title: "Pan flute" content: Greeks and the Etruscans, and they too played it at their banquets, festivals, as well as in religious and funeral processions. The pan flute's tubes are stopped at one end, at which the standing wave is reflected giving a note an octave lower than that produced by an open pipe of equal length. In the traditional South American style, pipes are fine-tuned to correct pitch by placing small pebbles or dry corn kernels into the bottom of the pipes. Contemporary makers of curved Romanian-style panpipes use wax (commonly beeswax) to tune new instruments. Special tools are used to place or


title: "Pan flute" content: remove the wax. Corks and rubber stoppers are also used, and are easier to quickly tune pipes. The pan flute is an end-blown flute. Sound is produced by the vibration of an air-stream blowing across an open hole at the end of a resonating tube. The length of the tube determines the fundamental frequency. An overblown harmonic register is near a 12th above the fundamental in cylindrical tubes, but can approach an octave jump (8th) if a decreasing taper is used. According to the Fundamental Principle for pan flutes, the frequency and the length of the tube are inversely proportional.


title: "Pan flute" content: Every time the pitch goes up one octave, the frequency doubles. Because there are 12 notes in a chromatic scale or a full octave, every half-step in a chromatic scale is multiplied by the 12th root of 2 to get the note next to it. By this, it is possible to calculate the length of any pipe, given that one knows the length of any one pipe. The formula for calculating the length of a pan flute pipe is L = (c / f) / 4 (the "theoretical length" L equals the speed of sound c = 343 m/s, divided


title: "Pan flute" content: by the desired frequency in hertz f, that quantity divided by 4; this simplifies and rearranges to: Length of pipe (in centimeters) × Frequency (in hertz) = 8575). Because of a property of compression within the tube, the length must be a little shorter to correct flat pitch. The extra length is helpful for a maker, who can use a cork or plug at the bottom to adjust the pitch. Some instruments use wax or pellets to tune the fundamental pitch of each tube. A tube that has a diameter 1/10 of its length yields a typical tone colour (see


title: "Pan flute" content: Timbre). An inner diameter range between 1/7 and 1/14 of the length L is acceptable. A narrow tube will sound "reedy", while a wide one will sound "flutey". A more exact method is to multiply the bore diameter by 0.82 and subtract this value from the tube length. This compensates for internal compression slowing frequency and the lips partially covering the voicing. Only tiny adjustments will be needed then to adjust fundamental pitch for air density and temperature. The pan flute is played by blowing horizontally across an open end against the sharp inner edge of the pipes. Each pipe


title: "Pan flute" content: is tuned to a keynote, called the fundamental frequency. By overblowing, that is, increasing the pressure of breath and tension of lips, odd harmonics (notes whose frequencies are odd-number multiples of the fundamental), near a 12th in cylindrical tubes, may also be produced. The Romanian pan flute has the pipes arranged in a curved array, solidly glued together, unlike Andean versions, which are usually tied together. Thus, the player can easily reach all the notes by simply swiveling the head, or by moving the instrument with the hands. These instruments can also play all the sharps and flats, with a


title: "Pan flute" content: special technique of both tilting the pipes and jaw movement, thus reducing the size of the pipe's opening and producing a change in pitch. A very advanced player can play any scale and in any key. There are two styles of vibrato possible, hand vibrato and breath vibrato. In hand vibrato, the pitch is shifted up and down, like a vocal vibrato. The player gently moves one end of the pan flute (usually the high end) somewhat similar to violin vibrato. Breath, or throat vibrato, which is really tremelo, a shift in volume, is the same technique used by players


title: "Pan flute" content: of the flute and other woodwinds by use of the player's diaphragm, or throat muscles. The curved-style pan flute was popularized by the Romanian musician Gheorghe Zamfir, who toured extensively and recorded many albums of pan flute music in the 1970s, and by several other artists who began recording at the same time. Today there are thousands of devoted players across Europe, Asia and the Americas. Both the curved and traditional South American variations are also very popular in Peruvian traditional groups and other Andean music. In Laos and Thailand, there is a cylindrical version called the wot, used in


title: "Pan flute" content: folk music from the Isaan region of the country. The player alters notes by rotating the instrument with the hands, rather than by head movements. Some new designs are beginning to appear, as designers and makers take advantage of computer-aided design and 3D additive manufacturing, to move past the limitations of traditional tool and materials. These new pan flutes address some long-standing issues to make it an easier instrument to learn and to play accurately. Notable pan flute musicians: Pan flute The pan flutes (also known as panpipes or syrinx) are a group of musical instruments based on the principle


title: "Pope Victor II" content: Almodis, countess of Limoges, for adultery, at the behest of Ermesinde of Carcassonne, in 1055. In June 1055, Victor met the Emperor at Florence and held a council, which reinforced Pope Leo IX's condemnation of clerical marriage, simony, and the loss of the church's properties. In the following year, he was summoned to the Emperor's side, and was with Henry III when he died at Bodfeld in the Harz on 5 October 1056. As guardian of Henry III's infant son Henry and adviser of the Empress Agnes, Henry IV's mother, Victor II now wielded enormous power, which he used to


title: "Polar bear" content: Polar bear The polar bear ("Ursus maritimus") is a hypercarnivorous bear whose native range lies largely within the Arctic Circle, encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is a large bear, approximately the same size as the omnivorous Kodiak bear ("Ursus arctos middendorffi"). A boar (adult male) weighs around , while a sow (adult female) is about half that size. Although it is the sister species of the brown bear, it has evolved to occupy a narrower ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice and open water,


title: "Polar bear" content: and for hunting seals, which make up most of its diet. Although most polar bears are born on land, they spend most of their time on the sea ice. Their scientific name means "maritime bear" and derives from this fact. Polar bears hunt their preferred food of seals from the edge of sea ice, often living off fat reserves when no sea ice is present. Because of their dependence on the sea ice, polar bears are classified as marine mammals. Because of expected habitat loss caused by climate change, the polar bear is classified as a vulnerable species, and at


title: "Polar bear" content: least three of the nineteen polar bear subpopulations are currently in decline. However, at least two of the nineteen subpopulations are currently increasing, while another six are considered stable. For decades, large-scale hunting raised international concern for the future of the species, but populations rebounded after controls and quotas began to take effect. For thousands of years, the polar bear has been a key figure in the material, spiritual, and cultural life of circumpolar peoples, and polar bears remain important in their cultures. Historically, the polar bear has also been known as the white bear. Constantine John Phipps was the


title: "Polar bear" content: first to describe the polar bear as a distinct species in 1774. He chose the scientific name "Ursus maritimus", the Latin for 'maritime bear', due to the animal's native habitat. The Inuit refer to the animal as "nanook" (transliterated as "nanuq" in the Inupiat language). The Yupik also refer to the bear as "nanuuk" in Siberian Yupik. The bear is "umka" in the Chukchi language. In Russian, it is usually called бе́лый медве́дь ("bélyj medvédj", the white bear), though an older word still in use is ошку́й ("Oshkúj", which comes from the Komi "oski", "bear"). In Quebec, the polar bear


title: "Polar bear" content: is referred to as "ours blanc" ("white bear") or "ours polaire" ("polar bear"). In the Norwegian-administered Svalbard archipelago, the polar bear is referred to as "Isbjørn" ("ice bear"). The polar bear was previously considered to be in its own genus, "Thalarctos". However, evidence of hybrids between polar bears and brown bears, and of the recent evolutionary divergence of the two species, does not support the establishment of this separate genus, and the accepted scientific name is now therefore "Ursus maritimus", as Phipps originally proposed. The bear family, Ursidae, is thought to have split from other carnivorans about 38 million years


title: "Polar bear" content: ago. The subfamily Ursinae originated approximately 4.2 million years ago. The oldest known polar bear fossil is a 130,000 to 110,000-year-old jaw bone, found on Prince Charles Foreland in 2004. Fossils show that between 10,000 and 20,000 years ago, the polar bear's molar teeth changed significantly from those of the brown bear. Polar bears are thought to have diverged from a population of brown bears that became isolated during a period of glaciation in the Pleistocene from the eastern part of Siberia (from Kamchatka and the Kolym Peninsula). The evidence from DNA analysis is more complex. The mitochondrial DNA (mtDNA)


title: "Polar bear" content: of the polar bear diverged from the brown bear, "Ursus arctos", roughly 150,000 years ago. Further, some clades of brown bear, as assessed by their mtDNA, are more closely related to polar bears than to other brown bears, meaning that the polar bear might not be considered a species under some species concepts. The mtDNA of extinct Irish brown bears is particularly close to polar bears. A comparison of the nuclear genome of polar bears with that of brown bears revealed a different pattern, the two forming genetically distinct clades that diverged approximately 603,000 years ago, although the latest research


title: "Polar bear" content: is based on analysis of the complete genomes (rather than just the mitochondria or partial nuclear genomes) of polar and brown bears, and establishes the divergence of polar and brown bears at 400,000 years ago. However, the two species have mated intermittently for all that time, most likely coming into contact with each other during warming periods, when polar bears were driven onto land and brown bears migrated northward. Most brown bears have about 2 percent genetic material from polar bears, but one population, the ABC Islands bears has between 5 percent and 10 percent polar bear genes, indicating more


title: "Polar bear" content: frequent and recent mating. Polar bears can breed with brown bears to produce fertile grizzly–polar bear hybrids, rather than indicating that they have only recently diverged, the new evidence suggests more frequent mating has continued over a longer period of time, and thus the two bears remain genetically similar. However, because neither species can survive long in the other's ecological niche, and because they have different morphology, metabolism, social and feeding behaviours, and other phenotypic characteristics, the two bears are generally classified as separate species. When the polar bear was originally documented, two subspecies were identified: "Ursus maritimus maritimus" by


