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Home , Atlas Mountains, Great Rift Valley, Rift Valley lakes, Saharan Atlas, Tell Atlas

Suggested levels for Guided Reading, DRA,™ Lexile,® and Reading Recovery™ are provided in the Pearson Scott Foresman Leveling Guide. ’sAfrica’s ChangingChanging GeographyGeography

Comprehension Genre Text Features Skills and Strategy Expository • Cause and Effect • Captions nonfi ction • Graphic Sources • Maps • Graphic Organizer • Glossary

Scott Foresman Reading Street 6.5.3 ì<(sk$m)=bdgfjj

113659_CVR_FSD.indd3659_CVR_FSD.indd A-BA-B 110/11/050/11/05 8:12:498:12:49 PMPM Vocabulary Reader Response

densest 1. What caused the formation of Mount Kilimanjaro? 2. Copy the table below on a separate sheet of paper. In the eaves right-handAfrica’s column, list the Changing geographic features of Africa that you read about in this book. In the left-hand column, expanse list the geologicGeography or climate changes that caused the geologic feature. List as many features as you can.

moisture Cause Geographic Feature ventured

Word count: 2,832

3. Read the definition of the word eaves in the glossary. Why did the writer of this book use the word on page 12 in connection with the Great Escarpment? 4. Which of the geographic features described in this book would you most like to visit? Why?

by Lillian Duggan

Note: The total word count includes words in the running text and headings only. Numerals and words in chapter titles, captions, labels, diagrams, charts, graphs, Editorial Offices: Glenview, Illinois • Parsippany, New Jersey • New York, New York sidebars, and extra features are not included. Sales Offices: Needham, Massachusetts • Duluth, Georgia • Glenview, Illinois Coppell, Texas • Ontario, California • Mesa, Arizona

113659_CVR_FSD.indd3659_CVR_FSD.indd C-DC-D 113659_001-024_FSD3659_001-024_FSD 1 111/17/0511/25/06//2157/065 5:50:5851:08:291::5008:5289 PMPM Africa You’ve waited a long time for this trip. Finally, the huge liner sets sail from New York City. The Statue of Liberty fades in the distance as the ship heads southeast across the . You try to visualize what awaits you at your final destination, the great of Africa. Africa—where humans took their first steps, where the great pyramids of Egypt rise from the desert, and the ancestral homeland for millions of Americans. With a land area of about 11,724,000 square miles, Africa is more than 2 million square miles larger than . Africa contains many kinds of landforms. On your trip you might visit a tropical rain forest, an arid desert, a grassy savanna, or even a snowcapped mountain peak. In this book, we’ll look at how and climate have shaped the geography you might encounter on a trip to Africa.

ARCTIC OCEAN Every effort has been made to secure permission and provide appropriate credit for photographic material. The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions. North

Unless otherwise acknowledged, all photographs are the property of Scott Foresman, PACIFIC America a division of Pearson Education. OCEAN ATLANTIC AFRICA OCEAN Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd)

Equator South Opener Phil Banko/Corbis; 1 ©Rob C. Nunnington; Gallo Images/Corbis; 10 ©Yann INDIAN Arthus-Bertrand/Corbis; 11 ©Royalty-Free/Corbis; 12 ©Rob C. Nunnington; Gallo America OCEAN ATLANTIC Images/Corbis; 13 ©Richard List/Corbis; 15 (Inset)Phil Banko/Corbis; 16 ©Andrew PACIFIC OCEAN Brown; Ecoscene/Corbis; 17 ©Rob Howard/Corbis; 20 ©Lloyd Cluff/Corbis OCEAN

ISBN: 0-328-13659-X

Copyright © Pearson Education, Inc. Antarctica All Rights Reserved. Printed in China. This publication is protected by Copyright, and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any Africa is located south of Europe, means, electronic, mechanical, photocopying, recording, or likewise. For information between the Atlantic and Indian . regarding permission(s), write to: Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.

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113659_001-024_FSD3659_001-024_FSD 2 44/6/06/6/06 22:44:45:44:45 PMPM 113659_001-024_FSD3659_001-024_FSD 3 110/11/050/11/05 8:15:128:15:12 PMPM Geographical Features On a trip to Africa, you could visit the world’s longest river as well as its largest desert. The River, in eastern Africa, is more than 4,000 miles long! And the huge, dry EUROPE expanse of the spans most of the northern part of

the continent. ATLANTIC M EEDITE D I T E R OCEAN R To the south of the Sahara lie the and the s RRANEAN A N E A N S E ASEA ntain savanna. The Sahel is a of dry grassland that ou The Sahara receives little rainfall. The savanna is a large, grassy plain MountainsM that gets more rain than the Sahel. REDR E D S E A Africa also has other deserts, including the Namib and Ahaggar Range Range

the Kalahari in the southern part of the continent.

