfish is over 90% water.
M ost jellyfish have an umbrella­
shaped body (known as a bell), and 
long tentacles. The bodies o f the 
smallest jellyfish are about one mil­
limetre (0.04 inches) across. The 
biggest ones can be two metres (6.6 
feet) wide. A jellyfish uses its tenta­
cles to catch its food. M ost jellies are 
harmless to humans, but a few are 
highly poisonous. The w orld’s most
deadly jellyfish is a type o f box jelly 
called 
Chironex fleckeri.
Usually 
called the sea wasp, it lives in seas 
between Vietnam, the Philippines 
and northern Australia. Lampreys 
are a type o f fish. Like eels, they 
have long bodies and no scales. The 
biggest ones are about one metre 
(3.3 feet) long. Lampreys do not 
have jaws. Some species suck other 
fishes’ blood. Others filter, or strain, 
food from the water. Lampreys live 
near coasts or in freshwater rivers.
Sea wasp (Avispa m arina)
Humans and most other land ani­
mals walk or run by pushing against 
the ground. Birds push or flap their 
wings against the air. Marine ani­
mals that swim use their fins, tails or 
tentacles to push against the water. 
This ‘pushing movement’ creates an 
area o f high pressure between the 
animal and the ground, air or sea. 
There is an immediate forward (or 
backward) movement. Yet this does 
not last for long. Therefore the ani­
mal has to keep ‘pushing’.
The American researchers sus­
pected that jellyfish and lampreys 
swim in a different way. They de­
cided to investigate. The research­
ers fitted lasers and cameras around 
a large water tank. They then tipped 
millions o f tiny, silver-coated glass
beads into the water. These beads are 
only ten micrometres (one millionth 
o f a metre) across. As the jellyfish 
and lampreys swam in the tank, the 
beads highlighted how the water 
moved around them. The lasers and 
cameras recorded this movement.
The beads showed that jellyfish 
and lampreys don’t push against the 
water. Instead, the way in which 
they bend their bodies creates ar­
eas o f low pressure. The surround­
ing water then flows, or moves, 
into these areas. This water motion 
moves the jellyfish and lampreys 
forward. So instead o f ‘pushing’ 
through the water, jellyfish and 
lampreys are ‘pulled’ or ‘sucked’ 
through it. The researchers worked 
out that this way o f swimming uses 
far less energy. This probably ex­
plains why jellyfish and lampreys 
are such good swimmers.
Marine engineers are expected 
to be interested in the research­
ers’ work. It may be possible to 
design underwater robots to swim 
in a similar way. If so, the robots 
could move through the water very 
quickly but use less power. Copying 
designs found in the natural world 
like this is known as ‘biomimicry’ 
or ‘bioinspiration’. □
R

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