Animal's Blog

Gibbon

Gibbons are apes in the family Hylobatidae (pronounced /ˌhaɪlɵˈbeɪtɨdiː/). The family is divided into four genera based on their diploid chromosome number: Hylobates (44), Hoolock (38), Nomascus (52), and Symphalangus . The extinct Bunopithecus sericus is a gibbon or gibbon-like ape which, until recently, was thought to be closely related to the Hoolock gibbons. Gibbons occur in tropical and subtropical rainforests from northeast India to Indonesia and north to southern China, including the islands of Sumatra, Borneo and Java.

Also called the lesser apes, gibbons differ from great apes (chimpanzees, bonobos, gorillas, orangutans and humans) in being smaller and (other than most humans) pair-bonded, in not making nests, and in certain anatomical details in which they superficially more closely resemble monkeys than great apes do. Gibbons are masters of their primary mode of locomotion, brachiation, swinging from branch to branch for distances of up to 15 m (50 ft), at speeds as high as 56 km/h (35 mph). They can also make leaps of up to 8 m (27 ft), and walk bipedally with their arms raised for balance. They are the fastest and most agile of all tree-dwelling, non-flying mammals.

Depending on species and gender, gibbons' fur coloration varies from dark to light brown shades, and anywhere in between black and white. It is rare to see a completely white gibbon.


Anatomy

One unique aspect of gibbon physiology is that the wrist is composed of a ball and socket joint, allowing for biaxial movement. This greatly reduces the amount of energy needed in the upper arm and torso, while also reducing stress on the shoulder joint. They also have long hands and feet, with a deep cleft between the first and second digits of their hands. Their fur is usually black, gray, or brownish, often with white markings on hands, feet, and face. Some species have an enlarged throat sac, which inflates and serves as a resonating chamber when the animals call. This structure is enormous in a few species, equaling the size of the animal's head.

Gibbon skulls resemble those of great apes, with very short rostra, enlarged braincases, and large orbits that face forward. Gibbons have the typical nose of catarrhine primates with nostrils that are close together and face forward and slightly downward. They lack cheek pouches and their stomach is not sacculated. Their teeth also are similar to the great apes, with molars that are bunodont and lack lophs. The upper molars usually have a cingulum, which is sometimes large. The canines are prominent but not sexually dimorphic. The dental formula is:
Upper: 2.1.2.3
Lower: 2.1.2.3

Behavior

Gibbons are social animals. They are strongly territorial, and defend their boundaries with vigorous visual and vocal displays. The vocal element, which can often be heard for distances of up to 1 km, consists of a duet between a mated pair, their young sometimes joining in. In most species males, and in some also females, sing solos that attract mates as well as advertise their territory. The songs can make them an easy find for poachers who engage in the illegal wildlife trade and in sales of body parts for use in traditional medicine.

The gibbons' ball-and-socket joints allow them unmatched speed and accuracy when swinging through trees. Nonetheless, their mode of transportation can lead to hazards when a branch breaks or a hand slips, and researchers estimate that the majority of gibbons suffer bone fractures one or more times during their lifetimes.

Status

Most species are threatened or endangered, most importantly from degradation or loss of their forest habitat. Gibbon species include the Siamang, the White-handed or Lar Gibbon, and the hoolock gibbons. The Siamang, which is the largest of the 13 species, is distinguished by having two fingers on each hand stuck together, hence the generic and species names Symphalangus and syndactylus.

Sumatran Tiger



The Sumatran tiger (Panthera tigris sumatrae) is a subspecies of tiger found on the Indonesian island of Sumatra. Recent genetic testing has revealed the presence of unique genetic markers, which isolate Sumatran tigers from all mainland subspecies. Currently, there are only 100-400 Sumatran tigers left in the wild.

Characteristics

The Sumatran Tiger is the smallest of all surviving tiger subspecies. Male Sumatran tigers average 204 cm (6 feet, 8 inches) in length from head to tail and weigh about 136 kg (300 lb). Females average 198 cm (6 feet, 6 inches) in length and weigh about 91 kg (200 lb). Its stripes are narrower than other subspecies of tigers' stripes, and it has a more bearded and maned appearance, especially the males. Its small size makes it easier to move through dense rain forests. It has webbing between its toes that, when spread, makes Sumatran tigers very fast swimmers. It has been known to drive hoofed prey into the water, especially if the prey animal is a slow swimmer.

Sumatran Tigers commonly prey on larger ungulates, like Wild Boar, Malayan Tapir and deer, and sometimes also smaller animals, like fowl, monkeys, and fish. Orangutans could be prey, but since they spend a minimal amount of time on the ground, tigers rarely catch one.

Genetics and evolution

Analysis of DNA is consistent with the hypothesis that the Sumatran Tigers have been isolated after a rise in sea level at the Pleistocene to Holocene border (about 12,000-6,000 years ago) from other tiger populations. In agreement with this evolutionary history, the Sumatran Tiger is genetically isolated from all living mainland tigers, which form a distinct group, closely related among each other.

