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الموضوع: The African Animals

  1. #1
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    افتراضي The African Animals










    The African continent is home to a diverse group of animals. Famed for large predators, like lions and cheetahs, its savannahs are also home to a wide variety of grazing animals, as well as elephants, hippos and gorillas. Africa is not just grasslands, however -- there are deserts, snow-capped mountains, forests and jungles, all of which host animals native to those habitats. The colder regions are even home to animals you wouldn't expect to find in Africa, like wolves and penguins.


    If a female rhinoceros is in heat, her urine emits a special chemical called a pheromone, which the male recognizes by smell.

    If her urine does not have this chemical odor, the male wanders off to find another female that might be a possible candidate as a mate.




    The African hippopotamus might look docile but, with sharp tusks and nasty dispositions, they're responsible for more human deaths than African lions. Hippos have even been known to bite off a person's head!







    The Aardvark (Orycteropus afer) is a medium-sized mammal native to Africa. The name comes from the Afrikaans/Dutch for "earth pig" (aarde earth, varken pig), because early settlers from Europe thought it resembled a pig. However, the Aardvark is not closely related to pigs.


    Chew on This: The most distinctive charactristic of aardvarks is their teeth. Instead of having a pulp cavities, aardvark teeth have lots of thin tubes of dentine, each containing pulp and held together by cementum. The teeth have no enamel coating and are worn away and regrow continuously. In adults, the only teeth are the molars at the back of the jaw.





    Appearance:

    The Aardvark is only vaguely pig-like; the body is stout with an arched back; the limbs are of moderate length. The ears are disproportionately long and the tail very thick at the base with a gradual taper. The greatly elongated head is set on a short, thick neck, and at the end of the snout is a disk in which the nostrils open. The mouth is typical of species that feed on termites: small and tubular. The Aardvark has a long, thin, protrusible tongue and elaborate structures supporting a keen sense of smell. The Aardvark is a pale yellowish gray in color, often stained reddish-brown by soil. The coat is thin and the animal's primary protection is its tough skin; the Aardvark has been known to sleep in a recently excavated ant nest, so well does it protect them.





    Aardvark of Africa:

    The Aardvark is distributed across most of sub-Saharan Africa, and although killed by humans both for its flesh and for its teeth (which are used as decorations), does not appear to be threatened.


    Insects for Dinner:



    The Aardvark is nocturnal and a solitary creature that feeds almost exclusively on ants and termites. An Aardvark emerges from its burrow in the late afternoon or shortly after sunset, and forages over a considerable home range, swinging its long nose from side to side to pick up the scent of food. When a concentration of ants or termites is found, the Aardvark digs into it with its powerful front legs, keeping its long ears upright to listen for predators, and takes up an astonishing number of insects with its long, sticky tongue—as many as 50,000 in one night has been recorded. It is an exceptionally fast digger, but otherwise moves rather slowly.


    Burrow Park:

    Aside from digging out ants and termites, the Aardvark also excavates burrows to live in: temporary sites scattered around the home range as refuges, and the main burrow which is used for breeding.

    Burrow Basics:

    Main burrows can be deep and extensive, have several entrances, and can be as much as 13 meters long. The Aardvark changes the layout of its home burrow regularly, and from time to time moves on and makes a new one. Only mothers and young share burrows.






    After a gestation period of 7 months, a single cub weighing around 2 kg is born, and is able to leave the burrow to accompany its mother after only two weeks. At six months of age it is digging its own burrows, but it will often remain with the mother until the next mating season. The Aardvarks can grow older than 20 years in captivity.


    The

    Aardvark is the only surviving member of the family Orycteropodidae and of the order Tubulidentata. The Aardvark was originally placed in the same genus as the South American anteaters because of superficial similarities which, it is now known, are the result of convergent evolution, not common ancestry. For the same reason, Aardvarks bear a striking first-glance resemblance to the marsupial bilbies and Bandicoots of Australasia, which are not placental mammals at all. The Aardvark is now placed in its own genus, Orycteropus.










    The African wild dog

    (Lycaon pictus), also called African Hunting Dog or Painted Hunting Dog, is a mammal of the Canidae family, and thus related to the domestic dog. It is the only species in its genus, Lycaon, and the only species in the canid family to lack dewclaws on the forelimbs. They are, as their name indicates, found only in Africa, especially in scrub savanna and other lightly wooded areas.








    Painted Wolves:

    The Latin name of the species means painted wolf and no two individuals have the same pattern of coat.
    Their fur is an irregular pattern of black, yellow, and white. Some areas of the body are nearly hairless, and the skin is black.





    Packs, Man:

    African wild dogs hunt in packs. Their main prey are impala and similar medium sized ungulates. They're known for their stamina and for being clever hunters; they have been observed hunting prey in relays, or even blocking a potential escape route for prey.


    Family Values:

    Members of a hunting pack vocalize to help coordinate their movements. Their voice is characterized by an unusual chirping or squeaking sound, similar to a bird. After a hunt, dogs will often regurgitate meat for members of the group that have stayed behind, including the old, the lame, the pups, and subordinate adults who have taken on the responsibility of caring for the pups.





    Dogs in Danger:

    Their need for a large territory has led to the situation where today they are threatened with extinction. Their relatively small physique also makes them vulnerable to attacks by their competitors, lions and hyenas. The dogs are also killed by livestock herders and game hunters. They tend to be elusive and unlike most other members of the dog family, are extremely difficult to tame.
    The current estimate for remaining wild dogs in the wild is approximately 5,600. Of these, the majority live in the two remaining large populations associated with the Selous Game Reserve in Tanzania and the population centered in northern Botswana and eastern Namibia. Isolated populations persist in Zambia, Kenya, Mozambique, Zimbabwe and South Africa.





