: animals


06-24-2014, 10:59 PM
animals

Elephants

Introduction
Elephant, Brobdingnagian vertebrate characterised by a long muscular snout and two long, curved tusks. highly intelligent and powerful, elephants square measure the most important land animals and square measure among the longest-lived, with life spans of 60 years or more. Healthy, big elephants have no natural enemies aside from humans.
Throughout history, folks have prized elephants for their nice size and strength
. On the piece of land, soldiers astraddle elephants have trodden and afraid enemies. Elephants also have been trained to hold heavy provides through jungles and to haul Brobdingnagian logs from the forests where they once lived.
Elephants have long been revered and honored, and in Kingdom of Thailand, India, and alternative Southeast Asian countries, superbly adorned elephants still play a big role in traditional spiritual ceremonies. in step with Buddhist tradition, Siddhartha selected the form of a white elephant as one of his several terrene incarnations, and therefore the rare look of a white elephant remains heralded as a manifestation of the gods.
Over the past forty million years, more than 600 species of elephants have roamed the world. these days solely two species square measure alivethe african elephant and therefore the Asian elephant. Climate fluctuations over the millennia and ensuing vegetation changes caused the extinction of the many elephant species, but human impact has conjointly taken its toll. At the turn of the 20th century, elephants numbered from 5 million to ten million, but widespread hunting ANd surround destruction reduced their numbers to an estimated 640,000 by the top of the century. contemporary efforts to save elephants could also be inadequate, and biologists square measure unsure if elephants as a species will survive.

Evolution
The earliest familiar ancestors of modern elephants evolved regarding 65 million years agone in the region currently referred to as Egypt. referred to as Moeritherium, these swamp-dwelling animals were from pig- to cow-sized, with AN elongated snout but no trunk. They sported two pairs of slightly elongated front teethindicators of what would eventually evolve into tusks. 3 groups of elephant-like animals descended from Moeritherium: Deinotherioidea, Mastodontoidea, and Elephantoidea. Deinotherioidea evolved from 54 million to thirty eight million years agone and lived in elements of Asia, Europe, and Africa. It possessed a trunk and two tusks, that pointed backward, probably for hoeing up food from the sides and bottoms of swamps. The last extant members of this group died out regarding ten,000 years agone.
The earliest members of the Mastodontoidea group evolved regarding thirty eight million years agone. These animals had elephant-like trunks, and, counting on the family, displayed either two or four tusks. The upper tusks were vertical, or upward inform. The lower set, once gift, bent forward and were typically formed like shovels, apparently for dig plant roots and bulbs. The mastodont, the most acquainted member of this group, evolved regarding 15 million years agone, and unfold to Europe, Asia, Africa, and North America. Its descendants lived in the cold world of the last nice Ice Age2.5 million to 8000 years agone, once thick glaciers coated elements of North America and Europe. The mastodont had two tusks that curved upward and was coated with a thick coat of shaggy hair. About 10,000 years agone, early humans began hunting mastodons, contributing to their extinction.
The Elephantoidea group, that evolved 8 million to ten million years agone, includes the mammoth and Stegolophodon. The mammoth conjointly lived throughout the period and
[align=center]was coated with a thick, woolly coat. in contrast to the mastodons forward-curving tusks, the mammoths tusks curved backward. The mammoth displayed a outstanding hump on its back. Mammoths roamed North America, Africa, Europe, and Asia, were afraid by early humans, and died out regarding 8000 years agone. Stegolophodon evolved regarding an equivalent time because the mammoth and owner-occupied Europe, Asia, and Africa. Its tusks and alternative options were intermediate between the mammoth and modern elephants. Stegolophodons descendants square measure the African and Asian elephants of these days.

Range and surround
Fossils of elephant ancestors indicate they once lived on each continent except Australia and Antarctic continent, but elephant surround these days is restricted to Africa and elements of geographical region. Elephants occupy AN array of environments in Africa and Southeast Asiagrasslands, marshes, forests, deserts, and mountains. they are herbivores, or plant eaters, and need nice quantities of food to sustain their large size. They conjointly need plenty of potable then square measure restricted to areas with ample vegetation and adequate water.
Even little herds of some elephants will quickly drop the food and water resources of a section, forcing them to keep on the move. A herd of elephants migrates seasonally in AN extended loop, yearning for fresh resources among its home range, which can extend over 1500 sq kilometre (600 sq mi). In its hunt for food, AN elephant will travel 5000 to ten,000 kilometre (3100 to 6200 mi) in one year, the longest vertebrate migration on record.