Habitat
Sumatran Tiger in the Melbourne Zoo

The Sumatran tiger is only found naturally in Sumatra, a large island in western Indonesia. It lives anywhere from lowland forests to mountain forest and inhabits many unprotected areas. Only about 400 live in game reserves and national parks, The largest population of about 110 tigers lives in Gunung Leuser National Park. Another 100 live in unprotected areas that will soon be lost and the rest are spread out in areas that are quickly being lost to agriculture. The reserves are not safe because, despite conservation efforts, many tigers are killed by poachers each year. The Sumatran Tiger is found only on the Indonesian island of Sumatra in habitat that ranges from lowland forest to sub mountain and mountain forest including some peat swamp forests. According to the Tiger Information Centre and the World Wildlife Fund there are no more than 500 of these tigers left in the wild with some estimates considerably lower.

The continuing loss of habitat is intensifying the crises to save this tiger.

Conservation

In 2007, the Indonesian Forestry Ministry and Safari Park established cooperation with the Australia Zoo for the conservation of Sumatran Tigers and other endangered species. The cooperation agreement was marked by the signing of a Letter of Intent on 'Sumatran Tiger and other Endangered Species Conservation Program and the Establishment of a Sister Zoo Relationship between Taman Safari and Australia Zoo' at the Indonesian Forestry Ministry office on July 31, 2007. The program includes conserving Sumatran Tigers and other endangered species in the wild, efforts to reduce conflicts between tigers and humans and rehabilitating Sumatran Tigers and reintroducing them to their natural habitat.

The Biblical Zoo in Jerusalem, Israel is part of an international matchmaking program designed to mate Sumatran tigers and save them from extinction.

In August of 2009, thieves broke into the Taman Rimba Zoo on Sumatra and poached a
female Sumatran Tiger.

Bali Tiger

The Bali Tiger (Panthera tigris balica), harimau Bali in Indonesian, or referred to as samong in archaic Balinese language, is an extinct subspecies of tiger which was found solely on the small Indonesian island of Bali. This was one of three sub-species of tiger found in Indonesia along with the Javan tiger (also possibly extinct) and Sumatran tiger (critically endangered).

It was the smallest of the tiger sub-species; the sub-species was declared extinct on September 27, 1937 after a tigress was shot at Sumbar Kima, west Bali. Given the small size of the island, and limited forest cover, the original population could never have been large, and it is considered unlikely that any survive today.

The sub-species became extinct because of habitat loss and hunting.

Characteristics

Size

The Bali Tiger was the smallest of all eight tiger subspecies, rather comparable with the African leopard or North American cougar (otherwise known as the mountain lion) in size. The weight of a male tiger was usually 90-100 kg (198-221 pounds); that of a female was 65-80 kg (142-175 pounds). The male was 220 cm (7.2 feet or 86.6 inches) in length (together with tail), the female 195-200 cm.
Appearance

Bali Tigers had short fur that was deep orange colored and darker, fewer stripes than other tiger sub-species. Occasionally, between the stripes, there were small black spots. Bali tigers also had unusual bar-shaped patterns on the head.

Diet

Like all tigers, Bali tigers were carnivorous. They preyed upon most mammals that lived within their habitat. Their major sources of food were wild boars, rusa deer, kijang, red junglefowls, monitor lizards, monkeys and possibly wild banteng (now also extirpated on the island). The only known predators of Bali tigers were humans.

Reproduction

Female Bali Tigers, after mating, had a gestation period of 103 days on average. They begat two or three cubs per litter, and the cubs weighed two or three pounds at birth. They were born blind. Cubs were weaned at around one year of age, and were fully independent at 18 months to two years of age. Bali Tigers lived up to approximately 8-10 years of age.

Relationship to the Javanese tiger

There are two common theories regarding the divergence of Balinese and Javan tigers. The first idea suggests that the two subspecies developed when Bali became isolated from Java by formation of the Bali Strait by rising sea levels after the ice age. This split the tigers into two groups which then went on to develop independently.

The second possibility is that the tiger swam from one island to colonize the other. The Bali Strait is only 2.4 kilometers wide, making it well within the swimming ability of the average tiger. Whichever it was, the two went on to become quite different.

Documentation, hunting and tiger culture in Bali

The hunting party of Baron Oskar Vojnich with a Balinese tiger, shot at Gunung Gondol, NW Bali, Nov. 1911

In Balinese culture, the tiger had a special place in folk tales and traditional arts, like in the Kamasan paintings of Klungkung kingdom. However, they were perceived as a destructive force and culling efforts were encouraged all the way to the time of extinction.

Very few reliable accounts of encounters and even fewer visual documentations remain. One of the most complete records was left by the Hungarian baron Oszkár Vojnich, who trapped, hunted and took photos of a Balinese tiger. On November 3, 1911 he shot dead an adult specimen in the northwest region, between Gunung Gondol and Banyupoh River, documenting it in his book "In The East Indian Archipelago" (Budapest 1913).

