22 August 2008

PEAFOWL


The PEAFOWL can refer to the two species of bird in the genus Pavo of the pheasant family, Phasianidae. The African Congo Peafowl is placed in its own genus Afropavo and is not dealt with here. Peafowl are best known for the male's extravagant tail, which it displays as part of Courship. The male is called a peacock, the female a peachen, though it is common to hear the female also referred to as a "Peacock". The female peafowl is brown or toned grey and brown.
The two species are :
  • Indian Peafowl, pavo cristatus (asiatic)
  • Green Peafowl, pavo muticus (asiatic)

The Indian Peafowl is a resident breeder in indian subcontinent. The peacock is designated as the national bird in India.


The Green Peafowl breeds from Burma east to java. The IUCN lists the Green Peafowl as vulnerable to extinction due to hunting and a reduction in extent and quality of habitat.

Taxonomy

The indian Peafowl is monotypic, while the Green Peafowl has 3 subspecies, P.muticus spicifer, P.imperator and the nominate P.m.muticus. The two species are largely allopatric but will hybridize in captivity.
While the form of Green Peafowl in Yunnan is not separated taxonomically, it differs in few aspects from other forms, particularly in its forest-dwelling habits, an "odd, monal-like bill", a curiously long hind toe and longer, more slander wings (K.B. Woods in litt. 2000). some have suggested this is a new subspecies.
Some pheasant breeders have suggested that the Green Peafowl may have more subspecies. Peafowl have sometimes been included in a distinct family from Pheasant.


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12 August 2008

BUNGLON



Bronchocela jubata, or more commonly known as the Green Crested Lizard, is an agamid lizard found in Indonesia on the island of Singkep, Java, Bali, Sulawesi, karakelang, Salibabu; Nias island, Singkap island, Borneo (kalimantan) and the Philiphines. Although in the past it was thought the species may be found in India, either on the mainland or in the Nicobars, this is not the case according to herpetologist Indranell Das. It is also be known by the name of "bloodsucjker", although this is a misnomer.

Description
The Green Crested Lizard is 55omm in length, with a long hanging tail making up four fifth of its length. It has a jagged crest on its neck which more closely resemble hairs, as opposed to the crest of its close relative, B.cristatella, which more closely resembles the points on a crown. The crest consists of elongated scales, although it is flabby like skin The head is square in shape, and there is a soft sack under the chin. It has large, lfexible eyelids made of fine speckled scales. The dorsal area is coloured from light green to dark green, and can charge to brown or black if felling threatened. A rusty coloured stain appears under the throat. More sport, often blurring to form a stripe, appear on the shoulder and the front lateral side. Towards the back of the lizard, the colour becomes duller. The underside of the lizard is yellowish to white under the chin, neck, stomach and the back of the legs. The Bottom of the hands and tfeet are a yellowish brown. The tail is coloured green at its base, with bluish stains. Towards the end of the tail, the colour becomes a dull brown with whitist spots on the tip. The scales of the Green Crested Lizard are hard, course and strong. The tail has an angular feel.

Taxonomic Diagnosis
Head-scales above rather large, keeled, almost equal; two or three compressed scales behind the supraciliary edge; tympanum large, half or more than half the diameter of the orbit. Nine or ten upper and eight or nine lower labials; a row of slightly enlarged scales on each side of the chin parallel to the labials. A gular sac, with large keeled scales; no fold in front of the shoulder. Nuchal crest large, its spines falciform and directed backwards, the longest about as long as the diameter of the orbit; some rows of smaller spines at the base. Body strongly compressed, covered with large, keeled scales, 43 - 45 round the middle of the body; the scales of the first row next to the dorsal crest pointing upward, those of the second row pointing straight backwards, the others downwards; dorsal crest less developed than nuchal, diminuating backwards. Ventral scales largest of all, strongly keeled. Tail very long, round, slightly compressed at the base and witha slight ridge there. Limbs long, the hind limb nearly reaches the nostril; digits long, third and fourth fingers equal, fifth toe much shorter than third. Green above, with yellow or red spots or bands. Length of head and body 130 mm; tail 440mm.



Habits
The Green Crested Lizard is generally to be found in low or hidden in dense trees. It can frequently be seen having fallen from the bushes or trees while chasing its prey, altough it will quickly run back into the security of the nearest bust or tree. The lizard preys on butterflies, moths, dragonflies, files and other small insect. To catch its prey, the Green Crested Lizard will generally wait in silence at the top of the tree, or it will rock slowly back and forth as if swaying in th breeze. It can also frequently be found utilising domestic electricity cables to cross from one place to another. The Green Crested Lizard lays its eggs in loose earth, sand or humus. Like most members of the agamidae, the mother lizard excavates the earth to form a hollow for the eggs with her snout. The eggs are white, waxy, and leathery in texture. A study cariied out in the Situgede jungle, near Bogor, noted that the eggs of the Green Crested Lizard were buried in dandy soil beneath a layer of humus, directly beneath bushes in fairly open part of the forest. The two eggs were elongated, approximately 7 x 40mm in length, placed side by side, and covered by a thin layer of soil. in walat mountain, Sukabumi, there were eggs covered by a thin layer of humus in the middle of the jungle path.



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02 August 2008

JALAK BALI

The Bali Starling, Leucopsar rothschildi, also known as Rothschild's Mynah, Bali Myna or Bali Mynah is a medium-sized (up to 25Cm long), stocky myna, almost wholly white a long, drooping crest, and black tips on the wings and tail. The bird has blue bare skin around the eyes, greyish legs and a yellow bill. Both sexes are similiar.

