The start of travel appears to be triggered by decreasing day lengths; emperor penguins in captivity have been induced successfully into breeding by using lighting systems mimicking seasonal Antarctic day lengths.
The penguins start courtship in March or April, when the temperature can be as low as −40 °C (−40 °F). SONY Vaio VPC-EB3E1R/BQ CPU Fan A lone male gives an ecstatic display, where it stands still and places its head on its chest before inhaling and giving a courtship call for 1–2 seconds; it then moves around the colony and repeats the call. A male and female then stand face to face, with one extending its head and neck up and the other mirroring it; they both hold this posture for several minutes. Dell Precision M4500 CPU FanOnce in pairs, couples waddle around the colony together, with the female usually following the male. Before copulation, one bird bows deeply to its mate, its bill pointed close to the ground, and its mate then does the same.[64]
Emperor penguins are serially monogamous. They have only one mate each year, and stay faithful to that mate. However, fidelity between years is only about 15%.[64HP G71-340US CPU Fan] The narrow window of opportunity available for mating appears to be an influence, as there is a priority to mate and breed which often precludes waiting for the appearance of the previous year's partner.
The female penguin lays one 460–470 g (1 lb) egg in May or early June;[64] it is vaguely pear-shaped, pale greenish-white, and measures around 12 × 8 cm (4¾ x 3 in).[6Toshiba Satellite L675D-S7016 CPU Fan2] It represents just 2.3% of its mother's body weight, making it one of the smallest eggs relative to the maternal weight in any bird species.[66] 15.7% of the weight of an emperor penguin egg is shell; like those of other penguin species, the shell is relatively thick, which minimises risk of breakage.[67]
After laying, the mother's nutritional reserves are exhausted and she very carefully transfers the egg to the male, before immediately returning to the sea for two months to feed.[62HP Pavilion dv5-2135dx CPU Fan ] The transfer of the egg can be awkward and difficult, and many couples drop the egg in the process. When this happens, the chick inside is quickly lost, as the egg cannot withstand the freezing temperatures on the icy ground. The male spends the winter incubating the egg in his brood pouch, balancing it on the tops of his feet, for 64 consecutive days until hatching.[6HP Envy 17-3000er CPU Fan 4] The emperor penguin is the only species where this behaviour is observed; in all other penguin species both parents take shifts incubating.[68] By the time the egg hatches, the male will have fasted for around 115 days since arriving at the colony.[64] To survive the cold and winds of up to 200 km/h (120 mph), the males huddle together, taking turns in the middle of the huddle. HP Envy 17 Series CPU FanThey have also been observed with their backs to the wind to conserve body heat. In the four months of travel, courtship, and incubation, the male may lose as much as 20 kg (44 lb), from around 38 kg to just 18 kg (84 lb to 40 lb).[69][70]
Hatching may take as long as two or three days to complete, as the shell of the egg is thick. HP 532614-001 CPU Fan Newly hatched chicks are semi-altricial, covered with only a thin layer of down and entirely dependent on their parents for food and warmth.[71] If the chick hatches before the mother's return, the father feeds it a curd-like substance composed of 59% protein and 28% lipid, which is produced by a gland in his esophagus.[72] HP Envy 17-3000er CPU FanThe young chick is brooded in what is called the guard phase, spending time balanced on its parent's feet and sheltered in the brood pouch.
