Transcript of "Pptondesertsandanimals 120628035802-phpapp02"
Introduction to Deserts Deserts are mainly found around the tropic of Cancer and tropic of Capricorn in Northern and Southern Hemispheres respectively. The common definition of desert is a region that receives less than 25cm of rain a year on average. When people think of deserts, the following image comes to their minds : hot and arid land, vast expanses of sand, soil of reddish brown color, a sky of brilliant blue, no or very few plants, cacti, spiny leaves and camel is the only animal that they can think of. The truth is not like that. It is not very common to find sand in a desert, but small rocks, pebbles and loose gravel on the surface layer instead. Only 15% of the world s desert surface is pure sand.Previous
The camel is a large, strong desert animal. Camels can travel great distances •across hot, dry deserts with little food or water. They walk easily on soft sandwhere trucks would get stuck, and carry people and heavy loads to places thathave no roads. Camels also serve the people of the desert in many other ways.The camel carries its own built-in food supply on its back in the form of ahump. The hump is a large lump of fat that provides energy if food is hard to Dromedaryfind.There are two chief kinds of camels: (1) the Arabian camel, also calleddromedary, which has one hump, and (2) the Bactrian camel, which hastwo humps. In the past, hybrids (crossbreeds) of the two species were usedwidely in Asia. These hybrid camels had one extra-long hump and were largerand stronger than either of their parents. Bactrian came l
Mongooses are short-legged animals with pointed noses, small ears,and long, furry tails. The claws are nonretractile, and in most speciesthere are five toes on each foot. The fur is gray to brown and iscommonly grizzled or flecked with lighter gray. Markings, whenpresent, include stripes, dark legs, and pale or ringed tailsMongooseslive in burrows and feed on small mammals, birds, reptiles, eggs, andoccasionally fruit. A number of mongooses, including those of thegenus Herpestes, will attack and kill poisonous snakes. They depend onspeed and agility, darting at the head of the snake and cracking theskull with a powerful bite. They are not immune to venom, as popularlybelieved, nor do they seek and eat an herbal remedy if bitten. .
Rattlesnakes are poisonous snakes that have a rattle on their tail. Incolder areas, this normally solitary snake overwinters in a den withmany other rattlesnakes. These snakes are good swimmers. Rattlers tryto avoid humans.Like all snakes, rattlers are cold-blooded; they are the sametemperature as the environment. They continue to grow all their lives,getting bigger and bigger each year. Their scaly skin glistens but is dry isto the touch. The scales vary from yellow to brown to black, and thereare dark V- or diamond-shaped markings along the back. The snakesmells with its tongue and has two long, hollow fangs that inject arelatively weak venom (poison) into prey. Females give birth to about10 live young, born without a rattle.Back to Animals Gallery
Addax also known as the screw horn antelope, is a criticallyendangered species of antelope that lives in the Sahara desert. As suggestedby its alternative name, this pale antelope has long, twisted horns. It is closelyrelated to theoryx, but differs from other antelopes by having large squareteeth like cattle and lacking the typical facial glands. Although extremely rare inits native habitat due to unregulated hunting, it is quite common incaptivity. They are sometimes hunted as trophies on ranches in the UnitedStates.They are amply suited to live in the deep desert under extreme conditions.Addax can survive without free water almost indefinitely, because they getmoisture from their food and dew that condenses on plants. Scientists believethat the Addax has a special lining in its stomach that stores water in pouchesto use in times of dehydration. They also produce highly concentrated urine toconserve water.
Red KangarooRed kangaroos are large animals with extremely long and powerfulhind legs and feet. Their tail is also long and muscular but their frontlimbs are short. When moving fast they hop on their hind legs, usingtheir tail as a counterbalance, and when moving slowly they use theirtail as an extra limb, taking their weight on their front limbs and tailwhile hopping their hind feet forwards.The Red Kangaroo is mainly active in the cool of the evening or night,and lives alone or in small groups called mobs (although foodshortages can cause them to congregate into larger groups).Membership of these groups is very flexible, and males (boomers) arenot territorial, fighting only after females (flyers) which come intoheat. The largest males are dominant, and control most of thematings..