Distribution
The Bali Starling is distributed and endemic to the island of Bali in Indonesia, where it is the island's only suviving endemic species. This rare bird was discovered in 1910. The Other Bali's endemic, the Bali Tiger, was declared extinct in 1937. In 1991, the Bali Starling was designated the fauna symbol of Bali; its local name is kedis putih.

Endangered
The Bali Starling is criticaly endangered, hovering immediately above extinction in the wild for saveral years now (BirdLife International 2006). The last stronghold of the species is at Bali Barat National Park; about 1,000 individuals are believed to be held in captivity legally. In fact, th Bali Starling's survival. The wild population was at an all-time low of just 6 birds in 2001, after the late-1990s wild population of 3-4 dozen was reduced by poachers for the illegal pet trade.
Its decline toward extinctionhas been by the urbanization of the island and illegal trapping for the caged-bird trade; indeed, the number of captive birds bought on black market is estimated to be twice the number of legally-acquired individuals in the captive breeding program. The Bali Starling is listed in Appendix I of CITES. Trade even in the captive-bred specimens is strictly regulated and the species is not generally available legally to private individuals. However, experienced aviculturalists may become affiliated with the captive-breeding program, allowing them to legally keep this species.

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29 July 2008

SEA TURTLE


SEA TURLES (Superfamily Chelonioidae) are turles found in all the world's oceans except the Arctic Ocean. There are seven living species of sea turtles: flatblack, green, hawksbil, kemp's ridley, leatherback, loggerhead and olive ridley. The East Pacific subpopulation of green turle was previously classified as a separate species, the black turle, but DNA evidence indicatesthat it is not evolutionarily distinct from the green turtle. all species except the leatherbackare in the family Cheloniidae; the leatherback belongs to the family Dermochelyidae and is its only member.

Anatomy
Although they have been around for tens of milions of year since the mesozoic, the body plan of sea turtles has remained relatively constant. Sea turtles possess dorsoventrally-flattened bodies with two hind legs and highly-evolved pddle-like front arms. Sea turles are one of the oly reptiles witha hard shell. Their shells are made of solid bone covered by large, thin scales, and they protect the whole of animal's body with the exception of the head, legs and tail. However, to make up for that vulnerability, they have the ability to pull their heads inside their shells when threatened. Many can also pull their legs and tail into their shell. Sea turtle flippers are highly evolved; some species of sea turtles can even climb rocky shores with their adapted flippers for their advantage to elude predators. Different species are distinguished varying anatomical aspects: forintance, the prefrontal scales on the head, the number of and shape of scutes on the carapace, and the type of inframarginal scutes on the plastron. The leatherback is the only sea turtle that does not have a hard shell, instead carrying a mosaic of bony plates beneath its leathery skin. It is the largest of the sea turles, measuring six or seven feet (2 m) in length at maturity, and three to five feet (1 to 1.5 m) in width, weighing up to 1300 pounds (650 Kg). Other Species are smaller, being mostly two to four feet in length (0.5 to 1 m) and proportionally narrower.

Distribution
The superfamily cheloinoidea has a world wide distribution, sea turtles can be faund in all oceans except for in the polar regions. Some species travel between oceans. The flatback turtle is faund solely on the northern coast of Australia.

Conservation



All species of sea turtle are endangered.The leatherback, kemp's ridley, and hawksbill turtles are listed as critically endangered. The olive ridley and green turtles are considered endangered, and the longgerhead is a threatened species. The flatback's conservation status is unclear due to a lack of research data.
Sea turtles usesd to be hunted on a large scale in whaling days their meat, fat and shells. Coastal peoples have also been known to gather turtle eggs for consumption. One of their most significant threats now comes from bycatch due various fishing methods, long-line fishing has been blamed as one of causes of accidental sea turtle deaths, and the black market demand for tortoiseshell for both decoration and supposed health benefits.
Nets used in shrimp trawling nad fishing have been known to cause the accidental deaths of sea turtles. The turtles, as air-breathing reptiles, must surface to breathe. Cought in fisherman's net, they are unable to go to the surface to breathe and suffocate to death in the net. early 2007, almost a thousand sea turtles were killed inadvertently in Bay of Bengal over the course of a few months as result of becoming trapped in fishing nets.


However some relatively inexpensive changes to fishing techniques, such as shlightly larged hooks and traps from which sea turtles can escape, can dramatically cut the mortality rate. Turtle Excluder Devices (TEDS) have reduced sea turtle bycatch in shrimp net by 97 percent. Another danger comes from marine debris, especially from abandoned fishing nets in which they can become entangled.
Beach development is another area which poses threats to sesa turtles. SInce sea turtles return to the same beach locations to nest, if these areas are developed they may be left with nowhere to nest, or their nesting locations may be threatened by human activity. Therefore, there has been a movement to protect these areas, in some cases by special police. In some areas, such as the east coast of Florida, after the adult turtles lay their eggs, they are dug up and relocated to special fenced nurseries where they can be protected from beach traffic. this is not the best thing to do, as many turtle species return to the beach on which they were born. Hatchlings find their way to the ocean by crawling towards the brightest horizon, but often become disoriented on developed stretches of coastline. special lighting ordinances may also be enforced to prevent light sining on the beach and confusing young hatchling, causing them to the crawl towards the light and a away from water, usually crossing a road. A turtle-safe lighting system uses red light in place of white light as sea turtles can't see red light.