According to the same book, the preferred method of hunting tigers in the island was catching them with a concealed, large and heavy steel foot trap over bait (goat or muntjak) and then dispatching it with a firearm at close quarters.

As in this example, a final blow to the ever low numbers of island's tiger population was during the Dutch colonial period, when shikari hunting trips were conducted by European sportsmen coming from Java, armed with high powered rifles and a romantic but disastrous Victorian hunting mentality. Surabayan gunmaker E. Munaut is confirmed with killing over twenty tigers in Bali, over span of a few years.
A Balinese tiger shot in 1925, hunting party unknown, likely European hunters with Javanese trackers

The last confirmed tiger was an adult female, killed on Sep. 27, 1937 at Sumbar Kima, western Bali; since then, claims of sighting have been made, but without proof, mostly by forestry officers, in 1952, 1970 and 1972. The last remaining tigers were pushed into the western side of the island, mostly into area that is now Bali Barat National Park, established in 1947.

The Balinese tiger was never captured alive on film, on motion picture or displayed in a public zoo, but a few skulls, skins and bones are preserved in museums. The British Museum in London has the largest collection with two skins and three skulls; others include Senckenberg Museum in Frankfurt, Naturkunde Museum in Stuttgart, Naturalis museum in Leiden and Zoological Museum of Bogor, Indonesia, which owns the remnants of the last known Balinese tiger. In 1997 a skull emerged from the old collection of Hungarian Natural History Museum and was scientifically studied and properly documented.

Unlike stag hunting, which they mastered, very few if any Balinese launched into stalking tigers, which aside from posing danger, was shone upon by malefic superstitions. Still, tigers had a well defined position in folkloric beliefs and magic. For example, the Balinese considered ground powdered tiger whiskers to be a potent and undetectable poison for one's foe. According to the same book mentioning this, Miguel Covarrubias's "Island Of The Gods", 1937, when a Balinese baby was born he was given a protective amulet necklace with black coral and "a tiger's tooth or a piece of tiger bone".

Many Balinese people are fond of wearing tiger parts jewelry, like in other Asian nations, for status or spiritual reasons like power and protection. Necklaces of teeth and claws or male rings cabochoned with polished tiger tooth ivory still exist in everyday use. As the tiger population disappeared on both Bali and neighboring Java, old parts have been recycled, or leopard and sun bear body parts have been used instead. One of the traditional Balinese dances, the Barong, still preserves in one of its four forms a type called the Tiger Barong (Barong Macan).

source: www.wikipedia.com

Bali Starling

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 with 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 similar.

Naming

Placed in the monotypic genus Leucopsar, it appears to be most closely related to Sturnia and the Brahminy Starling which is currently placed in Sturnus but will probably soon be split therefrom as Sturnus as presently delimited is highly paraphyletic (Jønsson & Fjeldså 2006). The specific name commemorates the British ornithologist Lord Rothschild, who described the bird in 1912.

Distribution

The Bali Starling is distributed and endemic to the island of Bali in Indonesia, where it is the island's only surviving endemic vertebrate species. This rare bird was discovered in 1910. Bali's other 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 jalak bali .

Behaviour

In its natural habitat however it is far less conspicuous, using tree tops for cover and - unlike other starlings - usually coming only to the ground to drink; this would seem to be an adaptation to the fact that it is instantly noticeable to predators when out in the open.

Endangered

The Bali Starling is critically endangered, hovering immediately above extinction in the wild for several 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, the Bali Starling is so much in danger that that national park has been set up just for the 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 towards extinction has been caused by the urbanization of the island and by 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 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.

The Bali Starling Conservation Project was Begawan Foundation's first initiative, commencing when the Foundation purchased two pairs of birds from the aviaries of Mr Nick Wileman, a successful and knowledgeable breeder living near London, and brought them “home” to Bali on 24th June 1999.
The Foundation developed a successful breeding programme with excellent facilities and expert supervision by Bali’s leading avian veterinarian, Drh I. G. N. Bayu Wirayudha. By November 2005, the Foundation’s captive population had grown from four birds, returned to Bali from UK, to 97 birds. In July 2006, the first 25 micro-chipped birds were released into the wild on Nusa Penida, a small island south of mainland Bali. Further releases followed and, by end of August 2009, a total of 65 birds had been released and 62 of their offspring were known to have survived and were flying free.

In 2005, most of the birds, along with their cages, were moved from Begawan Giri Estate to a newly established bird sanctuary, on Nusa Penida, a small island south of mainland Bali. 



Drh I. G. N. Bayu Wirayudha had already begun to prepare for the arrival of the birds and the release of the first batch of them on Nusa Penida a year earlier. One of his most important tasks was to educate local villagers about the importance of their survival. In April 2006, as a result of being approached by FNPF over a period of two years, the Nusa Penida traditional council, which represents 35 villages, unanimously agreed to protect all the birds on the island by passing a local traditional law (Hukum Adat) to protect them. Anyone caught harming them would face both fines and ostracism by the community. This allowed Nusa Penida to be gazetted as a Bird Sanctuary, now operated by FNPF.

