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A herd of elephants can contain up to several hundred individuals. A male African elephant can reach a mass of 6 tonnes and live for up to 60 years. Elephants walk at 4 to 6 km/h but they can charge at speeds of up to 40km/h.
An elephant's tusks are very long incisor teeth. A tusk can have a mass of 60kg. The elephant uses its tusks to rip bark from trees and to dig up roots. The trunk is very sensitive and has sensory hairs at its end. It can be used to pick up very small objects.

They eat grasses and branches from trees and bushes. Elephants use their long trunks to break off branches and put them in their mouths. During the wet season, elephants eat grasses and leaves, but in the dry season they eat the woody parts of trees and shrubs. An adult elephant needs to eat 150kg of food each day. If the herd feeds for a long time in the same area it can destroy all the trees and bushes, changing forest into grassland.

The elephant also uses its trunk to drink. It sucks water into its trunk and then squirts the water into its mouth. Elephants need to drink between 70dm3 and 90dm3 of water each day.

Fishing Birds

Comorants, Peru © Shirley Burchill

Some sea birds, such as the pelican, swim on the surface of the sea and gather up shoals of fish in their beaks. The lower part of the beak is made of an elastic tissue which acts like a stretchable bag to allow more fish to enter.
Other sea birds dive below the surface to find fish. Some, such as the cormorant, dive directly from the surface. Others dive by plunging into the sea from high in the air. Up to 1000 gannets have been seen diving together when flying over a shoal of fish.

Because these sea birds take fish from different depths in the sea they avoid competing with each other for food.


The giraffe lives in the African open woodland. A male giraffe reaches a height of up to 4,7 metres and can have a mass of 1,9 tonnes. The giraffe can live for up to 25 years in the wild. A giraffe has a long neck and can reach the highest branches of tall trees to eat the leaves.

Although the giraffe has such a long neck it only has 7 vertebrae, the same as in other mammals. The neck vertebrae, however, are each very much longer than those found in other mammals. The giraffe has an excellent eyesight, good hearing and a good sense of smell. Giraffes can run at a speed of 60km/h if they are in danger.

The giraffe has extremely movable lips with sensitive hairs and a long, black tongue which helps it pick off the leaves between the branches. The male giraffe stretches its neck to eat the leaves at the top of the tree. The female giraffe bends her neck slightly and eats from the lower branches.

Giraffes live in herds which move to riverside regions during the dry season. They eat leaves and shoots of trees and shrubs. They will also eat flowers and fruits when they are available. Adult male giraffes need to eat 19kg of food each day, about 1,6% of their body mass.


Gnu, Tanzania © Shirley Burchill

An adult gnu has a mass of 230kg. Gnu live in herds which contain between 50 and 1,000 animals. At the start of the dry season Gnu herds move 250 kilometres north to find grass and water. They move south again in the rainy season. This type of movement involving hundreds of animals is called migration. When herds of gnu migrate to find food there can be as many as 350,000 animals moving together.

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