    All in the Family:

    They have a highly complex social system, within which related adult members cooperate to produce a single litter of pups annually. The breeding female occupies a den while she bears the pups, usually selecting an abandoned aardvark burrow for this purpose.


    It's Rainin' Males:

    Most populations have more males than females because more male pups appear in litters. It is very unusual among mammals to have this kind of gender bias.
    Females are more likely disperse from the natal group, and they readily join packs which have no sexually mature female members. In packs with more than one female, only one will be allowed to breed, leading to vicious rivalry between females.











    عضو في نادي ماركا الأكاديمي


  2. #2
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    افتراضي رد: The African Animals











    Apart from basic characteristics, antelopes differ from each other in appearance and physiology almost as much as they differ from other members of the cattle, goat, and sheep family. For example, the Common eland towers over most breeds of domestic cattle and can be 300 times heavier than the tiny Royal antelope.


    Legs:

    All antelopes have long, slender legs and powerful muscles where the upper legs meet the body, providing leverage and increasing leg stride and speed. Though antelopes are good jumpers, they are not particularly good climbers. A few do display good balance, such as the klipspringer, which stands on the tips of its hooves. The gerenuk, another African species, is one of the few antelopes that habitually stands on its back legs.


    Fur:

    Antelopes bear a dense coat with short fur. Most antelopes have fawn or brown-colored fur so they can camouflage themselves while eating. There are some exceptions, including the rare zebra duiker which has dark vertical stripes, and the gemsbok which has gray and black fur and a vivid black-and-white face. A common feature of the gazelle is a white rump, which flashes a warning to others when it runs from danger. One species of gazelle, the springbok, also has a pouch of white brushlike hairs running along its back. When a springbok senses danger, its pouch opens up, and the hairs stand on end.


    Diet:

    Antelopes are ruminants. Like other ruminants, such as cattle and sheep, they have well-developed cheek teeth or molars, which grind cud into a pulp. They have no upper incisors; in order to tear grass stems and leaves, their lower incisors press against a hard upper gum pad when they bite.


    Senses:

    Antelopes rely on their keen senses to avoid predators. Their eyes are on the sides of their heads, and their pupils are elongated horizontally, giving them a broad view of danger from both the back and front. Their senses of smell and hearing are also acute, giving them the ability to perceive danger while out in the open where predators often prowl after dark.


    Horns:

    Both sexes of most antelope species grow horns, though the males' horns are generally larger. The dik-dik and klipspringer, two species where the male mates with only one female, have horns that are little more than spikes. However, in species where males compete to mate with several females, horns may grow as long as 1.5 m (5 ft.). Despite their large size, antelope horns are hollow and lightweight. Antelope horns are almost always slightly curved, although in some species such as the blackbuck, they are shaped like a pair of corkscrews spiraling out in opposite directions.


    Males Are Larger:

    In many species, the males are larger than the females. In several species, such as the Asian blackbuck, males and females also differ in color.


    Life Span:

    Antelope life spans are hard to determine, and most known figures relate only to those in captivity. Captive gnus have lived to be over 20 years old, and captive impalas have lived into their late teens. In the wild, antelopes rarely live to their teens, as they are often preyed upon.





    Intelligence:

    Unlike carnivores and primates, herbivores such as the antelope are not noted for high intelligence. Since their food cannot run, antelopes do not have to be quick-thinking. However, they can be very clever in escaping from their enemies.




    Speed:

    Antelopes are fast runners, although they are not the fastest animals in the world. They are good at quick, precise turns, and they can run very fast for extended periods of time. This gives them an advantage over many predators such as the cheetah, which relies on sprinting and can be tired out by the antelope's greater stamina.

    Escape:

    The antelope's choice to flee is based largely on the type of predator and its distance from the herd. Usually, gazelles will permit lions to come within 200 m (650 ft.) before fleeing. They likely recognize that a hunting lion prefers to hide while stalking its prey, meaning a visible lion is unlikely to attack. Cheetahs, who are superb sprinters, pose a more dangerous threat. Gazelles will flee from cheetahs when they are over 800 m (0.5 mi.) away.


    Communication:

    Antelopes communicate with each other using a varied array of sounds. For example, dik-diks whistle when alarmed, warning other animals of danger as well. This characteristic makes dik-diks less favorable prey for hunters. Generally, though, sight is a much more common form of communication than sound among antelopes. An antelope's mood is indicated by its posture and movement. When excited or alarmed, most medium-sized species of antelope bounce up and down on all four legs, keeping them stretched out straight. This behavior, known as pronking or stotting, acts as an alarming display. Some biologists theorize that stotting also sends a message to predators, showing that individual antelopes are fit and alert, and therefore not worth pursuing.


    Scent:

    Antelopes also use scent signals to communicate; these signals can linger for many days. Antelopes that live in herds have special glands in their hooves that leave a scented record of their movement. If an antelope were accidentally separated from its herd, it would be able to follow the scent tracks back.


