the club is a very interesting
crustacean normally found around
coastlines and beaches but do you know
why some clubs use sea anemones as
pom-poms and did you know that some
crabs live in a certain animal tapu find
out more and the science of craps crops
are crustaceans defined by their thick
exoskeleton or shell they have ten legs
which makes them decker pods sidenote
the prefix deca having originated from
greek refers to the number ten for
example a decathlon would have ten
events and a decade has ten years anyway
the legs are divided into five sets and
the front two are adapted as pincers the
crab shell is armored which provides
protection for the soft tissue
underneath it the hard upper shell is
called a carapace which is the same type
of shell as a tortoise has you can
distinguish a male and female crab by
looking at their abdomens males
generally have a narrow and triangle
abdomen whereas females have a larger
round of one female crabs also usually
have smaller claws crabs use their claws
as a vice for crushing or cutting
objects a crack may also use a claw in a
fight but this is okay because it has
the ability to grow a new one
perhaps eyes are on stalks which can
move in all directions and even retract
when needed the stops can help them see
when they are hiding below water around
rocks or in sand most crabs breathe with
gills like fish these gills extract the
oxygen that dissolves in water as water
flows over them but they can still
absorb oxygen on land as long as the
gills are kept moist which might be
where you see them blowing bubbles on
land sometimes there are also crabs with
lungs as well as gills and this enables
them to live on land in places like the
jungle crabs typically walk sideways
this is because there
are located on the sides of their bodies
and their joints point upwards so
sideways movement is quicker and more
efficient the smallest crab in the world
is the pea crab this is less than a
third of an inch or the size of a pea
they are parasitic and live in mollusks
like oysters that provide oxygen and
food in the form of zooplankton the
biggest crab in the world is the
Japanese spider crab which lives deep in
the ocean floor and is believed to have
a leg span of up to 12 feet that is over
twice the length of the average human
adult lying horizontally did you know
the remote Christmas island in the
Indian Ocean is home to the Christmas
Island red crab these crabs are drawn by
the moon to make a yearly migration from
the forest to the beach to breed what is
special about this is that around 40
million crabs make this journey that's
more crabs than there are people in
Canada the boxer crab is also known as
the pom-pom crab because it will see
anemones on each of their claws like an
angry cheerleader they use the sea
anemones to fight against other crabs or
predators as an enemy sting with venom
filled tentacles in turn the sea
anemones get fed by leftover scraps of
food from the crab the poo dwelling crab
we mentioned earlier lives in a giant
cave in Borneo called deer cave it lives
in a giant hundred metre mound of guano
formed with the droppings of the
millions of bats who also lived there
thank you for watching the science of
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