Physical De@_@@_@@_@@_@@_@@_@ion
African and Asian elephants differ in size, color, and alternative physical characteristics. The african elephant are often distinguished by its larger size and broader ears that drape over its shoulders. Males, or bulls, could reach four m (13 ft) in height and weigh 7000 weight unit (15,400 lb). Females, or cows, square measure shorter, averaging two.8 m (9 ft) in height, and weigh significantly less, regarding 3600 weight unit (7900 lb). African elephants square measure lightweight grey in color, though they will seem dark grey, red, or brown from the mud they bathe in. they have a low, flat forehead and a slightly swayed back. Their fan-shaped ears average one.5 m (5 ft) long and one.2 m (4 ft) wide . both bulls and cows have long, curved tusks.
Asian elephants square measure shorter and stockier than their African relatives, with ears that don't reach their shoulders. the typical Asian bull stands three m (10 ft) tall and weighs 2300 weight unit (5100 lb), regarding [*fr1] the burden of male African elephants. Cows reach a mean height of two.4 m (7.8 ft) and weigh a mean of 3000 weight unit (6600 lb). Asian elephants have dark grey skin, a bulbous forehead, and a rounded back. Ear size averages 0.75 m (2.5 ft) long and 0.6 m (2 foot wide). The cows tusks could also be either absent or undeveloped.
Despite their nice weight, elephants walk nearly noiselessly with exceptional grace, their columnar legs keeping their bulk moving forward in sleek, throbbing strides. A thick cushion of resilient tissue grows on the base of every foot, absorbing the shock of the burden. The toes facilitate balance the burden in walking. Elephants commonly walk at a speed of regarding six km/h (about four mph) and might charge at up to forty km/h (25 mph). they can not gallop or hop over ditches, but readily take to rivers and lakes, where the water supports them and allows them to swim long distances without wearying.
An elephant's nose and upper lip square measure combined during a long, limber trunk, AN exceptionally supple appendage with AN estimated 150,000 muscle units. The versatile trunk acts like a hand for grasping low-growing shrubs and alternative food and inserting it

into the mouth; AN arm for gap tree branches; or a snorkel for breathing once the elephant's body is submerged. Elephants conjointly use their trunks to suck up water and squirt it into their mouths for drinking or over their bodies for bathing. Nostrils at the trunks tip enable elephants to discover odors. For faint scents, elephants sample the air with their nostrils. They then place the trunk in the mouth, where special organs devour the odor. African elephants have two little, versatile lips at the top of the trunk for selecting up little ******s. Asian elephants have only 1 lip at the top of the trunk, that they use for an equivalent purpose.
Elephant tusks, the paired, elongated upper incisors, or teeth, square measure the most important and heaviest teeth of any living animal. The tusks square measure used for dig for roots and water, remotion the bark off trees for food, fighting each other throughout sex activity season, and, in african elephant cows, averting predators of baby elephants such as lions and tigers. In a calf, the first incisors square measure replaced among six to 12 months of birth, and therefore the second set, that becomes the tusks, grows at the speed of regarding 17 cm (about seven in) each year throughout life. Tusk growth is set by genetics and nutrition, and over the years, normal wear and tear scales down their length. AN African bull tusk typically weighs twenty to 45 weight unit (50 to one hundred lb) and is one.8 to 2.4 m (6 to 8 ft) long. The tusks of AN adult Asian bull average one.5 m (5 ft) long and 30 weight unit (70 lb) in weight. The more large tusks of the african elephant, and therefore the undeniable fact that both bulls and cows have tusks, build these animals a more desirable target for ivory hunters than Asian elephants.
Elephants have a complete of 4 teeth, all molars, that have jagged ridges for grinding leaves, stems, and roots. a single tooth will weigh more than 5 weight unit (11 lb) and measure 30 cm (12 in) long. the first try of molars is found toward the front of the mouth; once these front molars subsume, they drop move into items because the two molars in the back shift forward. two new molars then emerge in the back of the mouth to exchange those who have affected forward. Elephants replace the back molars sixfold throughout life. once the last set of molars wears outanywhere between forty and regarding 60 years of agean elephant will no longer chew food and dies of starvation, a not uncommon death among elephants.
Elephant skin is wrinkled and thick (2.5 cm/1 in) with a sparse covering of bristle-like hair. Despite its thickness, the skin is subject to infection by lice, ticks that carry blood-borne diseases, and therefore the larvae of the warble fly, that bore into the elephants body and cause swelling and hemorrhage. Elephants oftentimes cover themselves with dust, bathe in water, and take mud baths to guard their skin.
Elephants lack sweat glands in their skin and their ears act like radiators for releasing body heat. By wave them, AN elephant brings the numerous blood vessels among every broad ear into contact with the air, that cools the blood before it circulates once more through the body. This cooling mechanism could explain why the african elephant, that evolved during a hot climate, has ears larger than those of its Asian relative, that evolved during a cooler area. AN elephants tail is bald-pated but contains a lean brush at its tip, a useful gizmo for whisking away irritating flies. A typical tail will weigh ten kilograms (22 lb).
Elephant seeing is poor, and therefore the eyes square measure little in respect to the enormous head, which can turn just slightly from facet to facet. This limited movement leads to restricted facet vision, ANd an elephant must move its whole body to broaden its range of vision. Its alternative senseshearing, smell, taste, and touchare acute. the most sensitive organ is the trunk, that is often at work picking up scents of food and danger from the bottom and air. Elephants will smell water at nice distances and might hear bound sounds from more than a mile away.