    Migration:

    Antelope species common to forests tend to stay in the same place all their lives, but species that live out in the open often migrate to feed and breed. The gnus carry out the most famous of these migrations through the plains and open woodlands of eastern and southern Africa. Gnus are sedentary in some places, but in others, such as Serengeti National Park, gnus travel between two different home ranges. One of these ranges is used during the dry season, while another is used during the wet season. Migration can be very risky; the dangers include crossing crocodile-infested rivers, but migration also supplies the gnus with food at different times of the year.






    There are about 90 species of antelope in about 30 genera, of which about 15 species are endangered. These include:
    * addax
    * bluebuck
    * bongo
    * bontebok
    * common eland
    * dik-dik
    * duiker

    * gazelle
    * gemsbok
    * hartebeest
    * impala
    * klipspringer
    * kudu
    * nyala

    * oribi
    * oryx
    * Grey Rhebok
    * roan antelope
    * royal antelope
    * sable antelope
    * springbok

    * suni
    * tibetan antelope
    * topi
    * waterbuck
    * wildebeest
    Imports: Blackbuck antelope have been imported into the United States, primarily for the purpose of "exotic game hunts," common and popular in Texas. There are no true antelope native to the Americas. The pronghorn antelope of the Great Plains belongs to the family Antilocapridae. The Mongolian gazelle (Procapra gutturosa), sometimes classified as an antelope, can run with a speed of 80 km/h (50 mph). Suni are small antelope that live in south-eastern Africa. They stand between 12-17 inches high at the shoulder and are very similar to the dik-dik in size, shape and color, but have many smaller differences.
    Antelope are not a cladistic group in and of themselves, but rather are considered a miscellaneous group. The term is used loosely to describe all members of the family Bovidae who do not fall under the category of sheep, cattle or goats. Native antelope can be found in Asia, India, and Africa.








    The baboons are some of the largest non-hominid members of the primate order; only the mandrill and the drill are larger. In modern scientific use, only members of the genus Papio are called baboons, but previously the closely related Gelada (genus Theropithecus) and two species of mandrill and drill (genus Mandrillus) were grouped in the same genus, and these monkeys are still often referred to as baboons in everyday speech. The word "baboon" comes from "babouin", the name given to them by the French naturalist Buffon.





    All baboons have long dog-like muzzles, close-set eyes, heavy powerful jaws, thick fur except on their muzzle, a short tail and rough spots on their rear-ends, called ischial callosities. These callouses are nerveless, hairless pads of skin which provide for the sitting comfort of the baboon. Males of the Hamadryas baboon species also have a large white mane.
    Size:

    There is considerable variation in size and weight depending on species, the Chacma baboon can be 120 cm (47 inches) and weigh 40 kg (90 lb) while the biggest Guinea baboon is 50 cm (20 inches) and weighs only 14 kg (30 lb).
    In all baboon species there is pronounced sexual dimorphism (the systematic difference in form between individuals of different sex in the same species), usually in size but also sometimes in color or canine development.
    Habitat:

    Baboons are terrestrial (ground dwelling) and are found in savanna, open woodland and hills across Africa. Their diet is omnivorous, but is usually vegetarian. They are foragers and are active at irregular times throughout the day and night. They can raid human dwellings and in South Africa they have been known to prey on sheep and goats.
    Man and leopard :

    Their principal predators are man and the leopard, although they are tough prey for a leopard and large males will often confront them.
    Life expectancy:

    Baboons in captivity have been known to live up to 45 years, while in the wild their life expectancy is about 30 years.






    Social structure:

    Most baboons live in hierarchical troops of 5 to 250 animals (50 or so is common), depending on specific circumstances, especially species and time of year. The structure within the troop varies considerably between Hamadryas baboons and the remaining species, sometimes collectively referred to as savannah baboons.


    Baboon harems:

    The Hamadryas baboon has very large groups comprised of many smaller harems (one male with four or so females), to which females from elsewhere in the troop are recruited while still too young to breed. The other baboon species have a more promiscuous structure with a strict dominance hierarchy based on the female matriline. The Hamadryas baboon group will typically include a younger male, but he will not attempt to mate with the females unless the older male is removed.
    Dominance:

    Baboons can determine from vocal exchanges what the dominance relations between individuals are. When a confrontation occurs between different families or where a lower-ranking baboon takes the offensive, baboons show more interest in the exchange than exchanges between members of the same family or when a higher-ranking baboon takes the offensive. This is because confrontations between different fam







    Both camel species are native to the dry and desert areas of Asia and northern Africa. The term camel is also used more broadly, to describe any of the six camel-like creatures in the family Camelidae: the two true camels, and the four South American camelids: Llama, Alpaca, Guanaco and Vicuña.






    One Hump, Please:

    The Dromedary camel (Camelus dromedarius) is a large even-toed ungulate native to northern Africa and western Asia, and is the best-known member of the camel family. The Dromedary has one hump on its back, in contrast to the Bactrian camel which has two. The Dromedary is sometimes called an Arabian camel. Some maintain that the name "dromedary" should be used to refer only to racing camels. The average life expectancy of a camel is 30 to 50 years.


    Thick Eyelashes and Small Ears:

    Male Dromedaries camels have a soft palate, which they inflate to produce a deep pink sack that out of the sides of their mouths during the mating season. Dromedaries are also noted for their thick eyelashes and small, hairy ears. Adults grow to a length of 10 feet and height of six to seven feet. Weight is usually in the range of 1000-1500 pounds.



