Spying on Farm Animals - VOA Special English - Phần 3 ppsx

Spying on Farm Animals
This is the VOA Special English AGRICULTURE REPORT.
Wildlife experts like Jane Goodall are famous for studying animals
in the wild. In recent years, a new kind of scientific study has
developed. More and more experts are studying cows and pigs on
farms. Such experts are called farm animal ethologists. They are
similar to wildlife experts. They observe farm animals in their
natural environment and interfere as little as possible.
The United States Department of Agriculture employs two farm
animal ethologists. They measure stress in farm animals as part of
efforts to improve the way the animals are treated. Stress is a
mental or emotional influence that is harmful to the body.
Julie Morrow-Tesch was the first U-S-D-A farm animal ethologist.
She says stress in animals can cause serious problems. These
include slower growth, disease, injury and sometimes death.
Mizz Morrow-Tesch and her team work from a large vehicle that
has cameras and other equipment. They work near large, open
feeding areas for cattle in the state of Texas. Team members use
hidden cameras or sit on top of the vehicle to study the animals.
They observe the actions of individual cows every fifteen minutes.
Each feeding area has two-hundred or more cattle. The team can
study several feeding areas at the same time. The vehicle keeps
team members hidden from the cattle. The team uses special
night-observation equipment to avoid the need for bright lights.
Mizz Morrow-Tesch and her team studied more than five-thousand
cattle in thirty-one feeding areas. They recorded the cows feeding,
drinking, standing, lying and walking. They also recorded
aggressive actions among the animals.
Their observations already have identified some problems and
possible answers. For example, they found that feeding the
animals just before sunset instead of in the morning reduced

aggression among the animals. Aggressive cattle may injure other
animals.
The team also identified the value of protecting cattle in hot
weather. Cattle kept away from direct sunlight reached their market
weight twenty days earlier than animals in unprotected areas. Also,
the protected cattle weighed about twenty-seven kilograms more
than the other animals.
This VOA Special English AGRICULTURE REPORT was written
by George Grow.
Penguins Dying
This is with the VOA Special English ENVIRONMENT REPORT.
Experts say a shortage of fish and other food is threatening many
of the world's penguins. They say as many as ten of the seventeen
kinds of penguins may be in danger of disappearing.
For example, thousands of Magellanic penguins build their nests at
Punta Tombo, Argentina. Wildlife Conservation Society
researchers have studied these birds for eighteen years. They say
the numbers of penguins have decreased by thirty percent since
Nineteen-Eighty-Seven.
Penguins are black and white birds that live in the southern half of
the world. They are common to South America, New Zealand,
Australia and South Africa. Many live near cold waters. But some
live near warm waters in the Galapagos Islands, near the coast of
Ecuador. Pengins cannot fly. But they are fine swimmers.
Penguins eat fish. Some kinds of penguins eat a small shrimp-like
crustacean called krill.
Many scientists blame global warming for the decrease in penguin
populations. They believe the heating of the atmosphere has
caused ocean waters to become warmer. The scientists say higher
water temperatures have reduced the supply of fish and krill.

Rising air and water temperatures may have especially harmed
Galapagos penguins. Researchers say that some years these
birds are completely unable to reproduce. In addition, many adult
penguins die of hunger.
Widespread fishing, exploration for oil and oil leaks also threaten
penguins. Poisonous organisms in ocean water are another
danger. These toxic blooms result from changes in the ocean
water. Some scientists believe the warming of the oceans is
responsible.
In Nineteen-Ninety, more than half the yellow-eyed penguins in
New Zealand died suddenly. These endangered birds may have
died of a mysterious disease. Penguins also have natural enemies,
including wild dogs, sharks, seals and sea lions.
News about penguins is not all bad, however. About a year ago, oil
leaking from a ship threatened forty percent of the penguins in
South Africa. The penguins became covered with oil. But
thousands of people helped clean and treat the birds. Then they
returned the penguins to the wild. Now these South African
penguins are reproducing in higher numbers than before the oil
spill.
This VOA Special English ENVIRONMENT REPORT was written
by Jerilyn Watson.
Beagle Brigade
By George Grow
This is the VOA Special English AGRICULTURE REPORT.
Diseases, insects and animals all can threaten agriculture. Often
the threat of attack comes from foreign organisms. The United
States Department of Agriculture has many ways to protect
American agriculture. One such method is the Beagle Brigade.
The Beagle Brigade is a group of non-aggressive dogs and their

