Реферат: Cheetahs Essay Research Paper CheetahsThe cheetah belongs

Cheetahs Essay, Research Paper

Cheetahs

The cheetah belongs to Kingdom: Animalia, Phylum: Chordata, Class Mammalia, Order: Carnivora, Family: Felidae, Genus: Acinonyx, and Species: Jubatus. Therefore, its scientific name is Acinonyx Jubatus. The cheetah s distinguishing marks are the long tear-drop shaped lines on each side of the nose from the corner of its eyes to its mouth. The coat is tan, or buff

colored, with black spots measuring from + to 1 + inches across. There are no spots on its white belly, and the tail has spots which merge to form four to six dark rings at the end. The tail usually ends in a bushy white tuft. Distinctive individual ring patterns on the tail enable the identification

of specific cheetahs (by humans). An adult cheetah weighs 80-140 lb., is about 32 in. tall at the shoulder and 48-56 in. long with another 28-32 in. in the tail. Males are a little larger than females. Cheetahs are sometimes mistaken for leopards which are much heavier animals with rosette shaped spots and no tear marks. Of all the big cats, the cheetahs have the least strength and as a result they and/or their cubs are often killed.

The Cheetah is most famous for its speed and can accelerate from zero to 40 mph in three strides and to full speed of 70 mph in seconds. The cheetah is aerodynamically built for this speed. As the cheetah runs, only one foot at a time touches the ground. There are two points, in its 20 to 25 foot stride when no feet touch the ground, as they are fully extended and

then totally doubled up. Nearing full speed, the cheetah is running at about 3 + strides per second. The cheetah s respiratory rate climbs from 60 to 150 breaths per minute during a high-speed chase and can run only 400 to 600 yards before it is exhausted; at this time it is extremely vulnerable to other predators, which may not only steal its prey, but attack it as well.

The cheetah has specialized for speed through many adaptations: It is endowed with a powerful heart, oversized liver, and large, strong arteries. It has a small head, flat face, reduced muzzle length allowing the large eyes to be positioned for maximum binocular vision, enlarged nostrils, and extensive air filled sinuses. Its body is narrow, lightweight with long, slender feet and legs, and specialized muscles, which act simultaneously for high acceleration and allowing greater swing to the limbs. Its hip and shoulder girdles swivel on a flexible spine that curves up and down, as the limbs are alternately bunched up and then extended when running, giving greater reach to the legs. The cheetah s long and muscular tail acts as a stabilizer for balance to counteract its body. The cheetah is the only cat with short, blunt semi non-retractable claws that help grip the ground for traction when running. Their paws are less rounded than the other cats, and their pads are hard, similar to tire treads, to help them in fast, sharp turns.

Cheetahs are distributed primarily throughout the drier parts of sub-Saharan Africa. They are not generally associated with forest habitats: they occur only thinly in the more humid zones of woodland that cover much of central southern Africa. However, although cheetahs are most frequently observed on open grassy plains, they also make extensive use of bush, scrub, and

open woodlands.

Cheetahs have a unique, well-structured social order. Males live alone or in coalitions made up of brothers from the same litter. Young males seek out an area at a great distance from their parent; sometimes as far as 300 miles away. Territories are often located in areas where there is a rich supply of wild game and/or water. This coalition will live and hunt together for life

and claims a range which may overlap several female territories. Some coalitions maintain territories in order to find females with which they will mate. Fierce fights between male coalitions, resulting in serious injury or death, can occur when defending territories. The average size of male territories is 37.4 km2. Young females, however, usually occupy the same range as their mother although all females are solitary except when they have a litter. Their average home range extends to 833 km2. Males and females mix only to mate.

Sexual maturity occurs at 20-23 months. Unlike most cats, cheetahs breed throughout the year without a regular breeding season. Following a gestation period of 90-98 days a litter of 1-8 cubs will be born. The typical litter is about 4-5 cubs. At birth cubs are about 11.8 inches long and weigh 0.6 pounds. They are a gray color with a mantle of hair along the back. This

mane-like growth, which possibly helps camouflage the cub in grass, begins to disappear at 3 months but may still be seen at 2 years of age. Only a few cubs reach adulthood: lions and hyenas are their greatest threat. Males do not take part in raising the cubs. The mother raises them on her own. During their first few weeks of life the mother moves her cubs every few daysto avoid predators. But she must leave them alone to hunt and mortality is very high, about 80% are killed during this period. Juveniles stay with the mother for 16 to 24 months and following this period the litter members live together for a time perfecting their hunting skills. When the female reaches sexual maturity she either leaves her brothers or they are separated from her by older males. The life span of wild cheetahs are not too clear but it could be as high as the age of 12. However in captivity the average life span is 8-12 years. Cub mortality is high for the species in both the wild and captivity. On average 30 percent of all cubs born in captivity die within one month of birth, and in Tanzania’s Serengeti National Park, about 90 percent die before reaching the 3 months of age.