    Two Humps, Please:

    The Bactrian camel (Camelus bactrianus) is a large even-toed ungulate native to the steppes of eastern Asia. The Bactrian camel has two humps on its back, in contrast to the Dromedary which has one. Nearly all of the estimated 1.4 million Bactrian camels alive today are domesticated, but in October 2002 the estimated 950 remaining in the wild in northwest China and Mongolia were placed on the critically endangered species list.

    Just the Facts:

    Bactrian camels are over 2 meters (7 feet) tall at the hump and weigh in excess of 725 kg (1,600 pounds). They are herbivores, eating grass, leaves, and grains, capable of drinking up to 120 liters (32 US gallons) of water at a time. Their mouth is extremely tough, allowing them to eat thorny desert plants. They are supremely adapted to protect themselves against the desert heat and sand; with wide, padded feet and thick leathery pads on the knees and chest, nostrils that can open and close, ears lined with protective hairs, and bushy eyebrows with two rows of long eyelashes. Thick fur and underwool keep the animal warm during cold desert nights and also insulate against daytime heat.


    Camel Olympian:

    Compared to the Dromedary camel, the Bactrian is a stockier, hardier animal being able to survive the scorching desert heat of northern Iran to the frozen winters in Tibet. The Dromedary is taller and faster, and with a rider it can maintain 8-9 mph for hours at a time. By comparison a loaded Bactrian camel moves at about 2.5 mph



    Of Camels and Men:

    Around the second millennium BC, camels became established to the Sahara region but disappeared again from the Sahara beginning around 900 BC. The Persian invasion of Egypt under Cambyses introduced domesticated camels to the area.
    Domesticated camels were used through much of North Africa, and the Romans maintained a corps of camel warriors to patrol the edge of the desert. The Persian camels, however, were not particularly suited to trading or travel over the Sahara; rare journeys made across the desert were made on horse-drawn chariots.
    The stronger and more durable Bactrian Camels first began to arrive in Africa in the fourth century. It was not until the Islamic conquest of North Africa, however, that these camels became common. While the invasion was accomplished largely on horseback, the new links to the Middle East allowed camels to be imported en masse.





    Police on Camels? These camels were well-suited to long desert journeys and could carry a great deal of cargo. For the first time this allowed substantial trade over the Sahara. Modern domesticated dromedaries are used for milk and meat and as beasts of burden for cargo and passengers. Unlike horses, they kneel for the loading of passengers and cargo. At many of the desert located tourist sites in Egypt, mounted police on camels can be seen.




    Gestation in the dromedary lasts around 12 months. Usually a single calf is born, and nursed for up to 18 months. Females are sexually mature after 3 to 4 years, males after 5 to 6 years. Lifespan in captivity is typically about 25 years, with some animals reaching the age of 50.





    Pass the camel's milk and sugar, please.

    Camel's milk is more nutritious than cow's milk. Their milk is lower in fat and lactose, and higher in iron, potassium and Vitamin C. The milk is drunk fresh as a warm and frothy liquid and in contrast to cow's milk tastes both heavy and sweet. In Arab countries, camels are reared for their milk.









    عضو في نادي ماركا الأكاديمي


  3. #3
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    افتراضي رد: The African Animals







    The Cheetah (Acinonyx jubatus) is an atypical member of the cat family (Felidae) that hunts by speed rather than by stealth or pack tactics. It is the fastest of all land animals and can reach speeds of up to 70 mph (112 km/h).

    The cat's meow.

    Cheetahs cannot roar like a lion, but they can meow, yelp, chirp, and purr.







    The cheetah has a slender, long-legged body with blunt semi-retractile claws. Its chest is deep and its waist is narrow.


    Sizes and Scales:

    The adult animal weighs from 40 to 65 kg (90 to 140 lb). Its total body length is from 112 to 135 cm (45 in to 55 in), while the tail can measure up to 84 cm (33 in). Male cheetahs are slightly larger than females and have a slightly bigger head, but it is difficult to tell males and females apart by appearance alone.


    Fur: the love of dots...

    The fur of the cheetah is yellow with round black spots, which help to camouflage it, and distinctive black lines that go from the inner corner of each eye and down along the side of the snout to the jaw. The cheetah's tail usually ends in a bushy white tuft.


    King Cheetahs:

    Cheetahs also have a rare fur pattern mutation: cheetahs with larger, blotchy, merged spots are known as 'King Cheetahs'. It was once thought to be a separate subspecies, but it is merely a mutation of the African Cheetah. A 'King Cheetah' has only been seen in the wild a handful of times, but they have been bred in captivity.


    Paws and Claws:

    The cheetah's paws have semi-retractable claws, unique among cat species, which offer the cat extra grip in its high-speed pursuits. It should be noted that the ligament structure of the cheetah's claws is the same as those of other cats; it simply lacks the sheath of skin and fur present in other varieties, and therefore the claws are always visible. With the exception of the dewclaw, the claw itself is also much shorter and straighter than other cats.



    Speed Demon:

    The cheetah's flexible spine, oversized liver, enlarged heart, wide nostrils, increased lung capacity, and thin muscular body make this cat the swiftest hunter in Africa. Covering 7-8 meters in a stride, with only one foot touching the ground at a time, the cheetah can reach a speed of 110 km/h in seconds. At two points in the stride, none of its feet touch the ground.






    The cheetah is well known for its amazing acceleration (0-100 km/h in 3.5 seconds which is faster than the SLR McLaren, the Lamborghini Murciélago and the F/A-18 Hornet).