Another major threat to sea turtles is the black market trade in aggs and meat. this is a pervasive problem throughout the world, but especially a concern in the, Philippines, Indonesia, India and throughout the costal nations of latin America. Estimates are high as 35,000 turtles killed a year in Mexico and the same nurber in Nicaragua. Conservationists In Mexico and a United States have launched "Don't Eat Sea Turtle" campaigns in order to reduce the urban black market trade in sea turtle products. these campigns have involved figures such as Pope John Paul II, Dorismar, Los Tigres Del Norte and Mana. Sea are reptiles, not fish. Conservation organizations have written letters to the Pope asking that he declare turtle meat.
Moreover, global warning can also cause a threat to sea turtles. Since temperatures in the sands define the sex of the turle while developing in the egg, many feared rising temperatures worls only produce one sex, but more research remaind to be done in order to understand how climate change might affect sea turtle gender distribution.
Sea turtle can also be effected by Fibropapillomatosis, a disease that has been found amongst sea turtle populations and causes tumors.
Injured sea turtles are sometimes able to be rescued and rehabilitated by professional organizations such as the Mote Marine Laboratory in sarasota, Florida, the Marine Mammal Center in Northen California, and the ClearWater in South Padre Island, TX. one such turtle, named Nickel for coin that was found lodged in her throat, lives at the Shedd Aquarium in Chicago.
On September,2007 Corpus Christi, Texas wildlife officials found a record of 128 Kemp's ridley sea turtle nests on Texas beaches, including 81 on North Padre Island (Padre Island National Seashore) and 4 on Mustang Island. Wildlife offcials released 10,594 Kemp's ridley hatchling along the texas coast this year. The turtles are endangered due to shrimpers' nets and they are popular in Mexico as boot material and food.
In 2007, the U.S. Fish and Wildlife Service and National Marine fisheries service finished a joint study assessing the worldwide populations of all sea turtle species. It was determined that leatherback, the hawksbill and the Kemp's Ridley populations were endangered while that of green turtles and olive ridleys were threatened.
In Southeast Asia, the Philippines has had several initiatives dealing with the issue of turle conservation. in 2007, the province of Batangas in the Philippines declared the catching and eating of Pawikans illegal. However, the law seems to have little effect as pawikan eggs are still in demand in batangan markets.



Today, one can easily purchase three Pawikan eggs for a more PhP20. on january 23, 2008 the Coastal Resource Management Coordinator arrested and detained fisherman Israel Jimenez,40 from Poblacion, Bacuag, Surigao del Norte who slaughtered and endangered sea turtle, pending the filling of case by The Bereau of Fisheries and Aquatic Resaurces.
In September of 2007, several chinese poachers were apprehended off the Turtle Island in the country's southernmost province of Tawi-Tawi. The poachers were discovered to have collected more than a hundred sea turtles, along with 10,000 turtle eggs.

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26 July 2008

KOMODO DRAGON



Kingdom : Animalia

Phylum : Chordata

Class : Reptilia

Order : Squamata

Suborder : Scleroglossa

Family : Varanidae

Genus : Varanus

Species : V. komodoensis

Binomial name

Varanus komodoensis


The Komodo dragon (Varanus komodoensis) is a species of lizard that inhabits the islands of Komodo, Rinca, Flores, Gili Motang, and Gili Dasami, in central Indonesia. A member of the monitor lizard family (Varanidae), it is the largest living species of lizard, growing to an average length of 2-3 meters (approximately 6.5-10 ft) and weighing around 70 kilograms (154 lb). Their unusual size is attributed to island gigantism, since there are no other carnivorous animals to fill the niche on the islands where they live, and also to the Komodo dragon's low metabolic rate. As a result of their size, these lizards are apex predators, dominating the ecosystems in which they live. Although Komodo dragons eat mostly carrion, they will also hunt and ambush prey including invertebrates, birds, and mammals.

Mating begins between May and August, and the eggs are laid in September. About twenty eggs are deposited in abandoned megapode nests and incubated for seven to eight months, hatching in April, when insects are most plentiful. Young Komodo dragons are vulnerable and therefore dwell in trees, safe from predators and cannibalistic adults. They take around three to five years to mature, and may live as long as fifty years. They are capable of parthenogenesis, in which viable eggs are laid without fertilization by a male.

Komodo dragons were discovered by Western scientists in 1910. Their large size and fearsome reputation makes them popular zoo exhibits. In the wild their range has contracted due to human activities and they are listed as vulnerable by the IUCN. They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.

The Komodo dragon is also known as the Komodo Monitor or the Komodo Island Monitor in scientific literature, although this is not very common. To the natives of Komodo Island, it is referred to as ora, buaya darat (land crocodile) or biawak raksasa (giant monitor).


Evolution

The evolutionary development of the Komodo dragon started with the Varanus genus, which originated in Asia about 40 million years ago and migrated to Australia. Around 15 million years ago, a collision between Australia and Southeast Asia allowed the Varanids to move into what is now the Indonesian archipelago. The Komodo dragon is believed to have differentiated from its Australian ancestors 4 million years ago, extending their range to as far east as the island of Timor. The Ice Age and its dramatic sea level changes brought the islands that the Komodo dragons inhabited into their present locations, isolating them in their present range.


