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Animal life






 

Can a platypus receive electric signals?

What was homeland of kangaroos?

What animal graces Australia's coat of arms?

Australia has 500, 000 species of plants and animals. Its fauna includes 70% of world's mar­supials: kangaroos, possums, koalas and wombats. Placentals include native dog Dingo. The Koala is one of the most loved animals in Australia. It is a marsupial mammal. They are very fussy eaters, feeding on eucalyptus leaves. Koalas seldom drink. The koala sleeps in a fork of a tree for most of the day. It moves and feeds at night. Koalas leave up to 12-15 years. Emu is a flightless bird about 1, 8 m tall closely related to the ostrich. It graces the coat of arms.

Platypus /Flat Foot/ is web-footed, duck build, egg-laying, venomous Australian mammal. Platy­pus lives 12 years. It is about 45 cm long. It has thick blackish brown fur, a flat bill like that of a duck, no lips, and a long flat tail. Adult male weights over 2 kg. It lays eggs but nurses its young. Its snout /big nose/ is not only for collecting food underwater. Platypus does not use its eyes or ears underwater. It can receive electric signals, giving the mammal a sixth sense that helps it " see" underwater.

The platypus is the only known creature with separate aquatic and terrestrial sensory systems. Un­der water it closes eyes, ears and nostrils.. Scientists did not know what guides the platypus underwater. The answer came in 1986. The platypus is attracted to a battery. There are pores at the bill's sides with nerve endings responsive only to electric currents. The platypuses are very good at pinpointing a source of low-voltage emissions. Only one other mammal, the echidna, has electroreceptors.

The platypus swimming technique is also its own. Unlike other aquatic animals it pushes through water wit front feet. A platypus can drive in spurs and release poison.

They lived long before the Age of Mammals. Platypuses thermoregulate as well as any aquatic mammal. The feeding platypus stays underwater for a minute or so, gathering prey into cheek pouches. It feeds underwater at night, spends much of its time hidden in underground borrows. It is easily stressed to death in captivity. Just one captive egg has been successfully hatched.

We like to think of Australia as the " lucky country". When it comes to the wondrous kangaroos, there is no disputing it. Kangaroos came from North America across Antarctica, in that far-past age when the continents were together.

In the catalog of earth's more curious creatures, few are as wondrous as the kangaroos. They out­class most of the animal kingdom in the long and high jump, boxing and karate. Born die size of a large bean, they can grow taller than a man. They rise their young in body pouches. And in matters of reproduc­tion hold a hidden ace: an expectant female can retain an embryo in ready reserve for months, until all con­ditions are right for its continued development.

Of 250 species of marsupials, some 170 of them including wombats, bandicoots and kangaroos-live only in Australia. Among marsupials, grey and red kangaroos are the largest. Males / boomers/ may stand over 2 meters tall and weigh close to 100 kg. These superb animals cruise at 27kmh. If need arises they can accelerate twice the speed. While grey excel at high jumping, reds take longhop honors. A red graces Australia's coat of arms.

Though timid by nature, boomers make powerful adversaries. Australians traditionally hunted them with huge, specially trained dogs. If water is nearby, the cornered boomer may grab the dog with the forepaws and hold it underwater until it drowns..

The animal's heavy tail, long prized for soup and meat, does more than go along for the ride. On the run it acts as a counterbalance, at a standstill it serves as a sort of stool.

The dominant male in any group fathers most of the offspring with no further responsibility. It's the non-liberated mother roo who must rear, shelter and feed his progeny.

Nocturnal b y nature, they prefer to bed down by day in tall grasses or under the shade of eucalyp­tus trees. Some kangaroos reach the old age of 20, but normal age is 7 years. Eagles, pythons, and goanna lizards pick off small ones: man and din go dogs kill adults. But the most devastating enemy is drought.

Aborigines had been hunting kangaroos for food and skins for uncounted centuries. James Cook, the first European, to reach eastern shores shot a grey while beached for repairs. Arrival of the first Euro­peans stepped up the slaughter until sheep ranchers began altering the environment; Here man proved both friend and foe. Today, every state in Australia has adopted a systemt hat permits controlled destruction of the animals. How to protect the roos? Kangaroos show no respect for boundaries. Several kangaroos are now rare. Clearing the land for grazing spelled their doom.

 


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