    A Different Kind of Cat:

    Unlike true big cats, cheetahs can purr as they inhale, but cannot roar. By contrast, lions, tigers, leopards, and jaguars can roar but cannot purr, except while exhaling. However, cheetahs are still considered by many to be the smallest of the big cats. While it is often mistaken for a leopard, the cheetah does have distinguishing features, such as the long tear-drop shaped lines on each side of its nose that run from the corner of its eyes to its mouth. The body frame of a cheetah is also very different from that of the leopard, most notably so in its thinner and extra long tail.


    Adaptability: not...

    The cheetah is a vulnerable species. Out of all the big cats, it is the least able to adapt to new environments. They have always proved difficult to breed in captivity, but recently a few zoos have been successful. Once widely shot for its fur, the cheetah now suffers more from the loss of both habitat and prey.
    The cheetah is considered the most primitive of all cats, and until recently was thought to have evolved approximately 18 million years ago, although new research puts the last common ancestor of all 37 existing species of feline more recently, at 11 million years. The cheetah has lions and hyenas as natural enemies.





    Females:

    Unlike males, females are solitary and tend to avoid each other, though some mother/daughter pairs have been known to continue for small periods of time. Cheetahs have a unique, well-structured social order.
    Single Mother:

    Females live alone except when they are raising cubs and they raise their cubs on their own.
    The first 18 months of a cub's life are important - cubs learn many lessons because survival depends on knowing how to hunt wild prey species and avoid other predators such as leopards, lions, hyena, and baboons.
    At 18 months, the mother leaves the cubs, who then form a sibling, or 'sib', group, that will stay together for another 6 months. At about 2 years, the female siblings leave the group, and the young males remain together for life. Life span is up to 12 years in wild, but up to 20 years in captivity.


    Males:

    Male cheetahs are very territorial. Unfortunately, female cheetahs' home ranges can be very large and trying to build a territory around several females' ranges is impossible to defend. Instead, males choose the points at which several of the females' home ranges overlap, creating a much smaller space which can be properly defended against intruders while maximizing the chance of reproduction. Coalitions will try their utmost to maintain territories in order to find females with which they will mate. The size of the territory also depends on the available resources and depending on the part of Africa, the size of a cheetah's territory can vary greatly from 37 km2 to 160 km2.

    Social Butterflies:

    Male cheetahs are very sociable and will group together for life, usually with their brothers in the same litter, although if a cub is the only male in the litter then two or three lone males may group up or a lone male may join an existing group. These groups are called coalitions. A coalition is six times more likely to obtain a territory than a lone male, although studies have shown that coalitions keep their territories just as long as lone males - four to four and a half years.
    Males mark their territory by urinating on objects that stand out, such as trees, logs or termite mounds. The whole coalition contributes to the scent. Males will attempt to kill any intruders and fights often result in serious injury or death.
    Unlike males and other felines, females do not establish territories. Instead the area they live in is termed a home range. These overlap with other females' home ranges; often, it will be the females from the same litter or a daughter's home range overlapping with her mother's.


    Home Range:

    The size of a home range depends entirely on the availability of prey. Cheetahs in African woodlands have ranges as small as 34 km square, while in some parts of Namibia they can reach 1500 km square. Although there have been no studies, it is expected that the home ranges of females in the Sahara are the largest of all the cheetah populations.


    Communication Nation:


    When cheetahs attempt to find each other, or a mother tries to locate her cubs, they use high-pitched barking called yipping. The yips made by a cheetah cub sound more like a bird chirping, and so are termed chirping.
    Churring, stuttering or stutter-barking is a vocalization emitted by cheetahs during social meetings. A churr can be seen as a social invitation to other cheetahs, an expression of interest, uncertainty or appeasement or during meetings with the opposite sex (although each sex churrs for different reasons).

    Growling, often accompanied by hissing and spitting are exhibited by cheetahs during annoyance, or when faced with danger. A similar vocalization made by a cheetah when a threat is escalated is yowling.
    Purring is made when the cheetah is contented, usually during pleasant social meetings (e.g. a mother with her cubs).


    Hungry, Hungry Hunter:

    Cheetahs are carnivores, eating mostly mammals under 40 kg (90 lb), including Thomson's gazelles and impala. Wildebeest and calves are hunted when cheetahs hunt together. Guinea fowl and hares are also hunted. While the other big cats mainly hunt by night, the cheetah is a diurnal hunter. It hunts usually either early in the morning or later in the evening when it is not so hot, but there is still enough light - cheetahs hunt by vision rather than by scent.
    Prey is stalked to within ten to thirty meters (30-100 ft), then chased. Using their tails to maintain balance, cheetahs can make sharp turns if needed. Cheetahs are able to run at 60-70 miles an hour, but they chase their prey at only about half the speed. The chase is usually over in less than a minute and if the cheetah fails to make a quick catch, it will often give up rather than waste energy.


    Cheetah Table Manners:

    Roughly half of their chases are successful. The cheetah kills its prey by tripping it during the chase, then biting it on the underside of the throat to suffocate it, for the cheetah is not strong enough to break the necks of the gazelles it mainly hunts. The bite may also puncture a vital artery in the neck. Then the cheetah proceeds to devour its catch as quickly as possible before the kill is taken by stronger predators such as lions, leopards and hyenas.


    Domesticated Cheetahs?

    In much of their former range they were domesticated by aristocrats and used to hunt antelopes in much the same way as is still done with members of the greyhound group of dogs. Aside from an estimated 200 cheetahs living in Iran (Khorasan Province), the distribution of cheetahs is now limited to Africa. There are 5 subspecies of cheetah in the genus Acinonyx: four in Africa and one in Iran.