Description

In the wild, an adult Komodo dragon usually weighs around 70 kilograms (154 lb), although captive specimens often weigh more. The largest verified wild specimen was 3.13 meters (10 ft 3 in) long and weighed 166 kilograms (365 lb), including undigested food. The Komodo dragon has a tail as long as its body, as well as about 60 frequently-replaced serrated teeth that can measure up to 2.5 centimeters (1 inch) in length. Its saliva is frequently blood-tinged, because its teeth are almost completely covered by gingival tissue that is naturally lacerated during feeding. This creates an ideal culture for the virulent bacteria that live in its mouth. It also has a long, yellow, deeply-forked tongue.


Senses

The Komodo dragon does not have a particularly acute sense of hearing, despite its visible earholes, and is only able to hear sounds between 400 and 2000 hertz. It is able to see as far away as 300 meters (985 feet), but because its retinas only contain cones, it is thought to have poor night vision. The Komodo dragon is able to see in color, but has poor visual discrimination of stationary objects.

The Komodo dragon uses its tongue to detect taste and smell stimuli, as with many other reptiles, with the vomeronasal sense using a Jacobson's organ, a sense that aids navigation in the dark. With the help of a favorable wind and its habit of swinging its head from side to side as it walks, Komodo dragons may be able to detect carrion from 4-9.5 kilometres (2.5-6 mi) away. The dragon's nostrils are not of great use for smelling, as the animal does not have a diaphragm. It only has a few taste buds in the back of its throat. Its scales, some of which are reinforced with bone, have sensory plaques connected to nerves that facilitate its sense of touch. The scales around the ears, lips, chin, and soles of the feet may have three or more sensory plaques.

The Komodo dragon was formerly thought to be deaf when a study reported no agitation in wild Komodo dragons in response to whispers, raised voices, or shouts. This was disputed when London Zoological Garden employee Joan Proctor trained a captive specimen to come out to feed at the sound of her voice, even when she could not be seen.


Ecology

The Komodo dragon prefers hot and dry places, and typically lives in dry open grassland, savanna, and tropical forest at low elevations. As an ectotherm, it is most active in the day, although it exhibits some nocturnal activity. Komodo dragons are largely solitary, coming together only to breed and eat. They are capable of running rapidly in brief sprints up to 20 kilometres per hour (12.4 mph), diving up to 4.5 metres (15 ft), and climbing trees proficiently when young through use of their strong claws. To catch prey that is out of reach, the Komodo dragon may stand on its hind legs and use its tail as a support. As the Komodo dragon matures, its claws are used primarily as weapons, as its great size makes climbing impractical.

For shelter, the Komodo dragon digs holes that can measure from 1-3 metres (3-10 ft) wide with its powerful forelimbs and claws. Because of its large size and habit of sleeping in these burrows, it is able to conserve body heat throughout the night and minimize its basking period the morning after. The Komodo dragon typically hunts in the afternoon, but stays in the shade during the hottest part of the day. These special resting places, usually located on ridges with a cool sea breeze, are marked with droppings and are cleared of vegetation. They also serve as a strategic location from which to ambush deer.


Diet

Komodo dragons are carnivores. Although they eat mostly carrion, they will also ambush live prey with a stealthy approach. When suitable prey arrives near a dragon's ambush site, it will suddenly charge at the animal and go for the underside or the throat. It is able to locate its prey using its keen sense of smell, which can locate a dead or dying animal from a range of up to 9.5 kilometers (6 miles). Komodo dragons have also been observed knocking down large pigs and deer with their strong tail.

Komodo dragons eat by tearing large chunks of flesh and swallowing them whole while holding the carcass down with their forelegs. For smaller prey up to the size of a goat, their loosely articulated jaws, flexible skull, and expandable stomach allow it to swallow its prey whole. The vegetable contents of the stomach and intestines are typically avoided. Copious amounts of red saliva that the Komodo dragons produce helps to lubricate the food, but swallowing is still a long process (15-20 minutes to swallow a goat). Komodo dragons may attempt to speed up the process by ramming the carcass against a tree to force it down its throat, sometimes ramming so forcefully that the tree is knocked down. To prevent itself from suffocating while swallowing, it breathes using a small tube under the tongue that connects to the lungs. After eating up to 80 percent of its body weight in one meal, it drags itself to a sunny location to speed digestion, as the food could rot and poison the dragon if left undigested for too long. Because of their slow metabolism, large dragons can survive on as little as 12 meals a year. After digestion, the Komodo dragon regurgitates a mass of horns, hair, and teeth known as the gastric pellet, which is covered in malodorous mucus. After regurgitating the gastric pellet, it rubs its face in the dirt or on bushes to get rid of the mucus, suggesting that it, like humans, does not relish the scent of its own excretions.

The largest animals generally eat first, while the smaller ones follow a hierarchy. The largest male asserts his dominance and the smaller males show their submission by use of body language and rumbling hisses. Dragons of equal size may resort to "wrestling." Losers usually retreat, though have been known to be killed and eaten by victors.

The Komodo dragon's diet is wide-ranging, and includes invertebrates, other reptiles (including smaller Komodo dragons), birds, bird eggs, small mammals, monkeys, wild boars, goats, deer, horses, and water buffalos. Young Komodos will eat insects, eggs, geckoes, and small mammals. Occasionally they have been known to consume humans and human corpses, digging up bodies from shallow graves to do so. This habit of raiding graves caused the villagers of Komodo to move their graves from sandy to clay ground and pile rocks on top of them to deter the lizards. The Komodo dragon may have evolved to feed on the extinct dwarf elephant Stegodon that once lived on Flores, according to evolutionary biologist Jared Diamond. The Komodo dragon has also been observed intentionally startling a pregnant deer in the hopes of a miscarriage whose remains they can eat, a technique that has also been observed in large African predators.

