Post by rock on Apr 24, 2019 21:45:38 GMT 5
komodo dragon
The Komodo dragon[4] (Varanus komodoensis), also known as the Komodo monitor, is a species of lizard found in the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang.[5] A member of the monitor lizard family Varanidae, it is the largest living species of lizard, growing to a maximum length of 3 metres (10 ft) in rare cases and weighing up to approximately 70 kilograms (150 lb).[5]
Their unusually large size has been attributed to island gigantism, since no other carnivorous animals fill the niche on the islands where they live.[6][7] However, recent research suggests the large size of Komodo dragons may be better understood as representative of a relict population of very large varanid lizards that once lived across Indonesia and Australia, most of which, along with other megafauna, died out after the Pleistocene (as a result of human activity).[1] Fossils very similar to V. komodoensis have been found in Australia dating to greater than 3.8 million years ago, and its body size remained stable on Flores, one of the handful of Indonesian islands where it is currently found, over the last 900,000 years, "a time marked by major faunal turnovers, extinction of the island's megafauna, and the arrival of early hominids by 880 ka [kiloannums]."[1]
As a result of their size, these lizards dominate the ecosystems in which they live.[8] Komodo dragons hunt and ambush prey including invertebrates, birds, and mammals. It has been claimed that they have a venomous bite; there are two glands in the lower jaw which secrete several toxic proteins. The biological significance of these proteins is disputed, but the glands have been shown to secrete an anticoagulant. Komodo dragons' group behaviour in hunting is exceptional in the reptile world. The diet of big Komodo dragons mainly consists of Timor deer, though they also eat considerable amounts of carrion.[5] Komodo dragons also occasionally attack humans.[9]
Mating begins between May and August, and the eggs are laid in September. About 20 eggs are deposited in abandoned megapode nests or in a self-dug nesting hole.[5] The eggs are 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 8 to 9 years to mature, and are estimated to live up to 30 years.[5]
Komodo dragons were first recorded by Western scientists in 1910.[10] 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.[2] They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.In the wild, an adult Komodo dragon usually weighs around 70 kg (150 lb), although captive specimens often weigh more.[23] According to Guinness World Records, an average adult male will weigh 79 to 91 kg (174 to 201 lb) and measure 2.59 m (8.5 ft), while an average female will weigh 68 to 73 kg (150 to 161 lb) and measure 2.29 m (7.5 ft).[24] The largest verified wild specimen was 3.13 m (10.3 ft) long and weighed 166 kg (366 lb), including undigested food.[11]
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 cm (1 in) in length. Its saliva is frequently blood-tinged, because its teeth are almost completely covered by gingival tissue that is naturally lacerated during feeding.[25] It also has a long, yellow, deeply forked tongue.[11] Komodo dragon skin is reinforced by armoured scales, which contain tiny bones called osteoderms that function as a sort of natural chain-mail.[26][27] This rugged hide makes Komodo dragon skin a poor source of leather.Recent research has shown that Komodo dragons are like other monitor lizards in that they secrete venomous proteins in their mouths. Therefore, their saliva is venomous to some degree. However, Komodo dragon venom is unlike cobra venom, which can kill prey in just a few hours.
king cobra
The king cobra (Ophiophagus hannah), also known as the hamadryad, is a venomous snake species in the family Elapidae, endemic to forests from India through Southeast Asia. It is threatened by habitat destruction and has been listed as Vulnerable on the IUCN Red List since 2010.[1] It is the world's longest venomous snake.[2] Adult king cobras are 3.18 to 4 m (10.4 to 13.1 ft) long. The longest known individual measured 5.85 m (19.2 ft).[3] Despite the word "cobra" in its common name, this species does not belong to genus Naja but is the sole member of its own. It preys chiefly on other snakes and occasionally on some other vertebrates, such as lizards and rodents. It is a dangerous snake that has a fearsome reputation in its range,[4][5][6] although it typically avoids confrontation with humans when possible.[4] The king cobra is a prominent symbol in the mythology and folk traditions of India, Sri Lanka and Myanmar.[7][8] It is the national reptile of India.The king cobra was described and drawn by the Danish naturalist Theodore Edward Cantor in 1836, who gave it the scientific name Hamadryas hannah. Cantor had three specimens from the Sundarbans and one caught in the vicinity of Kolkata.[10] It was subordinated to the genus Ophiophagus by Albert Günther in 1864.[11]
Ophiophagus hannah belongs to the monotypic genus Ophiophagus in the family Elapidae, while most other cobras are members of the genus Naja. They can be distinguished from other cobras by size and hood. King cobras are generally larger than other cobras, and the stripe on the neck is a chevron instead of a double or single eye shape that may be seen in most of the other Asian cobras. Moreover, the hood of the king cobra is narrower and longer.[4] A key to identification, clearly visible on the head, is the presence of a pair of large scales known as occipitals, located at the back of the top of the head. These are behind the usual "nine-plate" arrangement typical of colubrids and elapids, and are unique to the king cobra.The skin of king cobra is dark olive or brown with black bands and white or yellow crossbands. The head is black with two crossbars near the snout and two behind the eyes. Adult king cobras are 3.18 to 4 m (10.4 to 13.1 ft) long. The longest known individual measured 5.85 m (19.2 ft).[3] Its belly is cream or pale yellow.[12] It has 17 to 19 rows of smooth scales. Ventral scales are uniformly oval shaped. Dorsal scales are placed in an oblique arrangement.[13] Males have 235 to 250 ventral scales, while females have 239 to 265. The subcaudal scales are single or paired in each row, numbering 83 to 96 in males and 77 to 98 in females.[citation needed]
