The Mantis Shrimp
The mantis shrimp is one of the
most interesting crustaceans out
there in the ocean, although they
are midway between families being
neither mantises nor shrimps, the
mantis shrimp is highly known for
being a fighter, precisely a boxer,
and even better, the best one out
there, the mantis shrimp especially
“the smasher” type, is known
for having the fastest strongest
fist out there in the water, with
an acceleration 10,000 times
the gravity, the smasher mantis
shrimp gives out a blow after blow
beating its prey to death in a tiny
fraction of time, and to be exact,
this smasher can strike its prey
with a power of 1500 newtons of
force in less than three thousands
of a second which means it takes
down its lunch about a thousand
times faster than you blink.
And despite the long talk we can
have about the mantis shrimp
being the next “Muhammed Ali”
of the underwater, we are going to
skip it and have another one about
its huge “Satellite” eyes which is
what we are here for. The mantis
shrimp has this really huge alien-
like eyes, that are much harder
to understand than our simple
human eyes. Quickly going through
its eyes’ anatomy; the mantis
shrimp has two very large eyes,
each has its own mobile stalk so
they both move freely in different
directions giving it a huge field of
vision. They both have “trinocular
vision” which means they can
overcome the depth and distance
16
on their own by focusing on objects.
The mantis shrimp’s eye
consists of two hemispheres
separated by “the midband”,
this midband is made up of six
rows of specialised clusters of
photoreceptors, pigmented cells
and supporting cells, these layers
are called “the ommatidia”. Inside
this midband, this is where all the
magic happens, the six rows forming
the midband are divided according
to function, so the first four rows are
dedicated to normal human visible
light along with UV light, and in
each row it has a different receptor
for the UV giving it an extremely
accurate vision, while as for the
last two rows, they have those tiny
hairs that are precisely positioned
for their job which is detection
of polarised light; this gives the
mantis an ability to see visible
light, UV light and also polarised
light but in fact it doesn’t just have
the ability to see polarised light —
like that reflected from water for
example— but it’s the only creature
out there that has the ability to see
circularly polarised light which is
very impressive for this little fighter.
But what about the cones in its
eyes and its color distinguishing
abilities? While we humans have
three different cones and while
most birds have 4 or maximum 5
cones, this guy here has 12 different
types of cones, which makes your
head spin around thinking about
all of the huge color possibilities
in front of its weird eyes, you would
be pretty sure it can discriminate
between any shade out there a
million times better than humans
or birds or actually any creature
out there, but surprisingly, that’s
not true, with a few experiments
done the mantis shrimp turned out
to be the worst in discriminating
between colors and shades so what
are we missing? Scientists so far
don’t have a clear answer except
for this hypothesis that the mantis
shrimp despite being the strongest
is not actually the smartest.
Being able to discriminate between
colors and shades requires that
we combine efforts between all
three types of cones and our brain,
translating the signals each one of
the three received and combing all of
them together to get the final shade
ready for our eyes to recognise, but
this is not the case with the mantis,
it actually recognizes each color
on its own which means when its
cones are stimulated it translates
each message coming from each
cone directly into a color without
combining the messages coming
from all 12, it’s like sitting in a room
with a million different color bombs
being thrown in your face, ofcourse
you won’t be able to recognize a thing.
As fascinating as those eyes
are, they don’t view this world
as beautiful as they could’ve
unfortunately, but at least they are
fighting champions of the ocean
and with those beautiful colors on
their bodies and eyes they can win
any seaworld beauty crown they
want if they just put their minds to it.
The Recap Magazine
July 2018 Issue
17