Because the Komodo dragon does not have a diaphragm, it cannot suck water when drinking, nor can it lap water with its tongue. Instead, it drinks by taking a mouthful of water, lifting its head, and letting the water run down its throat.


Venom and Bacteria

In late 2005, University of Melbourne researchers concluded that the Perentie (Varanus giganteus), other species of monitor, and agamids may be somewhat venomous. It had been thought that bites inflicted by these lizards were prone to infection because of bacteria in the lizards' mouths, but the research team showed that the immediate effects were caused by mild envenomation. Bites on human digits by a Lace Monitor (V. varius), a Komodo dragon, and a Spotted Tree Monitor (V. scalaris) were observed, and all produced similar results in humans: rapid swelling within minutes, localized disruption of blood clotting, shooting pain up to the elbow, with some symptoms lasting for several hours.

Komodo dragons also possess virulent bacteria in their saliva, of which more than 28 Gram-negative and 29 Gram-positive strains have been isolated. These bacteria cause septicemia in their victim; if an initial bite does not kill the prey animal and it escapes, it will commonly succumb within a week to the resulting infection. The deadliest bacteria in Komodo dragon saliva appears to be a very deadly strain of Pasteurella multocida, from studies performed with lab mice. Because the Komodo dragon appears immune to its own microbes, much research has been done searching for the antibacterial molecule in the hopes of human medicinal use.


Reproduction

Mating occurs between May and August, with the eggs laid in September. During this period, males fight over females and territory by grappling with one another upon their hind legs with the loser eventually being pinned to the ground. These males may vomit or defecate when preparing for the fight. The winner of the fight will then flick his long tongue at the female to gain information about her receptivity. Females are antagonistic and resist with their claws and teeth during the early phases of courtship. Therefore, the male must fully restrain the female during coitus to avoid being hurt. Other courtship displays include males rubbing their chins on the female, hard scratches to the back, and licking. Copulation occurs when the male inserts one of his hemipenes into the female's cloaca. Komodo dragons may be monogamous and form "pair bonds", a rare behavior for lizards

The female lays her eggs in burrows cut into the side of a hill or in the abandoned nesting mounds of the Orange-footed Scrubfowl (a moundbuilder or megapode), with a preference for the abandoned mounds. Clutches contain an average of 20 eggs which have an incubation period of 7-8 months. The female lies on the eggs to incubate and protect them until they hatch around April, at the end of the rainy season when insects are plentiful. Hatching is an exhausting effort for the pups, who break out of their eggshells with an egg tooth that falls off soon after. After cutting out the hatchlings may lie in their eggshells for hours before starting to dig out of the nest. They are born quite defenseless, and many are eaten by predators.

Young Komodo dragons spend much of their first few years in trees, where they are relatively safe from predators, including cannibalistic adults, who make juvenile dragons 10% of their diet. According to David Attenborough, the habit of cannibalism may be advantageous in sustaining the large size of adults, as medium-sized prey on the islands is rare. When the young must approach a kill, they roll around in fecal matter and rest in the intestines of eviscerated animals to deter these hungry adults. Komodo dragons take about three to five years to mature, and may live for up to 50 years.


Parthenogenesis

A Komodo dragon at London Zoo named Sungai laid a clutch of eggs in late 2005 after being separated from male company for more than two years. Scientists initially assumed that she had been able to store sperm from her earlier encounter with a male, an adaptation known as superfecundation. On December 20, 2006, it was reported that Flora, a captive Komodo dragon living in the Chester Zoo in England, was the second known Komodo dragon to have laid unfertilized eggs: she laid 11 eggs, and 7 of them hatched, all of them male. Scientists at Liverpool University in northern England performed genetic tests on three eggs that collapsed after being moved to an incubator, and verified that Flora had had no physical contact with a male dragon. After Flora's eggs' condition has been discovered, testing showed that Sungai's eggs were also produced without outside fertilization.

Komodo dragons have the ZW chromosomal sex-determination system, as opposed to the mammalian XY system. Male progeny prove that Flora's unfertilized eggs were haploid (n) and doubled their chromosomes later to become diploid (2n) means of a polar body, rather than it being the case that she laid diploid eggs (as would have happened if one of the meiosis reduction-divisions in her ovaries had failed). When a female Komodo dragon (with ZW sex chromosomes) reproduces in this manner, she provides her progeny with only one chromosome from each of her pairs of chromosomes, including only one of her two sex chromosomes. This single set of chromosomes is duplicated in the egg, which develops parthenogenetically. Eggs receiving a Z chromosome become ZZ (male); those receiving a W chromosome become WW and fail to develop.

It has been hypothesized that this reproductive adaptation allows a single female to enter an isolated ecological niche (such as an island) and by parthenogenesis produce male offspring, thereby establishing a sexually reproducing population (via reproduction with her offspring that can result in both male and female young). Despite the advantages of such an adaptation, zoos are cautioned that parthenogenesis may be detrimental to genetic diversity.

On January 31, 2008, the Sedgwick County Zoo in Wichita, Kansas became the first zoo in the Americas to document parthenogenesis in Komodo dragons. The zoo has two adult female Komodo dragons, one of which laid about 17 eggs on May 19-20, 2007. Only two eggs were incubated and hatched due to space issues; the first hatched on January 31, 2008 while the second hatched on February 1. Both hatchlings were males.


