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Giant panda
From Wikipedia, the free encyclopedia
This article is about the mammal in the bear family. For the red panda, see Red panda. For the hip hop group, see Giant Panda (group). For other uses, see Panda (disambiguation).
The giant panda, or panda (Ailuropoda melanoleuca, literally meaning "black and white cat-foot")[2] is a bear[3] native to central-western and south western China.[4] It is easily recognized by its large, distinctive black patches around the eyes, over the ears, and across its round body. Though it belongs to the order Carnivora, the panda's diet is 99% bamboo.[5] Pandas in the wild will occasionally eat other grasses, wild tubers, or even meat in the form of birds, rodents or carrion. In captivity they may receive honey, eggs, fish, yams, shrub leaves, oranges, or bananas along with specially prepared feed.[6][7]
The giant panda lives in a few mountain ranges in central China, mainly in Sichuan province, but also in the Shaanxi and Gansu provinces.[8] Due to farming, deforestation and other development, the panda has been driven out of the lowland areas where it once lived.
The panda is a conservation reliant endangered species.[4] A 2007 report shows 239 pandas living in captivity inside China and another 27 outside the country.[9] Wild population estimates vary; one estimate shows that there are about 1,590 individuals living in the wild,[9] while a 2006 study via DNA analysis estimated that this figure could be as high as 2,000 to 3,000.[10] Some reports also show that the number of pandas in the wild is on the rise.[11][12] However, the IUCN does not believe there is enough certainty yet to reclassify the species from Endangered to Vulnerable.[1]
While the dragon has historically served as China's national emblem, in recent decades the panda has also served as an emblem for the country. Its image appears on a large number of modern Chinese commemorative silver, gold, and platinum coins. Though the panda is often assumed to be docile, it has been known to attack humans, presumably out of irritation rather than predation
Description
The Giant Panda has a black-and-white coat. Adults measure around 1.5 meters (5 ft) long and around 75 centimeters (2 ft 6 in) tall at the shoulder. Males can weigh up to 150 kilograms (330 lb). Females (generally 10–20% smaller than males)[17] can weigh up to 125 kilograms (280 lb).
The Giant Panda has a black-and-white coat. Adults measure around 1.5 meters (5 ft) long and around 75 centimeters (2 ft 6 in) tall at the shoulder. Males can weigh up to 150 kilograms (330 lb). Females (generally 10–20% smaller than males)[17] can weigh up to 125 kilograms (280 lb).[4]
The Giant Panda has a body shape typical of bears. It has black fur on its ears, eye patches, muzzle, legs, arms and shoulders. The rest of the animal's coat is white. Although scientists do not know why these unusual bears are black and white, some speculate that the bold coloring provides effective camouflage in its shade-dappled snowy and rocky surroundings.[18] The Giant Panda's thick, wooly coat keeps it warm in the cool forests of its habitat.[18] The Giant Panda has large molar teeth and strong jaw muscles for crushing tough bamboo.[19]
The Giant Panda's paw has a "thumb" and five fingers; the "thumb" is actually a modified sesamoid bone, which helps the Giant Panda to hold bamboo while eating.[20] Stephen Jay Gould discusses this feature in his book of essays on evolution and biology, The Panda's Thumb.
The Giant Panda's tail, measuring 10 to 15 centimeters (4 to 6 in), is the second longest in the bear family. The longest belongs to the Sloth Bear.[17]
The Giant Panda usually lives around 20 years in the wild and up to 30 years in captivity.
Behavior
In the wild, the Giant Panda is a terrestrial animal and primarily spends its life roaming and feeding in the bamboo forests of the Qinling Mountains and in the hilly Sichuan Province.[22] Though generally alone, each adult has a defined territory and females are not tolerant of other females in their range. Pandas communicate through vocalization and scent marking such as clawing trees or spraying urine.[4] The Giant Panda is able to climb and take shelter in hollow trees or rock crevices but does not establish permanent dens. For this reason, pandas do not hibernate, which is similar to other subtropical mammals, and will instead move to elevations with warmer temperatures.[23] Pandas rely primarily on spatial memory rather than visual memory.[24]
Social encounters occur primarily during the brief breeding season in which pandas in proximity to one another will gather.[25] After mating, the male leaves the female alone to raise the cub.
Diet
Despite its taxonomic classification as a carnivoran, the Giant Panda's diet is primarily herbivorous, consisting almost exclusively of bamboo.[21] However, the Giant Panda still has the digestive system of a carnivore, as well as carnivore-specific genes,[27] and thus derives little energy and little protein from consumption of bamboo. Its ability to digest cellulose is ascribed to the microbes in its gut.[28] The average Giant Panda eats as much as 9 to 14 kg (20 to 30 pounds) of bamboo shoots a day. Because the Giant Panda consumes a diet low in nutrition, it is important for it to keep its digestive tract full.[21] The limited energy input imposed on it by its diet has affected the panda's behavior. The Giant Panda tends to limit its social interactions and avoids steeply sloping terrain in order to limit its energy expenditures.[29]
Two of the panda's most distinctive features, its large size and its round face, are adaptations to its bamboo diet. Panda researcher Russell Ciochon observed that: “[much] like the vegetarian gorilla, the low body surface area to body volume [of the giant panda] is indicative of a lower metabolic rate. This lower metabolic rate and a more sedentary lifestyle allow the giant panda to subsist on nutrient poor resources such as bamboo.”[29] Similarly, the Giant Panda's round face is the result of powerful jaw muscles, which attach from the top of the head to the jaw.[29] Large molars crush and grind fibrous plant material.