Juveniles are shiny black with narrow yellow bands (can be mistaken for a banded krait, but readily identified with its expandable hood). The head of a mature snake can be quite massive and bulky in appearance, though like all snakes, it can expand its jaws to swallow large prey items. It has proteroglyph dentition, meaning it has two short, fixed fangs in the front of the mouth, which channel venom into the prey like hypodermic needles. The average lifespan of a wild king cobra is about 20 years.[12]
King cobras are sexually dimorphic in size, with males reaching larger sizes than females, which is an unusual trait among snakes whose females are usually larger than males. The length and mass of the snakes highly depend on their localities and some other factors.The king cobra typically weighs about 6 kg (13 lb). The longest known specimen was a captive one at the London Zoo, and grew to around 18.5 to 18.8 ft (5.6 to 5.7 m) before being euthanised upon the outbreak of World War II. The heaviest wild specimen was caught at Royal Island Club in Singapore in 1951, which weighed 12 kg (26 lb) and measured 4.8 m (16 ft), though an even heavier captive specimen was kept at New York Zoological Park and was measured as 12.7 kg (28 lb) at 4.4 m (14.4 ft) long in 1972.[citation needed] Some viper species, such as the eastern diamondback rattlesnake and the Gaboon viper, often much shorter in length but bulkier in build, rival the king cobra in average weight.They are comfortable in the trees, on land, and in water, feeding mainly on other snakes, venomous and nonvenomous. They will also eat fish , lizards, eggs, and rodents . They are the only snakes in the world that build nests for their eggs, which they guard ferociously until the hatchlings emerge.
The Komodo dragon[4] (Varanus komodoensis), also known as the Komodo monitor, is a species of lizard found in the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang.[5] A member of the monitor lizard family Varanidae, it is the largest living species of lizard, growing to a maximum length of 3 metres (10 ft) in rare cases and weighing up to approximately 70 kilograms (150 lb).[5]
Their unusually large size has been attributed to island gigantism, since no other carnivorous animals fill the niche on the islands where they live.[6][7] However, recent research suggests the large size of Komodo dragons may be better understood as representative of a relict population of very large varanid lizards that once lived across Indonesia and Australia, most of which, along with other megafauna, died out after the Pleistocene (as a result of human activity).[1] Fossils very similar to V. komodoensis have been found in Australia dating to greater than 3.8 million years ago, and its body size remained stable on Flores, one of the handful of Indonesian islands where it is currently found, over the last 900,000 years, "a time marked by major faunal turnovers, extinction of the island's megafauna, and the arrival of early hominids by 880 ka [kiloannums]."[1]
As a result of their size, these lizards dominate the ecosystems in which they live.[8] Komodo dragons hunt and ambush prey including invertebrates, birds, and mammals. It has been claimed that they have a venomous bite; there are two glands in the lower jaw which secrete several toxic proteins. The biological significance of these proteins is disputed, but the glands have been shown to secrete an anticoagulant. Komodo dragons' group behaviour in hunting is exceptional in the reptile world. The diet of big Komodo dragons mainly consists of Timor deer, though they also eat considerable amounts of carrion.[5] Komodo dragons also occasionally attack humans.[9]
Mating begins between May and August, and the eggs are laid in September. About 20 eggs are deposited in abandoned megapode nests or in a self-dug nesting hole.[5] The eggs are 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 8 to 9 years to mature, and are estimated to live up to 30 years.[5]
Komodo dragons were first recorded by Western scientists in 1910.[10] 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.[2] They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.In the wild, an adult Komodo dragon usually weighs around 70 kg (150 lb), although captive specimens often weigh more.[23] According to Guinness World Records, an average adult male will weigh 79 to 91 kg (174 to 201 lb) and measure 2.59 m (8.5 ft), while an average female will weigh 68 to 73 kg (150 to 161 lb) and measure 2.29 m (7.5 ft).[24] The largest verified wild specimen was 3.13 m (10.3 ft) long and weighed 166 kg (366 lb), including undigested food.[11]
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 cm (1 in) in length. Its saliva is frequently blood-tinged, because its teeth are almost completely covered by gingival tissue that is naturally lacerated during feeding.[25] It also has a long, yellow, deeply forked tongue.[11] Komodo dragon skin is reinforced by armoured scales, which contain tiny bones called osteoderms that function as a sort of natural chain-mail.[26][27] This rugged hide makes Komodo dragon skin a poor source of leather.Recent research has shown that Komodo dragons are like other monitor lizards in that they secrete venomous proteins in their mouths. Therefore, their saliva is venomous to some degree. However, Komodo dragon venom is unlike cobra venom, which can kill prey in just a few hours.