History

Discovery by the western world

Komodo dragons were first documented by Europeans in 1910, when rumors of a "land crocodile" reached Lieutenant van Steyn van Hensbroek of the Dutch colonial administration. Widespread notoriety came after 1912, when Peter Ouwens, the director of the Zoological Museum at Bogor, Java, published a paper on the topic after receiving a photo and a skin from the lieutenant, as well as two other specimens from a collector. Later, the Komodo dragon was the driving factor for an expedition to Komodo Island by W. Douglas Burden in 1926. After returning with 12 preserved specimens and 2 live ones, this expedition provided the inspiration for the 1933 movie King Kong. It was also Burden who coined the common name "Komodo dragon." Three of his specimens were stuffed and are still on display in the American Museum of Natural History.

Studies

The Dutch, realizing the limited number of individuals in the wild, outlawed sport hunting and heavily limited the number of individuals taken for scientific study. Collecting expeditions ground to a halt with the occurrence of World War II, not resuming until the 1950s and 1960s, when studies examined the Komodo dragon's feeding behavior, reproduction, and body temperature. At around this time, an expedition was planned in which a long-term study of the Komodo dragon would be undertaken. This task was given to the Auffenberg family, who stayed in Komodo Island for 11 months in 1969. During their stay, Walter Auffenberg and his assistant Putra Sastrawan captured and tagged more than 50 Komodo dragons. The research from the Auffenberg expedition would prove to be enormously influential in raising Komodo dragons in captivity. Research after the Auffenberg family has shed more light on the nature of the Komodo dragon, with biologists such as Claudio Ciofi continuing to study the creatures.


Conservation

The Komodo dragon is a vulnerable species and is found on the IUCN Red List. There are approximately 4,000-5,000 living Komodo dragons in the wild. Their populations are restricted to the islands of Gili Motang (100), Gili Dasami (100), Rinca (1,300), Komodo (1,700), and Flores (perhaps 2,000). However, there are concerns that there may presently be only 350 breeding females. To address these concerns, the Komodo National Park was founded in 1980 to protect Komodo dragon populations on islands including Komodo, Rinca, and Padar. Later, the Wae Wuul and Wolo Tado Reserves were opened on Flores to aid with Komodo dragon conservation. There is evidence that Komodo dragons are becoming accustomed to human presence, as they are often fed animal carcasses at several feeding stations by tourists.

Volcanic activity, earthquakes, loss of habitat, fire (the population at Padar was almost destroyed because of a wildfire, and has since mysteriously disappeared), loss of prey, tourism, and poaching have all contributed to the vulnerable status of the Komodo dragon. Under Appendix I of CITES (the Convention on International Trade in Endangered Species), commercial trade of skins or specimens is illegal.

In capacity

Komodo dragons have long been great zoo attractions, where their size and reputation make them popular exhibits. They are, however, rare in zoos because they are susceptible to infection and parasitic disease if captured from the wild, and do not readily reproduce.

The first Komodo dragon was exhibited in 1934 at the Smithsonian National Zoological Park, but it lived for only two years. More attempts to exhibit Komodo dragons were made, but the lifespan of these creatures was very short, averaging 5 years in the National Zoological Park. Studies done by Walter Auffenberg, which were documented in his book The Behavioral Ecology of the Komodo Monitor, eventually allowed for more successful managing and reproducing of the dragons in captivity.

It has been observed in captive dragons that many individuals display relatively tame behavior within a short period of time in captivity. Many occurrences are reported where keepers have brought the animals out of their enclosures to interact with zoo visitors, including young children, to no harmful effect. Dragons are also capable of recognizing individual humans. Ruston Hartdegen of the Dallas Zoo reported that their Komodo dragons reacted differently when presented with their regular keeper, a less familiar keeper, or a completely unfamiliar keeper.

Research with captive Komodo dragons has also provided evidence that they engage in play. One study concerned an individual who would push a shovel left by its keeper, apparently attracted to the sound of it scraping across the rocky surface. A young female dragon at the National Zoo in Washington, D.C. would grab and shake various objects including statues, beverage cans, plastic rings and blankets. She would also insert her head into boxes, shoes, and other objects. She did not confuse these objects with food, as she would only swallow them if they were covered in rat blood. This social play has led to a striking comparison with mammalian play.

The Australian biologist Tim Flannery has suggested that Australian ecosystem may benefit from the introduction of Komodo dragons, as it could partially occupy the large-carnivore niche left vacant following the extinction of the giant varanid Megalania. However, he argues for great caution and gradualness in these acclimatisation experiments, especially as "the problem of predation of large varanids upon humans should not be understated". He uses the example of the successful coexistence with saltwater crocodiles as evidence that Australians could successfully adjust.

Although attacks are very rare, Komodo dragons have been known to kill humans. On June 4, 2007, a Komodo dragon attacked an eight year old boy on Komodo Island. He later died of massive bleeding from his wounds. It was the first recorded fatal attack in 33 years.

Another documentation of play in Komodo dragons comes from the University of Tennessee, where a young Komodo dragon named "Kraken" interacted with plastic rings, a shoe, a bucket, and a tin can by nudging them with her snout, swiping at them, and carrying them around in her mouth. She treated all of them differently than her food, prompting leading researcher Gordon Burghardt to conclude that they disprove the view of object play being "food-motivated predatory behavior." Kraken was the first Komodo dragon hatched in captivity outside of Indonesia, born in the National Zoo in September 13, 1992.