title: "Polar bear" content: Constantine J. Phipps in 1774, and "Ursus maritimus marinus" by Peter Simon Pallas in 1776. This distinction has since been invalidated. One alleged fossil subspecies has been identified: "Ursus maritimus tyrannus" became extinct during the Pleistocene. "U.m. tyrannus" was significantly larger than the living subspecies. However, recent reanalysis of the fossil suggests that it was actually a type of brown bear. The polar bear is found in the Arctic Circle and adjacent land masses as far south as Newfoundland. Due to the absence of human development in its remote habitat, it retains more of its original range than any other


title: "Polar bear" content: extant carnivore. While they are rare north of 88°, there is evidence that they range all the way across the Arctic, and as far south as James Bay in Canada. Their southernmost range is near the boundary between the subarctic and humid continental climate zones. They can occasionally drift widely with the sea ice, and there have been anecdotal sightings as far south as Berlevåg on the Norwegian mainland and the Kuril Islands in the Sea of Okhotsk. It is difficult to estimate a global population of polar bears as much of the range has been poorly studied; however, biologists


title: "Polar bear" content: use a working estimate of about 20–25,000 or 22–31,000 polar bears worldwide. There are 19 generally recognized, discrete subpopulations, though polar bears are thought to exist only in low densities in the area of the Arctic Basin. The subpopulations display seasonal fidelity to particular areas, but DNA studies show that they are not reproductively isolated. The thirteen North American subpopulations range from the Beaufort Sea south to Hudson Bay and east to Baffin Bay in western Greenland and account for about 54% of the global population. The range includes the territory of five nations: Denmark (Greenland), Norway (Svalbard), Russia, the


title: "Polar bear" content: United States (Alaska) and Canada. These five nations are the signatories of the International Agreement on the Conservation of Polar Bears, which mandates cooperation on research and conservation efforts throughout the polar bear's range. Bears sometimes swim to Iceland from Greenland—about 600 sightings since the country's settlement in the 9th century AD, and five in the 21st century —and are always killed because of their danger, and the cost and difficulty of repatriation. Modern methods of tracking polar bear populations have been implemented only since the mid-1980s, and are expensive to perform consistently over a large area. The most accurate


title: "Polar bear" content: counts require flying a helicopter in the Arctic climate to find polar bears, shooting a tranquilizer dart at the bear to sedate it, and then tagging the bear. In Nunavut, some Inuit have reported increases in bear sightings around human settlements in recent years, leading to a belief that populations are increasing. Scientists have responded by noting that hungry bears may be congregating around human settlements, leading to the illusion that populations are higher than they actually are. The Polar Bear Specialist Group of the IUCN Species Survival Commission takes the position that "estimates of subpopulation size or sustainable harvest


title: "Polar bear" content: levels should not be made solely on the basis of traditional ecological knowledge without supporting scientific studies." Of the 19 recognized polar bear subpopulations, three are declining, six are stable, one is increasing, and nine have insufficient data, as of 2014. The polar bear is a marine mammal because it spends many months of the year at sea. However, it is the only living marine mammal with powerful, large limbs and feet that allow them to cover miles on foot and run on land. Its preferred habitat is the annual sea ice covering the waters over the continental shelf and


title: "Polar bear" content: the Arctic inter-island archipelagos. These areas, known as the "Arctic ring of life", have high biological productivity in comparison to the deep waters of the high Arctic. The polar bear tends to frequent areas where sea ice meets water, such as polynyas and leads (temporary stretches of open water in Arctic ice), to hunt the seals that make up most of its diet. Freshwater is limited in these environments because it is either locked up in snow or saline. Polar bears are able to produce water through the metabolism of fats found in seal blubber. Polar bears are therefore found


title: "Polar bear" content: primarily along the perimeter of the polar ice pack, rather than in the Polar Basin close to the North Pole where the density of seals is low. Annual ice contains areas of water that appear and disappear throughout the year as the weather changes. Seals migrate in response to these changes, and polar bears must follow their prey. In Hudson Bay, James Bay, and some other areas, the ice melts completely each summer (an event often referred to as "ice-floe breakup"), forcing polar bears to go onto land and wait through the months until the next freeze-up. In the Chukchi


title: "Polar bear" content: and Beaufort seas, polar bears retreat each summer to the ice further north that remains frozen year-round. The only other bear similar in size to the polar bear is the Kodiak bear, which is a subspecies of brown bear. Adult male polar bears weigh and measure in total length. Around the Beaufort Sea, however, mature males reportedly average . Adult females are roughly half the size of males and normally weigh , measuring in length. Elsewhere, a slightly larger estimated average weight of was claimed for adult females. When pregnant, however, females can weigh as much as . The polar


title: "Polar bear" content: bear is among the most sexually dimorphic of mammals, surpassed only by the pinnipeds such as elephant seals. The largest polar bear on record, reportedly weighing , was a male shot at Kotzebue Sound in northwestern Alaska in 1960. This specimen, when mounted, stood tall on its hindlegs. The shoulder height of an adult polar bear is . While all bears are short-tailed, the polar bear's tail is relatively the shortest amongst living bears, ranging from in length. Compared with its closest relative, the brown bear, the polar bear has a more elongated body build and a longer skull and


title: "Polar bear" content: nose. As predicted by Allen's rule for a northerly animal, the legs are stocky and the ears and tail are small. However, the feet are very large to distribute load when walking on snow or thin ice and to provide propulsion when swimming; they may measure across in an adult. The pads of the paws are covered with small, soft papillae (dermal bumps), which provide traction on the ice. The polar bear's claws are short and stocky compared to those of the brown bear, perhaps to serve the former's need to grip heavy prey and ice. The claws are deeply


title: "Polar bear" content: scooped on the underside to assist in digging in the ice of the natural habitat. Research of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. Unlike the brown bear, polar bears in captivity are rarely overweight or particularly large, possibly as a reaction to the warm conditions of most zoos. The 42 teeth of a polar bear reflect its highly carnivorous diet. The cheek teeth are smaller and more jagged than in the brown bear, and the canines are larger and sharper. The dental


title: "Polar bear" content: formula is Polar bears are superbly insulated by up to of adipose tissue, their hide and their fur; they overheat at temperatures above , and are nearly invisible under infrared photography. Polar bear fur consists of a layer of dense underfur and an outer layer of guard hairs, which appear white to tan but are actually transparent. Two genes that are known to influence melanin production, LYST and AIM1, are both mutated in polar bears, possibly leading to the absence on this pigment in their fur. The guard hair is over most of the body. Polar bears gradually moult from


title: "Polar bear" content: May to August, but, unlike other Arctic mammals, they do not shed their coat for a darker shade to provide camouflage in summer conditions. The hollow guard hairs of a polar bear coat were once thought to act as fiber-optic tubes to conduct light to its black skin, where it could be absorbed; however, this hypothesis was disproved by a study in 1998. The white coat usually yellows with age. When kept in captivity in warm, humid conditions, the fur may turn a pale shade of green due to algae growing inside the guard hairs. Males have significantly longer hairs


title: "Polar bear" content: on their forelegs, which increase in length until the bear reaches 14 years of age. The male's ornamental foreleg hair is thought to attract females, serving a similar function to the lion's mane. The polar bear has an extremely well developed sense of smell, being able to detect seals nearly away and buried under of snow. Its hearing is about as acute as that of a human, and its vision is also good at long distances. The polar bear is an excellent swimmer and often will swim for days. One bear swam continuously for 9 days in the frigid Bering


title: "Polar bear" content: Sea for to reach ice far from land. She then travelled another . During the swim, the bear lost 22% of her body mass and her yearling cub died. With its body fat providing buoyancy, the bear swims in a dog paddle fashion using its large forepaws for propulsion. Polar bears can swim . When walking, the polar bear tends to have a lumbering gait and maintains an average speed of around . When sprinting, they can reach up to . Unlike brown bears, polar bears are not territorial. Although stereotyped as being voraciously aggressive, they are normally cautious in


title: "Polar bear" content: confrontations, and often choose to escape rather than fight. Satiated polar bears rarely attack humans unless severely provoked. However, due to their lack of prior human interaction, hungry polar bears are extremely unpredictable, fearless towards people and are known to kill and sometimes eat humans. Many attacks by brown bears are the result of surprising the animal, which is not the case with the polar bear. Polar bears are stealth hunters, and the victim is often unaware of the bear's presence until the attack is underway. Whereas brown bears often maul a person and then leave, polar bear attacks are


title: "Polar bear" content: more likely to be predatory and are almost always fatal. However, due to the very small human population around the Arctic, such attacks are rare. Michio Hoshino, a Japanese wildlife photographer, was once pursued briefly by a hungry male polar bear in northern Alaska. According to Hoshino, the bear started running but Hoshino made it to his truck. The bear was able to reach the truck and tore one of the doors off the truck before Hoshino was able to drive off. In general, adult polar bears live solitary lives. Yet, they have often been seen playing together for hours


title: "Polar bear" content: at a time and even sleeping in an embrace, and polar bear zoologist Nikita Ovsianikov has described adult males as having "well-developed friendships." Cubs are especially playful as well. Among young males in particular, play-fighting may be a means of practicing for serious competition during mating seasons later in life. Polar bears are usually quiet but do communicate with various sounds and vocalizations. Females communicate with their young with moans and chuffs, and the distress calls of both cubs and subadults consists of bleats. Cubs may hum while nursing. When nervous, bears produce huffs, chuffs and snorts while hisses, growls


title: "Polar bear" content: and roars are signs of aggression. Chemical communication can also be important: bears leave behind their scent in their tracks which allow individuals to keep track of one another in the vast Arctic wilderness. In 1992, a photographer near Churchill took a now widely circulated set of photographs of a polar bear playing with a Canadian Eskimo Dog ("Canis lupus familiaris") a tenth of its size. The pair wrestled harmlessly together each afternoon for ten days in a row for no apparent reason, although the bear may have been trying to demonstrate its friendliness in the hope of sharing the


