Kangaroos
By: Francesca Black
The kangaroo is a singular creature. What other animal can jump a distance of 28 feet, or a height of 6 feet? What other animal can hop at speeds of 43 miles per hour? What other animal uses its muscular tail as a third "leg" to help balance and stabilize and holds kickboxing matches to determine breeding rights? There's only one animal that fits this description-the kangaroo.
At the mention of the word kangaroo two words instantly jump into people's minds: pouch and Australia. Indeed, these large marsupials are natives to the land down under. Three species of kangaroos populate the continent: Reds, Eastern Grays, and Western Grays. Since man appeared 50,000 years ago kangaroos have been an important resource to Australia's Indigenous peoples and have been used for food, clothing, and shelter. They are still hunted today, but only under strict government control. Specially adapted for the fragile ecosystem, kangaroos thrive in their home.
Kangaroos are the largest surviving marsupials in the world. A male buck can reach 6 ½ feet tall, and weigh 200 pounds. Female flyers are slightly smaller. Their babies, called joeys, are born at only 31-36 days gestation. (This is developmentally equivalent to a 7 week old human embryo!) At only 0.35 ounces, the joey's forelimbs are developed enough to climb from the birth canal to its mother's pouch, where it attaches to one of four teats. There it stays cuddled up for nine months, transforming from a hairless, pink, bean-sized mite, to an irresistibly furry, doe-eyed darling. Then it will venture out of the security of its pouch for a short adventure before hopping back in. Its mother will feed and protect it another nine months, until her next joey is born. Flyers are perpetually pregnant once they reach maturity. Immediately after giving birth they go into heat. The fertilized embryo will go into a dormant state until the older joey has vacated the pouch. The milk produced by the flyer is specially suited to its growing joey's needs. If she is simultaneously feeding an older and a younger joey, a flyer may produce two different kinds of milk!
The rangeland where kangaroos graze is hot and arid, but kangaroos are suited for their environment. To conserve energy and keep cool kangaroos are crepuscular, meaning that they rest during the day and are most active at twilight hours. They shelter under trees and in caves and rock clefts during the day. Instead of sweating and panting, kangaroos lick themselves all over to cool off. Their long hindquarters have a stretchy tendon and studies have shown that even the kangaroo's breathing is synchronized with their rhythmic leaping. In this way their agile bodies are designed to be fast and energy-efficient, two important qualities that are needed to cover the long distances in search of food and water. Kangaroos are not built for walking, and their legs do not move independently of each other. Because of this they cannot walk backwards. This fact won kangaroos a prominent position on the Australian coat-of-arms, where it symbolized progress and forward movement.
Emma Snow has always adored wild animals. Emma provides content for Wildlife Animals http://www.wildlife-animals.com and Riding Stable http://www.riding-stable.com .
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