The female penguin returns at any time from hatching to ten days afterwards, from mid-July to early August.[62] HP 532614-001 CPU Fan She finds her mate among the hundreds of fathers by his vocal call and takes over caring for the chick, feeding it by regurgitating the food that she has stored in her stomach. The male then leaves to take his turn at sea, spending around 24 days there before returning.[62] The parents then take turns, one brooding while the other forages at sea.[64] HP 532614-001 CPU Fan About 45–50 days after hatching, the chicks form a crèche, huddling together for warmth and protection. During this time, both parents forage at sea and return periodically to feed their chicks.[71] A crèche may comprise up to several thousand birds densely packed together and is essential for surviving the low Antarctic temperatures.[73] HP KSB06105HA CPU Fan From early November, chicks begin moulting into juvenile plumage, which takes up to two months and is often not completed by the time they leave the colony; adults cease feeding them during this time. All birds make the considerably shorter trek to the sea in December or January and spend the rest of the summer feeding there. HP 493001-001 CPU Fan The species has been bred outside Antarctica at SeaWorld San Diego; more than 20 individuals have hatched there since 1980.[75][76]Considered a flagship species, 55 individuals were counted in captivity in North American zoos and aquaria in 1999.[77] The species is kept in captivity in only two places in the world. Toshiba BFB0605HA CPU Fan In June 2011, a juvenile emperor penguin was found on the beach at Peka Peka, north of Wellington in New Zealand. He had been consuming 3 kg of sand, which he had mistaken for snow, as well as sticks and stones, and had to undergo a number of operations to remove these and save his life. HP Pavilion dv5-1174ca CPU Fan Following recovery, on 4 September, the juvenile, named "Happy Feet" (after the name of the 2006 film), was fitted with a tracking device and released into the Southern Ocean 80 km north of Campbell Island.[79][80][81] However, 8 days later scientists lost contact with the bird, suggesting that the transmitter had fallen off (considered likely) or that he had been eaten by a predator (considered less likely). Toshiba Satellite A110-101 CPU Fan The species' unique life cycle in such a harsh environment has been described in print and visual media. Apsley Cherry-Garrard, the Antarctic explorer, said: "Take it all in all, I do not believe anybody on Earth has a worse time than an emperor penguin".[83] Widely distributed in cinemas in 2005, the French documentary La Marche de l'empereur, HP Pavilion dv5-1174ca CPU Fan which was also released with the English title March of the Penguins, told the story of the penguins' reproductive cycle.[78][84] The subject has been covered for the small screen three times by the BBC and presenter David Attenborough, first in episode five of the 1993 series on the Antarctic Life in the Freezer,[85HP 535442-001 CPU Fan] again in the 2006 series Planet Earth,[86] and finally Frozen Planet in 2011.[87]
The computer-animated movie Happy Feet (2006) features emperor penguins as its primary characters, with one in particular that loves to dance; although a comedy, it too depicts their life cycle and promotes an underlying serious environmental message of threats from global warming and depletion of food sources by overfishing.[ HP Pavilion dv6-3049tx CPU Fan The computer-animated movie Surf's Up (2007) features a surfing emperor penguin named Zeke "Big-Z" Topanga.[89] More than 30 countries have depicted the bird on their stamps – Australia, Great Britain, Chile and France have each issued several.[90] It has also been depicted on a 1962 10 franc stamp as part of an Antarctic expedition series.[91] ACER Aspire 5730Z Series CPU FanCanadian band The Tragically Hip included a song "Emperor Penguin" on their 1998 album Phantom Power.
Ancient Greek is the form of Greek used during the periods of time spanning c. the 9th – 6th century BC (known asArchaic), c. the 5th – 4th century BC (Classical), and c. the 3rd century BC – 6th century AD (Hellenistic) in ancient Greece and the ancient world. HP KSB06105HA CPU Fan It was predated in the 2nd millennium BC by Mycenaean Greek. The language of the Hellenistic phase is known as Koine (common) or Biblical Greek, while the language from the late period onward features no considerable differences from Medieval Greek. Koine is regarded as a separate historical stage of its own, although in its earlier form, it closely resembled the Classical. HP Pavilion dv5-2135dx CPU FanPrior to the Koine period, Greek of the classic and earlier periods included several regional dialects.
Ancient Greek was the language of Homer and of classical Athenian historians, playwrights, and philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of theWest since the Renaissance. Toshiba Satellite L650-1MT CPU FanThis article primarily contains information about the Epic and Classical phases of the language.
The origins, early form and development of the Hellenic language family are not well understood because of the lack of contemporaneous evidence. There are several theories about what Hellenic dialect groups that may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language. SONY Vaio VGN-NW350F CPU FanThey have the same general outline but differ in some of the detail. The only attested dialect from this period[2] is Mycenaean, but its relationship to the historical dialects and the historical circumstances of the times imply that the overall groups already existed in some form.