Pandas eat any of twenty-five bamboo species in the wild, such as Fargesia dracocephala[30] and Fargesia rufa.[31] Only a few bamboo species are widespread at the high altitudes pandas now inhabit. Bamboo leaves contain the highest protein levels; stems have less.[32] Given this large diet, the Giant Panda can defecate up to 40 times a day. [33]
Because of the synchronous flowering, death, and regeneration of all bamboo within a species, the Giant Panda must have at least two different species available in its range to avoid starvation. While primarily herbivorous, the Giant Panda still retains decidedly ursine teeth, and will eat meat, fish, and eggs when available. In captivity, zoos typically maintain the Giant Panda's bamboo diet, though some will provide specially-formulated biscuits or other dietary supplements.
Genomics
The giant panda genome was sequenced in 2009 using a next-generation sequencing technology.[35] Its genome contains 20 pairs of autosomes and one pair of sex chromosomes.
Classification
For many decades the precise taxonomic classification of the Giant Panda was under debate because it shares characteristics of both bears and raccoons.[36] However, molecular studies suggest that the Giant Panda is a true bear and part of the Ursidae family,[37][38] though it differentiated early in history from the main ursine stock. The Giant Panda's closest ursine relative is the Spectacled Bear of South America.[39] The Giant Panda has been referred to as a living fossil.[40]
Despite the shared name, habitat type, and diet, as well as a unique enlarged bone called the pseudo thumb (which helps them grip the bamboo shoots they eat), the Giant Panda and Red Panda are only distantly related. Molecular studies have placed the Red Panda in its own family Ailuridae, and not under Ursidae.
Subspecies
Two subspecies of Giant Panda have been recognized on the basis of distinct cranial measurements, color patterns, and population genetics (Wan et al., 2005).
* The nominate subspecies Ailuropoda melanoleuca melanoleuca consists of most extant populations of panda. These animals are principally found in Sichuan and display the typical stark black and white contrasting colors.
* The Qinling Panda, Ailuropoda melanoleuca qinlingensis[41] is restricted to the Qinling Mountains in Shaanxi at elevations of 1300–3000 m. The typical black and white pattern of Sichuan Giant Pandas is replaced with a dark brown versus light brown pattern. The skull of A. m. qinlingensis is smaller than its relatives, and it has larger molars.
Uses and human interaction
Early references
In the past, pandas were thought to be rare and noble creatures – the mother of Emperor Wen of Han was buried with a panda skull in her vault. The grandson of Emperor Taizong of Tang is said to have given Japan two pandas and a sheet of panda skin as a sign of goodwill. Unlike many other animals in Ancient China, pandas were rarely thought to have medical uses. The few known uses include the Sichuan tribal peoples' use of panda urine to melt accidentally swallowed needles, and the use of panda pelts to control menses as described in the Qin Dynasty encyclopedia Erya.[42]
The creature named mo (貘) mentioned in some ancient books has been interpreted as giant panda.[42] The dictionary Shuowen Jiezi (Eastern Han Dynasty) says that the mo, from Shu (Sichuan), is bear-like, but yellow-and-black,[43] although the older Erya describes mo simply as a "white leopard".[44] The interpretation of the legendary fierce creature pixiu (貔貅) as referring to the giant panda are also common.
The comparative obscurity of the giant panda throughout most of China's history is illustrated by the fact that, despite there being a number of depictions of bears in Chinese art starting from its most ancient times, and the bamboo being one of the favorite subjects for Chinese painters, there are no known pre-20th-century artistic representations of giant pandas.[46]
Modern "discovery"
The West first learned of the Giant Panda in 1869 because the French missionary Armand David [36] received a skin from a hunter on March 11, 1869. The first Westerner known to have seen a living Giant Panda is the German zoologist Hugo Weigold, who purchased a cub in 1916. Kermit and Theodore Roosevelt, Jr., became the first Westerners to shoot a panda, on an expedition funded by the Field Museum of Natural History in the 1920s. In 1936, Ruth Harkness became the first Westerner to bring back a live Giant Panda, a cub named Su Lin[47] who went to live at the Brookfield Zoo in Chicago. In 1938, five Giant Pandas were sent to London;[48][49] these activities were later halted because of wars and for the next half of the century, the West knew little of pandas.
Panda diplomacy
Main article: Panda diplomacy
Loans of Giant Pandas to American and Japanese zoos formed an important part of the diplomacy of the People's Republic of China in the 1970s, as it marked some of the first cultural exchanges between the People's Republic and the West. This practice has been termed "Panda diplomacy".
By 1984, however, pandas were no longer used as agents of diplomacy. Instead, China began to offer pandas to other nations only on 10-year loans. The standard loan terms include a fee of up to US$1,000,000 per year and a provision that any cubs born during the loan are the property of the People's Republic of China. Since 1998, due to a WWF lawsuit, the United States Fish and Wildlife Service only allows a U.S. zoo to import a panda if the zoo can ensure that China will channel more than half of its loan fee into conservation efforts for the Giant Panda and its habitat.
