WEBVTT

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Welcome to Spotlight Advanced. I'm Megan
Nolette and I'm Bruce gulland Spotlight uses a

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special English method of broadcasting. It
is easier for people to understand no matter

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where in the world they live.
The night breeze cools the shore of the

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ocean. Waves crash against the rocks. A full moon is in the sky,

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its light shines off the water.
You notice a strange looking animal coming

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out of the water. From far
away. It looks just like one of

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the rocks, but as it gets
closer you notice its long tail and nine

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eyes. This is a horse crab. It has come up from the water

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to bury its eggs in the sand. Many people may never see this strange

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creature, but this horseshoe crab is
one of the most important animals in the

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world. Its strange blue blood may
even save your life. Today's Spotlight is

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on the amazing horseshoe crab. There
are only four different kinds of horseshoe crab.

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Most live in waters around Asia.
One kind lives in the Atlantic Ocean.

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They spend most of their lives under
water, but they do come to

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the surface to mate and to place
their eggs on land. Horseshoe crabs are

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also a very old kind of animal. Scientists have found fossils of horseshoe crabs.

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Some scientists suggest these fossils may be
four hundred and fifty million years old.

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They look quite a bit like today's
horseshoe crabs. The animals have not

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changed much over all that time.
But horseshoe crabs are not just interesting,

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they are also very important for the
medical industry. Every year, companies catch

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thousands of horseshoe crabs. They transport
them to laboratories. There, they collect

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the crab's blue blood in bottles.
Then the companies release them back into the

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sea. This may seem cruel,
but it may be necessary. For many

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years, horseshoe crab blood was the
only way to make sure medicine was safe.

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This is because a horseshoe crab's blood
contains a special chemical called limitless ammabokite

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lisate or loal lal reacts in the
presence of dangerous bacteria called Gram negative bacteria.

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Gram negative bacteria are a very big
problem in medicine. To be safe,

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medicines need to be free of disease. Medicines and vaccines go through a

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long process to make sure every batch
of medication is safe. But Gram negative

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bacteria are very hard to get rid
of. They do not die under high

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heat like other bacteria, they resist
normal cleaning methods, and they contain a

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poison that can harm people even after
the bacteria is destroyed. For a long

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time, scientists at medical companies did
not have a good way to test for

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gram negative bacteria. Instead, they
would test new medicines on rabbits. They

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would inject the rabbits with new medicines. If the rabbits lived, the medicine

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was safe, but if these got
sick, the scientists would need to try

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again. Medical companies needed to keep
thousands of rabbits for this process, and

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the test was not always correct.
But the discovery of LAL in horseshoe crab

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blood changed this. Fred Bang and
Jack Levin were scientists from the United States.

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In nineteen sixty five, they created
the lal test for new medicines.

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It used horseshoe crab blood to test
for gram negative bacteria. It was safer

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and much faster than other tests.
The test results were almost always correct.

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Soon the low test was used in
most countries for developing medicine and every test

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used horseshoe crab blood. Barbara Brummer
leads the Nature Conservant in New Jersey.

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She told National Geographic magazine. All
medical companies around the world need these crabs.

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When you think about it, your
mind is amazed by how much we

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depend on such an ancient creature.
If you have ever had medical work or

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received a vaccine, horseshoe grabs were
involved. If their blood has not saved

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your life yet, it probably will
in the future. However, harvesting horseshoe

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crab blood may be more dangerous to
the survival of these crabs than scientists first

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thought. Most medical companies do not
kill horseshoe crabs when they harvest them.

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They only take about a third of
the animal's blood. Then they release the

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crabs back into the ocean. At
first, scientists believe that this would keep

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the population healthy, but in the
nineteen ninety horseshoe crabs began to disappear.

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When Watson is a scientist at the
University of New Hampshire. He believes that

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horseshoe crabs are dying out because of
blood harvesting. Horseshoe crabs are used to

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living in cool water, but they
can survive on land for several days.

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However, most people harvesting them do
not keep them in water. They do

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not keep them cool. This laboratory
treatment may cause permanent damage. Horseshoe crabs

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that return from harvesting do not give
birth to as many babies, and almost

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a third of them die soon after
their stay in the laboratory. Watson spoke

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to the magazine Popular Mechanics. Name
me another sea creature who breathes under the

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water, who can survive on land
the way they can. You cannot do

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that with a fish. You cannot
do that with a lobster. Horseshoe crabs

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are very strong, but I think
they lose a lot because of it.

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Horseshoe crabs are also hurt when the
places they live are destroyed. People use

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them as bait to catch fish,
and in some countries people consider them a

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special food. But there is hope
for the horseshoe crab Dingjeekling is a scientist

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at the National University of Singapore.
In the year two thousand, she created

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a new test. It comes from
horseshoe crab genes. It also identifies gram

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negative bacteria, but it does not
need horseshoe crab blood to make the new

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test is just as safe as LAL. Today, many people use Cheeklings test.

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Lonza is a medical company from Switzerland. In twenty twenty, they work

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together with Moderna to create a vaccine
against COVID nineteen. To test their vaccines,

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they used cheek Ling's new method.
Still people continue to harvest horseshoe crabs.

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Some do not believe that jake Ling's
test is as good as the Lal

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test. Some make a lot of
money harvesting horseshoe crabs. They do not

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want to change, but jake Ling's
tests are easier to make. They take

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less effort than fishing for thousands of
crabs. There may even come a day

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when harvesting horseshoe crabs may no longer
be necessary. They will be able to

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go back to their lives on the
bottom of the ocean, and they will

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live in peace, just as they
have for thousands of years. You can

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leave a comment on our website or
email us at Radio at Radio English dot

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net. You can also comment on
Facebook at Facebook dot com, Slash Spotlight

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Radio. The writer and producer of
this program was Dan Chrisman. The voices

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you heard were from the United States
and the United Kingdom. All quotes were

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adapted for this program and voiced by
Spotlight. You can listen to this program

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again and read it on the internet
at www dot Radio English dot net.

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This program is called The Amazing Horseshoe
Crab. You can also get our programs

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delivered directly to your Android or Apple
device through our free official Spotlight English app.

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We hope you can join us again
for the next Spotlight program. Good Bye,