Meanwhile, the birds being prepared for release demonstrated excellent flying skills. Unpeeled and uncut fruit was placed in different areas of their socialisation cage daily. They were also able to supplement their diet by catching insects that were attracted into the cage by a small light. 

Sprinklers placed on top of the cage dripped water onto leaves inside, and the birds became accustomed to drinking it in order to maximise their water intake at certain times when they were not given any water. They also learned how to get moisture from watery foods and trees, such as the banana palm, and how to find water in holes in trees and from items such as old shells on the ground. To help them identify potential predators, the birds were threatened with large artificial birds, fake snakes, and human beings who were not their keepers.



Finally, on July 10th, 2006, 25 micro-chipped birds were released into the wild during a ceremony that involved local villagers, temples and provincial and local government officials. Microchips were supplied by Theo Pagel, Director of the Cologne Zoo in Germany.

Within two weeks of their release, several birds had paired up and were observed bringing nesting materials to a variety of local trees, ficus, sugar palms and coconuts. Their first eggs had hatched by September 10th, and on September 28th, three birds instead of two were observed on the nesting tree. The first Bali Starlings to be released into the wild had started a family!

Twelve more birds were released on December 12th, 2006, and this flock was soon joined by two young birds that were the offspring of birds from the first release. 

On April 28th, 2007, President Susilo Bambang Yudhoyono of the Republic of Indonesia and First Lady Kristiani Herawati released a further 12 birds when they visited Nusa Penida to celebrate the launch of a ferry service to mainland Bali.

Further official recognition of the Programme came during a visit to Nusa Penida on August 25th by the Indonesian Forestry Minister M. S. Kaban and Dr Ir Tonny Suhartono, the Director General for Forestry Preservation and Nature Conservation. These two dignitaries officially announced that the island was a suitable site for further releases of Bali Starlings.

The birds, originally released in just three sites, have spread far and wide around the island. As of August 2009, a total of 65 birds have been released from the captive breeding cages. With thirteen chicks being hatched so far in the wild in 2009, the total number of Bali Starling chicks hatched and fledged by the end of August, since the inception of the release programme in 2006, is 62.

The Foundation continues to monitor and observe the birds in the wild, tracking where the birds nest and breed, ensuring that each bird released or born is followed throughout its life. This important role ensures that any future releases will be made with planned knowledge of how the bird survives in the wild, what food is required, and how it breeds.

source: wikipedia.com

Orangutan


The orangutans are two endangered species of great apes. Known for their intelligence, they live in trees and are the largest living arboreal animal. They have longer arms than other great apes, and their hair is typically reddish-brown, instead of the brown or black hair typical of other great apes. 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, the Thai-Malay Peninsula, Vietnam and China. There are only two surviving species in the genus Pongo: the Bornean Pongo pygmaeus and the critically endangered Sumatran Pongo abelii. The subfamily Ponginae includes the extinct genera Gigantopithecus and Sivapithecus.

An orangutan's standing height averages from 4 to 5 ft (1.2 to 1.5 m) and weighs between 73 to 180 pounds (33 to 82 kg). Males can weigh up to 250 lb (110 kg) or more. Orangutan hands are similar to humans hands; they have four long fingers and an opposable thumb. Their feet have four long toes and an opposable big toe. Orangutans can grasp things with both their hands and their feet. The largest males have an arm span of about 7.5 ft (2 m).

Orangutans have a large, bulky body, a thick neck, very long, strong arms, short, bowed legs, and no tail. They are mostly covered with long reddish-brown hair, although this differs between the species: Sumatran Orangutans have a more sparse and lighter coloured coat.

The orangutan has a large head with a prominent mouth area. Adult males have large cheek flaps (which get larger as the ape ages) that show their dominance to other males and their readiness to mate to other females. The age of maturity for females is approximately 12 years. Orangutans may live for about 50 years in the wild. However, thousands of orangutans don't reach adulthood due to human disruption. Orangutans are killed for food while others are killed because of disruption in people's property. Mother orangutans are killed so their infants can be sold as pets. Many of the infants die without the help of their mother.

Orangutans are the most arboreal of the great apes, spending nearly all of their time in the trees. Every night they fashion sleeping nests from branches and foliage. They are more solitary than other apes; males and females generally come together only to mate. Mothers stay with their babies for six or seven years. There is significant sexual dimorphism: females can grow to around 4 ft (1 m) 2 in or 127 cm and weigh around 100 lb (45 kg) while flanged adult males can reach 5 ft 9 in or 175 cm in height and weigh over 260 lb (118 kg).

The arms of orangutans 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 than 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 are instead fist-walkers.

Diet

Fruit makes up 65–90 percent of the orangutan diet. Fruits with sugary or fatty pulp are favored. Ficus fruits are commonly eaten, because they are easy to harvest and digest. Lowland Dipterocarp forests are preferred by orangutans because of their plentiful fruit; the same forests provide excellent timber for the logging industry and good soil conditions for palm oil plantations. Bornean orangutans consume at least 317 different food items that include: young leaves, shoots, bark, insects, honey and bird eggs.