title: "Polar bear" content: kennel's food. This kind of social interaction is uncommon; it is far more typical for polar bears to behave aggressively towards dogs. The polar bear is the most carnivorous member of the bear family, and throughout most of its range, its diet primarily consists of ringed ("Pusa hispida") and bearded seals ("Erignathus barbatus"). The Arctic is home to millions of seals, which become prey when they surface in holes in the ice in order to breathe, or when they haul out on the ice to rest. Polar bears hunt primarily at the interface between ice, water, and air; they only


title: "Polar bear" content: rarely catch seals on land or in open water. The polar bear's most common hunting method is called "still-hunting": the bear uses its excellent sense of smell to locate a seal breathing hole, and crouches nearby in silence for a seal to appear. The bear may lay in wait for several hours. When the seal exhales, the bear smells its breath, reaches into the hole with a forepaw, and drags it out onto the ice. The polar bear kills the seal by biting its head to crush its skull. The polar bear also hunts by stalking seals resting on the


title: "Polar bear" content: ice: upon spotting a seal, it walks to within , and then crouches. If the seal does not notice, the bear creeps to within of the seal and then suddenly rushes forth to attack. A third hunting method is to raid the birth lairs that female seals create in the snow. A widespread legend tells that polar bears cover their black noses with their paws when hunting. This behaviour, if it happens, is rare – although the story exists in the oral history of northern peoples and in accounts by early Arctic explorers, there is no record of an eyewitness


title: "Polar bear" content: account of the behaviour in recent decades. Mature bears tend to eat only the calorie-rich skin and blubber of the seal, which are highly digestible, whereas younger bears consume the protein-rich red meat. Studies have also photographed polar bears scaling near-vertical cliffs, to eat birds' chicks and eggs. For subadult bears, which are independent of their mother but have not yet gained enough experience and body size to successfully hunt seals, scavenging the carcasses from other bears' kills is an important source of nutrition. Subadults may also be forced to accept a half-eaten carcass if they kill a seal but


title: "Polar bear" content: cannot defend it from larger polar bears. After feeding, polar bears wash themselves with water or snow. Although polar bears are extraordinarily powerful, its primary prey species, the ringed seal, is much smaller than itself, and many of the seals hunted are pups rather than adults. Ringed seals are born weighing and grown to an estimated average weight of only . They also in places prey heavily upon the harp seal ("Pusa groenlandica") or the harbor seal. The bearded seal, on the other hand, can be nearly the same size as the bear itself, averaging . Adult male bearded seals,


title: "Polar bear" content: at are too large for a female bear to overtake, and so are potential prey only for mature male bears. Large males also occasionally attempt to hunt and kill even larger prey items. It can kill an adult walrus ("Odobenus rosmarus"), although this is rarely attempted. At up to and a typical adult mass range of , a walrus can be more than twice the bear's weight, and has up to -long ivory tusks that can be used as formidable weapons. A polar bear may charge a group of walruses, with the goal of separating a young, infirm, or injured


title: "Polar bear" content: walrus from the pod. They will even attack adult walruses when their diving holes have frozen over or intercept them before they can get back to the diving hole in the ice. Yet, polar bears will very seldom attack full-grown adult walruses, with the largest male walrus probably invulnerable unless otherwise injured or incapacitated. Since an attack on a walrus tends to be an extremely protracted and exhausting venture, bears have been known to back down from the attack after making the initial injury to the walrus. Polar bears have also been seen to prey on beluga whales ("Delphinapterus leucas")


title: "Polar bear" content: and narwhals ("Monodon monoceros"), by swiping at them at breathing holes. The whales are of similar size to the walrus and nearly as difficult for the bear to subdue. Most terrestrial animals in the Arctic can outrun the polar bear on land as polar bears overheat quickly, and most marine animals the bear encounters can outswim it. In some areas, the polar bear's diet is supplemented by walrus calves and by the carcasses of dead adult walruses or whales, whose blubber is readily devoured even when rotten. Polar bears sometimes swim underwater to catch fish like the Arctic charr or


title: "Polar bear" content: the fourhorn sculpin. With the exception of pregnant females, polar bears are active year-round, although they have a vestigial hibernation induction trigger in their blood. Unlike brown and black bears, polar bears are capable of fasting for up to several months during late summer and early fall, when they cannot hunt for seals because the sea is unfrozen. When sea ice is unavailable during summer and early autumn, some populations live off fat reserves for months at a time, as polar bears do not 'hibernate' any time of the year. Being both curious animals and scavengers, polar bears investigate and


title: "Polar bear" content: consume garbage where they come into contact with humans. Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. The dump in Churchill, Manitoba was closed in 2006 to protect bears, and waste is now recycled or transported to Thompson, Manitoba. Although seal predation is the primary and an indispensable way of life for most polar bears, when alternatives are present they are quite flexible. Polar bears consume a wide variety of other wild foods, including muskox ("Ovibos moschatus"), reindeer ("Rangifer tarandus"), birds,


title: "Polar bear" content: eggs, rodents, crabs, other crustaceans and other polar bears. They may also eat plants, including berries, roots, and kelp; however, none of these have been a significant part of their diet, except for beachcast marine mammal carcasses. Given the change in climate, with ice breaking up in areas such as the Hudson Bay earlier than it used to, polar bears are exploiting food resources such as snow geese and eggs, and plants such as lyme grass in increased quantities. When stalking land animals, such as muskox, reindeer, and even willow ptarmigan ("Lagopus lagopus"), polar bears appear to make use of


title: "Polar bear" content: vegetative cover and wind direction to bring them as close to their prey as possible before attacking. Polar bears have been observed to hunt the small Svalbard reindeer ("R. t. platyrhynchus"), which weigh only as adults, as well as the barren-ground caribou ("R. t. groenlandicus"), which is about twice as heavy as that. Adult muskox, which can weigh or more, are a more formidable quarry. Although ungulates are not typical prey, the killing of one during the summer months can greatly increase the odds of survival during that lean period. Like the brown bear, most ungulate prey of polar bears


title: "Polar bear" content: is likely to be young, sickly or injured specimens rather than healthy adults. The polar bear's metabolism is specialized to require large amounts of fat from marine mammals, and it cannot derive sufficient caloric intake from terrestrial food. In their southern range, especially near Hudson Bay and James Bay, Canadian polar bears endure all summer without sea ice to hunt from. Here, their food ecology shows their dietary flexibility. They still manage to consume some seals, but they are food-deprived in summer as only marine mammal carcasses are an important alternative without sea ice, especially carcasses of the beluga whale.


title: "Polar bear" content: These alternatives may reduce the rate of weight loss of bears when on land. One scientist found that 71% of the Hudson Bay bears had fed on seaweed (marine algae) and that about half were feeding on birds such as the dovekie and sea ducks, especially the long-tailed duck (53%) and common eider, by swimming underwater to catch them. They were also diving to feed on blue mussels and other underwater food sources like the green sea urchin. 24% had eaten moss recently, 19% had consumed grass, 34% had eaten black crowberry and about half had consumed willows. This study


title: "Polar bear" content: illustrates the polar bear's dietary flexibility but it does not represent its life history elsewhere. Most polar bears elsewhere will never have access to these alternatives, except for the marine mammal carcasses that are important wherever they occur. In Svalbard, polar bears were observed to kill white-beaked dolphins during spring, when the dolphins were trapped in the sea ice. The bears then proceeded to cache the carcasses, which remained and were eaten during the ice-free summer and autumn. Courtship and mating take place on the sea ice in April and May, when polar bears congregate in the best seal hunting


title: "Polar bear" content: areas. A male may follow the tracks of a breeding female for or more, and after finding her engage in intense fighting with other males over mating rights, fights that often result in scars and broken teeth. Polar bears have a generally polygynous mating system; recent genetic testing of mothers and cubs, however, has uncovered cases of litters in which cubs have different fathers. Partners stay together and mate repeatedly for an entire week; the mating ritual induces ovulation in the female. After mating, the fertilized egg remains in a suspended state until August or September. During these four months,


title: "Polar bear" content: the pregnant female eats prodigious amounts of food, gaining at least and often more than doubling her body weight. When the ice floes are at their minimum in the fall, ending the possibility of hunting, each pregnant female digs a "maternity den" consisting of a narrow entrance tunnel leading to one to three chambers. Most maternity dens are in snowdrifts, but may also be made underground in permafrost if it is not sufficiently cold yet for snow. In most subpopulations, maternity dens are situated on land a few kilometers from the coast, and the individuals in a subpopulation tend to


title: "Polar bear" content: reuse the same denning areas each year. The polar bears that do not den on land make their dens on the sea ice. In the den, she enters a dormant state similar to hibernation. This hibernation-like state does not consist of continuous sleeping; however, the bear's heart rate slows from 46 to 27 beats per minute. Her body temperature does not decrease during this period as it would for a typical mammal in hibernation. Between November and February, cubs are born blind, covered with a light down fur, and weighing less than , but in captivity they might be delivered


title: "Polar bear" content: in the earlier months. The earliest recorded birth of polar bears in captivity was on 11 October 2011 in the Toronto Zoo. On average, each litter has two cubs. The family remains in the den until mid-February to mid-April, with the mother maintaining her fast while nursing her cubs on a fat-rich milk. By the time the mother breaks open the entrance to the den, her cubs weigh about . For about 12 to 15 days, the family spends time outside the den while remaining in its vicinity, the mother grazing on vegetation while the cubs become used to walking


title: "Polar bear" content: and playing. Then they begin the long walk from the denning area to the sea ice, where the mother can once again catch seals. Depending on the timing of ice-floe breakup in the fall, she may have fasted for up to eight months. During this time, cubs playfully imitate the mother's hunting methods in preparation for later life. Female polar bears are noted for both their affection towards their offspring, and their valor in protecting them. Multiple cases of adoption of wild cubs have been confirmed by genetic testing. Adult male bears occasionally kill and eat polar bear cubs. As