A cheetah is carnivorous and eats a variety of small animals. While most cats are nocturnal predators, the cheetah is diurnal, hunting in early morning and late afternoon. Dependent on sight rather than smell, it likes to scan the countryside from a tree limb or the top of a termite mound. Unlike other big cats who chase only a few hundred meters, the cheetah

chases 3.4 miles at an average speed of 45 mph. The stalk is as important as the sprint, it usually will try to get within 50 yards of the intended victim before the final acceleration. Full sprints last about 20 seconds and almost never exceed 1 full minute. The cheetah suffocates most of its captives by closing its jaws about the animal’s windpipe and compressing, sometimes

as long as 5 minutes. Smaller animals, like hares are killed by biting through the skull and, whatever the meal, the cheetah eats quickly for if challenged it will most often lose. Cheetahs have unusually clean eating habits, they do not return to their kill nor do they eat carrion; they leave the skin, bones and entrails of their prey. At 6 weeks the young are strong enough to

follow the hunt and when they are about 6 months old the mother will capture live prey for them to practice killing. Cheetah eat small antelope – springbok, steenbok, duikers, impala and gazelle; the young of larger animals – warthog, kudu, hartebeest, oryx, roan and sable; as well as game birds and rabbits. They can even mimic some bird sounds, perhaps to attract them. One

of their favorite catches, Thompson’s Gazelle, is a common resident of the east African plains. These small antelopes are about 23-28 inches tall and 28-43 inches long. Cheetahs favor fawns or half-grown antelope and look for animals which have strayed some distance from the group. They do not seek out old or weak animals.

Cheetahs do not roar like lions and tigers. Instead, they make chirping sounds and hiss when angered or threatened. When alarmed, they whine or growl. They purr loudly when content. They do not roar. The cats have a good sense of smell and communicate by scenting tree trunks, bushes and termite mounds with their waste.

The cheetah originated about 4 million years ago, long before the other big cats. The oldest fossils place it in North America in what is now Texas, Nevada and Wyoming. It was common throughout Asia, Africa, Europe and North America until the end of the last Ice Age,

about 10,000 years ago, when massive climatic changes caused large numbers of mammals to disappear. All cheetahs in North America and Europe and most of those in Asia and Africa vanished. It has been estimated that in 1900, more than 100,000 cheetahs were found in at least 44 countries throughout Africa and Asia. Today the species is extinct from +20 countries and

between 9,000 12,000 animals remain, found mostly in small-pocketed populations in 24 to 26 countries in Africa and +200 in Iran. Present estimates place their number at 9 – 12 thousand with about 1/10 of those living in captivity. There are now only two remaining population

strongholds: Namibia/Botswana in southern Africa, and Kenya/Tanzania in East Africa. Namibia is the cheetah capital of the world. It is home to nearly 2,000 of the big cats, or one-sixth of the world’s remaining cheetahs.

The cheetah is classified as an endangered species. One cause of the decline of the cheetahs is due to the inbreeding that occurred because of the small numbers 10,000 years ago. the consequences of such genetic uniformity have led to reproductive abnormalities, high infant mortality, and greater susceptibility to disease, causing the species to be less adaptable and

more vulnerable to ecological and environmental changes. To increase genetic diversity in captivity, zoos take great care to make sure that only unrelated animals mate. Scientists are working on ways to enhance breeding through artificial insemination, and in vitro fertilization(IVF).

The main reason they are endangered is because of the removal of live cheetahs from the wild into captivity, the use of cheetahs for sport hunting, and the fur market have contributed to a decline in the species. Human excess is probably the major factor pushing the cheetah toward extinction. Too many people squeeze out other species, robbing them of living space and

limiting their food supply. Also, habitats have been reduced by agriculture, degradation of rangelands and competition from domestic stock, following increasing occupation of the habitat by human communities.

Despite all these problems, the cheetah is the oldest of the big cats and has survived the longest. If we can provide a habitat and a rich prey base for cheetahs on the livestock farmlands of southern Africa, the cheetah’s race will be one of survival, not extinction.

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