Page 15 - Annonce Dergi | İzmir Özel Saint-Joseph Fransız Lisesi

Is It Possible

to Learn their visual processing and integration centers. This phenomenon is

without a Brain? called associative learning through rhopalial nervous systems (RNSs).

“If you want to understand complex structures, it’s always good to
start as simple as you can”, “Looking at these relatively simple nervous
In today’s scientific world the general understanding of learning and systems in jellyfish, we have a much higher chance of understanding
memory is that the more developed the nervous system, the more all the details and how it comes together to perform behaviors.” says
advanced the learning capacity will be. senior author Anders Garm of the University of Copenhagen, Denmark.

Until very recently, it was thought that learning and memory skills This new discovery reveals how little we actually know about
could not be achieved without the central brain. However, due to neurological systems, and researches like this broaden our horizons in
the researches conducted by examining a certain type of jellyfish, it the field of neuroscience.
was discovered that these creatures, which do not have a centralized
brain and only have about one thousand nerve cells, can learn to Damla Töre
avoid different obstacles over time. Scientist from the University of
Copenhagen have demonstrated that the jellies show the ability of
changing their behavior based on previous experiences, which is a
sign of a learning capacity at a much complex level.

It’s known that jellyfish existed on Earth more than 500 million years
ago, long before the age of dinosaurs. They do not have a heart or a
brain and are made up of around 98% water. They are also invertebrates.
As for the of the type of jellyfish which was used in the experiment
Tripedalia cystophora commonly known as Caribbean box jellyfish
is a bit more unusual than what one would expect. These creatures,
which are not much bigger than a fingernail consist of a boxy dome-
shaped bell and three tentacles on each of the four corners of the bell.
They are also equipped with a very advanced visual sensory system,
which comprised of 4 rhopalias, cylindrical structures containing light-
sensitive cells that helps them navigate their way through mangrove
roots and hunt copepods.

How Was the Experiment Done?

A group of scientists led by Anders Garm who is an associate professor
of marine biology at the University of Copenhagen, created an
experiment environment in a round tank with grey and white stripes to
replicate the mangrove root conditions, jellyfish’ natural habitat. Then,
they varied the contrast settings and looked for alterations in jellyfish
behavior. As a result, scientists noticed that after a few collisions,
jellyfish learned to predict the distances of the obstacles and how to
avoid them. This shows that T. Cystophora is capable of learning by
visual and mechanical stimuli through their rhopalias which act as

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