human partners. The dogs work with U-S-D-A inspectors and X-ray
equipment to prevent the entry of banned agricultural products into
the United States. They search travelers' belongings for banned
fruits, plants and meat that could carry harmful organisms.
All dogs have noses that are well built for smelling. Their noses are
designed to receive and trap smells.
The Animal and Plant Health Inspection Service chose beagles for
use at airports for several reasons. Beagles are intelligent and
active dogs. They are loyal and obey orders. American officials
have found that most beagles will remain calm in crowded, noisy
areas. They also are gentle with people. And they have an
excellent sense of smell.
Experts say beagles can identify smells so weak that even modern
scientific technology could not measure them. Beagles also have
an excellent ability to identify differences among smells. The part of
a dog's brain that receives messages from the nerves of the nose
is highly developed. This area can store information the way a
computer does.
The Agriculture Department established its program with dogs in
Nineteen-Eighty-Four. At first, different kinds of dogs were used.
Then officials worked with the armed forces in Texas to train
Beagle Brigade teams. In Nineteen-Eighty-Seven, the Department
opened three training centers and began training its own teams.
Now the Beagle Brigade has more than fifty teams at twenty-one
international airports. More teams are being added. Plans are
being made to deploy teams along the American border with
Mexico. Plans also call for the use of dogs at some mail centers.
U-S-D-A officials also have provided help to agriculture officials in
other countries who want to start their own dog programs. Officials
in Australia, Canada, Guatemala, Mexico, New Zealand and South

Korea have asked for help.
This VOA Special English AGRICULTURE REPORT was written
by George Grow.
Apes Endangered
By Cynthia Kirk
This is the VOA Special English ENVIRONMENT REPORT.
Great apes are the animals most like humans. Experts say that
great apes in the forests of Africa and Asia will disappear within ten
years if nothing is done to save them. The United Nations
Environment Program has begun a campaign called the Great Ape
Survival Project.
Its members are working with wildlife groups and non-
governmental organizations. Their goal to prevent the
disappearance of gorillas, bonobos, chimpanzees and orangutans.
The project targets areas in Africa and southeast Asia where apes
are threatened by war, environmental destruction and hunting.
Ten years ago, there were more than six-hundred mountain
gorillas in eastern and central Africa. Today, there are only about
three-hundred. They are disappearing from forests in the
Democratic Republic of Congo, Rwanda and Uganda. Many of
them are being killed for food as part of the growing illegal bush-
meat trade.
Congo was once a safe area for gorillas. But years of war and
forest destruction have made the gorillas easier targets for hunters.
Miners searching for minerals also hunt the great apes. The
gorillas that are left have to be protected by armed soldiers in
national parks.
Bonobos are small apes found only in the forests of Congo. Twenty
years ago, there were about one-hundred-thousand bonobos.
There are only about three-thousand today. Some bonobos have

fled to nearby countries. Most of them are being hunted for food.
Many chimpanzees have died out in countries where they once
lived. Fifty years ago, there were millions of chimpanzees across
western and central Africa. Today, only about one-hundred-fifty-
thousand chimpanzees remain.
The orangutan is endangered in Indonesia's rainforests. The
rainforests are shrinking because of farming, cutting down trees
and gold mining in protected areas.
Environmental experts say apes need more protection in national
parks. They say local people need to be educated about the value
of apes and their importance to the environmental system. Experts
say the apes are important for scientific study because they are so
closely related to humans.
United Nations officials say they need one-million dollars to support
the Great Ape Survival Project. They want private companies to
assist in the campaign.
This VOA Special English ENVIRONMENT REPORT was written
by Cynthia Kirk.
Ancestor of Humans
By Jill Moss
This is the VOA Special English SCIENCE REPORT.
Scientists have discovered an extremely small animal they believe
could have been the ancestor of all mammals, including humans.
The animal lived one-hundred-ninety-five million years ago. It
weighed only about two grams. Yet researchers say it had
important qualities that link it to mammals. Mammals are warm-
blooded animals that feed their young milk from their bodies.
A team of American and Chinese researchers discovered ancient
remains of the animal's head bone in southwestern China. Zhe-Xi
Luo of the Carnegie Museum of Natural History led the