    Out of India:

    The endangered subspecies Acinonyx jubatus venaticus lives in Asia (Iran). In 1990, there were reports in the Times of India of a cheetah sighting in eastern India. There is a chance some cheetahs remain in India, though it is doubtful. There have also been reports of Asiatic cheetahs in the Balochistan Province of Pakistan, though these continue to be unverified. The cheetah prefers to live in an open biotope, such as semi-desert, prairie, and thick brush.






    The genus name, Acinonyx, means "no-move-claw" in Greek, while the species name, Justus, means "manned" in Latin, a reference to the mane found in cheetah cubs. It is the only cat that cannot completely retract its claws. Even when retracted, the claws remain visible and are used for grip during the cheetah's acceleration and maneuvering, performing the same function as canine claws.
    The English word "cheetah" comes from Hindi chit, which is perhaps derived from Sanskrit shiitake, meaning "the spotted one". Other major European languages use variants of the medieval Latin gatt us pads, meaning "cat-leopard i.e. spotted cat": French geared; Italian Sheppard; Spanish and Portuguese geared (also used chit); and German geared.
    Cheetahs have unusually low genetic variability and high abnormal sperm count. Skin grafts between non-related cheetahs illustrate this point in that there is no rejection of the donor skin. It is thought that they went through a prolonged period of inbreeding following a genetic bottleneck during the last ice age. They probably evolved in Africa during the Miocene epoch (26 million to 7.5 million years ago), before migrating to Asia. New research by a team lead by Warren Johnson and Stephen O’Brien of the Laboratory of Genomic Diversity (National Cancer Institute in Frederick, Maryland, US) has recently placed the last common ancestor of all existing cat species as living in Asia c. 11 million years ago, which may lead to revision and refinement of existing ideas about cheetah evolution.











    The chimpanzee is the common name for the two living species in the genus Pan: The common Chimpanzee and The Bonobo. Pan troglodytes, the Common Chimpanzee, lives in West and Central Africa. Its cousin, the Bonobo or "Pygmy Chimpanzee," (Pan paniscus), is found in the forests of the Democratic Republic of the Congo. The two species are separated by the Congo River.


    How do I look?

    Chimpanzees can recognize themselves in the mirror.

    Chimps use their expressive faces with vocalizations for communication, much like humans engage in conversations. When they grunt they are happy, while their 'smile' actually shows fear or anxiety.




    Lighter than humans, but stronger:

    Adults (common Chimpanzees) in the wild weigh between 40 and 65 kg (88 and 143 lb); males can measure up to 160 cm (63 inches) and females to 130 cm (51 inches), and although lighter than humans they have a pull 5-6 times stronger . This is because the muscles of chimpanzees and other primates are far more effective than those of humans.
    Their bodies are covered by a coarse dark brown hair, except for the face, fingers, toes, palms of the hands and soles of the feet. Both their thumbs and their big toes are opposable, allowing a precision grip.






    Warm and moist regions :

    Common Chimpanzees are found in the tropical forests and wet savannas of Western and Central Africa. They used to inhabit most of this region, but their habitat has been dramatically reduced in recent years.

    Diet:

    Although omnivores, their diet is mainly vegetarian, consisting of fruits, leaves, nuts, seeds, tubers, and miscellaneous plantlife supplemented by insects and small prey. There are also instances of organized hunting; in some cases, such as the killing of leopard cubs, this seems to be primarily a protective effort. However, Common Chimpanzees sometimes band together and hunt Western Red Colobus monkeys (Piliocolobus badius) for their meat. Isolated cases of cannibalism have been documented. Chimpanzees have also been known on rare occasions to attack and eat human infants.


    Large communities:

    Common Chimpanzees live in communities that typically range from 20 to more than 150 members, but spend most of their time traveling in small parties of just a few individuals.



    Usually on 4, but sometimes 2:

    They are both arboreal and terrestrial, spending equal time in the trees and on the ground. Their habitual gait is quadrupedal, using the soles of their feet and resting on their knuckles, but they can walk upright for short distances.


    A changing society:

    The Common Chimpanzee lives in a fission-fusion society, where mating is promiscuous, and may be found in groups of the following

    types:
    all-male, adult females and offspring, bisexual, one female and her offspring, or a single individual. The core of the societies are males who roam around, protecting members of the group as well as engaging in the search for food. Among males, there is generally a dominance hierarchy. However, this unusual fission-fusion social structure, "in which portions of the parent group may on a regular basis separate from and then rejoin the rest", is highly variable in terms of which particular individual chimpanzees congregate at a given time. This is mainly due to chimpanzees having a high level of individual autonomy within the fission-fusion society. Also, communities have large ranges that overlap with those of other groups.


    Smaller foraging:

    As a result, individual chimpanzees often forage for food alone, or in smaller groups (as opposed to the much larger parent group, which encompasses all the chimpanzees who regularly come into contact and congregate into parties in a particular area). As stated, these smaller groups also emerge in a variety of types, for a variety of purposes. For example, an all-male troop may be organized in order to hunt for meat, while a bi-sexual group consisting of one mature male and one mature female may occur for the purposes of copulation. An individual may encounter certain individuals quite frequently, but have run-ins with others almost never or only in large-scale gatherings. Due to the varying frequency at which chimpanzees associate, the structure of their societies is highly complicated.