Orangutans are opportunistic foragers, and their diets vary markedly from month to month. Bark is consumed as a last resort in times of food scarcity; fruits are always preferred.

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.

Geophagy, the practice of eating soil or rock, has been observed in orangutans. There are three main reasons for this dietary behavior; for the addition of minerals nutrients to their diet; for the ingestion of clay minerals that can absorb toxic substances; or to treat a disorder such as diarrhea.

Orangutans use plants of the genus Commelina as an anti-inflammatory balm.

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 research 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-week old orangutan

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.
Orangutan "laughing"

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.

A 2008 study of two orangutans at the Leipzig Zoo showed that orangutans are the first non-human species documented to use 'calculated reciprocity' which involves weighing the costs and benefits of gift exchanges and keeping track of these over time.

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 do not swim. At least one population at a conservation refuge on Kaja island in Borneo have been photographed wading in deep water.

Orangutans, along with Chimpanzees, gorillas, and other apes, 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 (Pongo abelii)

Pongo pygmaeus

The populations on the two 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. The population currently listed as P. p. wurmbii may be closer to the Sumatran Orangutan than the Bornean Orangutan. If confirmed, abelii would be a subspecies of P. wurmbii (Tiedeman, 1808). Regardless, the type locality of pygmaeus has not been established beyond doubts, and may be from the population currently listed as wurmbii (in which case wurmbii would be a junior synonym of pygmaeus, while one of the names currently considered a junior synonym of pygmaeus would take precedence for the northwest Bornean taxon). To further confuse, the name morio, as well as various junior synonyms that have been suggested, have been considered likely to all be junior synonyms of the population listed as pygmaeus in the above, thus leaving the east Bornean populations unnamed.

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 percent 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). The largest remaining population is found in the forest around the Sabangau River, but this environment is at risk. A similar development have been observed for the Sumatran orangutans.
Sumatran Orangutan at the orangutan rehabilitation center in Bukit Lawang

The most recent estimate for the Sumatran Orangutan is around 7,300 individuals in the wild 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.
Video of Orangutans at a rehabilitation centre in Borneo
Play video

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 and Sebangau 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.

source: www.wikipedia.com

Javan Rhinoceros



The Javan Rhinoceros (Sunda Rhinoceros to be more precise) or Lesser One-horned Rhinoceros (Rhinoceros sondaicus) is a member of the family Rhinocerotidae and one of five extant rhinoceroses. It belongs to the same genus as the Indian Rhinoceros, and has similar mosaicked skin which resembles armor, but at 3.1–3.2 m (10–10.5 feet) in length and 1.4–1.7 m (4.6–5.8 ft) in height, it is smaller than the Indian Rhinoceros, and is closer in size to the Black Rhinoceros. Its horn is usually less than 25 cm (10 inches), smaller than those of the other rhino species.

Once the most widespread of Asian rhinoceroses, the Javan Rhinoceros ranged from the islands of Indonesia, throughout Southeast Asia, and into India and China. The species is now critically endangered, with only two known populations in the wild, and none in zoos. It is possibly the rarest large mammal on earth. A population of at least 40–50 live in Ujung Kulon National Park on the island of Java in Indonesia and a small population, estimated in 2007 to be no more than eight, survives in Cat Tien National Park in Vietnam. The decline of the Javan Rhinoceros is attributed to poaching, primarily for their horns, which are highly valued in traditional Chinese medicine, fetching as much as $30,000 per kilogram on the black market. Loss of habitat, especially as the result of wars, such as the Vietnam War, in Southeast Asia, has also contributed to the species's decline and hindered recovery. The remaining range is only within two nationally protected areas, but the rhinos are still at risk from poachers, disease and loss of genetic diversity leading to inbreeding depression.

The Javan Rhino can live approximately 30–45 years in the wild. It historically inhabited lowland rain forest, wet grasslands and large floodplains. The Javan Rhino is mostly solitary, except for courtship and child-rearing, though groups may occasionally congregate near wallows and salt licks. Aside from humans, adults have no predators in their range. The Javan Rhino usually avoids humans, but will attack when it feels threatened. Scientists and conservationists rarely study the animals directly due to their extreme rarity and the danger of interfering with such an endangered species. Researchers rely on camera traps and fecal samples to gauge health and behavior. Consequently, the Javan Rhino is the least studied of all rhino species.

Taxonomy and naming

The first studies of the Javan Rhinoceros by naturalists from outside of its region took place in 1787 when two animals were shot in Java. The skulls were sent to the renowned Dutch naturalist Petrus Camper, who died in 1789 before he was able to publish his discovery that the rhinos of Java were a distinct species. Another Javan Rhinoceros was shot on the island of Sumatra by Alfred Duvaucel who sent the specimen to his stepfather Georges Cuvier, a famous French scientist. Cuvier recognized the animal as a distinct species in 1822, and in the same year it was identified by Anselme Gaëtan Desmarest as Rhinoceros sondaicus. It was the last species of rhinoceros to be identified. Desmarest initially identified the rhino as being from Sumatra, but later amended this to say his specimen was from Java.