researchers. Their findings were published last month in Science
magazine.
The scientists say the animal was one of the smallest mammals
that ever lived. But they say the animal's brain was large compared
to other mammals. Mr. Luo said the ancient animal had to be very
smart because it was able to survive in a world controlled by huge
dinosaurs.
The researchers named the tiny animal Hadrocodium wui, which
means "large and full head" in the Greek language. Scientists say
Hadrocodium was only a little bigger than the smallest mammal
now in existence - the bumblebee bat of Thailand.
Mr. Luo says Hadrocodium probably ate insects. And it probably
had to eat all the time because of its small size. Researchers also
believe the ancient animal had to hide during the day when
dinosaurs were hunting. This meant Hadrocodium was able to
keep a continuous body temperature in the cold night air.
The researchers compared Hadrocodium's skull to other ancient
and modern-day mammals. They say Hadrocodium could be the
closest known ancestor of living mammals.
The researchers discovered that the ancient animal had middle ear
bones that separated from the lower jaw bone. This is an important
quality that separates mammals from the cold-blooded animals
called reptiles. The researchers also discovered that Hadrocodium
had a large head bone. This suggests that its expanding brain may
have pushed the middle ear bones away from the jaw. Mr. Luo say
the ancient remains of Hadrocodium prove that some qualities of
mammals developed about forty-five-million years earlier than they
had believed.
This VOA Special English Science Report was written by Jill Moss.
Insects to Control Harmful Trees

By George Grow
This is the VOA Special English ENVIRONMENT REPORT.
Researchers are planning to use natural enemies to stop the
spread of a harmful tree in the American state of Florida. The
melaleuca tree threatens to spread throughout the Everglades. The
Everglades is a system of wetlands that is home to many kinds of
plants and animals.
Scientists with the Agricultural Research Service have been
exploring natural methods to control the melaleuca. The tree is
native to Australia. In that country, more than one-hundred kinds of
insects feed on it and keep it under control. The melaleuca was
first brought to the United States in the early Nineteen-Hundreds.
But it had no natural insect enemies in its new environment. So
melaleuca trees spread uncontrolled across the southern United
States.
The tree kills and replaces other plant life in the Everglades. It is
now blamed for environmental losses of up to one-hundred-
seventy million dollars a year.
The Fergusonina fly is a natural enemy of the melaleuca. An
extremely small worm, called a nematode, lives inside the fly. A
team of American scientists is working with the Australian
Biological Control Research Laboratory. They collected
Fergusonina flies from Australia. The scientists put the flies on test
plants to see if they attacked them. They found that the flies are
likely to survive and reproduce only on the melaleuca trees in
Florida. The flies would not harm other plants. This information was
important for officials who approved a request to send thousands
of flies to the University of Florida for additional tests.
Ted Center is the chief of the Agriculture Department's Invasive
Plant Research Laboratory. He says tests show that the

Fergusonina fly and the nematode are genetically different from
other insects that attack other plants. He says this means that they
eat, live and reproduce only in one kind of plant. The scientists now
are planning more testing before proposing the release of the
insects in the Everglades.
Four years ago, scientists from Florida and Australia released
another natural enemy of the melaleuca, the snout beetle.
Scientists have released more than fifty-thousand of those insects
in south Florida. The scientists believe the Fergusonina fly and
nematode would help the beetle and strengthen the effort against
the melaleuca trees.
This VOA Special English ENVIRONMENT REPORT was written
by George Grow.
Dolphins' Self-Recognition
By Jill Moss
This is the VOA Special English SCIENCE REPORT.
Many people believe that dolphins are among the smartest animals
on Earth. Dolphins are warm-blooded sea animals. Recently,
scientists discovered that dolphins could do something that
humans can do. They say dolphins can recognize themselves in a
mirror, a shiny piece of glass.
Scientists Diana Reiss and Lori Marino discovered this special skill.
They did separate studies with two bottlenose dolphins at the New
York Aquarium in Brooklyn, New York. Their findings were
published in a National Academy of Sciences publication.
The researchers say their study proves that dolphins have a high
level of intelligence. Mizz Reiss and Mizz Marino say that dolphins
have a level of self-knowledge because they are able to recognize
themselves in mirrors. This level of self-knowledge has been
identified only in humans and one other kind of animal - the great