title: "Polar bear" content: of 2006, in Alaska, 42% of cubs were reaching 12 months of age, down from 65% in 1991. In most areas, cubs are weaned at two and a half years of age, when the mother chases them away or abandons them. The Western Hudson Bay subpopulation is unusual in that its female polar bears sometimes wean their cubs at only one and a half years. This was the case for 40% of cubs there in the early 1980s; however by the 1990s, fewer than 20% of cubs were weaned this young. After the mother leaves, sibling cubs sometimes travel and


title: "Polar bear" content: share food together for weeks or months. Females begin to breed at the age of four years in most areas, and five years in the Beaufort Sea area. Males usually reach sexual maturity at six years; however, as competition for females is fierce, many do not breed until the age of eight or ten. A study in Hudson Bay indicated that both the reproductive success and the maternal weight of females peaked in their mid-teens. Polar bears appear to be less affected by infectious diseases and parasites than most terrestrial mammals. Polar bears are especially susceptible to "Trichinella", a parasitic


title: "Polar bear" content: roundworm they contract through cannibalism, although infections are usually not fatal. Only one case of a polar bear with rabies has been documented, even though polar bears frequently interact with Arctic foxes, which often carry rabies. Bacterial leptospirosis and "Morbillivirus" have been recorded. Polar bears sometimes have problems with various skin diseases that may be caused by mites or other parasites. Polar bears rarely live beyond 25 years. The oldest wild bears on record died at age 32, whereas the oldest captive was a female who died in 1991, age 43. The causes of death in wild adult polar bears


title: "Polar bear" content: are poorly understood, as carcasses are rarely found in the species's frigid habitat. In the wild, old polar bears eventually become too weak to catch food, and gradually starve to death. Polar bears injured in fights or accidents may either die from their injuries or become unable to hunt effectively, leading to starvation. The polar bear is the apex predator within its range, and is a keystone species for the Arctic. Several animal species, particularly Arctic foxes ("Vulpes lagopus") and glaucous gulls ("Larus hyperboreus"), routinely scavenge polar bear kills. The relationship between ringed seals and polar bears is so close


title: "Polar bear" content: that the abundance of ringed seals in some areas appears to regulate the density of polar bears, while polar bear predation in turn regulates density and reproductive success of ringed seals. The evolutionary pressure of polar bear predation on seals probably accounts for some significant differences between Arctic and Antarctic seals. Compared to the Antarctic, where there is no major surface predator, Arctic seals use more breathing holes per individual, appear more restless when hauled out on the ice, and rarely defecate on the ice. The baby fur of most Arctic seal species is white, presumably to provide camouflage from


title: "Polar bear" content: predators, whereas Antarctic seals all have dark fur at birth. Brown bears tend to dominate polar bears in disputes over carcasses, and dead polar bear cubs have been found in brown bear dens. Wolves are rarely encountered by polar bears, though there are two records of Arctic wolf ("Canis lupus arctos") packs killing polar bear cubs. Adult polar bears are occasionally vulnerable to predation by orcas ("Orcinus orca") while swimming, but they are rarely reported as taken and bears are likely to avoid entering the water if possible if they detect an orca pod in the area. The melting sea


title: "Polar bear" content: ice in the Arctic may be causing an increase of orcas in the Arctic sea, which may increase the risk of predation on polar bears but also may benefit the bears by providing more whale carcasses that they can scavenge. The remains of polar bears have found in the stomachs of large Greenland sharks ("Somniosus microcephalus"), although it certainly cannot be ruled out that the bears were merely scavenged by this slow-moving, unusual shark. A rather unlikely killer of a grown polar bear has reportedly included a wolverine ("Gulo gulo"), anecedotely reported to have suffocated a bear in a zoo


title: "Polar bear" content: with a bite to the throat during a conflict. This report may well be dubious, however. Polar bears are sometimes the host of arctic mites such as "Alaskozetes antarcticus". Researchers tracked 52 sows in the southern Beaufort Sea off Alaska with GPS system collars; no boars were involved in the study due to males' necks being too thick for the GPS-equipped collars. Fifty long-distance swims were recorded; the longest at , with an average of . The length of these swims ranged from most of a day to ten days. Ten of the sows had a cub swim with them


title: "Polar bear" content: and after a year, six cubs survived. The study did not determine if the others lost their cubs before, during, or some time after their long swims. Researchers do not know whether or not this is a new behaviour; before polar ice shrinkage, they opined that there was probably neither the need nor opportunity to swim such long distances. The polar bear may swim underwater for up to three minutes to approach seals on shore or on ice floes. Polar bears have long provided important raw materials for Arctic peoples, including the Inuit, Yupik, Chukchi, Nenets, Russian Pomors and others.


title: "Polar bear" content: Hunters commonly used teams of dogs to distract the bear, allowing the hunter to spear the bear or shoot it with arrows at closer range. Almost all parts of captured animals had a use. The fur was used in particular to make trousers and, by the Nenets, to make galoshes-like outer footwear called "tobok"; the meat is edible, despite some risk of trichinosis; the fat was used in food and as a fuel for lighting homes, alongside seal and whale blubber; sinews were used as thread for sewing clothes; the gallbladder and sometimes heart were dried and powdered for medicinal


title: "Polar bear" content: purposes; the large canine teeth were highly valued as talismans. Only the liver was not used, as its high concentration of vitamin A is poisonous. Hunters make sure to either toss the liver into the sea or bury it in order to spare their dogs from potential poisoning. Traditional subsistence hunting was on a small enough scale to not significantly affect polar bear populations, mostly because of the sparseness of the human population in polar bear habitat. In Russia, polar bear furs were already being commercially traded in the 14th century, though it was of low value compared to Arctic


title: "Polar bear" content: fox or even reindeer fur. The growth of the human population in the Eurasian Arctic in the 16th and 17th century, together with the advent of firearms and increasing trade, dramatically increased the harvest of polar bears. However, since polar bear fur has always played a marginal commercial role, data on the historical harvest is fragmentary. It is known, for example, that already in the winter of 1784/1785 Russian Pomors on Spitsbergen harvested 150 polar bears in Magdalenefjorden. In the early 20th century, Norwegian hunters were harvesting 300 bears per year at the same location. Estimates of total historical harvest


title: "Polar bear" content: suggest that from the beginning of the 18th century, roughly 400 to 500 animals were being harvested annually in northern Eurasia, reaching a peak of 1,300 to 1,500 animals in the early 20th century, and falling off as the numbers began dwindling. In the first half of the 20th century, mechanized and overpoweringly efficient methods of hunting and trapping came into use in North America as well. Polar bears were chased from snowmobiles, icebreakers, and airplanes, the latter practice described in a 1965 "New York Times" editorial as being "about as sporting as machine gunning a cow." Norwegians used "self-killing


title: "Polar bear" content: guns", comprising a loaded rifle in a baited box that was placed at the level of a bear's head, and which fired when the string attached to the bait was pulled. The numbers taken grew rapidly in the 1960s, peaking around 1968 with a global total of 1,250 bears that year. Concerns over the future survival of the species led to the development of national regulations on polar bear hunting, beginning in the mid-1950s. The Soviet Union banned all hunting in 1956. Canada began imposing hunting quotas in 1968. Norway passed a series of increasingly strict regulations from 1965 to


title: "Polar bear" content: 1973, and has completely banned hunting since then. The United States began regulating hunting in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973, the International Agreement on the Conservation of Polar Bears was signed by all five nations whose territory is inhabited by polar bears: Canada, Denmark, Norway, the Soviet Union, and the United States. Member countries agreed to place restrictions on recreational and commercial hunting, ban hunting from aircraft and icebreakers, and conduct further research. The treaty allows hunting "by local people using traditional methods". Norway is the only country of the five in which


title: "Polar bear" content: all harvest of polar bears is banned. The agreement was a rare case of international cooperation during the Cold War. Biologist Ian Stirling commented, "For many years, the conservation of polar bears was the only subject in the entire Arctic that nations from both sides of the Iron Curtain could agree upon sufficiently to sign an agreement. Such was the intensity of human fascination with this magnificent predator, the only marine bear." Agreements have been made between countries to co-manage their shared polar bear subpopulations. After several years of negotiations, Russia and the United States signed an agreement in October


title: "Polar bear" content: 2000 to jointly set quotas for indigenous subsistence hunting in Alaska and Chukotka. The treaty was ratified in October 2007. In September 2015, the polar bear range states agreed upon a "circumpolar action plan" describing their conservation strategy for polar bears. Although the United States government has proposed that polar bears be transferred to Appendix I of CITES, which would ban all international trade in polar bear parts, polar bears currently remain listed under Appendix II. This decision was approved of by members of the IUCN and TRAFFIC, who determined that such an uplisting was unlikely to confer a conservation


title: "Polar bear" content: benefit. Polar bears were designated "Not at Risk" in April 1986 and uplisted to "Special Concern" in April 1991. This status was re-evaluated and confirmed in April 1999, November 2002, and April 2008. Polar bears continue to be listed as a species of special concern in Canada because of their sensitivity to overharvest and because of an expected range contraction caused by loss of Arctic sea ice. More than 600 bears are killed per year by humans across Canada, a rate calculated by scientists to be unsustainable for some areas, notably Baffin Bay. Canada has allowed sport hunters accompanied by


title: "Polar bear" content: local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. The guiding of sport hunters provides meaningful employment and an important source of income for northern communities in which economic opportunities are few. Sport hunting can bring CDN$20,000 to $35,000 per bear into northern communities, which until recently has been mostly from American hunters. The territory of Nunavut accounts for the location 80% of annual kills in Canada. In 2005, the government of Nunavut increased the quota from 400 to 518 bears, despite protests from the IUCN Polar Bear Specialist Group. In two areas


title: "Polar bear" content: where harvest levels have been increased based on increased sightings, science-based studies have indicated declining populations, and a third area is considered data-deficient. While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) Nunavut polar bear biologist, Mitchell Taylor, who was formerly responsible for polar bear conservation in the territory, has insisted that bear numbers are being sustained under current hunting limits. In 2010, the 2005 increase was partially reversed. Government of Nunavut officials announced that the


title: "Polar bear" content: polar bear quota for the Baffin Bay region would be gradually reduced from 105 per year to 65 by the year 2013. The Government of the Northwest Territories maintain their own quota of 72 to 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Environment Canada also banned the export from Canada of fur, claws, skulls and other products from polar bears harvested in Baffin Bay as of 1 January 2010. Because of the way polar bear hunting quotas are managed in Canada, attempts to discourage sport hunting would actually increase the number of


title: "Polar bear" content: bears killed in the short term. Canada allocates a certain number of permits each year to sport and subsistence hunting, and those that are not used for sport hunting are re-allocated to indigenous subsistence hunting. Whereas northern communities kill all the polar bears they are permitted to take each year, only half of sport hunters with permits actually manage to kill a polar bear. If a sport hunter does not kill a polar bear before his or her permit expires, the permit cannot be transferred to another hunter. In August 2011, Environment Canada published a national polar bear conservation strategy.