The genus name Rhinoceros, which also includes the Indian Rhinoceros, is derived from Greek: rhino meaning nose, and ceros meaning horn; sondaicus is derived from sunda, the biogeographical region that comprises islands of Sumatra, Java, Borneo, and surrounding smaller islands. The Javan Rhino is also known as the Lesser One-Horned Rhinoceros (in contrast with the Greater One-Horned Rhinoceros, another name for the Indian Rhino).

There are three distinct subspecies, of which only two are presumed to be extant:

* Rhinoceros sondaicus sondaicus, the type subspecies, known as the Indonesian Javan Rhinoceros, once lived on Java and Sumatra. The population is now confined to around 40–50 animals in the Ujung Kulon National Park on the western tip of the island of Java. One researcher has suggested that the Javan Rhino on Sumatra belonged to a distinct subspecies, R.s. floweri, but this is not widely accepted.

* Rhinoceros sondaicus annamiticus, known as the Vietnamese Javan Rhinoceros or Vietnamese Rhinoceros, once lived across Vietnam, Cambodia, Laos and into Thailand and Malaysia. Annamiticus is derived from the Annamite Mountain Range in Southeast Asia, part of this subspecies's range. A single population, estimated at less than 12 remaining rhinos, lives in an area of lowland forest in the Cat Tien National Park in Vietnam. Genetic analysis suggests that the two extant subspecies last shared a common ancestor between 300,000 and 2 million years ago.

* Rhinoceros sondaicus inermis, known as the Indian Javan Rhinoceros, once ranged from Bengal to Burma, but is presumed to have gone extinct in the first decade of the 1900s. Inermis means unarmed, as the most distinctive characteristic of this sub-species is the small horns in males, and evident lack of horns in females. The original specimen of this species was a hornless female. The political situation in Burma has prevented assessment of the species in that country, but its survival is considered unlikely.

Evolution

Ancestral rhinoceroses first diverged from other Perissodactyls in the Early Eocene. Mitochondrial DNA comparison suggests that the ancestors of modern rhinos split from the ancestors of Equidae around 50 million years ago. The extant family, the Rhinocerotidae, first appeared in the Late Eocene in Eurasia, and the ancestors of the extant rhino species dispersed from Asia beginning in the Miocene.

The Indian and Javan Rhinoceros, the only members of the genus Rhinoceros, first appear in the fossil record in Asia around 1.6 million–3.3 million years ago. Molecular estimates, however, suggest the species may have diverged much earlier, around 11.7 million years ago. Although belonging to the type genus, the Indian and Javan Rhinoceros are not believed to be closely related to other rhino species. Different studies have hypothesized that they may be closely related to the extinct Gaindetherium or Punjabitherium. A detailed cladistic analysis of the Rhinocerotidae placed Rhinoceros and the extinct Punjabitherium in a clade with Dicerorhinus, the Sumatran Rhino. Other studies have suggested the Sumatran Rhinoceros is more closely related to the two African species. The Sumatran Rhino may have diverged from the other Asian rhinos as far back as 15 million years ago.

Description

The Javan Rhino is smaller than its cousin, the Indian Rhinoceros, and is close in size to the Black Rhinoceros. The body length of the Javan Rhino (including its head) can be up to 3.1–3.2 m (10–10.5 feet), and it can reach a height of 1.4–1.7 m (4.6–5.8 ft). Adults are variously reported to weigh between 900 and 2,300 kg (2,000 and 5,100 lb), although because they are endangered, a study to collect accurate measurements of the animals has never been conducted and is not a priority. There is not a substantial size difference between genders, but females may be slightly bigger. The rhinos in Vietnam appear to be significantly smaller than those in Java, based on studies of photographic evidence and measurements of their footprints.

Like its Indian cousin, the Javan Rhinoceros has a single horn (the other extant species have two horns). Its horn is the smallest of all extant rhinos, usually less than 20 cm (7.9 inches) with the longest recorded only 27 cm (10½ in). The Javan Rhinoceros does not appear to often use its horn for fighting, but instead uses it to scrape mud away in wallows, to pull down plants for eating, and to open paths through thick vegetation. Similar to the other browsing species of rhino (the Black, Sumatran and Indian Rhinoceroses), the Javan Rhino has long, pointed, upper lips which help in grabbing food. Its lower incisors are long and sharp; when the Javan Rhino fights it uses these teeth. Behind the incisors, two rows of six low-crowned molars are used for chewing coarse plants. Like all rhinos, the Javan Rhino smells and hears well but has very poor vision. They are estimated to live for 30 to 45 years.