In May 2005, China offered a breeding pair to Taiwan. The issue became embroiled in cross-Strait relations—both over the underlying symbolism, and over technical issues such as whether the transfer would be considered "domestic" or "international," or whether any true conservation purpose would be served by the exchange.[50] China's offer was initially rejected by President Chen of Taiwan. However when the presidency changed hands China's offer was accepted at the beginning of Ma Ying-jeou's presidency in 2008, and the pandas themselves arrived in December of that year. A contest to name the pandas was held in China, resulting in the politically charged names "Tuan Tuan" and "Yuan Yuan" (from tuanyuan, meaning "reunion", i.e. "reunification").
Conservation
The Giant Panda is an endangered species, threatened by continued habitat loss and by a very low birthrate, both in the wild and in captivity.[21]
The Giant Panda has been a target for poaching by locals since ancient times and by foreigners since it was introduced to the West. Starting in the 1930s, foreigners were unable to poach Giant Pandas in China because of the Second Sino-Japanese War and the Chinese Civil War, but pandas remained a source of soft furs for the locals. The population boom in China after 1949 created stress on the pandas' habitat, and the subsequent famines led to the increased hunting of wildlife, including pandas. During the Cultural Revolution, all studies and conservation activities on the pandas were stopped. After the Chinese economic reform, demand for panda skins from Hong Kong and Japan led to illegal poaching for the black market, acts generally ignored by the local officials at the time.
Though the Wolong National Nature Reserve was set up by the PRC government in 1958 to save the declining panda population, few advances in the conservation of pandas were made, due to inexperience and insufficient knowledge of ecology. Many believed that the best way to save the pandas was to cage them. As a result, pandas were caged at any sign of decline, and suffered from terrible conditions. Because of pollution and destruction of their natural habitat, along with segregation due to caging, reproduction of wild pandas was severely limited. In the 1990s, however, several laws (including gun control and the removal of resident humans from the reserves) helped the chances of survival for pandas. With these renewed efforts and improved conservation methods, wild pandas have started to increase in numbers in some areas, even though they still are classified as a rare species.
In 2006, scientists reported that the number of pandas living in the wild may have been underestimated at about 1,000. Previous population surveys had used conventional methods to estimate the size of the wild panda population, but using a new method that analyzes DNA from panda droppings, scientists believe that the wild panda population may be as large as 3,000.[21] Although the species is still endangered, it is thought that the conservation efforts are working. As of 2006, there were 40 panda reserves in China, compared to just 13 reserves two decades ago.
The Giant Panda is among the world's most adored and protected rare animals, and is one of the few in the world whose natural inhabitant status was able to gain a UNESCO World Heritage Site designation. The Sichuan Giant Panda Sanctuaries, located in the southwest Sichuan province and covering seven natural reserves, were inscribed onto the World Heritage List in 2006.[52][53]
Not all conservationists agree that the money spent on conserving pandas is money well spent. Chris Packham has argued that breeding pandas in captivity is "pointless" because "there is not enough habitat left to sustain them".[54] Packham argues that the money spent on pandas would be better spent elsewhere,[54] and has said that he would "eat the last panda if I could have all the money we have spent on panda conservation put back on the table for me to do more sensible things with," though he has apologized for upsetting people who like pandas.[56] He points out that "The panda is possibly one of the grossest wastes of conservation money in the last half century."
Reproduction
Initially the primary method of breeding Giant Pandas in captivity was by artificial insemination, as they seemed to lose their interest in mating once they were captured.[57] This led some scientists to try extreme methods such as showing them videos of giant Pandas mating[58] and giving the males Viagra.[59] Only recently have researchers started having success with captive breeding programs, and they have now determined that Giant Pandas have comparable breeding to some populations of the American Black Bear, a thriving bear family. The current reproductive rate is considered one young every two years.[12][22]
Giant Pandas reach sexual maturity between the ages of four and eight, and may be reproductive until age 20.[60] The mating season is between March and May, when a female goes into her estrous cycle which lasts for two or three days and only occurs once a year.[61] When mating, the female is in a crouching, head-down position as the male mounts her from behind. Copulation time is short, ranging from thirty seconds to five minutes, but the male may mount her repeatedly to ensure successful fertilization. The gestation period ranges from 95 to 160 days.[61] Cubs weigh only 90 to 130 grams (3.2 to 4.6 ounces), which is about 1/800 of the mother's weight. [36]
If twins are born, usually only one survives in the wild. The mother will select the stronger of the cubs, and the weaker will die. It is thought that the mother cannot produce enough milk for two cubs since she does not store fat.[62] The father has no part in helping raise the cub.
When the cub is first born, it is pink, blind, and toothless. [63] A Giant Panda cub is also extremely small, and it is difficult for the mother to protect it because of the baby's size. It nurses from its mother's breast 6 to 14 times a day for up to 30 minutes at a time. For three to four hours, the mother may leave the den to feed, which leaves the cub defenseless. One to two weeks after birth, the cub's skin turns gray where its hair will eventually become black. A slight pink color may appear on cub's fur, as a result of a chemical reaction between the fur and its mother's saliva. A month after birth, the color pattern of the cub's fur is fully developed. A cub's fur is very soft and coarsens with age. The cub begins to crawl at 75 to 80 days; [36] mothers play with their cubs by rolling and wrestling with them. The cubs are able to eat small quantities of bamboo after six months,[64] though mother's milk remains the primary food source for most of the first year. Giant Panda cubs weigh 45 kg (100 pounds) at one year, and live with their mothers until they are 18 months to two years old. The interval between births in the wild is generally two years.