The major dialect groups of the Ancient Greek period can be assumed to have developed not later than 1120 BC, at the time of the Dorian invasion(s), Toshiba Satellite M35X-S329 CPU Fan and their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to the historical Dorians; moreover, the invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. SONY Vaio VGN-TX2XP/B CPU Fan The Greeks of this period believed there were three major divisions of all Greek people—Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cyprian, far from the center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. LENOVO IdeaPad S10 20015 Laptop KeyboardWest vs. non-west Greek is the strongest marked and earliest division, with non-west in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcado-Cyprian, or Aeolic and Arcado-Cyprian vs. Ionic-Attic. Often non-west is called East Greek.
The Arcado-Cyprian group apparently descended more closely from the Mycenaean Greek of the Bronze Age. DELL Vostro 3550 Laptop KeyboardBoeotian had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect. Thessalian likewise had come under Northwest Greek influence, though to a lesser degree.
Pamphylian, spoken in a small area on the south-western coast of Asia Minor and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. TOSHIBA PK130260100 Laptop Keyboard Ancient Macedonian was an Indo-European language closely related to Greek, but its exact relationship is unclear because of insufficient data: possibly a dialect of Greek; a sibling language to Greek; or a close cousin to Greek, and perhaps related to some extent, to Thracian and Phrygian languages. Lenovo 45N2205 Laptop KeyboardThe Pella curse tablet is one of many finds that support the idea that the Ancient Macedonian language is closely related to the Doric Greek dialect.
Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. HP 636376-001 Laptop KeyboardDoric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric), Southern Peloponnesus Doric (including Laconian, the dialect ofSparta), and Northern Peloponnesus Doric (including Corinthian).
The Lesbian dialect was a member of the Aegean/Asiatic Aeolic sub-group. HP Pavilion dv6-2112sa Laptop KeyboardAll the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects.
The dialects outside the Ionic group are known mainly from inscriptions, HP 517865-031 Laptop Keyboardnotable exceptions being fragments of the works of the poetess Sappho from the island ofLesbos and the poems of the Boeotian poet, Pindar.
After the conquests of Alexander the Great in the late 300's BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek, but with influence from other dialects. HP Compaq NC8430 Laptop Keyboard This dialect slowly replaced most of the older dialects, although Doric dialect has survived to the present in the form of the Tsakonian dialect of Modern Greek, spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek. By about the 500's AD, the Koine had slowly metamorphosized into Medieval Greek. SAMSUNG NP-N102-JA01DX Laptop Keyboard Greek, like all of the older Indo-European languages, is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In Ancient Greek nouns (including proper nouns) have five cases (nominative, genitive, dative, accusative andvocative), three genders (masculine, feminine and neuter), and three numbers (singular, dual and plural). DELL V119525BS1 Laptop Keyboard Verbs have four moods(indicative, imperative, subjunctive, and optative), three voices (active, middle and passive), as well as three persons (first, second and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"): the present, future and imperfect are imperfective in aspect; TOSHIBA Satellite P500 Laptop Keyboardthe aorist (perfective aspect); a present perfect,pluperfect and future perfect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. There are infinitives and participles corresponding to the finite combinations of tense, aspect and voice. Lenovo ThinkPad Edge E520 Laptop Keyboard
The leopard seal (Hydrurga leptonyx), also referred to as the sea leopard, is the second largest species of seal in theAntarctic (after the southern elephant seal). It is most common in the Southern Hemisphere along the coast of Antarctica and on most sub-Antarctic islands, but can also be found on the coasts of southern Australia, TOSHIBA Satellite L300 Laptop KeyboardTasmania, South Africa, New Zealand, Lord Howe Island, Tierra del Fuego, the Cook Islands, and the Atlantic coast of South America. It can live 26 years, possibly more.[3]
Leopard seals are predators, feeding mainly on other seals, penguins, fish, and krill. Killer whales are the only known, albeit infrequent, natural predators of leopard seals.[4] DELL AEFM8U00310 Laptop KeyboardAlong with all of the other earless seals, it belongs to the family Phocidae, and is the only species in the genus Hydrurga. The name hydrurga means "water worker" and leptonyx is the Greek for "small clawed".
The leopard seal is large and muscular, with a dark grey back and light grey on its stomach. DELL 0P445M Laptop Keyboard Its throat is whitish with the black spots that give the seal its common name. Females are slightly larger than the males.[5] The overall length of this seal is 2.4–3.5 m (8.4–11.7 ft) and weight is from 200 to 600 kilograms (440 to 1,320 lb). They are about the same length as the northernwalrus, but usually less than half the weight.[6][7] TOSHIBA Mini NB 255-SP1002L Laptop KeyboardIts front teeth are sharp like those of other carnivores, but its molars lock together in a way that allows them to sieve krill from the water, in the manner of the crab eater seal.