    Pan:

    The genus Pan is now considered to be part of the subfamily Homininae to which humans also belong. Biologists believe that the two species of chimpanzees are the closest living evolutionary relatives to humans. It is thought that humans shared a common ancestor with chimpanzees and gorillas as recently as four to seven million years ago, and that they have about 95 to 99.4 percent of their DNA in common with humans, with at least some of the difference occurring in 'junk' DNA. It has even been proposed that troglodytes and paniscus belong with sapiens in the genus Homo, rather than in Pan.


    Human observation:

    The 20th century saw a new age of scientific research into chimpanzee behaviour. Prior to 1960, almost nothing was known about chimpanzee behavior in their natural habitat. In July of that year, Jane Goodall set out to Tanzania's Gombe forest to live among the chimpanzees. Her discovery of chimpanzees making and using tools was groundbreaking, as it had previously been believed that humans were the only species to do so.





    Astronaut Chimpanzee: Chimpanzees entered outer space before humans did! Chimpanzees are so intelligent that one named Ham orbited the Earth in 1961. In fact, Mercury astronaut Alan Shepard followed Ham into space three months later!
    In December 1960 the 44-month old chimpanzee was trained to do simple tasks in response to electric lights and sounds, with response being timed. On January 31, 1961, Ham was secured in a Project Mercury capsule labeled MR-2 and launched from Cape Canaveral, Florida into outer space. The capsule suffered a partial loss of pressure during the flight, but Ham's space suit prevented him from suffering any harm. During the flight Ham had to push a lever within five seconds of seeing a flashing blue light; as he was taught in pre-flight training. Ham's performance in space was only a fraction of a second slower than on Earth, demonstrating that tasks could be performed in space. Ham's capsule splashed down in the Atlantic Ocean and was recovered by a rescue ship later that day.





    Losing our chimpanzee cousins:

    Unfortunately, also because they are so intelligent and that they can be taught, chimpanzees are often involved in scientific studies, or caught and sold as pets. Because so many chimpanzees have been taken from the wild, and because some people hunt chimpanzees for bushmeat (food) there has been a huge drop in their population. All these factors, in addition to the human takeover of habitat have caused these intelligent beings to become endangered.





    عضو في نادي ماركا الأكاديمي


  4. #4
    Super Moderator الصورة الرمزية منى زهران
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    Mar 2012
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    افتراضي رد: The African Animals






    Loxodonta is a genus in Elephantidae, the family of elephants and is divided into two species.
    The African Bush Elephant (Loxodonta africana) is the better-known and larger of the two species of African elephants. Both it and the African Forest Elephant were previously classified as a single species, known simply as the African Elephant. It is also known as the Bush Elephant or Savanna Elephant.



    He's really let himself go.

    African Bush elephants are the largest land animals in the world.

    They can weigh about 22,000 lbs and grow to 20 to 24 ft.

    Although huge, they are surprisingly fast animals; when frightened they can run about 24 miles an hour.










    Sizes and Scales:

    The African Bush Elephant

    is the largest land dwelling animal, normally reaches 6 to 7.3 m (20 to 24 ft) in length and 3 to 3.5 meters in height, although a 4-meter elephant, the body of which is mounted in the rotunda of the National Museum of Natural History in Washington, D.C., was discovered in Angola in 1955.


    Big and Brisk:

    Weighing between 7,000 and 10,000 kg (15,000-22,000 lb), it is the largest land animal in the world. It moves at a rate of 6 km/h, but it can reach a top speed of 40 km/h when scared or upset.

    Big-headed:

    The animal is characterized by its large head; two large ears that cover its shoulders and radiate excess heat; a large and muscular trunk; two prominent tusks, which are well-developed in both sexes, although more commonly in males; a short neck; a large, barrel-like body; four long and heavy legs that resemble columns; and a relatively short tail.


    Thick Skinned:

    The animal is protected by a heavy but flexible layer of gray-brown skin, dotted with mostly undeveloped patches of hair and long, black hair at the tip of its tail. Its back feet have three toes that form a hoof, while the number of toes on the front feet have varied between four and five, in different instances. The front is smoother and less convex than that of the Asian Elephant.


    Nose + Lip = Trunk:

    The trunk is the most characteristic feature of the African Bush Elephant. It is formed by the fusion and elongation of the nose and upper lip, forming a flexible and strong organ made purely of muscle.



    Intellectual Giants?

    A recent report states that African elephants are able to use seismic vibrations at infrasound frequencies for communication. The African Bush Elephant is a notably intelligent animal. In fact, experiments about reasoning and learning applied on them show that they are the smartest ungulates together with their Asian cousins. This is mostly due to their large brain.

    African & Asian:

    Differences between the African Bush Elephant and the African Forest Elephant include the Forest Elephant's long, narrow mandible (the African Bush Elephant's is short and wide), its rounded ears (an African Bush Elephant's ears are more pointed), different tusks, and considerably smaller size. The Male African Forest Elephant rarely exceed 2.5 meters (8 feet) in height, while the African Bush Elephant is usually over 3 meters (just under 10 feet) and sometimes almost 4 meters (13 feet) tall.






    What's on the menu?

    African elephants are herbivorous. The diet of the African Bush Elephant varies according to its habitat; elephants living in forests, partial deserts, and grasslands all eat different proportions of herbs and tree or shrubbery leaves.