In July 2009, Chinese scientists confirmed the birth of the first cub to be successfully conceived through artificial insemination using frozen sperm.[65] The cub was born at 07:41 on 23 July that year in Sichuan as the third cub of You You, an 11-year-old.[65][66][67] The technique for freezing the sperm in liquid nitrogen was first developed in 1980 and the first birth was hailed as a solution to the problem of lessening Giant Panda semen availability which had led to in-breeding.[67][68] It has been suggested that panda semen, which can be frozen for decades, could be shared between different zoos to save the species.[65][66] It is expected that zoos in destinations such as San Diego in the United States and Mexico City will now be able to provide their own semen to inseminate more Giant Pandas.[68]
Attempts have also been made to reproduce giant pandas by interspecific pregnancy by implanting cloned panda embryos into the uterus of an animal of another species. This has resulted in panda fetuses, but no live births.
Name
There is no conclusive explanation of the origin of the word "panda". The closest candidate is the Nepali word ponya, possibly referring to the adapted wrist bone. The Western world originally applied this name to the Red Panda. Until 1901, when it was erroneously stated that it was related to the Red Panda, the Giant Panda was known as "mottled bear" (Ailuropus melanoleucus) or "particolored bear".[70]
In most encyclopedic sources, the name "panda" or "common panda" originally referred to the lesser-known Red Panda,[71] thus necessitating the inclusion of "giant" and "lesser/red" prefixes in front of the names. Even as of 2010[update] the Encyclopædia Britannica still used "giant panda" or "panda bear" for the bear [72] and simply "panda" for the Ailuridae,[73] despite the popular usage of the word "panda".
Since the earliest collection of Chinese writings, the Chinese language has given the bear 20 different names, such as 花熊 (hua xiong) "spotted bear" and 竹熊 (zhu xiong) "bamboo bear".[74] The most popular names in China today are 大熊貓 (dà xióng māo), literally "large bear cat", or just 熊貓 (xióng māo), "bear cat". The name may have been inspired by the Giant Panda's eyes, which have pupils that are cat-like vertical slits - unlike other bear species, which have round pupils.[75]
In Taiwan, the popular name for panda is the inverted 貓熊 (māo xióng) "cat bear," even though many encyclopedia and dictionaries in Taiwan still use "bear cat" as the correct name. Some linguists argue that, in this construction, "bear" instead of "cat" is the base noun, making this name more grammatically and logically correct, which may have led to the popular choice despite official writings.
In zoos
See also: Category:Famous giant pandas
Pandas have been kept in zoos as early as the Western Han Dynasty in China, where the writer Sima Xiangru notes that the panda was the most treasured animal in the emperor's garden of exotic animals in Xi'an. Not until the 1950s were pandas again recorded to have been exhibited in China's zoos.[76]
A 2006 New York Times article[77] outlined the economics of keeping pandas, which costs five times more than that of the next most expensive animal, an elephant. American zoos generally pay the Chinese government $1 million a year in fees, as part of a typical ten-year contract. San Diego's contract with China was to expire in 2008 but got a five-year extension at about half of the previous yearly cost. The last contract, with the Memphis Zoo in Memphis, Tennessee, ends in 2013.
Panda..........
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This article is about the mammal in the bear family. For the red panda, see Red panda. For the hip hop group, see Giant Panda (group). For other uses, see Panda (disambiguation).
The giant panda, or panda (Ailuropoda melanoleuca, literally meaning "black and white cat-foot")[2] is a bear[3] native to central-western and south western China.[4] It is easily recognized by its large, distinctive black patches around the eyes, over the ears, and across its round body. Though it belongs to the order Carnivora, the panda's diet is 99% bamboo.[5] Pandas in the wild will occasionally eat other grasses, wild tubers, or even meat in the form of birds, rodents or carrion. In captivity they may receive honey, eggs, fish, yams, shrub leaves, oranges, or bananas along with specially prepared feed.[6][7]
The giant panda lives in a few mountain ranges in central China, mainly in Sichuan province, but also in the Shaanxi and Gansu provinces.[8] Due to farming, deforestation and other development, the panda has been driven out of the lowland areas where it once lived.
The panda is a conservation reliant endangered species.[4] A 2007 report shows 239 pandas living in captivity inside China and another 27 outside the country.[9] Wild population estimates vary; one estimate shows that there are about 1,590 individuals living in the wild,[9] while a 2006 study via DNA analysis estimated that this figure could be as high as 2,000 to 3,000.[10] Some reports also show that the number of pandas in the wild is on the rise.[11][12] However, the IUCN does not believe there is enough certainty yet to reclassify the species from Endangered to Vulnerable.[1]
While the dragon has historically served as China's national emblem, in recent decades the panda has also served as an emblem for the country. Its image appears on a large number of modern Chinese commemorative silver, gold, and platinum coins. Though the panda is often assumed to be docile, it has been known to attack humans, presumably out of irritation rather than predation
Description
The Giant Panda has a black-and-white coat. Adults measure around 1.5 meters (5 ft) long and around 75 centimeters (2 ft 6 in) tall at the shoulder. Males can weigh up to 150 kilograms (330 lb). Females (generally 10–20% smaller than males)[17] can weigh up to 125 kilograms (280 lb).