Elephants dine on a wealth of plant partsleaves, twigs, bark, shoots, fruit, flowers, roots, tubers, and bulbsfrom as several as eighty completely different plant species. They use their trunks for uprooting clumps of grass and for plucking branches and leaves from shrubs and trees. Hungry African elephants could apply their full weight to a stem, esurient all edible elements once the tree has toppled. Wild Asian elephants eat more grasses, including rice, than their African cousins do; Southeast Asian rice farmers must defend their crops from elephant herds on the move.
The systema digestorium of elephants is less economical than those of alternative herbivores such as antelope and buffalo. Food passes quickly through the systema digestorium before nutrients square measure absorbed, inflicting elephants to discard regarding [*fr1] the material they consume. This inefficient systema digestorium means elephants must eat giant quantities of food to retain and absorb necessary nutrients for good health.
In the wild, elephants devote regarding three-quarters of their day to feeding. AN adult elephant grub 75 to 150 weight unit (165 to 330 lb) of food day by day. Records of zookeepers in the u. s. show that the typical elephant in captivity grub regarding thirty-nine weight unit (about eighty seven lb) of hay; 5 to seven weight unit (10 to 15 lb) of grain; and 5 to seven weight unit (10 to 15 lb) of carrots in twenty four hours. Elephants in captivity are keen on apples, cabbages, and alternative fruits and vegetables.

Reproduction
@_@@_@@_@ual maturity among bulls begins at regarding eleven to 12 years, but throughout sex activity season older bulls drive the younger ones away; bulls typically don't mate until around age 30. once a bull is regarding twenty to twenty five years getting on, the big glands on both sides of its head begin to swell ANd secrete an oily, testosterone-rich fluid. The bull's behavior becomes erratic and infrequently aggressive toward alternative bulls and humans at this point. This event, referred to as stage, happens annually throughout the bulls life, lasting for several days or several months counting on the animal's age and overall health. Scientists square measure uncertain of musths full significance, but several believe it is related to the social hierarchy among bulls that controls access to cows throughout the sex activity season.
Cows begin breeding at regarding 9 years getting on and typically acquire heat, or heat, each sixteen weeks, at which period they are receptive to sex activity. while pregnant, a cows heat cycle halts and she or he does not mate. before long once a cow provides birth, her heat cycle begins once more and she or he mates even though she is nursing. there is no breeding season for elephantsmating happens throughout the year. Elephants don't mate always. Bulls and cows type temporary pairs before sex activity, and once a short entreaty, the bull mounts the cow from behind, copulating for less than a moment. sex activity could continue for several days. Usually, one bull mates with several cows, guarding them from the advances of alternative bulls.
Cows offer birth to single calves twenty to 22 months once conception, the longest gestation familiar for any animal. Cows could offer birth alone or enclosed by alternative cows. A newborn elephant is regarding one m (about three ft) high and weighs regarding 120 weight unit (about 260 lb). The calf is initially helpless and unable to regulate its leg muscles and trunk. once one to two hours, the calf is able to stand and suckle, obtaining milk from its mothers paired mammary glands, that square measure set between the front legs.
Between 3 and 4 weeks, calves begin to experiment with feeding themselves; it's going to take six months before a calf will master the talent of drinking with its trunk. By