Nile River NileNile River But Africa is more than a land of dry deserts and River Nile Djouf A F R I C A grasslands. It is also home to tropical rain forests. The Basin Chad major rain forests sit on the equator. They are home to Basin Basin A d e n hundreds of species of both and life. GulfG u l f oof f Aden Sometimes geographers call Africa the “ continent.” That’s because a huge plateau covers most of Africa. In fact, in much of your trip through Africa, you Congo would be at least 1,000 feet above sea level. Within the plateau are huge basins, or depressions. Equator Basin Mt. These basins—the Djouf, Chad, Sudan, Congo, and Mt. Kilimanjaro Kalahari—are each more than 625 miles across. Each INDIANI N D I A N OCEAN basin, except the Chad, is home to a complex river system. ATLANTIC Africa also has several mountain ranges, including OCEAN the in the northwest, the Ahaggar Kalahari Mountains in the Sahara, and the Range Basin in the south. Most of Africa’s mountains are volcanic, including Mount Kilimanjaro, Africa’s highest mountain, at 19,340 feet. As you travel through Africa, you might wonder how all these geographic features came to be. Read on to find out. Drakensberg RangeRange Africa’s geography varies greatly from region to region.

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113659_001-024_FSD3659_001-024_FSD 4 110/11/050/11/05 8:15:138:15:13 PMPM 13659_001-024_FSD 5 11/3/05 11:49:49 AM PPangaeaa n g a e a Around 160 million years ago, Pangaea began to break up. Gradually, , Antarctica, Australia, India, Iran, and broke away from Africa and Arabia. The island of also split off from Gondwanaland at that time. Then Arabia began to break away from the eastern side of Africa. This created the and the , leaving only a small piece of land connecting Africa to Asia. This piece of land was called the Isthmus of Suez, and it later became the site of the Suez Canal. Built in 1869, the Suez Canal connects the LLaurasiaaurasia with the Red Sea. The crack that created the Red Sea also extends on land. On land this crack, or , created great rift valleys known as the System.

GGondwanalandondwanaland

th r a EurasiaEurasia NorthNo ic er AmericaAm How Africa Was Formed AfricaAfrica Scientists believe that all seven of ’s IIndiandia h used to be part of one supercontinent named Pangaea. SouthSout rica Pangaea had two major sections: Laurasia was made AmericaAme up of North America, Europe, and northern Asia. Gondwanaland included Antarctica, Australia, southern Asia, South America, and Africa. It seems almost unbelievable, but scientists have good reason to think that Pangaea really existed. They have found evidence that all the continents were once connected; layers of rock found underground in northern Africa closely resemble rocks found in Europe. The Atlas Mountains in northern Africa are an extension of the in . And, if you look at a globe, you can see that the coastlines of eastern South America and western Africa fit together, like puzzle pieces.

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113659_001-024_FSD3659_001-024_FSD 6 110/11/050/11/05 8:15:348:15:34 PMPM 113659_001-024_FSD3659_001-024_FSD 7 110/11/050/11/05 8:15:368:15:36 PMPM The East African Rift System At a length of 4,000 miles, the East African Rift System is one of the longest on Earth. It begins in in southwestern Asia and slices south through eastern A F R I C A Africa, ending in . The main branch of the East African Rift System is the Great Rift , or Eastern Rift Valley. It has an average width of 30 miles, but at its widest point the valley spans The East African Rift System 60 miles. To the west of the lies the Western Rift Valley. If you were to climb up from either valley, you would face slopes with an average height of 2,000–3,000 feet. In Great Rift Valley some places, cliffs drop more than 6,000 feet to the valley floor! The widest space between the two rifts contains Lake . When the two rifts first formed, the edges were pushed up and out. A depression formed between them. SOMALIA It filled with water and became . It is the world’s second largest freshwater lake, but Lake Victoria is far less deep than the other . Some sections of the rifts have filled with water, forming deep lakes. The largest is . With a length of about 420 miles, it is the longest freshwater lake in the world. It also has a maximum depth of 4,800 KENYA feet—that’s nearly a mile. Equator The formation of the East African Rift System also Lake Mt. Kenya caused magma, or molten rock, to rise from below Earth’s Victoria surface. The rising magma formed several volcanoes Ngorongoro that are found along the rift, two of which are Mount Crater Mt. Kilimanjaro Kilimanjaro and Mount Kenya. 

