The Tasmanian devil is a marsupial – an animal that feeds and carries its young in a pouch. It lives only in Tasmania and was called a devil by the early European settlers because of its fierce appearance and loud screeching.
The devil is the same size as a small dog. It has a large head, a stocky body and a short, thick tail. While the fur is mostly black, there are often white markings on the back and chest. Because the devil is a nocturnal animal (it is active at night), it spends the days in the dense bush and hunts for food after dark.
While it can catch prey the size of a small wallaby the devil often feeds on the bodies of dead sheep and cows from farms. Its very powerful jaws and teeth enable it to eat bones and fur as well as the meat. Farmers are pleased that devils stop the spread of disease by removing the rotting bodies of dead animals. Groups of devils eat together from the same carcass – body of a dead animal – and they are such noisy eaters that they can be heard for several kilometers.
Devils breed in March and the young are born in April. While more are born, only two or three babies survive to live in their mother’s pouch for four months. They move with their mother into a whole or a hollow log until they are ready to live on their own in the bush at the end of December. Devils live until they are seven or eight years old.
Recently adult devils have been affected by cancer. This begins with lumps around the mouth and spreads to the face and neck. Scientists are studying the cancers so they can find out the cause and save the devil population in Tasmania.
Many people imagine the sea-horse to be real horse living in the sea. This is not true at all. The sea-horse is so called because it is a tiny creature with a horse – liked head which lives in the sea.
Sea – horse are found mostly in warm seas. They have a long, flexible tail which is used for wrapping around weeds for support. They swim I upright position, their movements being helped by a rapidly oscillating fin on their back. The male sea – horse lays her eggs in this pouch.
The most remarkable thing about the sea – horse is that part of the process of reproduction is taken over by the male creature. One the female sea – horse has laid her eggs in the male creature’s pouch, she leaves. The hatching of the egg is done by the male fish.
Mating begins with the male and the female sea – horses doing courtship dance. The male and female creatures swim around each other in circles. At the end of the dance, the male appears to bow to its partner; but in actually, the male is banding to pump water from his pouch. Next, the female fish lays eggs into the male’s pouch. About two hundred eggs are laid. The pouch, then close up. The female sea-horse now swims away, leaving the male sea-horse to do hatching.
The eggs are hatched about a month later. The young sea-horses are ejected from the male creature’s pouch by means of muscular contractions.
The sea – horse feeds on tiny fish the creatures sucking them into its month.
For many years, many people believed that the cleverest animals after man were the chimpanzees. Now, however, there is proof that dolphins may be even cleverer than these big apes.
Although a dolphin lives in the sea it is not a fish. It is a mammal. It is in many ways, therefore, like a human being.
Dolphins have a simple language. They are able to talk to one another. It may be possible for man to learn how to talk to dolphins. But this will not be easy because dolphins cannot hear the kind of sounds man can make. If man wants to talk to dolphins, therefore, he will have to make a third language which both he and the dolphins can understand.
Dolphins are also very friendly toward man. They often follow ships. There are many stories about dolphins guiding ships through difficult and dangerous water.
Silkworms live for only two or three days after laying eggs. About 36.000 to 50.000 eggs are laid, and these are carefully stored at the silkworm farm until they are ready to hatch. The eggs hatch into caterpillars, which feed on mulberry leaves. Soon the caterpillars are ready to spin their cocoons. Not all caterpillars can spin silk cocoons. Only the caterpillars of a silkworm moth known as ‘Bombyx mori’ can do such spinning.
This caterpillar has special glands which secrete liquid silk through its lower lip. The liquid produced later hardens to form fine strands. The caterpillar makes its cocoons using these strands. The threads on the outside of the cocoons are rough, while those inside are soft and smooth.
Some fully-spun cocoons are heated. This kills the pupa inside. The cocoons are then put into hot water to loosen the fine threads. Finally, these threads are reeled off the cocoons.
The length of unbroken thread produced by a single cocoon measures about one-and –a-half kilometers. Being twisted together several of these threads make single woven materials.
The white pelican is one of the most successful fish eating birds. The success is largely due to its command hunting behaviour. A group, perhaps two dozens birds, will gather in a curved are some distance offshore, beating the water furiously with their wings, driving the fish before them.
When the water is shallow enough for the birds to reach the fish, the formation breaks up as each bird dip its bill into the water to scoop up its meal. As the bird lifts its head, the water drains from its bill leaving the fish which are then swallowed.
Pelicans are among the oldest group of birds. Fossil of this genus have been founded dating back 40 millions years.
Tiger
The tigers wild animals, to multyply in sumatra. The largest and the most powerful of the “big cats”, the tigers an apex predator and abligate carnivora.
Reaching up to 4 meters in total length and weighing and weighing up to 300kg the tiger’s has naded sharp, moustacheed, with a tail and the tiger to brestfeed.
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