king cobra
The king cobra (Ophiophagus hannah), also known as the hamadryad, is a venomous snake species in the family Elapidae, endemic to forests from India through Southeast Asia. It is threatened by habitat destruction and has been listed as Vulnerable on the IUCN Red List since 2010.[1] It is the world's longest venomous snake.[2] Adult king cobras are 3.18 to 4 m (10.4 to 13.1 ft) long. The longest known individual measured 5.85 m (19.2 ft).[3] Despite the word "cobra" in its common name, this species does not belong to genus Naja but is the sole member of its own. It preys chiefly on other snakes and occasionally on some other vertebrates, such as lizards and rodents. It is a dangerous snake that has a fearsome reputation in its range,[4][5][6] although it typically avoids confrontation with humans when possible.[4] The king cobra is a prominent symbol in the mythology and folk traditions of India, Sri Lanka and Myanmar.[7][8] It is the national reptile of India.The king cobra was described and drawn by the Danish naturalist Theodore Edward Cantor in 1836, who gave it the scientific name Hamadryas hannah. Cantor had three specimens from the Sundarbans and one caught in the vicinity of Kolkata.[10] It was subordinated to the genus Ophiophagus by Albert Günther in 1864.[11]
Ophiophagus hannah belongs to the monotypic genus Ophiophagus in the family Elapidae, while most other cobras are members of the genus Naja. They can be distinguished from other cobras by size and hood. King cobras are generally larger than other cobras, and the stripe on the neck is a chevron instead of a double or single eye shape that may be seen in most of the other Asian cobras. Moreover, the hood of the king cobra is narrower and longer.[4] A key to identification, clearly visible on the head, is the presence of a pair of large scales known as occipitals, located at the back of the top of the head. These are behind the usual "nine-plate" arrangement typical of colubrids and elapids, and are unique to the king cobra.The skin of king cobra is dark olive or brown with black bands and white or yellow crossbands. The head is black with two crossbars near the snout and two behind the eyes. Adult king cobras are 3.18 to 4 m (10.4 to 13.1 ft) long. The longest known individual measured 5.85 m (19.2 ft).[3] Its belly is cream or pale yellow.[12] It has 17 to 19 rows of smooth scales. Ventral scales are uniformly oval shaped. Dorsal scales are placed in an oblique arrangement.[13] Males have 235 to 250 ventral scales, while females have 239 to 265. The subcaudal scales are single or paired in each row, numbering 83 to 96 in males and 77 to 98 in females.[citation needed]
Juveniles are shiny black with narrow yellow bands (can be mistaken for a banded krait, but readily identified with its expandable hood). The head of a mature snake can be quite massive and bulky in appearance, though like all snakes, it can expand its jaws to swallow large prey items. It has proteroglyph dentition, meaning it has two short, fixed fangs in the front of the mouth, which channel venom into the prey like hypodermic needles. The average lifespan of a wild king cobra is about 20 years.[12]
King cobras are sexually dimorphic in size, with males reaching larger sizes than females, which is an unusual trait among snakes whose females are usually larger than males. The length and mass of the snakes highly depend on their localities and some other factors.The king cobra typically weighs about 6 kg (13 lb). The longest known specimen was a captive one at the London Zoo, and grew to around 18.5 to 18.8 ft (5.6 to 5.7 m) before being euthanised upon the outbreak of World War II. The heaviest wild specimen was caught at Royal Island Club in Singapore in 1951, which weighed 12 kg (26 lb) and measured 4.8 m (16 ft), though an even heavier captive specimen was kept at New York Zoological Park and was measured as 12.7 kg (28 lb) at 4.4 m (14.4 ft) long in 1972.[citation needed] Some viper species, such as the eastern diamondback rattlesnake and the Gaboon viper, often much shorter in length but bulkier in build, rival the king cobra in average weight.They are comfortable in the trees, on land, and in water, feeding mainly on other snakes, venomous and nonvenomous. They will also eat fish , lizards, eggs, and rodents . They are the only snakes in the world that build nests for their eggs, which they guard ferociously until the hatchlings emerge.