La Brea Tar Pits

(THEME)

VOICE ONE:

This is Faith Lapidus.

VOICE TWO:

And this is Steve Ember with EXPLORATIONS in VOA Special English.
Today we tell about an unusual scientific research area in the
United States.

It is filled with the remains of
ancient animals. This unusual place is in the center of Los Angeles,
California. Its name is Rancho La Brea. But most people know it as
the La Brea Tar Pits.

(THEME)

VOICE ONE:

To understand why La Brea is an important scientific research
center we must travel back through time almost forty-thousand years.
Picture an area that is almost desert land. The sun is hot. A
pig-like creature searches for food. It uses its short, flat nose to
dig near a small tree. It moves small amounts of sand with its nose.
It finds nothing. The pig starts to walk away, but it cannot move
its feet.

They are covered with a thick, black substance. The pig shakes
one foot loose, but the others just sink deeper. The more it
struggles against the black substance, the deeper it sinks. The pig
attempts to free itself again and again. It now screams in fear and
fights wildly to get loose.

Less than a kilometer away, a huge cat-like creature with two
long front teeth hears the screams. It, too, is hungry. Traveling
across the ground at great speed, the cat nears the area where the
pig is fighting for its life.

The cat jumps on the pig's back. It sinks its long teeth into the
pig's neck. The pig dies quickly, and the cat begins to eat. Almost
an hour passes before the cat is finished. When it attempts to
leave, like the pig, it finds it cannot move. The more the big cat
struggles, the deeper it sinks into the black substance.

Before morning, the cat is dead. Its body, and the bones of the
pig, slowly sink into the sticky black hole.

(MUSIC)

VOICE TWO:

Scientists say the story we have told you happened again and
again over a period of many thousands of years. The black substance
that trapped the animals came out of the Earth as oil.

The oil dried, leaving behind a partly solid substance called
asphalt. In the heat of the sun, the asphalt softened. Whatever
touched it would often become trapped forever.

In seventeen-sixty-nine, a group of Spanish explorers visited the
area. They were led by Gaspar de Portola, governor of Lower
California.

The group stopped to examine the sticky black substance that
covered the Earth. They called the area "La Brea" the Spanish words
for "tar."

Many years later, settlers used the tar, or asphalt, on the tops
of their houses to keep water out. They found animal bones in the
asphalt, but threw them away. In nineteen-oh-six, scientists began
to study the bones found in La Brea. Ten years later, the owner of
the land, George Allan Hancock, gave it to the government of Los
Angeles. His gift carried one condition. He said La Brea could only
be used for scientific work.

VOICE ONE:

Today, the La Brea Tar Pits are known to scientists around the
world. The area is considered one of the richest areas of fossil
bones in the world. It is an extremely valuable place to study
ancient animals. Scientists have recovered more than one-million
fossil bones from the La Brea Tar Pits. They have identified more
than six-hundred-fifty different kinds of animals and plants. The
fossils are from creatures as small as insects to those that were
bigger than a modern elephant. These creatures became trapped as
long ago as forty-thousand years. It is still happening today. Small
birds and animals still become trapped in the La Brea Tar Pits.

(MUSIC)

VOICE TWO:

Rancho La Brea is now the home of
a modern research center and museum. Visitors can see the ancient
fossil bones of creatures like the imperial mammoth and the American
mastodon. Both look something like the modern day elephant, but
bigger.

The museum has many fossil remains of the huge cats that once
lived in the area. They are called saber-toothed cats because of
their long, fierce teeth. Scientists have found more than
two-thousand examples of the huge cats. The museum also has many
ground sloths and thousands of fossil remains of an ancient kind of
wolf. Scientists believe large groups of wolves became stuck when
they came to feed on animals already trapped in the asphalt.

VOICE ONE:

Since nineteen-sixty-nine,
scientists have been digging at one area of La Brea called Pit
Ninety-One. They have found more than forty-thousand fossils in Pit
Ninety-One. More than ninety-five percent of the mammal bones are
from just seven different animals. Three were plant-eaters. They
were the western horse, the ancient bison and a two-meter tall
animal called the Harlan's ground sloth.

Four of the animals were meat-eating hunters. These were the
saber-tooth cat, the North American lion, the dire wolf and the
coyote. All these animals, except the dog-like coyote, have
disappeared from the Earth.

VOICE TWO:

Researchers say eighty percent of the fossils found are those of
meat-eating animals. They say this is a surprise because there have
always been more plant- eaters in the world. The researchers say
each plant-eater that became trapped caused many meat-eaters to come
to the place to feed. They, too, became trapped.

Researches say the number of large animals caught in the tar pits
represents only about three every ten years. Many more escaped.
However, this represents many large animals over a period of several
thousand years.

Visitors often ask if the bones of any dinosaurs have been found
at La Brea. The answer is no. Dinosaurs disappeared about
sixty-five- million years before animals first became trapped at La
Brea. The La Brea area and much of California was part of the
Pacific Ocean when dinosaurs were alive in North America.

VOICE ONE:

Rancho La Brea has also been a trap for many different kinds of
insects. Scientists free these dead insects by washing the asphalt
away with special chemicals. The La Brea insects give scientists a
close look at the history of insects in southern California.

The La Brea Tar Pits have also provided science with interesting
information about the plants that grew in the area. For many
thousands of years, plant seeds landed in the sticky asphalt. The
seeds have been saved for research. Scientists also have found
pollen from many different kinds of plants.

The seeds and pollen, or the lack of them, can show severe
weather changes over thousands of years. Scientists say these
provide information that has helped them understand the history of
the environment. The seeds and pollen have left a forty-thousand
year record of the environment and weather for this area of
California.

(MUSIC)

VOICE TWO:

Thousands of visitors come each year to see fossils that have
been found at Rancho La Brea. They visit the George C. Page Museum.
Mister Page was a wealthy man who became very interested in the
scientific work being done at the tar pits. He gave the money to
build the museum and research center.

At the museum, visitors can watch scientists dig bones from La
Brea's Pit Ninety-One. The scientists dig very slowly, using small
tools similar to those used by a doctor to examine teeth. They also
use toothbrushes and cleaning fluids to help soften and clean away
the asphalt.

VOICE ONE:

Visitors to the museum can also see the "fish bowl," a laboratory
surrounded by glass. Here, they can watch scientists do their
research. Visitors can watch the scientists clean, examine, repair
and identify fossils that are still being discovered. Through this
process, scientists are able to answer questions and solve puzzles
about animals and their environment from thousands of years ago.

It is exciting to stand only a few meters away and watch
scientists clean the asphalt off a fossil that is thousands of years
old. Visitors quickly learn why researchers consider Rancho La Brea
a very special place.

If you have a computer that can link with the Internet, you can
visit the Rancho La Brea Page Museum. Have your computer search for
the Spanish words "La Brea." L-A-B-R-E-A, and look for the Page
Museum link.

(MUSIC)

VOICE TWO:

This program was written by Paul Thompson. It was produced by
Mario Ritter. This is Steve Ember.

VOICE ONE:

And this is Faith Lapidus. Join us again next week for another
EXPLORATIONS program in VOA Special English.