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The Amazing Horseshoe Crab (Advanced Program) · Spotlight English: Advanced

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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,