Lesson 13:Sylvia Earle and the Deep Ocean

Transcription

Lesson 13:Sylvia Earle and the Deep Ocean
Level: T
DRA: 44
Genre:
Biography
Strategy:
Monitor/Clarify
Skill:
Main Ideas and Details
Word Count: 1,370
6.3.13
HOUGHTON MIFFLIN
Online Leveled Books
1032947
H O UG H T O N M IF F L IN
by Antonio Hattingh
ILLUSTRATION CREDITS: 8 Studio Montage
PHOTOGRAPHY CREDITS: Cover © Macduff Everton / Corbis; 1 © Ralph White / Corbis; 2 © PhotoDisc; 3 © Macduff
Everton / Corbis; 4 © Bettmann / Corbis; 5 © Bettmann / Corbis; 6 © Roger Ressmeyer / Corbis; 9 © Ralph White /
Corbis; 10 © Jeffrey L. Rotman / Corbis; 11 © OAR / National Undersea Research Program (NURP); 13 © david gregs /
Alamy; Bkgrnd © PhotoDisc
Copyright © by Houghton Mifflin Company. All rights reserved.
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Address inquiries to School Permissions, Houghton Mifflin Company, 222 Berkeley Street, Boston, MA 02116.
Printed in China
ISBN-13: 978-0-547-02824-8
ISBN-10: 0-547-02824-5
1 2 3 4 5 6 7 8 9 NOR 15 14 13 12 11 10 09 08
Table of Contents
Chapter 1:
Meet Sylvia Earle . . . . . . . . . . . . . . . . . . . . . 3
Chapter 2:
Creatures of the Midnight Zone . . . . . . . . . 6
Chapter 3:
Earle’s Mission Continues . . . . . . . . . . . . . 12
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Why do people study the deep ocean? What creatures live
in these deep waters? Sylvia Earle has spent her life trying
to answer these questions. Earle is a famous oceanographer,
or scientist who studies the ocean. For over 40 years,
she has studied ocean life. She’s also explored some of its
deepest parts.
Chapter 1
Meet Sylvia Earle
Sylvia Earle grew up on a farm in New Jersey. As a
little girl, she was fascinated by the wildlife around her
home. When Earle was 13, her family moved to Florida,
near the Gulf of Mexico. There, Earle found a whole
new world to explore. She loved to examine starfish, sea
urchins, and other sea creatures.
Sylvia Earle, ocean explorer
3
Earle was a great student, but her parents could not
afford to pay for college. She was able to attend Florida
State University on a scholarship. She worked in college
laboratories to earn money.
Earle learned to scuba dive while in college. She used
this skill to study sea life up close. In 1964, a group of
scientists invited her on a trip to the Indian Ocean. At the
time, it was unusual for women to go on scientific trips.
Over the next few years, she went on more research trips.
Then, in 1970, Earle led a team of women scientists on
a special trip. The participants spent two weeks together.
They lived and worked in a lab that was 50 feet underwater!
A New Underwater Record
During the 1970s, Earle kept
exploring the world’s oceans. In the
South Pacific, she explored sunken
warships from Japan. The
ships were covered with sea
creatures. Later, Earle spent
three months at sea. She
followed sperm whales as
they swam long distances.
Earle helped make a film
about the whales’ journey.
4
Earle wears scuba
gear for some dives.
In 1979, Earle did something no one had done before.
Picture what you might see 1,250 feet below the ocean’s
surface. That’s how far down Earle was. She was walking
on the ocean floor off the coast of Hawaii. She was on
her own. There was no breathing line to help her, just her
scuba tank. No one has walked deeper in the ocean (except
when attached to a special line) since. Earle had set a
record for the deepest sea walk ever!
Sylvia Earle prepares for a dive.
5
Chapter 2
Creatures of the Midnight Zone
Scientists once thought that few creatures lived on
the ocean floor. But Earle found many strange creatures
during her deep-sea dives. She saw fish with glowing spots
under their eyes. She found bright red crabs and squid
with huge eyes.
Earle’s dives earned her the nickname, “Her Deepness.”
6
Earle decided to study deep-sea creatures in new
ways. In the 1980s, she helped design a submarine called
Deep Rover. The sub only carried two people, but it was
very durable. It could travel 3,300 feet below the ocean’s
surface. Earle used it for the deepest dive ever made by
a person alone.
Earle’s research has helped answer questions about
deep-sea creatures. One of these is how do deep-sea
creatures survive?
To understand this question, let’s first look at the
ocean itself. Think of the ocean as having three zones,
or levels. These three zones are based on how far down
into the ocean sunlight can reach.
Most plants and animals live in the top zone, the
Sunlight Zone. Below that is the Twilight Zone. Some
sunlight reaches this middle zone. But it’s not enough for
ocean plants to grow.
About 90 percent of the ocean lies in the bottom
zone, the Midnight Zone. Here the water is dark and
frigid. Even so, many sea animals make their home in the
Midnight Zone.
7
The Three Ocean Zones
0 feet
Sunlight Zone
sharks, whales,
seals, most fish
Twilight Zone
squid, octopus,
jellyfish, many types
of glowing fish
Midnight Zone
bacteria, eels,
some types
of shrimp
600 feet
3,000 feet
9,000 feet
8
Deep Ocean Hot Springs
Scientists have deduced how deep-sea creatures live in
the Midnight Zone. One way they survive is by living near
hot springs. Here is how hot springs form:
1) Cold ocean water flows into cracks on the
ocean floor.