    Chew on this! In order to break down the plants they consume, the African Bush Elephant has four large molars, two in each mandible of the jaw. Each of these molars is 10 cm wide and 30 cm long. Over time, these molars are worn away and new ones are grown to replace them as the elephant ages. Around the age of 15 their milk teeth are replaced by new ones that last until the age of 30, and then by another set which wear off past the age of 40, being replaced by the last set of teeth that last approximately until the age of 65–70. Not much later, the animal dies of starvation from not being able to feed correctly. There are known cases of over 80 year old specimens in captivity.


    Big Appetite:

    These animals typically ingest an average of 225 kg of vegetable matter daily, which is defecated without being fully digested. That, combined with the long distances that they can cover daily in search of more food, contributes notably to the dispersion of many plant seeds that germinate in the middle of a nutrient-filled feces mound. In their feeding-oriented whereabouts, elephants rip apart all kind of plants, and knock down trees with the tusks if they are not able to reach the tree leaves not even standing up straight, as actual living bulldozers. It can be said that they carry devastation with them. That causes deep trouble for other species and to the elephants themselves in national parks where there is overpopulation, so that managers of overpopulated parks often contact other parks with fewer specimens to transfer excess individuals.


    Thirst Quencher:



    Elephants also drink great quantities of water, over 190 liters per day.

    Mothers Rule:

    Herds are made up of related females and their younglings of assorted ages, directed by the eldest female, called the matriarch. Infrequently, an adult male goes with them, but those usually leave the pack when reaching adolescence to form herds with other elephants of the same age. Later, they spread out, carrying out a lonely life, approaching the female herds only during the mating season. Nevertheless, elephants don't get too far from their families and recognize them when re-encountered. Sometimes, several female herds can blend for a period of time, reaching even hundreds of individuals.


    Herd Is Where The Heart Is:
    The matriarch is the one who decides the route and shows to each other member of the herd all the water sources she knows, which the rest will memorize in the future.
    The relations among the members of the herd is very tight; when a female gives birth to a baby the rest go to acknowledge it by touching her with the trunk; and when an old elephant dies the rest of the herd will stay by the corpse for a while.

    The famous elephant graveyards are a myth, but it is true that these animals can recognize a carcass of its species when they find one during their trips, and even if it is a stranger, they form around it and sometimes they even touch its forehead with their trunk.


    Killing Rhinos:

    Some African Bush Elephants will attack and kill rhinoceroses. This behavior, when it occurs, is mostly observed with younger adult male elephants who have come into musth prematurely.


    Natural Predators:

    The adult African Bush Elephant lacks natural predators thanks to its great size, but the calves (especially the newborn) are vulnerable to lion, leopard, crocodile, and, more rarely, hyena attacks. Adult females of a group will attack approaching predators. Predation, as well as drought, contribute significantly to infant mortality.
    Human Predators: Humans are the elephant's major predator. Elephants have been hunted for meat as well as the rest of the body, including skin, bones, and tusks. Elephant trophy-hunting increased in the 19th and 20th centuries, when tourism and plantations increasingly attracted sport hunters.
    In 1989, hunting of the African elephant and ivory trading were forbidden, after the elephant population fell from several million at the beginning of the 20th century to fewer than 700,000. The population of African elephants was halved during the 1980s. Scientists then estimated that, if no protective measures were taken, the wild elephant would be extinct by 1995. The protection that the elephant now receives has been partially successful, but despite increasingly severe penalties imposed by governments against illegal hunting, poaching is still common. CITES still considers this species as threatened with extinction.

    Birds and Bees: Mating for a African Bush Elephant happens when the female feels ready, an event that can occur anytime during the year. When she is ready, she starts emitting infrasounds that attract the males, sometimes many kilometers away.
    The adult males start arriving to the herd during the following days and begin fighting head-to-head between them, causing some injuries and even broken tusks. The female shows her acceptance of the victor by rubbing her body against his. They mate, and then both go their own way.
    Incredibly Long Pregnancy: After 22 months of gestation (the longest among mammals), the female gives birth to a single 90cm-high calf which weighs more than 100 kg.
    The baby feeds on the mothers milk until the age of 5, but also eats solid food from as early as 6 months old. Just a few days after birth the calf can follow the herd by foot, and so the herd resumes its course.




    Classification Confusion: Until recently, it was thought that the so-called African Forest Elephant (Loxodonta cyclotis) was simply a subspecies of the African Bush Elephant (Loxodonta africana).
    DNA testing has now shown that there are in fact three extant elephant species: the two African types (formerly considered to be separate populations of a single species, the African Elephant) and the South Asian species, known as the Indian or Asian Elephant. The North African elephant of Hannibal fame was a now-extinct fourth species or a subspecies of the Forest Elephant (Loxodonta (africana) pharaoensis); it disappeared around the 1st or 2nd century CE.
    The disputed Pygmy Elephants of the Congo basin, often assumed to be a separate species (Loxodonta pumilio) by cryptozoologists, are probably Forest Elephants whose diminutive size and/or early maturity is due to environmental conditions.
    Late in the 20th century, conservation workers established a DNA identification system to trace the origin of poached ivory. It had long been known that the ivory of the African Forest Elephant was particularly hard, with a pinkish tinge, and straight (whereas that of the African Bush Elephant is curved). The DNA tests, however, indicated that the two populations were much more different than originally thought—indeed, in its genetic makeup, the African Forest Elephant is almost two-thirds as distinct from the African Bush Elephant as the Asian Elephant is.



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