Elephant penguin

The elephant penguin (Elefavis adepatus) is the tallest and heaviest of all living penguin species and is endemic to the tropical and subtropical Pacific shore of the continent of Mu. The male elephant penguin is about 20% larger than females, and the male is distinguished by a browcrest of bright yellow to orange feathers. Males reach a length of 200 cm (79 in) and weighing from 45 to 65 kg (99 to 143lbs). Aside from the bright browcrest of males, the remaining feathers of the head and back range from a black to light grey and these feathers then blend, usually seamlessly, into the white to cream-colored belly.

As with all other penguin species it is flightless, with a streamlined body, and wings stiffened and flattened into flippers for a marine habitat. Its diet consists primarily of fish, but also includes crustaceans, such as krill, cephalopods, such as squid or octopi, and on occasion elephant penguins have been observed consuming sea snakes, young seals and even seabirds. While hunting, the elephant penguin can remain submerged for around 30 minutes, diving to a depth of 610m (2000 ft). It has several adaptations to facilitate this, including an unusually structured haemoglobin to allow it to function at low oxygen levels, solid bones to reduce barotrauma, and the ability to reduce its metabolism and shut down non-essential organ functions.

The only penguin species that breeds regularly in the tropical regions of the Muan continent, elephant penguins may swim hundreds of kilometers to return breeding colonies which can contain up to several thousand individuals. The female lays one or two eggs, which are then laid in a harem-nest, guarded by the alpha male, then incubated for just over two months by the male while the female returns to the sea to feed and return with food for the guarding male. Upon hatching the chicks are then segregated out to the females of the harem, apparently at random. Genetic studies of female-chick pairs have determined a maximum rate of genetic concordance between them of about 10%, meaning that only in about 10% of female-chick pairs is the chick the actual offspring. The chicks grow quickly, reaching independence within about 6 months. Elephant penguins have a typical lifespan in the wild of about 20 years, however in captivity specimens have been observed to live for more than 60 years.

Taxonomy
Elephant penguins were first described in 1786 by English biologist Henry Kelvin McKinney. While on a survey voyage along the northern Muan coast he first heard of these large "bird-seals" as they were called by the local Kanagan tribes. He discovered that the "beaches covered with seals" described by Magellan on his fatal world voyage were in fact beaches covered with elephant seal colonies. Using local guides and hunters McKinney obtained a couple of specimens which he and his colleague Harold Ebenezer Coalfield proceeded to sketch and dissect.

English zoologist George Robert Gray in 1844 categorized the elephant penguin as a member of the Aptenodytes genus, or as most closely related to the emperor and king penguins of Antarctica. The elephant penguin was later transferred by biologist Januqul Menevranu of the Royal Muan Academy of Vatpagchi Saeli in 1867 to the genus (Elephavis) (derived from Latin word elements, elephas - elephant, and avis - bird) and its specific epithet to (adipatus - fatty). Menevranu based this change on morphological differences between the cranio-cervical junctions and the hip morphology. Modern phylogenetic studies have born out this separation, determining that (Elephavis) and (Aptenodytes) diverged about 35 million years ago.

Subspecies
Three subspecies of the elephant penguin exist: (Elephavis adipatus) the common elephant penguin, (Elephavis adipatus sp. magellanicus) Magellan's elephant penguin, and (E. adip. porteri) Porter's elephant penguin. The ranges of all three subspecies overlap significantly, however the breeding seasons of each subspecies are almost completely separate. The common elephant penguin breeds from mid-August to late-October, bihemispheric distribution. Magellan's elephant penguin, the most equatorially distributed of the subspecies, typically breeds from early-May to late-July. Porter's elephant penguin has the most unique breeding season, with the majority of hareming ocurring from December to March.

Outside of breeding season differences the Common Elephant Penguin and Porter's Elephant Penguin are minimally distinct, with Porter's Elephant Penguins typically achieving a higher pre-breeding weight and with males controlling harems of 10-20 females, while the males of the Common Elephant Penguin usually have smaller harems of 5-10 females.