Even seemingly docile dragons may become aggressive unpredictably, especially when the animal's territory is invaded by someone unfamiliar. In June 2001, a Komodo dragon seriously injured Phil Bronstein-executive editor of the San Francisco Chronicle-when he entered its enclosure at the Los Angeles Zoo after being invited in by its keeper. Bronstein was bitten on his bare foot, as the keeper had told him to take off his white shoes, which could have potentially excited the Komodo dragon. Although he escaped, he needed to have several tendons in his foot reattached surgically.

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24 July 2008

ORANG UTAN


ORANG UTAN


Kingdom : Animalia

Phylum : Chordata

Class : Mammalia

Order : Primates

Family : Hominidae

Subfamily : Ponginae

Elliot, 1912

Genus : Pongo

Lacépède, 1799

Species : Pongo pygmaeus

Pongo abelii

The orangutans are two species of great apes known for their intelligence, long arms and reddish-brown hair. Native to Indonesia and Malaysia, they are currently found only in rainforests on the islands of Borneo and Sumatra, though fossils have been found in Java, Vietnam and China. They are the only surviving species in the genus Pongo and the subfamily Ponginae (which also includes the extinct genera Gigantopithecus and Sivapithecus). Their name derives from the Malay and Indonesian phrase orang hutan, meaning "man of the forest".The orangutan is an official state animal of Sabah in Malaysia.

Etimology

The word orangutan (also written orang-utan, orang utan and orangutang) is derived from the Malay and Indonesian words orang meaning "man" and hutan meaning "forest", thus "person of the forest". Orang Hutan is the common term in these two national languages, although local peoples may also refer to them by local languages. Maias and mawas are also used in Malay, but it is unclear if those words refer only to orangutans, or to all apes in general.

The word was first attested in English in 1691 in the form orang-outang, and variants with -ng instead of -n as in the Malay original are found in many languages. This spelling (and pronunciation) has remained in use in English up to the present, but has come to be regarded as incorrect by some.

The name of the genus, Pongo, comes from a 16th century account by Andrew Battell, an English sailor held prisoner by the Portuguese in Angola, which describes two anthropoid "monsters" named Pongo and Engeco. It is now believed that he was describing gorillas, but in the late 18th century it was believed that all great apes were orangutans; hence Lacépède's use of Pongo for the genus.

Ecology and Appearance

Orangutans are the most arboreal of the great apes, spending nearly all of their time in the trees. Every night they fashion nests, in which they sleep, from branches and foliage. They are more solitary than the other apes, with males and females generally coming together only to mate. Mothers stay with their babies until the offspring reach an age of six or seven years. There is significant sexual dimorphism between females and males: females can grow to around 4 ft 2 in or 127 centimetres and weigh around 100 lbs or 45 kg, while flanged adult males can reach 5 ft 9 in or 175 centimetres in height and weigh over 260 lbs or 118 kg.

The arms of an orangutan are twice as long as their legs. Much of the arm's length has to do with the length of the radius and the ulna rather than the humerus. Their fingers and toes are curved, allowing them to better grip onto branches. Orangutans have less restriction in the movements of their legs unlike humans and other primates, due to the lack of a hip joint ligament which keeps the femur held into the pelvis. Unlike gorillas and chimpanzees, orangutans are not true knuckle-walkers, and walk on the ground by shuffling on their palms with their fingers

Bimodal Male Development

Adult male orangutans exhibit two modes of physical development, flanged and unflanged. Flanged adult males have a variety of secondary sexual characteristics, including cheek pads (called "flanges"), throat pouch, and long fur, that are absent from both adult females and from unflanged males. Flanged males establish and protect territories that do not overlap with other flanged males' territories. Adult females, juveniles, and unflanged males do not have established territories. A flanged male's mating strategy involves establishing and protecting a territory, advertising his presence, and waiting for receptive females to find him. Unflanged males are also able to reproduce; their mating strategy involving finding females in estrus and forcing copulation. Males appear to remain in the unflanged state until they are able to establish and defend a territory, at which point they can make the transition from unflanged to flanged within a few months. The two reproductive strategies, referred to as "call-and-wait" for flanged male and "sneak-and-rape" for the unflanged male, were found to be approximately equally effective in one study group in Sumatra, though this observation did occur during a period of instability in flanged male rank and unflanged male mating success may be lower in Borneo.

Diet

Fruit makes up 65% of the orangutan diet. Fruits with sugary or fatty pulp are favored. The fruit of fig trees are also commonly eaten since it is easy to both harvest and digest. Other food items include: young leaves, shoots, seeds and bark. Insects and bird eggs are also included.

Orangutans are thought to be the sole fruit disperser for some plant species including the climber species Strychnos ignatii which contains the toxic alkaloid strychnine. It does not appear to have any effect on orangutans except for excessive saliva production.

Behaviour and Language

Like the other great apes, orangutans are remarkably intelligent. Although tool use among chimpanzees was documented by Jane Goodall in the 1960s, it was not until the mid-1990s that one population of orangutans was found to use feeding tools regularly. A 2003 paper in the journal Science described the evidence for distinct orangutan cultures.

According to recent research by the psychologist Robert Deaner and his colleagues, orangutans are the world's most intelligent animal other than humans, with higher learning and problem solving ability than chimpanzees, which were previously considered to have greater abilities. A study of orangutans by Carel van Schaik, a Dutch primatologist at Duke University, found them capable of tasks well beyond chimpanzees' abilities - such as using leaves to make rain hats and leakproof roofs over their sleeping nests. He also found that, in some food-rich areas, the creatures had developed a complex culture in which adults would teach youngsters how to make tools and find food.