Its hairless, splotchy gray or gray-brown skin falls in folds to the shoulder, back and rump. The skin has a natural mosaic pattern which lends the rhino an armored appearance. The neck folds of the Javan Rhinoceros are smaller than those of the Indian Rhinoceros, but still form a saddle shape over the shoulder. Because of the risks of interfering with such an endangered species, however, the Javan Rhinoceros is primarily studied through fecal sampling and camera traps. They are rarely encountered, observed or measured directly.

Distribution and habitat

Even the most optimistic estimate suggests there are fewer than 100 Javan Rhinos in the wild. They are considered possibly the most endangered of all large mammals; although there are more Sumatran Rhinos, their range is not as protected as that of the Javan Rhinos, and some conservationists consider them to be at greater risk. The Javan Rhinoceros is only known to survive in two places, the Ujung Kulon National Park on the western tip of Java and the Cat Tien National Park about 150 km (90 miles) north of Ho Chi Minh City.

The animal was once widespread from Assam and Bengal (where their range would have overlapped with both the Sumatran and Indian Rhino) eastward to Myanmar, Thailand, Cambodia, Laos, Vietnam, and southwards to the Malay Peninsula and the islands of Sumatra, Java and possibly Borneo. The Javan Rhino primarily inhabits dense lowland rain forests, tall grass and reed beds that are plentiful with rivers, large floodplains, or wet areas with many mud wallows. Although it historically preferred low-lying areas, the subspecies in Vietnam has been pushed onto much higher ground (up to 2,000 m or 6,561 ft), probably because of human encroachment and poaching.

The range of the Javan Rhinoceros has been shrinking for at least 3,000 years. Starting around 1000 BC, the northern range of the rhinoceros extended into China, but began moving southward at roughly 0.5 km (0.3 mile) per year, as human settlements increased in the region. It likely became locally extinct in India in the first decade of the 20th century. The Javan Rhino was hunted to extinction on the Malaysian peninsula by 1932. By the end of the Vietnam War, the Vietnamese Rhinoceros was believed extinct across all of mainland Asia. Local hunters and woodcutters in Cambodia claim to have seen Javan Rhinos in the Cardamom Mountains, but surveys of the area have failed to find any evidence of them. A population may have existed on the island of Borneo as well, though these specimens could have been the Sumatran Rhinoceros, a small population of which still lives there.

Behavior

The Javan Rhinoceros is a solitary animal with the exception of breeding pairs and mothers with calves. They will sometimes congregate in small groups at salt licks and mud wallows. Wallowing in mud is a common behavior for all rhinos; the activity allows them to maintain a cool body temperature and helps prevent disease and parasite infestation. The Javan Rhinoceros does not generally dig its own mud wallows, preferring to use other animals' wallows or naturally occurring pits, which it will use its horns to enlarge. Salt licks are also very important because of the essential nutrients the rhino receives from the salt. Males's home ranges are larger at 12–20 km² (5–8 miles²) compared to the females's which are around 3–14 km² (1–5 mi²). Males's territories overlap each other less than those of females. It is not known if there are territorial fights

Males mark their territory with dung piles and by urine spraying. Scrapes made by the feet in the ground and twisted saplings also seem to be used for communication. Members of other rhino species have a peculiar habit of defecating in massive rhino dung piles and then scraping their back feet in the dung. The Sumatran and Javan Rhinoceros, while defecating in piles, do not engage in the scraping. This adaptation in behavior is thought to be ecological; in the wet forests of Java and Sumatra, the method may not be useful for spreading odors.

The Javan Rhino is much less vocal than the Sumatran; very few Javan Rhino vocalizations have ever been recorded. Adult Javan Rhinos have no known predators other than humans. The species, particularly in Vietnam, is skittish and retreats into dense forests whenever humans are near. Though a valuable trait from a survival standpoint, it has made the rhinos difficult to study. Nevertheless, when humans approach too closely, the Javan Rhino becomes aggressive and will attack, stabbing with the incisors of its lower jaw while thrusting upward with its head. Its comparatively anti-social behavior may be a recent adaptation to population stresses; historical evidence suggests that, like other rhinos, the species was once more gregarious.

Diet

The Javan Rhinoceros is herbivorous and eats diverse plant species, especially their shoots, twigs, young foliage and fallen fruit. Most of the plants favored by the species grow in sunny areas: in forest clearings, shrubland and other vegetation types with no large trees. The rhino knocks down saplings to reach its food and grabs it with its prehensile upper lip. It is the most adaptable feeder of all the rhino species. Currently it is a pure browser but probably once both browsed and grazed in its historical range. The rhino eats an estimated 50 kg (110 lb) of food daily. Like the Sumatran Rhino, it needs salt in its diet. The salt licks common in its historical range do not exist in Ujung Kulon, but the rhinos there have been observed drinking seawater, likely for the same nutritional need.