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113659_001-024_FSD3659_001-024_FSD 8 110/11/050/11/05 8:15:368:15:36 PMPM 113659_001-024_FSD3659_001-024_FSD 9 110/11/050/11/05 8:15:378:15:37 PMPM Mount Kilimanjaro Ngorongoro Crater Africa’s tallest mountain looks as though it arose from To the west of Mount Kilimanjaro, along the Great nowhere. Where did this lone mountain come from? Rift Valley, sits Ngorongoro. Scientists believe that the Mount Kilimanjaro, like other volcanoes, was formed by crater was formed about 2.5 million years ago, after the the gradual buildup of magma that rose to the surface, cone of an extinct collapsed. This collapse left cooled, and turned to rock. behind a flat area surrounded by a raised rim. The crater Perhaps you might miss the cool winter weather back measures 10–12 miles across and has an area of 102 home as you travel through Africa. No need to worry— square miles. The rim rises 2,000 feet above the crater’s just climb the mountain. Even though Kilimanjaro lies floor. only two hundred miles north of the equator, it is so high After millions of years, the crater floor is now open that it is topped with snow. grassland. It is home to elephants, black rhinoceroses, Kilimanjaro is actually made up of three volcanoes— leopards, buffalo, zebras, warthogs, wildebeests, and Kibo, Shira, and Mawenzi. Together, they form a single gazelles. The world’s densest population of lives mountain that is more than fifty miles wide. Kibo is the within the crater, as well. highest cone of the three, and it is the only one that still Ngorongoro Crater also holds a lake—. occasionally spits hot gases. Because of the volcanic ash deposited on the lakebed, Many and live on Mount Kilimanjaro. Lake Magadi’s water is alkaline. If you should visit the Elephants, buffalo, eland (a type of antelope), several lake, you will see large flocks of pink flamingoes feeding species of monkeys, and many types of birds are found in there. its forests. Ngorongoro Crater is home to the densest population of lions in the world.

The Europeans who first saw Mount Kilimanjaro in the 1800s were shocked to find a snowcapped mountain so close to the equator. 10 11

113659_001-024_FSD3659_001-024_FSD 1010 110/11/050/11/05 8:15:388:15:38 PMPM 113659_001-024_FSD3659_001-024_FSD 1111 110/11/050/11/05 8:15:428:15:42 PMPM The Great Escarpment The Atlas Mountains After the rest of Pangaea separated from Africa, crust If you were to make your way back from the Great movements forced part of to lift. The lift Escarpment in southern Africa to the northwestern part created an elevation known as the Great Escarpment. An of the continent, you could visit the Atlas Mountains. escarpment is a long cliff or steep slope separating two, The Atlas Mountains are actually two mountain chains more level, surfaces—one at a lower elevation than the that run parallel to each other. The two chains, or ranges, other. developed in different ways and at different times. The Great Escarpment is where Africa’s plateau ends The is older than its sister mountain in the southern part of the continent. In addition, rivers range, the . The Saharan Atlas was formed more running through some sections of the Great Escarpment than 66.4 million years ago, as a result of the folding, or have carved gorges into the rock. bending, of Earth’s crust. Like the Great Escarpment, the If you should decide to visit the Great Escarpment, Saharan Atlas is part of the vast plateau that makes up watch your step . . . it’s a long way down! much of Africa. About 2,000 years ago, the San, or Bushmen, lived The Tell Atlas was formed over time between 66.4 in the area of the Great Escarpment and other parts of and 1.6 millions years ago. First, a group of bent layers South Africa. Their rock paintings have been found on of rock, known as folds, raised up over a valley. Then, the eaves of hills in the Great Escarpment. sheets of sandstone and clay deposits slid down from the north over the rim of the folds, building up the . Movement beneath the Tell Atlas indicates that the range is still forming today.