A two year study of orangutan symbolic capability was conducted from 1973-1975 by Gary L. Shapiro with Aazk, a juvenile female orangutan at the Fresno City Zoo (now Chaffee Zoo) in Fresno, California. The study employed the techniques of David Premack who used plastic tokens to teach the chimpanzee, Sarah, linguistic skills. Shapiro continued to examine the linguistic and learning abilities of ex-captive orangutans in Tanjung Puting National Park, in Indonesian Borneo, between 1978 and 1980. During that time, Shapiro instructed ex-captive orangutans in the acquisition and use of signs following the techniques of R. Allen and Beatrix Gardner who taught the chimpanzee, Washoe, in the late-1960s. In the only signing study ever conducted in a great ape's natural environment, Shapiro home-reared Princess, a juvenile female who learned nearly 40 signs (according to the criteria of sign acquisition used by Francine Patterson with Koko, the gorilla) and trained Rinnie, a free-ranging adult female orangutan who learned nearly 30 signs over a two year period. For his dissertation study, Shapiro examined the factors influencing sign learning by four juvenile orangutans over a 15-month period.

The first orangutan language study program, directed by Dr. Francine Neago, was listed by Encyclopedia Britannica in 1988. The Orangutan language project at the Smithsonian National Zoo in Washington, D.C., uses a computer system originally developed at UCLA by Neago in conjunction with IBM.

Zoo Atlanta has a touch screen computer where their two Sumatran Orangutans play games. Scientists hope that the data they collect from this will help researchers learn about socializing patterns, such as whether they mimic others or learn behavior from trial and error, and hope the data can point to new conservation strategies.

Although orangutans are generally passive, aggression toward other orangutans is very common; they are solitary animals and can be fiercely territorial. Immature males will try to mate with any female, and may succeed in forcibly copulating with her if she is also immature and not strong enough to fend him off. Mature females easily fend off their immature suitors, preferring to mate with a mature male.

Orangutans have even shown laughter-like vocalizations in response to physical contact, such as wrestling, play chasing, or tickling.

Species

* Genus Pongo

o Bornean Orangutan (Pongo pygmaeus)

+ Pongo pygmaeus pygmaeus - northwest populations

+ Pongo pygmaeus morio - east populations

+ Pongo pygmaeus wurmbii - southwest populations

o Sumatran Orangutan (P. abelii)

The populations on the two isolated islands were classified as subspecies until recently, when they were elevated to full specific level, and the three distinct populations on Borneo were elevated to subspecies. Some suggest that the subspecies wurmbii is conspecific with the Sumatra population (P. abelii). In that case, the resulting species, which would be distributed in Sumatra and southwestern Borneo, would be known as Pongo wurmbii, as that is the older name.[citation needed]

In addition, a fossil species, P. hooijeri, is known from Vietnam, and multiple fossil subspecies have been described from several parts of southeastern Asia. It is unclear if these belong to P. pygmaeus or P. abeli or, in fact, represent distinct species.

Conservation Status

The Sumatran species is critically endangered and the Bornean species of orangutans is endangered according to the IUCN Red List of mammals, and both are listed on Appendix I of CITES. The total number of Bornean orangutans is estimated to be less than 14% of what it was in the recent past (from around 10,000 years ago until the middle of the twentieth century) and this sharp decline has occurred mostly over the past few decades due to human activities and development. Species distribution is now highly patchy throughout Borneo: it is apparently absent or uncommon in the south-east of the island, as well as in the forests between the Rejang River in central Sarawak and the Padas River in western Sabah (including the Sultanate of Brunei). A similar development have been observed for the Sumatran orangutans.

The most recent estimate for the Sumatran Orangutan is around 7,300 individuals in the wild[18] while the Bornean Orangutan population is estimated at between 45,000 and 69,000. These estimates were obtained between 2000 and 2003. Since recent trends are steeply down in most places due to logging and burning, it is forecast that the current numbers are below these figures.

Orangutan habitat destruction due to logging, mining and forest fires, as well as fragmentation by roads, has been increasing rapidly in the last decade. A major factor in that period of time has been the conversion of vast areas of tropical forest to oil palm plantations in response to international demand (the palm oil is used for cooking, cosmetics, mechanics, and more recently as source of biodiesel). Some UN scientists believe that these plantations could lead to the extinction of the species by the year 2012. Some of this activity is illegal, occurring in national parks that are officially off limits to loggers, miners and plantation development. There is also a major problem with hunting and illegal pet trade. In early 2004 about 100 individuals of Bornean origin were confiscated in Thailand and 50 of them were returned to Kalimantan in 2006. Several hundred Bornean orangutan orphans who were confiscated by local authorities have been entrusted to different orphanages in both Malaysia and Indonesia. They are in the process of being rehabilitated into the wild.

Major conservation centres in Indonesia include those at Tanjung Puting National Park in Central Kalimantan, Kutai in East Kalimantan, Gunung Palung National Park in West Kalimantan, and Bukit Lawang in the Gunung Leuser National Park on the border of Aceh and North Sumatra. In Malaysia, conservation areas include Semenggoh Wildlife Centre in Sarawak and Matang Wildlife Centre also in Sarawak, and the Sepilok Orang Utan Sanctuary near Sandakan in Sabah.

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