the age of 9 months, calves spend nearly half their time feeding on vegetation. they are weaned at regarding 3 or four years getting on upon the birth of a younger brother or sister. In captivity, cows have borne calves until they are 60 years getting on, at intervals of regarding four years.
One or more allomothers, or "aunts," typically assist in the rearing of a calf, staying close to the calf, as an example, while the mother moves away to forage for food. The more allomothers, the larger the chances of the calf's survival. By age ten, a calf will weigh 900 to 1300 weight unit (2000 to 3000 lb). it will attain most of its height between the ages of twenty and twenty five, but in contrast to alternative mammals, will continue to grow at a slow rate throughout life.

Behavior
Elephants show advanced social behavior, living in tight-knit families that square measure matriarchalthat is, headed by the oldest females. Families square measure composed of sisters, cousins, aunts, and nieces, and their young offspring, and home in size from two to 29 people. These animals could remain together always. If a family becomes large, some females leave to start a replacement herd. The members of a family bathe, forage, and travel as a bunch. family members typically keep among forty six m (150 ft) of the matriarch, maintaining contact with their calls. If they are separated even for a matter of hours, their reunion is marked by AN elaborate greeting ceremony, which incorporates running, rumbling, spinning, trumpeting, defecating, urinating, clicking tusks, and rubbing every others bodies with their heads. The family conjointly defends the young, sick, old, and disabled from predators. once the elder cow during a family dies, succeeding oldest sometimes takes her place as leader.
Young males begin to drift from the family at regarding age six, and bit by bit spend more and more time away, alone or in the company of alternative young males. when they become @_@@_@@_@ually mature they either leave the family for good or square measure driven away by the older females. they may go regarding on their own or be part of alternative males to make bachelor herds, remaining near but operative severally of the female-led family units. Bulls among bachelor herds often battle, though seldom to the death, to determine World Health Organization is boss among their herd.
During their seasonal migrations, several family groups could travel together as a single herd light-emitting diode by the oldest feminine, the matriarch. If a predator threatens, the herd groups together, with the matriarch facing the enemy and therefore the young elephants concealing behind the adults. once danger comes too close, the matriarch charges or leads the herd during a stampede to defeat the enemy.
Elephants communicate with each other through bit, sound, scent, and body @_@@_@@_@@_@@_@@_@@_@@_@. Touching is done chiefly with the trunk, and might range from a cow's light caress of her calf to a disciplinary slap delivered by a matriarch to AN unruly sub-adult male. Shoving, kicking, and rubbing against {each alternative|one another} square measure other ways in which elephants communicate.
Elephants conjointly raise their voices to communicate, trumpeting as a warning or greeting to alternative elephants near . These animals conjointly turn out low-frequency rumbling sounds, which can travel over nice distances, reaching the ears of elephants several kilometers away. Recent analysis indicates that elephants conjointly communicate with infrasound, sounds voiceless to human ears.
Elephant communication includes the secretion of different pheromones in water or dung. These chemical scent signals are often detected by near elephants, or carried by the breeze to elephants at a distance. The secretions of the glands throughout stage conjointly convey scent messages. in addition, information is shared through various body poses.

[align=center]An african elephant, as an example, spreads its ears wide and will flap them while holding its trunk against its body to signal it is near to charge.
Much has been written regarding the emotional lifetime of elephants. Observation of untamed elephants has verified them to be loyal and tender, willing to risk their lives for the sake of others during a family group. Wild elephants are familiar to celebrate births of recent elephants and to grieve and even snivel over the death of a family member. In captivity, elephants will become attached to a selected zookeeper or circus employee, refusing to get together for anyone else.
Elephants square measure a key species in the ecology of forests and savannas. while feeding, they form the environment around them. By feeding greenery high on top of ground, they punch holes through that daylight penetrates, sanctionative low-growing plants to thrive. By uprooting grasses, they turn over the soil, aerating it thus new plants grow to exchange those that square measure ingested. In times of drought, they dig water holes from that alternative wildlife conjointly drink. As they rehearse the dense forests and jungles, elephants clear ways that smaller animals, including humans, can use.