The Giant Panda has a black-and-white coat. Adults measure around 1.5 meters (5 ft) long and around 75 centimeters (2 ft 6 in) tall at the shoulder. Males can weigh up to 150 kilograms (330 lb). Females (generally 10–20% smaller than males)[17] can weigh up to 125 kilograms (280 lb).[4]
The Giant Panda has a body shape typical of bears. It has black fur on its ears, eye patches, muzzle, legs, arms and shoulders. The rest of the animal's coat is white. Although scientists do not know why these unusual bears are black and white, some speculate that the bold coloring provides effective camouflage in its shade-dappled snowy and rocky surroundings.[18] The Giant Panda's thick, wooly coat keeps it warm in the cool forests of its habitat.[18] The Giant Panda has large molar teeth and strong jaw muscles for crushing tough bamboo.[19]
The Giant Panda's paw has a "thumb" and five fingers; the "thumb" is actually a modified sesamoid bone, which helps the Giant Panda to hold bamboo while eating.[20] Stephen Jay Gould discusses this feature in his book of essays on evolution and biology, The Panda's Thumb.
The Giant Panda's tail, measuring 10 to 15 centimeters (4 to 6 in), is the second longest in the bear family. The longest belongs to the Sloth Bear.[17]
The Giant Panda usually lives around 20 years in the wild and up to 30 years in captivity.
Behavior
In the wild, the Giant Panda is a terrestrial animal and primarily spends its life roaming and feeding in the bamboo forests of the Qinling Mountains and in the hilly Sichuan Province.[22] Though generally alone, each adult has a defined territory and females are not tolerant of other females in their range. Pandas communicate through vocalization and scent marking such as clawing trees or spraying urine.[4] The Giant Panda is able to climb and take shelter in hollow trees or rock crevices but does not establish permanent dens. For this reason, pandas do not hibernate, which is similar to other subtropical mammals, and will instead move to elevations with warmer temperatures.[23] Pandas rely primarily on spatial memory rather than visual memory.[24]
Social encounters occur primarily during the brief breeding season in which pandas in proximity to one another will gather.[25] After mating, the male leaves the female alone to raise the cub.
Diet
Despite its taxonomic classification as a carnivoran, the Giant Panda's diet is primarily herbivorous, consisting almost exclusively of bamboo.[21] However, the Giant Panda still has the digestive system of a carnivore, as well as carnivore-specific genes,[27] and thus derives little energy and little protein from consumption of bamboo. Its ability to digest cellulose is ascribed to the microbes in its gut.[28] The average Giant Panda eats as much as 9 to 14 kg (20 to 30 pounds) of bamboo shoots a day. Because the Giant Panda consumes a diet low in nutrition, it is important for it to keep its digestive tract full.[21] The limited energy input imposed on it by its diet has affected the panda's behavior. The Giant Panda tends to limit its social interactions and avoids steeply sloping terrain in order to limit its energy expenditures.[29]
Two of the panda's most distinctive features, its large size and its round face, are adaptations to its bamboo diet. Panda researcher Russell Ciochon observed that: “[much] like the vegetarian gorilla, the low body surface area to body volume [of the giant panda] is indicative of a lower metabolic rate. This lower metabolic rate and a more sedentary lifestyle allow the giant panda to subsist on nutrient poor resources such as bamboo.”[29] Similarly, the Giant Panda's round face is the result of powerful jaw muscles, which attach from the top of the head to the jaw.[29] Large molars crush and grind fibrous plant material.
Pandas eat any of twenty-five bamboo species in the wild, such as Fargesia dracocephala[30] and Fargesia rufa.[31] Only a few bamboo species are widespread at the high altitudes pandas now inhabit. Bamboo leaves contain the highest protein levels; stems have less.[32] Given this large diet, the Giant Panda can defecate up to 40 times a day. [33]
Because of the synchronous flowering, death, and regeneration of all bamboo within a species, the Giant Panda must have at least two different species available in its range to avoid starvation. While primarily herbivorous, the Giant Panda still retains decidedly ursine teeth, and will eat meat, fish, and eggs when available. In captivity, zoos typically maintain the Giant Panda's bamboo diet, though some will provide specially-formulated biscuits or other dietary supplements.
Genomics
The giant panda genome was sequenced in 2009 using a next-generation sequencing technology.[35] Its genome contains 20 pairs of autosomes and one pair of sex chromosomes.
Classification
For many decades the precise taxonomic classification of the Giant Panda was under debate because it shares characteristics of both bears and raccoons.[36] However, molecular studies suggest that the Giant Panda is a true bear and part of the Ursidae family,[37][38] though it differentiated early in history from the main ursine stock. The Giant Panda's closest ursine relative is the Spectacled Bear of South America.[39] The Giant Panda has been referred to as a living fossil.[40]
Despite the shared name, habitat type, and diet, as well as a unique enlarged bone called the pseudo thumb (which helps them grip the bamboo shoots they eat), the Giant Panda and Red Panda are only distantly related. Molecular studies have placed the Red Panda in its own family Ailuridae, and not under Ursidae.
Subspecies
Two subspecies of Giant Panda have been recognized on the basis of distinct cranial measurements, color patterns, and population genetics (Wan et al., 2005).