The Atlas Mountains separate At the top of the Great the Sahara from the shores of Escarpment is the edge the Mediterranean. of the plateau that covers much of Africa. 12 13

113659_001-024_FSD3659_001-024_FSD 1212 110/11/050/11/05 8:15:458:15:45 PMPM 113659_001-024_FSD3659_001-024_FSD 1313 110/11/050/11/05 8:15:498:15:49 PMPM The Sahara If you are the adventurous type, you might turn EUROPE south and visit the largest desert in the world, the ATLANTIC MEDITERRANEANM E D I T E R SEA Sahara. It covers a total area of three-and-a-half million OCEAN R A N E A N ASIA S E A square miles—almost the size of the . It lies between the Atlas Mountains to the north and the Sahel ATLAATLASS MOUNTAINSMOUNTAINS ins to the south, and it stretches from the Atlantic Ocean to REDR ggar Mounta E D S E A AhaggarAha Mountains the Red Sea. The Sahara varies in distance north to south, Mt. Koussi S E A ranging between 800 and 1,200 miles. THET H E S ASAHARA H A R A Even though the Sahara is famous for its large NigNiger

of sand, only about one-fourth of the great desert is er A d e n covered with sand . Other parts consist of bare, River GulfG u l f oof f Aden rocky, or gravelly plains—or even mountains. In fact Sahel A F R I C A mountains seem to rise out of nowhere. One of these is Mount Koussi, which, at 11,204 feet, is the highest point in the Sahara. Equator Like all deserts, the Sahara is very dry. Some INDIANI N D I A N receive as little as one-quarter of an inch of rainfall in an OCEAN entire year, while others may not have rain for several ATLANTIC years. But the Sahara is not completely dry. Scattered OCEAN oases, areas where it is wet enough to grow plants, get up to 16 inches of rain per year. An oasis is a welcome sight to thirsty travelers who have ventured across the Sahara. In spite of the dry conditions and difficult terrain, two and a half million people live in the Sahara. That is about one person per square mile.

Some oases in the Sahara are located in depressions, or low-lying areas.

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113659_001-024_FSD3659_001-024_FSD 1414 110/11/050/11/05 8:15:538:15:53 PMPM 13659_001-024_FSD 15 10/11/05 8:15:54 PM The Sahara’s Green Past The Sahara Today You might have a hard time imagining the Sahara Even today, the Sahara is constantly changing, and as being anything other than a desert. But in fact, the the force of wind is a major factor. Strong winds that Sahara did not become a desert until about five million last for days carry sand, soil, and dust for miles. When years ago. Since then, the Saharan climate has changed these substances are moved from one place to another, from time to time. At times the desert has been more the landscape changes in both places. humid, and at other times it has been drier. In the Sahara, winds move in regular patterns. In the Between 5,000 and 10,000 years ago, the Sahara north, the wind shifts the sand from west to east. experienced its most recent wet period. Ancient rock In the south, the sand is shifted from east to west. art showing images of hippopotamuses indicates that Besides causing the sand to shift, winds in the Sahara the Sahara must have been wet year-round at one time, also mold rock formations. In rocky sections of the because hippos need water constantly. Sahara, the wind sculpts yardangs. Yardangs are large The Sahara became wet and green because of the sections of rock that are carved by the wind into shapes shifting of the African monsoon. A monsoon is a wind that are wider at the top than at the bottom. If you that can bring tremendous rainfall. Monsoons move both were to visit the Sahara, you would find yardangs mainly north and south. The movement is affected by the tilt of in the eastern part of the desert. Earth and the nearness of Earth to the sun. Other changes taking place in the Sahara and the When the tilts sharply toward Sahel to the south threaten the people who live there. the sun and Earth is closest to the sun, Earth receives For centuries, farmers have grazed their animals on increased amounts of sunlight. This extra sunlight grasses that grow in the Sahel. can cause the African monsoon to shift to the north, However, since the 1960s, the average rainfall in dropping rain on dry regions like the Sahara. the region has declined. Today, the Sahara appears to About 10,000 years ago, the African monsoon moved be moving south into the Sahel, and Sahel farmers into the Sahara, changing the environment of the desert. are finding less food for their animals. Some scientists Then, 5,000 years later, the monsoon moved back toward believe that overgrazing is the cause of the drying the south again. After the land dried, it could no longer up of the Sahel. Others feel that an increasingly dry hold moisture, even when it did rain. regional climate is to blame. However the last wet period in the Sahara left large beneath the barren landscape. Aquifers are areas of fresh water found underground among rock, sand, or gravel. Today, people mine these aquifers to provide water for farming and drinking.

This yardang in the Sahara was formed by wind.

