[Music]
jellyfish can be found all over the
world from deep oceans to shallow
coastal areas
they’ve been around for hundreds of
millions of years
boneless brainless and bloodless
jellyfish are some of the most diverse
and fascinating creatures in the sea
What is a jellyfish
jellyfish aren’t actually fish
with thousands of different species in
two different biological phyla jellyfish
is more of a broad term than anything
else
unlike fish which have backbones
jellyfish are invertebrates
jellyfish got their common name from the
jelly-like material they’re made out of
called mesoglia
in recent years scientists have started
using the umbrella term sea jellies to
clear up the confusion
Immortal jellyfish
there is an immortal jellyfish
jellyfish can reproduce sexually by
releasing sperm and eggs into the water
and reproduce asexually by splitting
into two or cloning
but at least one jellyfish can actually
reverse the aging process
the turatopsis dorniere has earned the
moniker the immortal jellyfish for being
able to undergo a process called
transdifferentiation
an adult or juvenile under stress
instead of dying can revert back to a
polyp and begin the life cycle all over
again
it is the only animal in the world that
is known to be able to reverse its life
cycle
Box jellyfish
box jellyfish are the most venomous
marine animals in the world
jellyfish stings are a common fear of
beachgoers worldwide and with good
reason
there are an estimated 150 million
jellyfish stings reported annually
and while not all jellyfish have
stingers the australian box jellyfish or
chiron x fleckery is considered the most
venomous marine animal in the world
its deadly tentacles can grow up to 10
feet long
humans and other animals that are
unlucky enough to get stung may
experience paralysis cardiac arrest and
even death within just a few minutes
jellyfish are 95
water
to put this in perspective the average
adult human male is about 60 percent
water but jellyfish are much simpler
than humans they don’t have hearts blood
brains or bones
jellyfish do have very basic sensory
organs in their bells and tentacles and
a simple digestive cavity which serves
as a stomach intestine and esophagus
if a jellyfish washes up on the beach it
will mostly evaporate due to the high
water content
Jellyfish blooms
groups of jellyfish are called blooms
swarms or smacks
jellyfish blooms can form quickly and
scientists think that the jellies
congregate for mating purposes
in extreme cases the bloom can be so
dense there are more jellyfish than
water in a given area
they can be as small as a cubic meter or
cover hundreds of square miles
while these blooms are natural they’ve
caused problems all over the world such
as clogging fishing equipment in mexico
destroying chinese ships and closing
beaches in australia and europe
there is still so much to learn about
these floating mysterious creatures
scientists believe that there may be as
many as 300 000 species of jellyfish
that we haven’t yet discovered
[Music]
[Music]