* The nominate subspecies Ailuropoda melanoleuca melanoleuca consists of most extant populations of panda. These animals are principally found in Sichuan and display the typical stark black and white contrasting colors.
* The Qinling Panda, Ailuropoda melanoleuca qinlingensis[41] is restricted to the Qinling Mountains in Shaanxi at elevations of 1300–3000 m. The typical black and white pattern of Sichuan Giant Pandas is replaced with a dark brown versus light brown pattern. The skull of A. m. qinlingensis is smaller than its relatives, and it has larger molars.
Uses and human interaction
Early references
In the past, pandas were thought to be rare and noble creatures – the mother of Emperor Wen of Han was buried with a panda skull in her vault. The grandson of Emperor Taizong of Tang is said to have given Japan two pandas and a sheet of panda skin as a sign of goodwill. Unlike many other animals in Ancient China, pandas were rarely thought to have medical uses. The few known uses include the Sichuan tribal peoples' use of panda urine to melt accidentally swallowed needles, and the use of panda pelts to control menses as described in the Qin Dynasty encyclopedia Erya.[42]
The creature named mo (貘) mentioned in some ancient books has been interpreted as giant panda.[42] The dictionary Shuowen Jiezi (Eastern Han Dynasty) says that the mo, from Shu (Sichuan), is bear-like, but yellow-and-black,[43] although the older Erya describes mo simply as a "white leopard".[44] The interpretation of the legendary fierce creature pixiu (貔貅) as referring to the giant panda are also common.
The comparative obscurity of the giant panda throughout most of China's history is illustrated by the fact that, despite there being a number of depictions of bears in Chinese art starting from its most ancient times, and the bamboo being one of the favorite subjects for Chinese painters, there are no known pre-20th-century artistic representations of giant pandas.[46]
Modern "discovery"
The West first learned of the Giant Panda in 1869 because the French missionary Armand David [36] received a skin from a hunter on March 11, 1869. The first Westerner known to have seen a living Giant Panda is the German zoologist Hugo Weigold, who purchased a cub in 1916. Kermit and Theodore Roosevelt, Jr., became the first Westerners to shoot a panda, on an expedition funded by the Field Museum of Natural History in the 1920s. In 1936, Ruth Harkness became the first Westerner to bring back a live Giant Panda, a cub named Su Lin[47] who went to live at the Brookfield Zoo in Chicago. In 1938, five Giant Pandas were sent to London;[48][49] these activities were later halted because of wars and for the next half of the century, the West knew little of pandas.
Panda diplomacy
Main article: Panda diplomacy
Loans of Giant Pandas to American and Japanese zoos formed an important part of the diplomacy of the People's Republic of China in the 1970s, as it marked some of the first cultural exchanges between the People's Republic and the West. This practice has been termed "Panda diplomacy".
By 1984, however, pandas were no longer used as agents of diplomacy. Instead, China began to offer pandas to other nations only on 10-year loans. The standard loan terms include a fee of up to US$1,000,000 per year and a provision that any cubs born during the loan are the property of the People's Republic of China. Since 1998, due to a WWF lawsuit, the United States Fish and Wildlife Service only allows a U.S. zoo to import a panda if the zoo can ensure that China will channel more than half of its loan fee into conservation efforts for the Giant Panda and its habitat.
In May 2005, China offered a breeding pair to Taiwan. The issue became embroiled in cross-Strait relations—both over the underlying symbolism, and over technical issues such as whether the transfer would be considered "domestic" or "international," or whether any true conservation purpose would be served by the exchange.[50] China's offer was initially rejected by President Chen of Taiwan. However when the presidency changed hands China's offer was accepted at the beginning of Ma Ying-jeou's presidency in 2008, and the pandas themselves arrived in December of that year. A contest to name the pandas was held in China, resulting in the politically charged names "Tuan Tuan" and "Yuan Yuan" (from tuanyuan, meaning "reunion", i.e. "reunification").
Conservation
The Giant Panda is an endangered species, threatened by continued habitat loss and by a very low birthrate, both in the wild and in captivity.[21]
The Giant Panda has been a target for poaching by locals since ancient times and by foreigners since it was introduced to the West. Starting in the 1930s, foreigners were unable to poach Giant Pandas in China because of the Second Sino-Japanese War and the Chinese Civil War, but pandas remained a source of soft furs for the locals. The population boom in China after 1949 created stress on the pandas' habitat, and the subsequent famines led to the increased hunting of wildlife, including pandas. During the Cultural Revolution, all studies and conservation activities on the pandas were stopped. After the Chinese economic reform, demand for panda skins from Hong Kong and Japan led to illegal poaching for the black market, acts generally ignored by the local officials at the time.
Though the Wolong National Nature Reserve was set up by the PRC government in 1958 to save the declining panda population, few advances in the conservation of pandas were made, due to inexperience and insufficient knowledge of ecology. Many believed that the best way to save the pandas was to cage them. As a result, pandas were caged at any sign of decline, and suffered from terrible conditions. Because of pollution and destruction of their natural habitat, along with segregation due to caging, reproduction of wild pandas was severely limited. In the 1990s, however, several laws (including gun control and the removal of resident humans from the reserves) helped the chances of survival for pandas. With these renewed efforts and improved conservation methods, wild pandas have started to increase in numbers in some areas, even though they still are classified as a rare species.