apes.
The two researchers discovered this by using a test created thirty
years ago by scientist Gordon Gallop. Mr. Gallop placed a mark on
animals. He wanted to find out if the animals were able to
recognize themselves in a mirror. He found that when animals
study the marking in a mirror, they show signs of self-recognition.
Mizz Reiss and Mizz Marino tested the two dolphins many times
with two markers. They used one marker filled with ink that made
real marks. They also used a marker filled with water that did not
make a mark. Each dolphin repeatedly swam to the mirror to
inspect the place where it had been marked with ink. The scientists
say the dolphins turned and positioned themselves to get a better
look in the mirror.
Mizz Reiss says that most animals either refuse to look at a mirror.
Or they react aggressively as if the image were another animal.
Experts say this new research provides more information about
how the brain develops. During the past sixty-million years, the
brains of dolphins and primates have developed differently.
Primates include humans, apes and monkeys. For example,
dolphin brains lack a front part, or lobe, found in primate brains.
Also, one area of dolphin brains is organized differently from that of
primates. Mizz Reiss says that even though these animals have
developed differently over time, their brains have developed a
similar intelligence.
This VOA Special English Science Report was written by Jill Moss.
Alligators' Success Story
By Paul Thompson
This is Steve Ember. And this is Shirley Griffith with the VOA
Special English program, EXPLORATIONS.
Not too long ago, the American alligator was in danger of

disappearing from the Earth. Today we tell the success story of this
animal.
When Spanish explorers reached what would become the southern
State of Florida, they found a long, fierce green animal. It had a
wide head and a large mouth that opened to show up to eighty
teeth. The Spanish explorers called this dangerous creature "El
lagarto." The words mean, "the lizard." In time the Spanish words
would change to the modern English word, "alligator."
For many years, the huge green animals were hunted and their
territory destroyed. Their tough, beautiful skin was made into
shoes, belts and other leather products. Their natural territory was
used to build roads, streets, homes and cities. For years the
American alligators were disappearing faster than they could
reproduce. Scientists knew the animal was in danger of
disappearing from the Earth.
In Nineteen-Sixty-Seven, Congress approved a law that would
protect the American alligator. The United States Fish and Wildlife
Service announced rules for saving the animals.
To better understand the situation, come with us for a few minutes.
We will take you to a large hole filled with water that is the home of
an American alligator.
The water hole is in the extreme southern part of the state of
Florida. It is in a land area protected by the federal government
the Everglades National Park.
((MUSIC BRIDGE))
A large green animal slowly comes to the surface of the water. At
first, only its eyes and front of its long nose can be seen above the
water. It moves very slowly in the water without effort. Its long tail
moves slowly from side to side. From its nose to the end of its tail it
is almost three meters long.

The animal is hungry. But it is in no hurry. It caught and killed a
small deer several days before. It attacked the deer that had come
to the water to drink. Then it hid the dead deer under water. Now
the alligator wants to eat.
It is the hot dry summer season now. There has been little rain for
several weeks. The huge reptile dug this large hole that is filled
with water.
Digging the hole has taken the alligator several years. Each year
the hole became bigger and deeper. Digging was slow hard work.
As the animal dug with its short legs, it pushed away the plants it
found. Some of the plants grew around the outside of the hole.
Seeds from trees blew into the area and grew where the alligator
had pushed dirt and mud out of the hole. Now, the huge water filled
hole was surrounded by many different kinds of plants and trees.
Millions of liters of water are just below the surface of the ground,
so the large hole is always filled with fresh, clear water. In the dry
season, other animals come here for the needed liquid. Other
animals and birds are able to survive the dry season because of
the water hole. And, the other animals became a fresh supply of
food for the dark green alligator, which did not have to leave home
to hunt.
This alligator is a large female. Several weeks before, she had built
a nest above the water. She had laid almost forty eggs. Each egg
was just a little larger than that of a chicken.
She had covered the nest with wet plants and mud. She had been
carefully guarding the nest since she placed the eggs there. The
sun and plants had kept the nest and the eggs warm.
Early this morning she heard the sound young alligators make
when they have left the egg. Because the eggs were so well
protected by the nest, the young alligators can not climb out.

The mother alligator opens the nest area to permit the small
reptiles to enter the water. They weigh only about sixty grams
each. They are about twenty centimeters long. As the young leave
the nest, birds come to the area. Within an hour, birds eat twelve of
them.
The mother alligator tries to protect her young. She will protect
them for almost three years. But even an alligator can not protect
all of the young that leave the nest. Until they grow large enough,
the young alligators are in danger of being eaten by birds and other
animals.
Yet in time, each of the young alligators who survive will become a
fierce looking animal up to four meters long. Each one will be a
ruler of its own small area. Each one will be a dangerous hunter.
((MUSIC BRIDGE))
The story we just told could have taken place ten thousand years
ago. Or it could be taking place today. The alligator is a very
ancient and successful creature. It has not changed much since
the time huge reptiles called dinosaurs ruled the Earth.
The Everglades National Park is home to many thousands of these
huge green animals. When the alligators began to disappear,
scientists started to understand the effect of the animals on the
environment of the Everglades area.
Without the alligators to help provide water, other animals could
not survive the dry season. Without the water holes dug by the
alligators, fewer plants and trees would grow in the area. Scientists
discovered that one kind of turtle places its eggs near the alligator's
nest. The turtle depends on the alligator to survive. The turtle is
only one of several animals that needs the water provided by the
alligator.
The American alligator is a real success story. It is a good example