The leopard seal lives in the cold waters surrounding Antarctica. During the summer months, it hunts among the pack ice surrounding the continent, spending almost all of its time in the water. SONY Vaio VGN-SZ73B/B CPU FanIn the winter, it ranges north to the sub-Antarctic islands. Occasionally, individuals may be spotted on the southern coasts of Argentina, Chile, Australia, and New Zealand, and as far north as the Cook Islands. Juveniles are more often found in the north.
The leopard seal is a solitary creature and comes together in small groups only when it is time to mate. Dell Latitude E6510 CPU Fan During the mating season, males and females make acoustic calls to each other over distances, with at least the males having individual variability in their vocalising sequence patterns.[8] After a 9-month gestation, the female digs a hole in the ice, and gives birth to a single pup during the Antarctic summer. She protects the pup until it is able to fend for itself. SONY UDQFRZH13CF0 CPU FanLeopard seals are not very vocal, although they occasionally make some grunting and growling noises.
The leopard seal is bold, powerful and curious. In the water, there is a fine line between curiosity and predatory behaviour, and it may 'play' with penguins it does not intend to eat. There are also records of leopard seals attacking divers. Paul Nicklen, a National Geographic magazinephotographer, HP Pavilion dv6-3370ca CPU Fancaptured pictures of a leopard seal bringing live, injured, and then dead penguins to him, possibly in an attempt to teach the photographer how to hunt.
The leopard seal is second only to the killer whale among Antarctica's top predators. Its canine teeth are 2.5 cm (1 in).[10] It feeds on a wide variety of creatures. Smaller seals probably eat mostly krill, but also squid and fish. HP G62-341NR CPU FanLarger leopard seals probably switch from krill to more substantial prey, including king, adelie, rockhopper, gentoo, emperor, and chinstrap penguins, and less frequently, other seals, such as crabeater seal.
Around the sub-Antarctic island of South Georgia, the Antarctic fur seal (Arctocephalus gazella) is the main prey. HP 535438-001 CPU FanOther prey include penguins and fish. Antarctic krill (Euphausia superba), southern elephant seal (Mirounga leonina) pups and seabirds other than penguins have also been found in leopard seal scats in small quantities.[11]
When hunting penguins, the leopard seal patrols the waters near the edges of the ice, almost completely submerged, waiting for the birds to enter the ocean. Dell Vostro 3450 CPU Fan It kills the swimming bird by grabbing the feet, then shaking the penguin vigorously and beating its body against the surface of the water repeatedly until the penguin is dead. Previous reports stating the leopard seal skins its prey before feeding have been found to be incorrect. DELL XPS M170 CPU FanLacking the teeth necessary to slice its prey into manageable pieces, it flails its prey from side to side to tear and rips it into smaller pieces.
The leopard seal is classified under the family Phocidae. Its closest relatives are the Ross seal, crabeater seal and the Weddell seal, which together are known as the lobodontine seals. SONY Vaio VGN-SZ2XP/C CPU FanAll these seals descend from the superfamily Pinnipeda, which evolved from bear-like ancestors. They have diverged from other taxa in the order Carnivora.
The leopard seal has many features analogous to other species. For example the forearm and hand bones are similar in structure to those found in many mammal, reptile, and bird species. HP Pavilion dv6z-3100 CTO CPU FanHowever, in the leopard seal, the fingers are covered in a web of skin, which they use to propel themselves through the water.
The leopard seals share homologous features with its close relatives, the lobodontine seals. They all have dark fur on the tops of their bodies and lighter fur on their underbellies. HP KSB06105HA CPU Fan Though the colors vary between these species, the colored fur serves the same function, which is camouflage against predators and as it stalks its prey. SONY Vaio VPC-EB2S1E/WI CPU Fan, Dell Vostro 3500 CPU Fan,ASUS BFB0705HA CPU Fan,HP Pavilion dv6720er CPU Fan,HP KSB06105HA CPU Fan
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