NARRATOR: The green anaconda,
known as the heaviest
snake in the world.
They reach up to 25
feet long, and can
weigh more than 300 pounds.
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To support its bulk, anacondas
spend almost all of their time
in and around water.
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Camouflaged to blend
into plant choked water,
this snake usually waits
for prey to come to it.
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Eyes and nostrils positioned
on top of their heads
allow the snakes to remain
almost completely submerged
as they wait to ambush.
The anaconda shares
this flooded plane
with the capybara, the
largest rodents on earth,
often reaching more
than 100 pounds.
Capybara are social
animals and herbivores.
Much of their diet
consists of aquatic plants,
so they spend a lot of time
near water, prime hunting
ground for the anaconda.
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Underwater, it can stalk
without being seen,
poking its head up just long
enough to gauge the distance.
Then, it waits.
It strikes, latching on
with six rows of teeth,
coiling itself around
the large rodent.
There is no escape.
Anacondas don't kill with venom.
They are constrictors.
They compress the blood
flow to their prey's heart,
causing cardiac arrest.
Once the heart has
stopped beating,
they begin to eat their
meal whole, toes and all.
They do this with the help
of both stretchy ligaments
and mobile joints
in their mouths.
In the middle of the
anaconda's upper jaw
are two rows of
backward pointing teeth.
These teeth can move
independently, biting into prey
and helping move the snake's
head up and over its meal.
But eating this way
creates a problem.
With its mouth
stretched so tightly,
breathing could be a challenge.
Evolution developed
a solution for that.
The windpipe gets pushed forward
from deep within the throat.
It becomes like a
snorkel, effortlessly
breathing while feeding.
It's a huge meal.
The anaconda will rest,
digesting its catch for weeks.
A capybara this size will
satisfy it for months,
but eventually, it will
need to feed again.