of how federal and state laws helped an animal increase in
numbers.
In Nineteen-Sixty-Seven, the Federal Government declared the
alligator to be endangered. Laws were passed that said it could no
longer be hunted. The government also approved laws to make it
illegal to buy and sell products made from alligator skin.
Government scientists began projects in Louisiana, Florida,
Georgia Texas and South Carolina. These are states where the
alligator is found in the wild.
The projects called for some alligators to be raised on farms. More
than one-hundred-fifty alligator farms were built in the states of
Florida, Louisiana, and Texas. All of these farms were linked to a
central program that supervised the project to increase the number
of alligators.
Scientists started the farms by collecting eggs and young alligators
from their natural area. These alligators were cared for and
protected.
The young alligators were returned to natural areas when they
became large enough to survive on their own. About seventeen
percent of the alligators raised on farms were returned to the wild.
Others were kept on the farms to reproduce.
In a little more than ten years, the number of the animals surviving
increased. Government records now show that more than three-
hundred-fifty-thousand alligators live on farms. Many of these
farms no longer belong to the government. They are businesses
that use the alligator as a crop.
Leather products from the alligator can once again be found for
sale. Some eating places offer alligator meat. However the farms
and alligator products still are carefully controlled.
The federal government also learned that helping the alligator

recover called for educating the public about what can be a very
dangerous animal. In the past, alligators were killed if they came
anywhere near a population center. Now, special workers remove
them if possible and take them back to wild areas.
The public has been taught about how to live with alligators. For
example, Alabama now has about thirty-five thousand alligators
living in natural areas. State records show there have been only
five recorded alligator attacks on people. While these attacks were
serious, no one was killed.
In Nineteen-Eighty-Seven, the federal government declared the
American alligator to be fully recovered. It was no longer
considered to be an endangered animal. Yet many protection
measures remain in place to make sure the population of alligators
does not decrease.
Today, visitors to the southern state of Florida can see many
alligators at the Everglades National Park. Park workers show
visitors alligator water holes, young alligators, and huge adults.
Alligators can also be seen in great numbers in many other areas
where they live in the wild.
The alligator is a success story today because of the work of the
United States Fish and Wildlife Service. Yet it is only one animal
the agency is working to help survive. Five-hundred-eleven
animals are on the list of those that need help if they are to survive
into the future.
(MUSIC)
This program was written and produced by Paul Thompson. Our
studio engineer was Keith Holmes. This is Steve Ember.
And this is Shirley Griffith. Join us again next week for another
EXPLORATIONS program in Special English on the Voice of
America.

Dinosaurs and Birds
By Mario Ritter
This is the VOA Special English SCIENCE REPORT.
A debate has continued in the scientific community concerning the
ancestors of modern birds. Some scientists believe birds
developed from the ancient creatures called dinosaurs. Others
believe birds developed separately.
A recent discovery seems to support the idea that birds developed
from dinosaurs. Nature magazine has published a report by
Chinese and American researchers. It describes the first clear
evidence of a dinosaur with feathers. Ji Qiang of the Chinese
Academy of Geological Sciences in Beijing and Mark Norell of the
American Museum of Natural History in New York wrote the report.
Fossils are the mineral remains of bones buried millions of years
ago. The fossil of a feather-covered dinosaur was discovered in
Liaoning Province in northeastern China. Several fossils of
dinosaurs with feathers have been found in this area of China. But,
it is not always easy to confirm fossil discoveries.
Last year, we reported that a fossil dinosaur with feathers was
found to be false. But, this most recent discovery appears to be
confirmed.
The dinosaur was about a meter long. It walked on two legs and
had a feather-like covering all over its body. The small dinosaur did
not have wings and could not fly. But some of its bone structure
was similar to that of birds. The animal lived about one-hundred-
thirty-million years ago.
Hans-Dieter Sues of the Royal Ontario Museum in Toronto,
Canada says the fossil evidence shows that non-flying dinosaurs
had a feather covering. Mr. Sues says the most recent fossils
provide strong evidence that birds developed from dinosaurs.

