When the Sahara was green: stretch · Grades 4–5

The passage and its 8 questions

Directions: Read the passage carefully. Then answer the questions in full sentences.

• Today, the Sahara is the largest hot desert on Earth. It stretches across North Africa and is almost as big as the whole United States. Much of it is sand, rock and blazing sun. But thousands of years ago, the Sahara looked completely different.
• Between about 11,000 and 5,000 years ago, much of the Sahara was green. Grasslands covered huge areas, and sparkling lakes dotted the land. One lake was so enormous that scientists call it Mega-Chad. Hippos wallowed in rivers, and herds of giraffes and elephants roamed the plains.
• What caused this amazing change? Over thousands of years, Earth slowly wobbles as it spins, and this changes how much sunshine different places receive. Because of the wobble, northern Africa got stronger summer sunshine than it does now. The extra heat made the yearly summer rains, called monsoons, stronger, so more rain fell deep inside the desert. As a result, plants spread, and animals followed.
• How do we know? The people who lived there left clues. They painted and carved pictures on rocks, showing giraffes, cattle and what look like people swimming.
• Scientists have also dug up fish bones, crocodile fossils and bone harpoons in places that are now bone-dry.
• About 5,000 years ago, the sunshine pattern shifted again. The rains grew weaker, the lakes shrank, and the desert slowly returned. Many people and animals moved toward rivers such as the Nile. The rock paintings remain, like postcards from a greener world.
• 1. During what time was much of the Sahara green?
• 2. What text structure does paragraph 3 use? Name two signal words that tell you.
• 3. What effect did stronger monsoons have on the Sahara?
• 4. What does 'bone-dry' mean in paragraph 4?
• 5. Why do you think many people moved toward rivers such as the Nile?
• 6. Copy the sentence that gives evidence that water animals once lived in the Sahara.
• 7. Find a word in the passage that was new or tricky for you. What do you think it means? Which words around it helped you?
• 8. What is the author's purpose: to inform, to entertain or to persuade? Explain.