An elephant has long, curved upper teeth called tusks. They are made of ivory. Elephants use their tusks to dig for food and water and to fight.
Explanation
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Most kinds of cranes live in Asia, Africa, and Europe. Some live in North America. Several kinds of cranes are endangered today because their wetland homes have been destroyed. The whooping crane of North America is one of the rarest birds in the world. Only a few hundred of these elegant birds are left.
Until a few hundred years ago, species became scarce or died out because of natural causes. For example, there may have been a major climate change. Today, however, species become endangered mostly because of human activity. The main reasons are habitat destruction, wildlife trade, overhunting, and competition with domestic animals and animals brought into their habitat from elsewher
The largest turtle is the leatherback turtle. It grows from 1.2 to 2.4 metres long. The smallest turtle is the bog turtle. It grows only about 10 centimetres long.
The axolotl > is an unusual Mexican salamander. The adult axolotl lives in the water Wild axolotls live in shallow lakes in Mexico City. The growth of Mexico City has damaged most of the areas where axolotls live. They are nearly extinct in the wild.
Scientists call a species endangered if they expect it to die off in less than 20 years unless we find ways to protect it. Some species are small in numbers but not endangered because their population is not going down.
Gorillas have no real enemies except human beings. People hunt gorillas for food, capture them for zoos, and cut down the forests they live in. As a result, the gorilla has become rare in many parts of Africa, and its survival is threatened. Gorillas are among the smartest animals. In the 1970's, scientists taught a gorilla named Koko how to use sign language.
Also, many wild species are protected by CITES—the Convention on International Trade in Endangered Species of Wild Fauna and Flora (“fauna and flora” means animals and plants). This agreement forbids the trade of furs and live animals of endangered species.
Bonobos > are African apes closely related to chimpanzees. Bonobos live in a section of African rain forest south of the Congo River in the Democratic Republic of the Congo. They are also called pygmy chimpanzees
Some animal species that are now extinct in the wild still live in zoos. They live in animal research centres, too. Scientists at these zoos and research centers try to help these animals start new families. They hope that someday these new families can return to the wild. Rare plants are saved by being grown in large gardens called botanical gardens. The seeds are saved in special seed banks for future planting.
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