Both Chinese and American researchers now believe that feathers
developed to keep dinosaurs warm. They believe that some
dinosaurs may have been warm-blooded like mammals and birds
are today. For many years, paleontologists studying dinosaurs
have thought that some dinosaurs may have been warm-blooded.
Now the confirmed discovery of a non-flying dinosaur with feathers
appears to support that theory.
The theory that feathers covered many dinosaurs requires a great
change in the way we imagine those ancient creatures. In the Latin
language, "dinosaur" means "terrible lizard." Instead, dinosaurs
may have looked like terribly large birds.
This VOA Special English SCIENCE REPORT was written by
Mario Ritter.
Spiders and Silk
By Jill Moss
This is the VOA Special English SCIENCE REPORT.
Spiders are very small. So it is easy to think that they do not make
anything strong. However, a scientist at Oxford University in Britain
has discovered this it not true. David Knight says that eight-legged
spiders create a material called silk that could be as strong as
rope.
Mr. Knight has been studying spiders and the natural silk material
they produce for many years. The main subject of his research is
the complex chemical process that spiders use to make their silk.
Mr. Knight's findings were published recently in the British
magazine, Nature.
Mr. Knight says that silk is very thin. But it is extremely strong. This
is because the threads of silk are made into a complex structure.
Mr. Knight says the silk is made from protein molecules. It forms in
the parts of the spider's body called silk glands. The silk is like

pieces of string. It is rolled into small balls.
When the spider wants to make, or spin, some silk, it carefully
unrolls the balls. The pieces of string join together. When the
spider wants to move, it joins all the small strings of silk into one
long thread. Then it can move down the thread. Wherever a spider
goes, it spins a silk thread behind itself.
Mr. Knight says that spiders can make and use as many as seven
kinds of silk. It uses one kind of silk for making the structure of the
spider's web where it traps insects. It uses another stretchy silk
for making round links in the web. Mr. Knight says those links are
covered by another kind of silk that is very sticky. This sticky
material makes it difficult for insects to escape after they are
caught in the spider's web.
Spider silk is strong enough to catch insects. Its strength can be
measured. Mr. Knight says the silk from an Orb web spider is five
times stronger than fiber made by man. He also estimates that a
rope of spider silk as thick as one pencil could pull a large ship
through the water. He says one day people may be able to make
material as strong as a spider's silk. It could be used in place of
rope.
Spider silk is a useful material. It does not harm the environment. It
can be re-used by spiders. So people may wonder why they
cannot use spiders to manufacture silk for industrial use. Mr.
Knight says it is because spiders can not be farmed. He says if you
put them in a room together, they will try to eat each other.
This VOA Special English Science Report was written by Jill Moss.
Oregon Frog Study
By Cynthia Kirk
This is the VOA Special English ENVIRONMENT REPORT.
Scientists have tried for years to understand what is causing frogs

to disappear around the world. Since Nineteen-Eighty, at least
twenty kinds of frogs have disappeared. Many explanations have
been proposed. They include pollution, infections and unidentified
environmental threats.
Scientists have warned about the possible harm to the
environment caused by warming of the Earth. Now researchers
say they have evidence that climate change could be a cause of
the frog deaths. The findings are the first to link climate change
with the decreasing frog population in North America.
A team of researchers studied frog eggs in small bodies of water in
the northwestern American state of Oregon. Joseph Kiesecker led
the study in Oregon's northern Cascade Mountains.
Scientists have known for years that frog eggs in the western
states are dying from a fungal infection in water. The latest
research suggests that the infection is the result of a complex
series of events caused by warming temperatures.
The scientists believe the frogs' eggs become infected because
water levels where the eggs are laid are too low. They say climate
change has reduced the amount of rainfall in areas where the frogs
lay their eggs. Lower water levels permit more dangerous
ultraviolet light from the sun to reach the eggs. Ultraviolet radiation
can cause the eggs to lose their ability to resist deadly fungal
infections.
The researchers had done other experiments in the mountains. In
those studies, scientists thought that ultraviolet radiation from the
decreasing amount of ozone in the atmosphere was causing the
frog deaths. Ozone in the upper atmosphere blocks ultraviolet
radiation from the sun.
Some scientists disagree with the new study. They say the effects
of ultraviolet radiation in Oregon probably would not happen