title: "Polar bear" content: In Greenland, hunting restrictions were first introduced in 1994 and expanded by executive order in 2005. Until 2005 Greenland placed no limit on hunting by indigenous people. However, in 2006 it imposed a limit of 150, while also allowed recreational hunting for the first time. Other provisions included year-round protection of cubs and mothers, restrictions on weapons used and various administrative requirements to catalogue kills. Polar bear were hunted heavily in Svalbard, Norway throughout the 19th century and to as recently as 1973, when the conservation treaty was signed. 900 bears a year were harvested in the 1920s and after


title: "Polar bear" content: World War II, there were as many as 400–500 harvested annually. Some regulations of hunting did exist. In 1927, poisoning was outlawed while in 1939, certain denning sights were declared off limits. The killing of females and cubs was made illegal in 1965. Killing of polar bears decreased somewhat 25–30 years before the treaty. Despite this, the polar bear population continued to decline and by 1973, only around 1000 bears were left in Svalbard. Only with the passage of the treaty did they begin to recover. The Soviet Union banned the harvest of polar bears in 1956; however, poaching continued


title: "Polar bear" content: and is estimated to pose a serious threat to the polar bear population. In recent years, polar bears have approached coastal villages in Chukotka more frequently due to the shrinking of the sea ice, endangering humans and raising concerns that illegal hunting would become even more prevalent. In 2007, the Russian government made subsistence hunting legal for indigenous Chukotkan peoples only, a move supported by Russia's most prominent bear researchers and the World Wide Fund for Nature as a means to curb poaching. Polar bears are currently listed as "Rare", of "Uncertain Status", or "Rehabilitated and rehabilitating" in the Red


title: "Polar bear" content: Data Book of Russia, depending on population. In 2010, the Ministry of Natural Resources and Environment published a strategy for polar bear conservation in Russia. The Marine Mammal Protection Act of 1972 afforded polar bears some protection in the United States. It banned hunting (except by indigenous subsistence hunters), banned importing of polar bear parts (except polar bear pelts taken legally in Canada), and banned the harassment of polar bears. On 15 May 2008, the United States Department of the Interior listed the polar bear as a threatened species under the Endangered Species Act, citing the melting of Arctic sea


title: "Polar bear" content: ice as the primary threat to the polar bear. It banned all importing of polar bear trophies. Importing products made from polar bears had been prohibited from 1972 to 1994 under the Marine Mammal Protection Act, and restricted between 1994 and 2008. Under those restrictions, permits from the United States Fish and Wildlife Service were required to import sport-hunted polar bear trophies taken in hunting expeditions in Canada. The permit process required that the bear be taken from an area with quotas based on sound management principles. Since 1994, hundreds of sport-hunted polar bear trophies have been imported into the


title: "Polar bear" content: U.S. In 2015, the U.S. Fish and Wildlife Service published a draft conservation management plan for polar bears to improve their status under the Endangered Species Act and the Marine Mammal Protection Act. Polar bear population sizes and trends are difficult to estimate accurately because they occupy remote home ranges and exist at low population densities. Polar bear fieldwork can also be hazardous to researchers. As of 2015, the International Union for Conservation of Nature (IUCN) reports that the global population of polar bears is 22,000 to 31,000, and the current population trend is unknown. Nevertheless, polar bears are listed


title: "Polar bear" content: as "Vulnerable" under criterion A3c, which indicates an expected population decrease of ≥30% over the next three generations (~34.5 years) due to "decline in area of occupancy, extent of occurrence and/or quality of habitat". Risks to the polar bear include climate change, pollution in the form of toxic contaminants, conflicts with shipping, oil and gas exploration and development, and human-bear interactions including harvesting and possible stresses from recreational polar-bear watching. According to the World Wildlife Fund, the polar bear is important as an indicator of Arctic ecosystem health. Polar bears are studied to gain understanding of what is happening throughout


title: "Polar bear" content: the Arctic, because at-risk polar bears are often a sign of something wrong with the Arctic marine ecosystem. The International Union for Conservation of Nature, Arctic Climate Impact Assessment, United States Geological Survey and many leading polar bear biologists have expressed grave concerns about the impact of climate change, including the belief that the current warming trend imperils the survival of the polar bear. The key danger posed by climate change is malnutrition or starvation due to habitat loss. Polar bears hunt seals from a platform of sea ice. Rising temperatures cause the sea ice to melt earlier in the


title: "Polar bear" content: year, driving the bears to shore before they have built sufficient fat reserves to survive the period of scarce food in the late summer and early fall. Reduction in sea-ice cover also forces bears to swim longer distances, which further depletes their energy stores and occasionally leads to drowning. Thinner sea ice tends to deform more easily, which appears to make it more difficult for polar bears to access seals. Insufficient nourishment leads to lower reproductive rates in adult females and lower survival rates in cubs and juvenile bears, in addition to poorer body condition in bears of all ages.


title: "Polar bear" content: In addition to creating nutritional stress, a warming climate is expected to affect various other aspects of polar bear life: Changes in sea ice affect the ability of pregnant females to build suitable maternity dens. As the distance increases between the pack ice and the coast, females must swim longer distances to reach favored denning areas on land. Thawing of permafrost would affect the bears who traditionally den underground, and warm winters could result in den roofs collapsing or having reduced insulative value. For the polar bears that currently den on multi-year ice, increased ice mobility may result in longer


title: "Polar bear" content: distances for mothers and young cubs to walk when they return to seal-hunting areas in the spring. Disease-causing bacteria and parasites would flourish more readily in a warmer climate. Problematic interactions between polar bears and humans, such as foraging by bears in garbage dumps, have historically been more prevalent in years when ice-floe breakup occurred early and local polar bears were relatively thin. Increased human-bear interactions, including fatal attacks on humans, are likely to increase as the sea ice shrinks and hungry bears try to find food on land. The effects of climate change are most profound in the southern


title: "Polar bear" content: part of the polar bear's range, and this is indeed where significant degradation of local populations has been observed. The Western Hudson Bay subpopulation, in a southern part of the range, also happens to be one of the best-studied polar bear subpopulations. This subpopulation feeds heavily on ringed seals in late spring, when newly weaned and easily hunted seal pups are abundant. The late spring hunting season ends for polar bears when the ice begins to melt and break up, and they fast or eat little during the summer until the sea freezes again. Due to warming air temperatures, ice-floe


title: "Polar bear" content: breakup in western Hudson Bay is currently occurring three weeks earlier than it did 30 years ago, reducing the duration of the polar bear feeding season. The body condition of polar bears has declined during this period; the average weight of lone (and likely pregnant) female polar bears was approximately in 1980 and in 2004. Between 1987 and 2004, the Western Hudson Bay population declined by 22%, although the population is currently listed as "stable". As the climate change melts sea ice, the U.S. Geological Survey projects that two-thirds of polar bears will disappear by 2050. In Alaska, the effects


title: "Polar bear" content: of sea ice shrinkage have contributed to higher mortality rates in polar bear cubs, and have led to changes in the denning locations of pregnant females. In recent years, polar bears in the Arctic have undertaken longer than usual swims to find prey, possibly resulting in four recorded drownings in the unusually large ice pack regression of 2005. A new development is that polar bears have begun ranging to new territory. While not unheard of but still uncommon, polar bears have been sighted increasingly in larger numbers ashore, staying on the mainland for longer periods of time during the summer


title: "Polar bear" content: months, particularly in North Canada, traveling farther inland. This may cause an increased reliance on terrestrial diets, such as goose eggs, waterfowl and caribou, as well as increased human–bear conflict. Polar bears accumulate high levels of persistent organic pollutants such as polychlorinated biphenyl (PCBs) and chlorinated pesticides. Due to their position at the top of the ecological pyramid, with a diet heavy in blubber in which halocarbons concentrate, their bodies are among the most contaminated of Arctic mammals. Halocarbons are known to be toxic to other animals, because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol


title: "Polar bear" content: suggest similar effects on polar bears. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. Many chemicals, such as PCBs and DDT, have been internationally banned due to the recognition of their harm on the environment. Their concentrations in polar bear tissues continued to rise for decades after being banned as these chemicals spread through the food chain. Since then, the trend seems to have discontinued, with tissue concentrations of PCBs declining between studies performed from 1989 to 1993 and studies performed from 1996 to 2002. During the same time periods,


title: "Polar bear" content: DDT was notably lower in the Western Hudson Bay population only. Oil and gas development in polar bear habitat can affect the bears in a variety of ways. An oil spill in the Arctic would most likely concentrate in the areas where polar bears and their prey are also concentrated, such as sea ice leads. Because polar bears rely partly on their fur for insulation and soiling of the fur by oil reduces its insulative value, oil spills put bears at risk of dying from hypothermia. Polar bears exposed to oil spill conditions have been observed to lick the oil