Intelligence
It is troublesome to live the intelligence of any animal, including groups of people. however, there square measure sturdy reasons to believe that elephants square measure capable of upper mental functions than several alternative mammals, including puppies and cats. One indicator is the ease with that elephants will learn tricks or tasks, a side of their intelligence that has been place to use by circus homeowners and mahouts, or trainers, in Asia, several of whom teach their elephants to haul logs or transport travelers.
A young elephant remembers the various ways to food or water marked out by AN older cow, another indicator of intelligence. quizzical behavior, ascertained in primates and alternative animals recognized as highly intelligent, is typical of young elephants, World Health Organization place much energy into games of hide and request, tug of war, and ***. Play provides a young elephant with the social skills needed to live during a relations, while strengthening its muscles ANd improving its coordination for the tasks it carries out as an adult, such as search, bathing, and mating.

Elephants and Humans
For more than 2000 years, Asian elephants are captured and trained to serve folks. African elephants were utilized by Carthaginian general Hannibal to hold his provides across the alps throughout his notable march to beat Rome in the third century. As recently because the sixteenth century, elephants were harnessed and ridden onto the piece of land, and during war II (1939-1945) they were wont to drag heavy military instrumentality up steep, muddy slopes.
Although no longer utilized for warfare, Asian elephants continue to earn their detain geographical region and Asian country. some 13,000 to 16,000 of these animalsroughly twenty five % of the world's wild Asian elephant populationhave been captured and trained to perform a range of tasks. actuation logs out of forests, carrying passengers and freight, and assisting in capturing wild elephants square measure among the numerous jobs requiring intelligence and strength that elephants perform.
Logging tasks specially demand high levels of talent. Initial training of elephants for the timber business could take 3 to 5 years. After that, the elephants square measure severally fine-tuned for another 10 years before they are sent resolute haul logs from the forests. The graduates of work colleges may go for 30 years or more, retiring at regarding 50 years getting on. The elephant's trainer (called AN oozie or mahout) earns his living by charging cash to be used of his skilled elephant. The trainer typically grows


[align=center]old beside his student, throughout which period AN unbreakable bond of mutual respect and genuine relationship forms between the two.

Status
African and Asian elephants square measure currently endangered species. a range of forces have contributed to their decline. Elephants are slaughtered in past centuries solely for their tusks, that square measure manufactured from highly prized ivory. in the decade the wild elephant population stood at 5 million to ten million; by one979 hunting and surround destruction had reduced it to 1.3 million. in the 10 years between 1979 and 1989, the collapse of oil prices generated pursuit of alternative moneymaking ventures, ANd an estimated 600,000 African elephantsalmost [*fr1] the populationwere slaughtered for ivory.
In June 1989 the u. s. illegal all ivory imports, with alternative nations adopting similar bans before long thereafter

. under the african elephant Conservation Act, the u. s. established a program to award up to $5 million a year for comes to assist stop the killing of elephants in Africa. Even with such protective measures in situ, ivory cookery remains a serious threat. Poachers kill older elephants, including matriarchs, for their larger tusks. Herds rely on the matriarch, and her loss could interfere with the herds ability to migrate for food and protect the young. once mother elephants square measure killed, the nursing young typically don't survive.
Battles over shared land and its resources conjointly cause several elephant deaths in both Africa and Asia. Increasing population and displacement ensuing from forces such as consolidation of little farms drive folks to clear jungles and forests for new farmland and homes. In a shot to make sure their own survival, folks rob elephants of opportunities to thrive and reproduce. In several countries, wild elephants will solely be found among national parks, several of that square measure too little and isolated to support the growth of herd populations. As a result of human impact and limited success in preserving their habitats, the number of African and Asian elephants has born to a dangerous low.
Elephant researchers, wildlife managers, and conservationists all over the planet square measure presently cooperating to make sure the survival of African and Asian elephants in the wild. Among the more active organizations square measure the planet wildlife Fund and therefore the World Conservation Union (IUCN). Zoos are dedicated to promoting elephant survival, providing needed academic programs regarding this splendid animal and its plight. The yankee zoo and tank Association has established captive breeding programs for Asian and African elephants in a shot to forestall their extinction. Transporting elephants from the wild to zoo populations is currently black, and if breeding programs square measure unsuccessful, the captive elephant population is projected to die out by the year 2030.
Scientific classification: African and Asian elephants square measure members of the elephant family, mammal family, in the animal order. The african elephant is classed as elephant and therefore the Asian elephant as elephant

06-29-2014, 02:46 AM
cool topic