anywhere else. They also disagree about whether the fungal
infection is the direct cause of the frog deaths. Some scientists say
the fungus could have developed in the eggs after they had
already died of a different cause.
Scientists note that not all of the world's frogs lay their eggs in
water. They say there are probably many reasons for the
decreasing populations of frogs around the world.
This VOA Special English ENVIRONMENT REPORT was written
by Cynthia Kirk.
Sleeping Rats Dream
By George Grow
This is the VOA Special English SCIENCE REPORT.
A new American study offers strong evidence that animals dream
about their daily experiences.
Scientists in Massachusetts performed laboratory experiments with
four rats. They found that the sleeping rats' brains showed activity
that suggested dreaming. The scientists say the animals appeared
to be remembering real life events. They say the rats could be
using dreams to learn or to memorize, much the way humans do.
The publication Neuron reported the findings.
Matthew Wilson of the Massachusetts Institute of Technology in
Cambridge organized the study. The scientists placed tiny
electrode devices in the brains of the rats. The devices measured
activity in a part of the brain called the hippocampus. In humans,
the hippocampus is involved in forming and storing memories.
Mr. Wilson and an assistant trained the rats to run through a series
of complex passages called a maze. They gave the animals food
for successfully completing each run.
The scientists measured the brain activity of the rats while the
animals were running through the maze. They also measured brain

activity when the rats slept. Experts say animals have the same
kinds of sleep periods that people do. They say animals
experience periods of rapid eye movement sleep. This is a deep
sleep period when people have dreams.
The scientists examined the rats' brain activity during rapid eye
movement sleep. They say the brain activity was almost exactly
the same as when the animals were running through the maze.
The scientists believe the rats were dreaming about running.
Experts have long thought that animals dream. Mr. Wilson says the
study suggests that the brains of rats are more complex than had
been believed. He says the findings could help scientists better
understand how the human mind works.
Some scientists praised the study. They say the technology opens
new possibilities for understanding sleep and dreams. Other
scientists say the findings support the idea that sleep is important
for learning and storing memories. However, still other scientists
say more studies and investigation are needed.
This VOA Special English SCIENCE REPORT was written by
George Grow.
Genetically Engineered Monkey
By Mario Ritter
This is the VOA Special English SCIENCE REPORT.
American scientists have created the world's first genetically
engineered monkey. A team of scientists at the Oregon Regional
Primate Research Center did the research that led to the birth of
the monkey.
The scientists took a gene from a kind of jellyfish. They put it into a
special virus that does not cause infection. Then they put the virus
into more than two-hundred eggs from rhesus monkeys. Only forty
of the eggs were successfully fertilized and began to develop. The

scientists placed the fertilized eggs into twenty female monkeys.
Three baby monkeys were born and survived. One monkey carried
the jellyfish gene.
The gene from the jellyfish makes a protein that looks green under
blue light. The gene was chosen because it produces an effect that
can be seen. However, no part of the monkey appears green under
blue light. The scientists say the jellyfish genes are in the cells of
the monkey. But, they say the genes are not fully working in the
cells.
The method used to place genes from one kind of animal into
another is not new. The method has been used since Nineteen-
Seventy-Six. The process has been used to genetically engineer
fruit flies, cows, pigs, and other animals. However, this is the first
time scientists have genetically changed a member of the group of
animals that includes monkeys, apes and humans.
Head researcher Gerald Schatten says the experiment shows that
genetic engineering works. He said his goal is to create monkeys
that have been genetically engineered to develop human diseases.
Scientists could then use the animals to study new treatments for
humans with the disease. However, he says the value of the work
remains uncertain because of the many problems involved in the
process. The scientists published their findings in the publication
Science. Other scientists disagreed about the importance of the
research.
Rudolph Jaenisch of the Massachusetts Institute of Technology
says using a virus to put genes into an egg is not an effective
method. He says this method only creates animals with added
genes. He says most human genetic diseases are caused by a
missing or abnormal gene.
This VOA Special English SCIENCE REPORT was written by

Mario Ritter.
Rare Animal Clone Dies
By George Grow
This is the VOA Special English SCIENCE REPORT.
American scientists have reported producing the first exact copy of
a rare animal.
The baby gaur was born on January eighth in the state of Iowa. He
died two days later from a common bacterial infection. The
scientists say the infection probably did not result from the
methods of cloning they used to create him.
The gaur successfully grew and developed inside a common cow.
Experts say he is the first clone ever born to another kind of
animal.
Gaurs are native to India and southeast Asia. The wild oxen are
generally brown or black in color. In recent years, hunting by
humans has sharply reduced the gaur population. Only about
thirty-thousand of the animals are believed to exist.
The baby gaur was created with the cells of a male gaur that lived
at the San Diego Zoo in California. That gaur died eight years ago.
Zoo officials saved his skin cells for future experiments.
Scientists with an American company, Advanced Cell Technology,
supervised the project. The scientists removed genetic material
from hundreds of cow eggs. Then, they added the gaur cells to the
eggs. They say this helped to guarantee that the resulting animal
would not be a mix between a gaur and a cow.
Only one successful pregnancy resulted from the experiment. The
scientists named the baby gaur Noah. He weighed thirty-six
kilograms when born and seemed healthy. However, he quickly
developed a bacterial disease common among young animals. The
scientists were unable to save his life.