title: "Polar bear" content: from their fur, leading to fatal kidney failure. Maternity dens, used by pregnant females and by females with infants, can also be disturbed by nearby oil exploration and development. Disturbance of these sensitive sites may trigger the mother to abandon her den prematurely, or abandon her litter altogether. Steven Amstrup and other U.S. Geological Survey scientists have predicted two-thirds of the world's polar bears may disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by climate change, though the validity of this study has been debated. The bears could disappear from Europe, Asia, and


title: "Polar bear" content: Alaska, and be depleted from the Canadian Arctic Archipelago and areas off the northern Greenland coast. By 2080, they could disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic Archipelago. However, in the short term, some polar bear populations in historically colder regions of the Arctic may temporarily benefit from a milder climate, as multiyear ice that is too thick for seals to create breathing holes is replaced by thinner annual ice. Polar bears diverged from brown bears 400,000–600,000 years ago and have survived past periods of climate fluctuation. It has


title: "Polar bear" content: been claimed that polar bears will be able to adapt to terrestrial food sources as the sea ice they use to hunt seals disappears. However, most polar bear biologists think that polar bears will be unable to completely offset the loss of calorie-rich seal blubber with terrestrial foods, and that they will be outcompeted by brown bears in this terrestrial niche, ultimately leading to a population decline. Warnings about the future of the polar bear are often contrasted with the fact that worldwide population estimates have increased over the past 50 years and are relatively stable today. Some estimates of


title: "Polar bear" content: the global population are around 5,000 to 10,000 in the early 1970s; other estimates were 20,000 to 40,000 during the 1980s. Current estimates put the global population at between 20,000 and 25,000 or 22,000 and 31,000. There are several reasons for the apparent discordance between past and projected population trends: estimates from the 1950s and 1960s were based on stories from explorers and hunters rather than on scientific surveys. Second, controls of harvesting were introduced that allowed this previously overhunted species to recover. Third, the recent effects of climate change have affected sea ice abundance in different areas to varying


title: "Polar bear" content: degrees. Debate over the listing of the polar bear under endangered species legislation has put conservation groups and Canada's Inuit at opposing positions; the Nunavut government and many northern residents have condemned the U.S. initiative to list the polar bear under the Endangered Species Act. Many Inuit believe the polar bear population is increasing, and restrictions on commercial sport-hunting are likely to lead to a loss of income to their communities. For the indigenous peoples of the Arctic, polar bears have long played an important cultural and material role. Polar bear remains have been found at hunting sites dating to


title: "Polar bear" content: 2,500 to 3,000 years ago and 1,500-year-old cave paintings of polar bears have been found in the Chukchi Peninsula. Indeed, it has been suggested that Arctic peoples' skills in seal hunting and igloo construction has been in part acquired from the polar bears themselves. The Inuit and Alaska Natives have many folk tales featuring the bears including legends in which bears are humans when inside their own houses and put on bear hides when going outside, and stories of how the constellation that is said to resemble a great bear surrounded by dogs came into being. These legends reveal a


title: "Polar bear" content: deep respect for the polar bear, which is portrayed as both spiritually powerful and closely akin to humans. The human-like posture of bears when standing and sitting, and the resemblance of a skinned bear carcass to the human body, have probably contributed to the belief that the spirits of humans and bears were interchangeable. Among the Chukchi and Yupik of eastern Siberia, there was a longstanding shamanistic ritual of "thanksgiving" to the hunted polar bear. After killing the animal, its head and skin were removed and cleaned and brought into the home, and a feast was held in the hunting


title: "Polar bear" content: camp in its honor. To appease the spirit of the bear, traditional song and drum music was played, and the skull was ceremonially fed and offered a pipe. Only once the spirit was appeased was the skull be separated from the skin, taken beyond the bounds of the homestead, and placed in the ground, facing north. The Nenets of north-central Siberia placed particular value on the talismanic power of the prominent canine teeth. These were traded in the villages of the lower Yenisei and Khatanga rivers to the forest-dwelling peoples further south, who would sew them into their hats as


title: "Polar bear" content: protection against brown bears. It was believed that the "little nephew" (the brown bear) would not dare to attack a man wearing the tooth of its powerful "big uncle", the polar bear. The skulls of killed polar bears were buried at sacred sites, and altars, called "sedyangi", were constructed out of the skulls. Several such sites have been preserved on the Yamal Peninsula. Their distinctive appearance and their association with the Arctic have made polar bears popular icons, especially in those areas where they are native. The Canadian two-dollar coin carries an image of a lone polar bear on its


title: "Polar bear" content: reverse side, while a special millennium edition featured three. Vehicle license plates in the Northwest Territories and Nunavut in Canada are in the shape of a polar bear. The polar bear is the mascot of Bowdoin College, Maine, the University of Alaska Fairbanks, and the 1988 Winter Olympics held in Calgary. The Eisbären Berlin hockey team uses a roaring polar bear as their logo, and the Charlotte, North Carolina hockey team the Charlotte Checkers uses a polar bear named Chubby Checker as their mascot. Companies such as Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum, and Good Humor-Breyers have used images of


title: "Polar bear" content: the polar bear in advertising, while Fox's Glacier Mints have featured a polar bear named Peppy as the brand mascot since 1922. Polar bears are popular in fiction, particularly in books for children or teenagers. For example, "The Polar Bear Son" is adapted from a traditional Inuit tale. The animated television series "Noah's Island" features a polar bear named Noah as the protagonist. Polar bears feature prominently in "East" (also released as "North Child") by Edith Pattou, "The Bear" by Raymond Briggs (adapted into an animated short in 1998), and Chris d'Lacey's "The Fire Within" series. The "panserbjørne" of Philip


title: "Polar bear" content: Pullman's fantasy trilogy "His Dark Materials" are sapient, dignified polar bears who exhibit anthropomorphic qualities, and feature prominently in the 2007 film adaptation of "The Golden Compass". The television series "Lost" features polar bears living on the tropical island setting. Polar bear The polar bear ("Ursus maritimus") is a hypercarnivorous bear whose native range lies largely within the Arctic Circle, encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is a large bear, approximately the same size as the omnivorous Kodiak bear ("Ursus arctos middendorffi"). A boar (adult male) weighs around , while a sow (adult female)


title: "Pope Innocent III" content: the French crown and diminishing the distinct regional culture and high level of influence of the Counts of Barcelona. Under the leadership of Simon de Montfort, 5th Earl of Leicester, a campaign was launched. The Albigensian Crusade, which led to the slaughter of approximately 20,000 men, women and children, Cathar and Catholic alike and brought the region firmly under the control of the king of France. It was directed not only against heretical Christians, but also the nobility of Toulouse and vassals of the Crown of Aragon. King Peter II of Aragon was directly involved in the conflict, and was


title: Phonograph content: Phonograph The phonograph is a device for the mechanical recording and reproduction of sound. In its later forms, it is also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910) or, since the 1940s, a record player. The sound vibration waveforms are recorded as corresponding physical deviations of a spiral groove engraved, etched, incised, or impressed into the surface of a rotating cylinder or disc, called a "record". To recreate the sound, the surface is similarly rotated while a playback stylus traces the groove and is therefore vibrated by it, very faintly


title: Phonograph content: reproducing the recorded sound. In early acoustic phonographs, the stylus vibrated a diaphragm which produced sound waves which were coupled to the open air through a flaring horn, or directly to the listener's ears through stethoscope-type earphones. The phonograph was invented in 1877 by Thomas Edison. While other inventors had produced devices that could record sounds, Edison's phonograph was the first to be able to reproduce the recorded sound. His phonograph originally recorded sound onto a tinfoil sheet wrapped around a rotating cylinder. A stylus responding to sound vibrations produced an up and down or hill-and-dale groove in the foil.


title: Phonograph content: Alexander Graham Bell's Volta Laboratory made several improvements in the 1880s and introduced the "graphophone", including the use of wax-coated cardboard cylinders and a cutting stylus that moved from side to side in a zigzag groove around the record. In the 1890s, Emile Berliner initiated the transition from phonograph cylinders to flat discs with a spiral groove running from the periphery to near the center, coining the term "gramophone" for disc record players, which is predominantly used in many languages. Later improvements through the years included modifications to the turntable and its drive system, the stylus or needle, and the


title: Phonograph content: sound and equalization systems. The disc phonograph record was the dominant audio recording format throughout most of the 20th century. From the mid-1980s on, phonograph use on a standard record player declined sharply because of the rise of the cassette tape, compact disc and other digital recording formats. Records are still a favorite format for some audiophiles, DJs and turntablists (particularly in hip hop and electronic dance music), and have undergone a revival in the 2010s. The original recordings of musicians, which may have been recorded on tape or digital methods, are sometimes re-issued on vinyl. Usage of terminology is


title: Phonograph content: not uniform across the English-speaking world (see below). In more modern usage, the playback device is often called a "turntable", "record player", or "record changer". When used in conjunction with a mixer as part of a DJ setup, turntables are often colloquially called "decks". In later electric phonographs (more often known since the 1940s as record players or, most recently, turntables), the motions of the stylus are converted into an analogous electrical signal by a transducer, then converted back into sound by a loudspeaker. The term "phonograph" ("sound writing") was derived from the Greek words ("phonē", "sound" or "voice") and


title: Phonograph content: ("graphē", "writing"). The similar related terms "gramophone" (from the Greek γράμμα "gramma" "letter" and φωνή "phōnē" "voice") and "graphophone" have similar root meanings. The roots were already familiar from existing 19th-century words such as "photograph" ("light writing"), "telegraph" ("distant writing"), and "telephone" ("distant sound"). The new term may have been influenced by the existing words "phonographic" and "phonography", which referred to a system of phonetic shorthand; in 1852 "The New York Times" carried an advertisement for "Professor Webster's phonographic class", and in 1859 the New York State Teachers Association tabled a motion to "employ a phonographic recorder" to record its