In 2006, scientists reported that the number of pandas living in the wild may have been underestimated at about 1,000. Previous population surveys had used conventional methods to estimate the size of the wild panda population, but using a new method that analyzes DNA from panda droppings, scientists believe that the wild panda population may be as large as 3,000.[21] Although the species is still endangered, it is thought that the conservation efforts are working. As of 2006, there were 40 panda reserves in China, compared to just 13 reserves two decades ago.
The Giant Panda is among the world's most adored and protected rare animals, and is one of the few in the world whose natural inhabitant status was able to gain a UNESCO World Heritage Site designation. The Sichuan Giant Panda Sanctuaries, located in the southwest Sichuan province and covering seven natural reserves, were inscribed onto the World Heritage List in 2006.[52][53]
Not all conservationists agree that the money spent on conserving pandas is money well spent. Chris Packham has argued that breeding pandas in captivity is "pointless" because "there is not enough habitat left to sustain them".[54] Packham argues that the money spent on pandas would be better spent elsewhere,[54] and has said that he would "eat the last panda if I could have all the money we have spent on panda conservation put back on the table for me to do more sensible things with," though he has apologized for upsetting people who like pandas.[56] He points out that "The panda is possibly one of the grossest wastes of conservation money in the last half century."
Reproduction
Initially the primary method of breeding Giant Pandas in captivity was by artificial insemination, as they seemed to lose their interest in mating once they were captured.[57] This led some scientists to try extreme methods such as showing them videos of giant Pandas mating[58] and giving the males Viagra.[59] Only recently have researchers started having success with captive breeding programs, and they have now determined that Giant Pandas have comparable breeding to some populations of the American Black Bear, a thriving bear family. The current reproductive rate is considered one young every two years.[12][22]
Giant Pandas reach sexual maturity between the ages of four and eight, and may be reproductive until age 20.[60] The mating season is between March and May, when a female goes into her estrous cycle which lasts for two or three days and only occurs once a year.[61] When mating, the female is in a crouching, head-down position as the male mounts her from behind. Copulation time is short, ranging from thirty seconds to five minutes, but the male may mount her repeatedly to ensure successful fertilization. The gestation period ranges from 95 to 160 days.[61] Cubs weigh only 90 to 130 grams (3.2 to 4.6 ounces), which is about 1/800 of the mother's weight. [36]
If twins are born, usually only one survives in the wild. The mother will select the stronger of the cubs, and the weaker will die. It is thought that the mother cannot produce enough milk for two cubs since she does not store fat.[62] The father has no part in helping raise the cub.
When the cub is first born, it is pink, blind, and toothless. [63] A Giant Panda cub is also extremely small, and it is difficult for the mother to protect it because of the baby's size. It nurses from its mother's breast 6 to 14 times a day for up to 30 minutes at a time. For three to four hours, the mother may leave the den to feed, which leaves the cub defenseless. One to two weeks after birth, the cub's skin turns gray where its hair will eventually become black. A slight pink color may appear on cub's fur, as a result of a chemical reaction between the fur and its mother's saliva. A month after birth, the color pattern of the cub's fur is fully developed. A cub's fur is very soft and coarsens with age. The cub begins to crawl at 75 to 80 days; [36] mothers play with their cubs by rolling and wrestling with them. The cubs are able to eat small quantities of bamboo after six months,[64] though mother's milk remains the primary food source for most of the first year. Giant Panda cubs weigh 45 kg (100 pounds) at one year, and live with their mothers until they are 18 months to two years old. The interval between births in the wild is generally two years.
In July 2009, Chinese scientists confirmed the birth of the first cub to be successfully conceived through artificial insemination using frozen sperm.[65] The cub was born at 07:41 on 23 July that year in Sichuan as the third cub of You You, an 11-year-old.[65][66][67] The technique for freezing the sperm in liquid nitrogen was first developed in 1980 and the first birth was hailed as a solution to the problem of lessening Giant Panda semen availability which had led to in-breeding.[67][68] It has been suggested that panda semen, which can be frozen for decades, could be shared between different zoos to save the species.[65][66] It is expected that zoos in destinations such as San Diego in the United States and Mexico City will now be able to provide their own semen to inseminate more Giant Pandas.[68]
Attempts have also been made to reproduce giant pandas by interspecific pregnancy by implanting cloned panda embryos into the uterus of an animal of another species. This has resulted in panda fetuses, but no live births.
Name
There is no conclusive explanation of the origin of the word "panda". The closest candidate is the Nepali word ponya, possibly referring to the adapted wrist bone. The Western world originally applied this name to the Red Panda. Until 1901, when it was erroneously stated that it was related to the Red Panda, the Giant Panda was known as "mottled bear" (Ailuropus melanoleucus) or "particolored bear".[70]
In most encyclopedic sources, the name "panda" or "common panda" originally referred to the lesser-known Red Panda,[71] thus necessitating the inclusion of "giant" and "lesser/red" prefixes in front of the names. Even as of 2010[update] the Encyclopædia Britannica still used "giant panda" or "panda bear" for the bear [72] and simply "panda" for the Ailuridae,[73] despite the popular usage of the word "panda".
