41 L5-All About Islands

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Oxford Read and Discover level 5 All About Islands by James Styring

Introduction An island can be very small, or it can be big, with mountains, lakes, roads, and cities. Some islands are hot, but others are covered with ice. Some islands have animals and plants that don't live anywhere else. Only about 10% of people live on islands. Do you live on an island? What islands do you know? What is the biggest island? Do you know any of these islands? Discover! Now read and discover more about islands around the world!

Chapter 1 What Is an Island? An island is a piece of land with water all around it. There are many different types of island. Where Are Islands? Less than 30% of Earth's surface is land— there are seven continents and thousands of islands. Some islands are in the middle of an ocean, and others are near the mainland. Many islands are so small that you can't see them on this map. How Do Islands Form? Islands can form in a lot of different ways. Some islands formed a long time ago. About 20,000 years ago, Earth was very, very cold. Lots of water from the oceans froze into ice, and the sea level went down everywhere. Later, Earth became warmer and a lot of the ice melted, and the sea level went up. Places that were valleys and mountains 20,000 years ago became seas and islands. Sometimes, land can move away from the mainland to form an island. It takes thousands of years for islands to form in this way.

Volcanoes under the ocean erupt and the lava can form volcanic islands. In 2009, a new volcanic island formed in the Pacific Ocean, near Tonga. Sometimes, waves move the sand at the bottom of the ocean to form islands. In warm oceans, coral grows to form coral islands. Another way is when rivers carry rainwater with small pieces of soil, rocks, and plants. When the water in a river goes slowly, these things in the water fall to the bottom and they can build up and form islands in the river. The Mekong River in Asia has a lot of islands that are made in this way. Amazing Species The animals and plants on some islands grow in different ways from the species on the mainland. Some species live on only one island and nowhere else on Earth. Hispaniolan solenodons live on one island called Hispaniola, in the Caribbean Sea. Solenodons are about 50 centimeters long. They have a long nose and they are the only mammal with poison in their teeth. They use their nose and teeth to hunt insects and other small animals. Hispaniolan solenodons lived at the time of the dinosaurs, 65 million years ago! The solenodons are now in danger because people are cutting down the forests where they live, and dogs are hunting them, too. If we don't protect them, the last solenodons will die and the species will become extinct.

Chapter 2 Volcanic Islands When volcanoes erupt, hot gases, ash, and lava fly into the air. When a volcano under the ocean erupts, the water cools the lava and it becomes rock. After lots of eruptions, the lava can form a volcanic island. Active Volcanic Islands There are thousands of volcanic islands, and some have active volcanoes. Mount Fuji on Honshu Island in Japan is an active volcano, but it hasn't erupted for more than 300 years. The volcano on Stromboli Island, in the Mediterranean Sea, erupts about every two hours! Some of the Canary Islands, in the Atlantic Ocean, have black beaches. This is because the lava from volcanoes forms a black rock when it cools. The wind and waves have changed the rock into sand. Discover! Hawaii is an active volcanic island in the Pacific Ocean. It's getting bigger every year because of the lava from its volcanoes. Hot Rock The underground rock on volcanic islands is often very hot. When underground water meets hot volcanic rock, the water boils. Some of the hot water evaporates into steam, and the steam pushes the hot water up into the air. When this happens, the hot water is called a geyser. Iceland is a volcanic island with a lot of geysers. Iceland is cold, but even in winter, there are hot water pools where people can swim. Plants grow well in the warm ground near the geysers. Discover! Birds have to keep their eggs warm. Most birds sit on their eggs, but incubator birds on some volcanic islands leave their eggs in warm volcanic ash.