title: Phonograph content: meetings. Arguably, any device used to record sound or reproduce recorded sound could be called a type of "phonograph", but in common practice the word has come to mean historic technologies of sound recording, involving audio-frequency modulations of a physical trace or groove. In the late-19th and early-20th centuries, "Phonograph", "Gramophone", "Graphophone", "Zonophone", "Graphonole" and the like were still brand names specific to various makers of sometimes very different (i.e. cylinder and disc) machines; so considerable use was made of the generic term "talking machine", especially in print. "Talking machine" had earlier been used to refer to complicated devices which


title: Phonograph content: produced a crude imitation of speech, by simulating the workings of the vocal cords, tongue, and lips – a potential source of confusion both then and now. In British English, "gramophone" may refer to any sound-reproducing machine using disc records, which were introduced and popularized in the UK by the Gramophone Company. Originally, "gramophone" was a proprietary trademark of that company and any use of the name by competing makers of disc records was vigorously prosecuted in the courts, but in 1910 an English court decision decreed that it had become a generic term; it has been so used in


title: Phonograph content: the UK and most Commonwealth countries ever since. The term "phonograph" was usually restricted to machines that used cylinder records. "Gramophone" generally referred to a wind-up machine. After the introduction of the softer vinyl records, -rpm LPs (long-playing records) and 45-rpm "single" or two-song records, and EPs (extended-play recordings), the common name became "record player" or "turntable". Often the home record player was part of a system that included a radio ("radiogram") and, later, might also play audiotape cassettes. From about 1960, such a system began to be described as a "hi-fi" (high-fidelity, monophonic) or a "stereo" (most systems being


title: Phonograph content: stereophonic by the mid-1960s). In American English, "phonograph", properly specific to machines made by Edison, was sometimes used in a generic sense as early as the 1890s to include cylinder-playing machines made by others. But it was then considered strictly incorrect to apply it to Emile Berliner's upstart Gramophone, a very different machine which played discs. "Talking machine" was the comprehensive generic term, but in the early 20th century the general public was increasingly applying the word "phonograph" indiscriminately to both cylinder and disc machines and to the records they played. By the time of the First World War, the


title: Phonograph content: mass advertising and popularity of the Victor Talking Machine Company's Victrolas (a line of disc-playing machines characterized by their concealed horns) was leading to widespread generic use of the word "victrola" for any machine that played discs, which were however still called "phonograph records" or simply "records", almost never "victrola records". After electrical disc-playing machines started appearing on the market during the second half of the 1920s, usually sharing the same cabinet with a radio receiver, the term "record player" was increasingly favored by users when referring to the device. Manufacturers, however, typically advertised such combinations as "radio-phonographs". Portable record


title: Phonograph content: players (no radio included), with a latched cover and an integrated power amplifier and loudspeaker, were fairly common as well, especially in schools and for use by children and teenagers. In the years following the Second World War, as "hi-fi" (high-fidelity, monophonic) and, later, "stereo" (stereophonic) component sound systems slowly evolved from an exotic specialty item into a common feature of American homes, the description of the record-spinning component as a "record changer" (which could automatically play through a stacked series of discs) or a "turntable" (which could hold only one disc at a time) entered common usage. By about


title: Phonograph content: 1980 the use of a "record changer", which might damage the stacked discs, was widely disparaged. So, the "turntable" emerged triumphant and retained its position to the end of the 20th century and beyond. Through all these changes, however, the discs have continued to be known as "phonograph records" or, much more commonly, simply as "records". The brand name "Gramophone" was not used in the USA after 1901, and the word fell out of use there, although it has survived in its nickname form, "Grammy", as the name of the Grammy Awards. The Grammy trophy itself is a small rendering


title: Phonograph content: of a gramophone, resembling a Victor disc machine with a taper arm. Modern amplifier-component manufacturers continue to label the input jack which accepts the output from a modern magnetic pickup cartridge as the "phono" input, abbreviated from "phonograph". In Australian English, "record player" was the term; "turntable" was a more technical term; "gramophone" was restricted to the old mechanical (i.e., wind-up) players; and "phonograph" was used as in British English. Several inventors devised machines to record sound prior to Thomas Edison's phonograph, Edison being the first to invent a device that could both record and reproduce sound. The phonograph's predecessors


title: Phonograph content: include Édouard-Léon Scott de Martinville's phonautograph, and Charles Cros's paleophone. Recordings made with the phonautograph were intended to be visual representations of the sound, but were never sonically reproduced until 2008. Cros's paleophone was intended to both record and reproduce sound but had not been developed beyond a basic concept at the time of Edison's successful demonstration of the Phonograph in 1877. Direct tracings of the vibrations of sound-producing objects such as tuning forks had been made by English physician Thomas Young in 1807, but the first known device for recording airborne speech, music and other sounds is the phonautograph,


title: Phonograph content: patented in 1857 by French typesetter and inventor Édouard-Léon Scott de Martinville. In this device, sound waves travelling through the air vibrated a parchment diaphragm which was linked to a bristle, and the bristle traced a line through a thin coating of soot on a sheet of paper wrapped around a rotating cylinder. The sound vibrations were recorded as undulations or other irregularities in the traced line. Scott's phonautograph was intended purely for the visual study and analysis of the tracings. Reproduction of the recorded sound was not possible with the original phonautograph. In 2008, phonautograph recordings made by Scott


title: Phonograph content: were played back as sound by American audio historians, who used optical scanning and computer processing to convert the traced waveforms into digital audio files. These recordings, made circa 1860, include fragments of two French songs and a recitation in Italian. Charles Cros, a French poet and amateur scientist, is the first person known to have made the conceptual leap from recording sound as a traced line to the theoretical possibility of reproducing the sound from the tracing and then to devising a definite method for accomplishing the reproduction. On April 30, 1877, he deposited a sealed envelope containing a


title: Phonograph content: summary of his ideas with the French Academy of Sciences, a standard procedure used by scientists and inventors to establish priority of conception of unpublished ideas in the event of any later dispute. Cros proposed the use of photoengraving, a process already in use to make metal printing plates from line drawings, to convert an insubstantial phonautograph tracing in soot into a groove or ridge on a metal disc or cylinder. This metal surface would then be given the same motion and speed as the original recording surface. A stylus linked to a diaphragm would be made to ride in


title: Phonograph content: the groove or on the ridge so that the stylus would be moved back and forth in accordance with the recorded vibrations. It would transmit these vibrations to the connected diaphragm, and the diaphragm would transmit them to the air, reproducing the original sound. An account of his invention was published on October 10, 1877, by which date Cros had devised a more direct procedure: the recording stylus could scribe its tracing through a thin coating of acid-resistant material on a metal surface and the surface could then be etched in an acid bath, producing the desired groove without the


title: Phonograph content: complication of an intermediate photographic procedure. The author of this article called the device a "phonographe", but Cros himself favored the word "paleophone", sometimes rendered in French as "voix du passé" (voice of the past) but more literally meaning "ancient sound", which accorded well with his vision of his invention's potential for creating an archive of sound recordings that would be available to listeners in the distant future. Cros was a poet of meager means, not in a position to pay a machinist to build a working model, and largely content to bequeath his ideas to the public domain free


title: Phonograph content: of charge and let others reduce them to practice, but after the earliest reports of Edison's presumably independent invention crossed the Atlantic he had his sealed letter of April 30 opened and read at the December 3, 1877 meeting of the French Academy of Sciences, claiming due scientific credit for priority of conception. Throughout the first decade (1890–1900) of commercial production of the earliest crude disc records, the direct acid-etch method first invented by Cros was used to create the metal master discs, but Cros was not around to claim any credit or to witness the humble beginnings of the


title: Phonograph content: eventually rich phonographic library he had foreseen. He had died in 1888 at the age of 45. Thomas Alva Edison conceived the principle of recording and reproducing sound between May and July 1877 as a byproduct of his efforts to "play back" recorded telegraph messages and to automate speech sounds for transmission by telephone. He announced his invention of the first "phonograph", a device for recording and replaying sound, on November 21, 1877 (early reports appear in Scientific American and several newspapers in the beginning of November, and an even earlier announcement of Edison working on a 'talking-machine' can be


title: Phonograph content: found in the Chicago Daily Tribune on May 9), and he demonstrated the device for the first time on November 29 (it was patented on February 19, 1878 as US Patent 200,521). "In December, 1877, a young man came into the office of the SCIENTIFIC AMERICAN, and placed before the editors a small, simple machine about which very few preliminary remarks were offered. The visitor without any ceremony whatever turned the crank, and to the astonishment of all present the machine said: "Good morning. How do you do? How do you like the phonograph?" The machine thus spoke for itself,


title: Phonograph content: and made known the fact that it was the phonograph..." Edison presented his own account of inventing the phonograph. "I was experimenting," he said, "on an automatic method of recording telegraph messages on a disk of paper laid on a revolving platen, exactly the same as the disk talking-machine of to-day. The platen had a spiral groove on its surface, like the disk. Over this was placed a circular disk of paper; an electromagnet with the embossing point connected to an arm traveled over the disk; and any signals given through the magnets were embossed on the disk of paper.