2) The water is heated up in these cracks.
3) The warmer water flows back into the ocean,
creating a hot spring.
The water from hot springs is full of minerals. Many
deep-sea creatures, such as giant tube worms, can live in or
near hot springs. They depend on the warmer water and
its minerals.
Hot springs allow many
deep-sea creatures to
survive in the cold water.
9
Tube Worms and Bacteria
Young tube worms are about the size of small seeds.
Ocean currents carry them to hot springs on the ocean
floor. There, the worms form a partnership with a very
tiny deep-sea creature.
We often think of bacteria as germs that can make us
sick. But for tube worms, deep-sea bacteria are helpers.
The tube worms swallow the bacteria. Then the bacteria
live inside the worms. In turn, the bacteria change
chemicals from the hot springs into real food for the worms.
Scientists don’t know how tube worms and bacteria
became partners. But they have affirmed that their
relationship works well. The worms provide a good home
for the bacteria. As the worms grow, their mouths, eyes,
and stomachs disappear.
The bacteria become their
only way to get food. Tube
worms can grow up to
eight feet long. So, each
worm has room for
billions of bacteria!
Tube worms are often
found in the Pacific Ocean.
10
The Spookfish and the Coffinfish
Deep-sea creatures have other ways to survive, too.
For example, the Pacific spookfish has a soft body and a
long nose. It feeds on tiny shrimp. These shrimp hide in
the deep ocean floor. The spookfish uses its nose to search
for the shrimp. It can even detect a shrimp’s pulse. That’s
like having a metal detector in your nose!
Coffinfish, on the other hand, have short fins. These
fins work like legs, so they can walk on the ocean floor. A
coffinfish can also shrink its lungs. This lets it swallow a lot
of water. The water makes the coffinfish look bigger. This
trick helps scare off predators.
This special diving suit helps
Earle explore the deep ocean.
11
Chapter 3
Earle’s Mission Continues
Today, Sylvia Earle works for the National
Geographic Society. In her latest role, she tells people
about the wonders of the deep sea. But she also reminds
them about the dangers that oceans face.
Earle is very concerned about global warming.
Pollution is the main cause of global warming. Because of
global warming, ocean levels can rise and damage ocean
life. Overfishing is another problem that worries Earle.
Some fishing boats catch too many fish. As a result, some
kinds of fish may die out completely.
Earle believes that water is the key to life on Earth.
When oceans are damaged, humans’ lives are affected as
well. After all, two-thirds of Earth’s surface is covered
by oceans.
Oceans and Our Future
Oceans are part of our history. They also tell us about
our planet’s future. Earle urges people to help save the
oceans. We can do this by cleaning up beaches. We can
also help by cutting down pollution. Earle wants future
scientists — maybe you — to keep studying the oceans.
12
Earle has seen the
amazing world down there.
But there is still much to
be discovered. Other sea
creatures may exist that we
haven’t found yet. As many
as 30 million kinds of sea life
may still be undiscovered!
Perhaps some day
future scientists will live
on the ocean floor. After
all, astronauts can now live
in space stations. Until
then, Sylvia Earle will keep
studying the sea. She’s doing
her best to help unlock the
secrets of the deep ocean!
Future scientists may discover
more of the ocean’s secrets.
13
Index
C
O
coffinfish, 11
ocean zones, 7, 8, 9
D
Deep Rover
and Sylvia Earle, 5, 7
P
E
pollution, 12
Earle, Sylvia
and college, 4
in Florida, 3, 4
with National Geographic
Society, 12
in New Jersey, 3,
and scuba diving, 4–5
G
global warming, 12
H
hot springs
and ocean floor, 9
and tube worms, 9–10
14
overfishing, 12
Pacific spookfish, 11
T
tube worms
and hot springs, 9–10
relationship with bacteria, 10
Responding
TARGET SKILL Main Ideas and Details
What details from the book explain why Sylvia
Earle is called an explorer? Copy and add details
to the diagram below.
Detail: ?
Detail: ?
Sylvia Earle is
an important
explorer.
She walked on
the ocean floor.
Detail: ?
Write About It
Text to World Some ocean areas are protected.
Have you visited a place that needs to be
protected? Write a paragraph about this place
and tell why it should be protected.
15
TARGET VOCABULARY
affirmed
expanse
culmination
frigid
deduced
participants
durable
prime
equivalent
sacrificed
TARGET SKILL Main Ideas and Details Identify
a topic’s important ideas and supporting details.
TARGET STRATEGY Monitor/Clarify As you read,
notice what isn’t making sense. Find ways to figure
out the parts that are confusing.
GENRE Biography tells about events in a person’s life,
written by another person.
Write About It
In a famous quotation, Aung San Suu Kyi said,
“Please use your freedom to promote ours.”
What freedoms do you value most? Why? Write
a letter to the editor of a Burmese newspaper
explaining the freedoms you have and why they
are important to you.
16
Level: T
DRA: 44
Genre:
Biography
Strategy:
Monitor/Clarify
Skill:
Main Ideas and Details
Word Count: 1,370
6.3.13
HOUGHTON MIFFLIN
Online Leveled Books
1032947
H O UG H T O N M IF F L IN