The scientists say they are sad that the animal died. They say
Noah was full of energy and friendly during his short life. However,
they are pleased that the experiment was successful.
The American company is planning other projects. The scientists
hope to produce a clone of a wild mountain goat native to Spain.
They plan to use cells from the last known bucardo goat, which
died last year. No other bucardos are know to exist.
The successful cloning of a gaur suggests that other rare animals
could be brought back into existence. Yet, wildlife activists note
that the technology is costly. And, they say there is no reason to
create more rare animals if nothing is being done to deal with the
causes of their disappearance.
This VOA Special English SCIENCE REPORT was written by
George Grow.
Cats in America
By Jerilyn Watson
An old expression says, "Man's best friend is his dog." Today,
however, it seems that cats have replaced dogs as the most
popular pets in American homes. I'm Shirley Griffith. And I'm Steve
Ember.
Today we report on Americans and their cats on the VOA Special
English program, THIS IS AMERICA.
Americans have more than sixty-two million pet dogs. But even
more cats more than sixty-four million live in American homes.
These pet cats may have long hair or short hair. They are different
colors and sizes. Some are costly animals that take part in
competitions. Many more are common American mixtures of
several kinds of cats.
Most house cats live a good life. They are not expected to work for
their food. Instead, they rule their homes like furry kings and

queens. They wait for their owners to serve them.
Americans are increasingly serious about their cats. These
concerns have made the care of cats into big business.
Each year, cat-owners buy tons of food especially prepared for
cats. They buy toys and other equipment. They buy jewelry and
clothes for themselves with images of cats on them. Some owners
even bury their dead pets in special burial grounds.
Humans have loved and respected cats for centuries. Scientists
have evidence that cats and people lived together as long as eight-
thousand years ago. The small house cat was once a highly
honored animal. In ancient Egypt, for example, people who killed a
cat could be punished by death.
Early in American history cats were not treated as gods, however.
They probably arrived in the United States with settlers and traders
from Europe. These cats worked. They killed rats and mice.
Sometimes, Americans mistreated their cats. During the early days
of the nation, religious extremists believed that some cats were
working for the devil. Black cats were especially suspected of
being evil.
Later, American families who had enough food began taking cats
into their homes. People cared for the cats because the animals
gave them pleasure. The cats thanked people for feeding them by
making a purring sound. This pleasant noise usually means a cat is
happy.
((BRIDGE MUSIC))
Animal experts offer several reasons why cats have become so
popular as house pets. They say cats need less care than dogs.
And cats do not seem to suffer as much as dogs from being alone
if the owners are away.
Still, millions of other people do not like cats at all. They say dogs

are better and more loving pets. They say cats do not have much
feeling. They believe cats stay with people only to be fed.
Cat owners defend their pets against such criticism. They say cats
are just much more independent than dogs.
A student of animal medicine explains the situation this way: Dogs
follow you around. They want you to talk to them and play with
them a lot of the time. Cats like more space and more privacy. This
does not mean they do not love their owners.
Cat owners often like to read about cats. Many books about cats
are in American libraries and bookstores. Cats also appear as the
heroes of newspaper comics, television programs and movies.
Among the most famous is Garfield. He is an orange, striped tiger
cat.
Garfield eats too much. His owner, Jon, is always trying to get the
cat to lose weight. However, Garfield usually eats what he wants.
He often shows more intelligence than his owner.
Some cat lovers raise and show costly, pure-bred cats at special
competitions. The United States has a number of organizations
that investigate cats before declaring them pure-bred. A pure-bred
cat has ancestors who were only a single kind of unusual cat like
the Siamese or the Manx.
One such organization is the Cat Fanciers Association,
incorporated, in the eastern city of Manasquan (Man' ah skwahn),
New Jersey. The Cat Fanciers organization recognizes more than
thirty-five kinds of pure-bred cats. It says Persians and Maine
coons are some of the most popular cats in America today.