Since the earliest collection of Chinese writings, the Chinese language has given the bear 20 different names, such as 花熊 (hua xiong) "spotted bear" and 竹熊 (zhu xiong) "bamboo bear".[74] The most popular names in China today are 大熊貓 (dà xióng māo), literally "large bear cat", or just 熊貓 (xióng māo), "bear cat". The name may have been inspired by the Giant Panda's eyes, which have pupils that are cat-like vertical slits - unlike other bear species, which have round pupils.[75]
In Taiwan, the popular name for panda is the inverted 貓熊 (māo xióng) "cat bear," even though many encyclopedia and dictionaries in Taiwan still use "bear cat" as the correct name. Some linguists argue that, in this construction, "bear" instead of "cat" is the base noun, making this name more grammatically and logically correct, which may have led to the popular choice despite official writings.
In zoos
See also: Category:Famous giant pandas
Pandas have been kept in zoos as early as the Western Han Dynasty in China, where the writer Sima Xiangru notes that the panda was the most treasured animal in the emperor's garden of exotic animals in Xi'an. Not until the 1950s were pandas again recorded to have been exhibited in China's zoos.[76]
A 2006 New York Times article[77] outlined the economics of keeping pandas, which costs five times more than that of the next most expensive animal, an elephant. American zoos generally pay the Chinese government $1 million a year in fees, as part of a typical ten-year contract. San Diego's contract with China was to expire in 2008 but got a five-year extension at about half of the previous yearly cost. The last contract, with the Memphis Zoo in Memphis, Tennessee, ends in 2013.
Thursday, January 20, 2011
Mariah Carey's incredible life and career
Posted on Jan 19, 2011
BBC Radio 1Xtra tells the story of Mariah Carey's incredible life and career, hearing from Mariah herself and some of her closest friends. Ronnie Herel narrates as 1Xtra reveals the person behind the glossy image and elaborate rumors, including quirky tales of Mariah both at work and away from the lime light. 1Xtra will trace her highs and lows, her struggles and comebacks and hear the stories behind the music that made her famous.
1Xtra’s: The Mariah Carey Story will air Sunday, January 23 at 9:00pm.
BBC Radio 1Xtra tells the story of Mariah Carey's incredible life and career, hearing from Mariah herself and some of her closest friends. Ronnie Herel narrates as 1Xtra reveals the person behind the glossy image and elaborate rumors, including quirky tales of Mariah both at work and away from the lime light. 1Xtra will trace her highs and lows, her struggles and comebacks and hear the stories behind the music that made her famous.
1Xtra’s: The Mariah Carey Story will air Sunday, January 23 at 9:00pm.
Wednesday, January 19, 2011
 | The Company Men (2010)
The story centers on a year in the life of three men trying to survive a round of corporate downsizing at a major company - and how that affects them, their families, and their communities. Director:John WellsWriter:John Wells |
109 min - Friday, January 7, 2011
Amazing Balance Trick!
Amazing Balance Trick!
Impossible motion: magnet-like slopes
Jared Leto Look | Cosplay
Monday, January 3, 2011
How are solar panels are made?
How are solar panels made?
Discover the process of making a solar panel
Making solar panels is a delicate process, and it is for this reason that major solar advances did not come into play until the lattermost quarter of the last century, when advances in semiconductors and photovoltaic design allowed increasingly efficient and affordable solar cells to be developed.
Crystalline Silicon Solar Panels
The creation of solar panels typically involves cutting crystalline silicon into tiny disks less than a centimeter thick. These thin, wafer-like disks are then carefully polished and treated to repair and gloss any damage from the slicing process. After polishing, dopants (materials added to alter an electrical charge in a semiconductor or photovoltaic solar cell) and metal conductors are spread across each disk. The conductors are aligned in a thin, grid-like matrix on the top of the solar panel, and are spread in a flat, thin sheet on the side facing the earth.
 | To protect the solar panels after processing, a thin layer of cover glass is then bonded to the top of the photovoltaic cell. After the bonding of protective glass, the nearly-finished panel is attached to a subtrate by an expensive, thermally conductive cement. The thermally conductive property of the cement keep the solar panel from becoming overheated; any leftover energy that the solar panel is unable to convert to electricity would otherwise overheat the unit and reduce the efficiency of the solar cells. |
Despite these protective measures against the tendancy of solar panels to overheat, it is vital that when installing a solar panel, additional steps should be taken to ensure the solar panel is kept cool. Elevating the solar panel above ground (see solar panel mounts) to let the airflow underneath cool the device.
Amorphous Silicon Solar Panels
Amorphous silicon solar panels are a powerful, emerging line of photovoltaics, that differ in output, structure, and manufacture than traditional photovoltaics which use crystalline silicon. Amorphous silicon solar cells, or A-si cells, are developed in a continuous roll-to-roll process by vapor-depositing silicon alloys in multiple layers, with each extremely thin layer specializing in the absorption of different parts of the solar spectrum. The result is record-breaking efficiency and reduced materials cost (A-si solar cells are typically thinner than their crystalline counterparts).
Some Amorphous Solar Panels also come with shade-resistant technology or multiple circuits within the cells, so that if an entire row of cells is subject to complete shading, the circuit won't be completely broken and some output can still be gained. This is especially useful when installing solar panels on a boat.
The development process of Amorphous Silicon solar panels also renders them much less susceptible to breakage during transport or installation. This can help reduce the risk of damaging your significant investment in a photovoltaic system. Click here for more more information on amorphous silicon solar panels.
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