title: Phonograph content: If this disc was removed from the machine and put on a similar machine provided with a contact point, the embossed record would cause the signals to be repeated into another wire. The ordinary speed of telegraphic signals is thirty-five to forty words a minute; but with this machine several hundred words were possible." "From my experiments on the telephone I knew of how to work a pawl connected to the diaphragm; and this engaging a ratchet-wheel served to give continuous rotation to a pulley. This pulley was connected by a cord to a little paper toy representing a man


title: Phonograph content: sawing wood. Hence, if one shouted: ' Mary had a little lamb,' etc., the paper man would start sawing wood. I reached the conclusion that if I could record the movements of the diaphragm properly, I could cause such records to reproduce the original movements imparted to the diaphragm by the voice, and thus succeed in recording and reproducing the human voice." "Instead of using a disk I designed a little machine using a cylinder provided with grooves around the surface. Over this was to be placed tinfoil, which easily received and recorded the movements of the diaphragm. A sketch


title: Phonograph content: was made, and the piece-work price, $18, was marked on the sketch. I was in the habit of marking the price I would pay on each sketch. If the workman lost, I would pay his regular wages; if he made more than the wages, he kept it. The workman who got the sketch was John Kruesi. I didn't have much faith that it would work, expecting that I might possibly hear a word or so that would give hope of a future for the idea. Kruesi, when he had nearly finished it, asked what it was for. I told him


title: Phonograph content: I was going to record talking, and then have the machine talk back. He thought it absurd. However, it was finished, the foil was put on; I then shouted 'Mary had a little lamb', etc. I adjusted the reproducer, and the machine reproduced it perfectly. I was never so taken aback in my life. Everybody was astonished. I was always afraid of things that worked the first time. Long experience proved that there were great drawbacks found generally before they could be got commercial; but here was something there was no doubt of." The music critic Herman Klein attended an


title: Phonograph content: early demonstration (1881–2) of a similar machine. On the early phonograph's reproductive capabilities he writes "It sounded to my ear like someone singing about half a mile away, or talking at the other end of a big hall; but the effect was rather pleasant, save for a peculiar nasal quality wholly due to the mechanism, though there was little of the scratching which later was a prominent feature of the flat disc. Recording for that primitive machine was a comparatively simple matter. I had to keep my mouth about six inches away from the horn and remember not to make


title: Phonograph content: my voice too loud if I wanted anything approximating to a clear reproduction; that was all. When it was played over to me and I heard my own voice for the first time, one or two friends who were present said that it sounded rather like mine; others declared that they would never have recognised it. I daresay both opinions were correct." Edison's early phonographs recorded onto a thin sheet of metal, normally tinfoil, which was temporarily wrapped around a helically grooved cylinder mounted on a correspondingly threaded rod supported by plain and threaded bearings. While the cylinder was rotated


title: Phonograph content: and slowly progressed along its axis, the airborne sound vibrated a diaphragm connected to a stylus that indented the foil into the cylinder's groove, thereby recording the vibrations as "hill-and-dale" variations of the depth of the indentation. Playback was accomplished by exactly repeating the recording procedure, the only difference being that the recorded foil now served to vibrate the stylus, which transmitted its vibrations to the diaphragm and onward into the air as audible sound. Although Edison's very first experimental tinfoil phonograph used separate and somewhat different recording and playback assemblies, in subsequent machines a single diaphragm and stylus served


title: Phonograph content: both purposes. One peculiar consequence was that it was possible to overdub additional sound onto a recording being played back. The recording was heavily worn by each playing, and it was nearly impossible to accurately remount a recorded foil after it had been removed from the cylinder. In this form, the only practical use that could be found for the phonograph was as a startling novelty for private amusement at home or public exhibitions for profit. Edison's early patents show that he was aware that sound could be recorded as a spiral on a disc, but Edison concentrated his efforts


title: Phonograph content: on cylinders, since the groove on the outside of a rotating cylinder provides a constant velocity to the stylus in the groove, which Edison considered more "scientifically correct". Edison's patent specified that the audio recording be embossed, and it was not until 1886 that vertically modulated engraved recording using wax-coated cylinders was patented by Chichester Bell and Charles Sumner Tainter. They named their version the Graphophone. The use of a flat recording surface instead of a cylindrical one was an obvious alternative which thought-experimenter Charles Cros initially favored and which practical experimenter Thomas Edison and others actually tested in the


title: Phonograph content: late 1870s and early 1880s. The oldest surviving example is a copper electrotype of a recording cut into a wax disc in 1881. The commercialization of sound recording technology was initially aimed at use for business correspondence and transcription into writing, in which the cylindrical form offered certain advantages, the storage of large numbers of records seemed unlikely, and the ease of producing multiple copies was not a consideration. In 1887, Emile Berliner patented a variant of the phonograph which he named the Gramophone. Berliner's approach was essentially the same one proposed, but never implemented, by Charles Cros in 1877.


title: Phonograph content: The diaphragm was linked to the recording stylus in a way that caused it to vibrate laterally (side to side) as it traced a spiral onto a zinc disc very thinly coated with a compound of beeswax. The zinc disc was then immersed in a bath of chromic acid; this etched a groove into the disc where the stylus had removed the coating, after which the recording could be played. With some later improvements the flat discs of Berliner could be produced in large quantities at much lower cost than the cylinders of Edison's system. In May 1889, in San


title: Phonograph content: Francisco, the first "phonograph parlor" opened. It featured a row of coin-operated machines, each supplied with a different wax cylinder record. The customer selected a machine according to the title that it advertised, inserted a nickel, then heard the recording through stethoscope-like listening tubes. By the mid-1890s, most American cities had at least one phonograph parlor. The coin-operated mechanism was invented by Louis T. Glass and William S. Arnold. The cabinet contained an Edison Class M or Class E phonograph. The Class M was powered by a wet-cell glass battery that would spill dangerous acid if it tipped over or


title: Phonograph content: broke. The Class E sold for a lower price and ran on 120V DC. The phenomenon of phonograph parlors peaked in Paris around 1900: in Pathé's luxurious salon, patrons sat in plush upholstered chairs and chose from among many hundreds of available cylinders by using speaking tubes to communicate with attendants on the floor below. By 1890, record manufacturers had begun using a rudimentary duplication process to mass-produce their product. While the live performers recorded the master phonograph, up to ten tubes led to blank cylinders in other phonographs. Until this development, each record had to be custom-made. Before long,


title: Phonograph content: a more advanced pantograph-based process made it possible to simultaneously produce 90–150 copies of each record. However, as demand for certain records grew, popular artists still needed to re-record and re-re-record their songs. Reportedly, the medium's first major African-American star George Washington Johnson was obliged to perform his "The Laughing Song" (or the separate "The Whistling Coon") literally thousands of times in a studio during his recording career. Sometimes he would sing "The Laughing Song" more than fifty times in a day, at twenty cents per rendition. (The average price of a single cylinder in the mid-1890s was about fifty


title: Phonograph content: cents.) Frank Lambert's lead cylinder recording for an experimental talking clock is often identified as the oldest surviving playable sound recording, although the evidence advanced for its early date is controversial. Wax phonograph cylinder recordings of Handel's choral music made on June 29, 1888, at The Crystal Palace in London were thought to be the oldest-known surviving musical recordings, until the recent playback by a group of American historians of a phonautograph recording of "Au clair de la lune" made on April 9, 1860. The 1860 phonautogram had not until then been played, as it was only a transcription of


title: Phonograph content: sound waves into graphic form on paper for visual study. Recently developed optical scanning and image processing techniques have given new life to early recordings by making it possible to play unusually delicate or physically unplayable media without physical contact. A recording made on a sheet of tinfoil at an 1878 demonstration of Edison's phonograph in St. Louis, Missouri has been played back by optical scanning and digital analysis. A few other early tinfoil recordings are known to survive, including a slightly earlier one which is believed to preserve the voice of U.S. President Rutherford B. Hayes, but as of


title: Phonograph content: May 2014 they have not yet been scanned. These antique tinfoil recordings, which have typically been stored folded, are too fragile to be played back with a stylus without seriously damaging them. Edison's 1877 tinfoil recording of "Mary Had a Little Lamb", not preserved, has been called the first instance of recorded verse. On the occasion of the 50th anniversary of the phonograph, Edison recounted reciting "Mary Had a Little Lamb" to test his first machine. The 1927 event was filmed by an early sound-on-film newsreel camera, and an audio clip from that film's soundtrack is sometimes mistakenly presented as


title: Phonograph content: the original 1877 recording. Wax cylinder recordings made by 19th century media legends such as P. T. Barnum and Shakespearean actor Edwin Booth are amongst the earliest verified recordings by the famous that have survived to the present. Alexander Graham Bell and his two associates took Edison's tinfoil phonograph and modified it considerably to make it reproduce sound from wax instead of tinfoil. They began their work at Bell's Volta Laboratory in Washington, D. C., in 1879, and continued until they were granted basic patents in 1886 for recording in wax. Although Edison had invented the phonograph in 1877 the


title: Phonograph content: fame bestowed on him for this invention was not due to its efficiency. Recording with his tinfoil phonograph was too difficult to be practical, as the tinfoil tore easily, and even when the stylus was properly adjusted, its reproduction of sound was distorted, and good for only a few playbacks; nevertheless Edison had hit upon the secret of sound recording. However immediately after his discovery he did not improve it, allegedly because of an agreement to spend the next five years developing the New York City electric light and power system. Meanwhile, Bell, a scientist and experimenter at heart, was


title: Phonograph content: looking for new worlds to conquer after his invention of the telephone. According to Sumner Tainter, it was through Gardiner Green Hubbard that Bell took up the phonograph challenge. Bell had married Hubbard's daughter Mabel in 1879 while Hubbard was president of the Edison Speaking Phonograph Co., and his organization, which had purchased the Edison patent, was financially troubled because people did not want to buy a machine which seldom worked well and proved difficult for the average person to operate. In 1879 Hubbard got Bell interested in improving the phonograph, and it was agreed that a laboratory should be


title: Phonograph content: set up in Washington. Experiments were also to be conducted on the transmission of sound by light, which resulted in the selenium-celled Photophone. By 1881, the Volta associates had succeeded in improving an Edison tinfoil machine to some extent. Wax was put in the grooves of the heavy iron cylinder, and no tinfoil was used. Rather than apply for a patent at that time, however, they deposited the machine in a sealed box at the Smithsonian, and specified that it was not to be opened without the consent of two of the three men. The sound vibrations had been indented