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113659_001-024_FSD3659_001-024_FSD 1616 110/11/050/11/05 8:16:038:16:03 PMPM 113659_001-024_FSD3659_001-024_FSD 1717 110/11/050/11/05 8:16:038:16:03 PMPM The Nile River The Nile River is 4,132 miles long—the longest river in the world. It begins south of the equator and flows north to the Mediterranean Sea. The Nile has more than one source. The three main EUROPE streams that feed the Nile are the Blue Nile, the Atbara, ATLANTIC and the White Nile. However, Lake Victoria is considered OCEAN MEDITERRANEANM E D I T E R R A N E A N S E A SEA ASIA to be the main source of water for the Nile River. The Nile River basin is the area of land that drains into Nile River River the Nile. It makes up about one-tenth of the total area of the continent. Several important ancient civilizations NileN i l e R i vRiver e r B a s i nBasin REDR E D S E A SEA developed in this region, because there was enough water to farm along the banks, and the river was a good source of transportation. A F R I C A AtbaAtbarara Rive Riverr Scientists believe that 30 million years ago, the Gulf of of Aden Aden Nile was much shorter. They are not sure how the Nile Blue Nile Ni leRiver River reached its current length. According to one theory,

water from a part of eastern Africa once drained into White Nile River Lake Victoria. Around 25,000 years ago, some of this water started to shift to a lake to the north. Gradually, Equator material in the water began to collect in that northern Lake Victoria INDIAN lake, causing the lake’s water level to rise. The lake OCEAN began to overflow. The overflow water drained farther ATLANTIC to the north and formed its own riverbed. This riverbed OCEAN linked the southern and northern sections of the Nile and lengthened the river.

Many people have settled along the Nile River valley because it is fertile for at least part of the year.

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113659_001-024_FSD3659_001-024_FSD 1818 110/11/050/11/05 8:16:058:16:05 PMPM 13659_001-024_FSD 19 10/11/05 8:16:06 PM The tropical climate in the Nile River valley has played Summary an important role in its geography and agriculture. In Your imaginary trip through Africa has come to an the past, annual floods during the summer caused the end. Think about what you have learned about the water level of the river to rise and overflow its banks. In geologic and climatic causes of change that affect Africa’s general, people who lived along the Nile welcomed the geography: floods. The floods brought moisture and healthy soil to • Africa has undergone great changes since it first broke an area that otherwise could not be farmed. off millions of years ago from the supercontinent, But the floods could also be dangerous. For centuries, Pangaea. the timing of the flooding of the Nile and the amount • Geologic forces are responsible for the formation of of water it would bring could not be predicted. In some huge landforms and entire regions, such as Mount seasons, the floods were so severe that they damaged Kilimanjaro, the Great Escarpment, and Lake Victoria. crops growing near the river. There were also occasional • Africa’s climate, for better or worse, has had a droughts. dramatic effect on the Sahara, the Sahel, and the Nile In 1970, the Aswan High was built in Egypt. River valley. The dam makes it possible to control the amount of • All of these changes, both past and present, are water that floods the Nile River in most of Egypt, so that important to the people of Africa, as they try to farming can be more successful. exploit the resources of that great continent.

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113659_001-024_FSD3659_001-024_FSD 2020 110/11/050/11/05 8:16:158:16:15 PMPM 113659_001-024_FSD3659_001-024_FSD 2121 110/11/050/11/05 8:16:278:16:27 PMPM GlossaryVocabulary Reader Response

densestdensest adj. the most of moisture n. water in liquid 1. What caused the formation of Mount Kilimanjaro? something in a given area or vapor form 2. Copy the table below on a separate sheet of paper. In the eaveseaves n. edges of a roof ventured v. to have done right-hand column, list the geographic features of Africa that extend beyond the something regardless of the that you read about in this book. In the left-hand column, buildingexpanse risk involved list the geologic or climate changes that caused the expanse n. a large area of geologic feature. List as many features as you can. something spread out moisture Cause Geographic Feature ventured

Word count: 2,832

3. Read the definition of the word eaves in the glossary. Why did the writer of this book use the word on page 12 in connection with the Great Escarpment? 4. Which of the geographic features described in this book would you most like to visit? Why?

Note: The total word count includes words in the running text and headings only. Numerals and words in chapter titles, captions, labels, diagrams, charts, graphs, sidebars, and extra features are not included.

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113659_CVR_FSD.indd13659_001-024_FSD3665599__C0V0R1_-F0S2D4._inFdSDd C-DC22242-24D 110/11/050/11/05 8:16:368:16:378:16:367 PMPM 113659_001-024_FSD3659_001-024_FSD 2323 110/11/0511/25/060//2151/0/60 5 5:50:585 : 58:16:3780::1568: PMP3M7 PMPM