Reproduction

The sexual habits of the Javan Rhinoceros are difficult to study as the species is rarely observed directly and no zoos have specimens. Females reach sexual maturity at 3–4 years of age while the males are sexually mature at 6. Gestation is estimated to occur over a period around 16–19 months. The birth interval for this species is 4–5 years and the calf is weaned at around 2 years. The other four species of rhino all have similar mating behaviors and the presumption is that the Javan Rhino follows suit.

source: wikipedia.com

Komodo dragon

The Komodo dragon (Varanus komodoensis) is a venomous species of lizard that inhabits the islands of Komodo, Rinca, Flores, and Gili Motang in Indonesia. A member of the monitor lizard family (Varanidae), it is the largest living species of lizard, growing to an average length of 2 to 3 metres (6.6 to 9.8 ft) and weighing around 70 kilograms (150 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; their large size is also explained by the Komodo dragon's low metabolic rate. As a result of their size, these lizards dominate 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 among the rare vertebrates capable of parthenogenesis, in which females may lay viable eggs if males are absent.

Komodo dragons were first recorded by Western scientists in 1910. Their large size and fearsome reputation make 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.

Etymology

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).
Adult Komodo Dragon

Evolutionary history

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, extending their range as far east as the island of Timor. The Komodo dragon was believed to have differentiated from its Australian ancestors 4 million years ago. However, recent fossil evidence from Queensland suggests that the Komodo dragon evolved in Australia before spreading to Indonesia. Dramatic lowering of sea level during the last glacial period uncovered extensive stretches of continental shelf that the Komodo dragon colonized, becoming isolated in their present island range as sea levels rose afterwards.

Description
Closeup of a Komodo dragon's skin

In the wild, an adult Komodo dragon usually weighs around 70 kilograms (150 lb),although captive specimens often weigh more. The largest verified wild specimen was 3.13 metres (10.3 ft) long and weighed 166 kilograms (370 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 metres (980 ft), but because its retinas only contain cones, it is thought to have poor night vision. The Komodo dragon is able to see in colour, but has poor visual discrimination of stationary objects.
Komodo dragons video.wmv.OGG
Play video
A Komodo dragon on Komodo Island uses his tongue to sample the air.

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, a technique that has allowed the Komodo dragon to capture even the most lethal prey, such as the King Cobra. 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 help 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.
A young Komodo dragon photographed on Rinca feeding on a water buffalo carcass

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 they have been known to be killed and eaten by victors.
Komodo excrement is mostly white as the stomach is not capable of digesting the calcium found in the bones of the animals they eat.

The Komodo dragon's diet is wide-ranging, and includes invertebrates, other reptiles (including smaller Komodo dragons), birds, bird eggs, small mammals, monkeys, wild boar, goats, deer, horses, and water buffalo. Young Komodos will eat insects, eggs, geckos, and small mammals. Occasionally they consume humans and human corpses, digging up bodies from shallow graves. 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. When it comes to hunting the lizard is very picky, but will eat any type of carrion.

Venom

Auffenberg described the Komodo dragon as having septic pathogens in its saliva, specifically the bacteria: Escherichia coli, Staphylococcus sp., Providencia sp., Proteus morgani and P. mirabilis. He noted that while these pathogens can be found in the mouths of wild Komodo dragons, they disappear from the mouths of captive animals, due to a cleaner diet. This was verified by taking mucous samples from the external gum surface of the upper jaw of two freshly captured individuals. Saliva samples were analyzed by researchers at the University of Texas who found 57 different strains of bacteria growing in the mouths of three wild Komodo dragons including Pasteurella multocida. The rapid growth of this bacteria was noted by Friedking: "Normally it takes about three days for a sample of P. multocida to cover a petri dish; ours took eight hours. We were very taken aback by how virulent these strains were". This study supported the observation that wounds inflicted by the Komodo dragon are often associated with sepsis and subsequent infections in prey animals.

In late 2005, researchers at the University of Melbourne speculated that the perentie (Varanus giganteus), other species of monitor, and agamids may be somewhat venomous. The team believes that the immediate effects of bites from these lizards 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) all produced similar effects: rapid swelling, localized disruption of blood clotting, and shooting pain up to the elbow, with some symptoms lasting for several hours.

In 2009, the same researchers published further evidence demonstrating that Komodo dragons possess a venomous bite. MRI scans of a preserved skull showed the presence of two venom glands in the lower jaw. They extracted one of these glands from the head of a terminally ill specimen in the Singapore Zoological Gardens, and found that it secreted a venom containing several different toxic proteins. The known functions of these proteins include inhibition of blood clotting, lowering of blood pressure, muscle paralysis, and the induction of hypothermia, leading to shock and loss of consciousness in envenomated prey. As a result of the discovery, the previous theory that bacteria were responsible for the deaths of komodo victims was disputed.

Kurt Schwenk, an evolutionary biologist at the University of Connecticut finds the discovery of these glands intriguing, but considers most of the evidence for venom in the study to be "meaningless, irrelevant, incorrect or falsely misleading". Even if the lizards have venomlike proteins in their mouths, Schwenk argues, they may be using them for a different function, and he doubts that venom is necessary to explain the effect of a Komodo dragon bite, arguing that shock and blood loss are the primary factors.

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.
A Komodo dragon with its long tail and claws fully visible

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.


source: www.wikipedia.com