The banded penguins are penguins that belong to the genus ''Spheniscus''. There are four living species, all with similar banded plumage-patterns. They are sometimes also known as "jack-ass penguins" due to their loud locator-calls sounding similar to a

donkey The donkey or ass is a domesticated equine. It derives from the African wild ass, ''Equus africanus'', and may be classified either as a subspecies thereof, ''Equus africanus asinus'', or as a separate species, ''Equus asinus''. It was domes ...

braying. Common traits include a band of black that runs around their bodies bordering their black dorsal coloring, black beaks with a small vertical white band, distinct spots on their bellies, and a small patch of unfeathered or thinly feathered skin around their eyes and underdeveloped fluff sack that can be either white or pink. All members of this genus lay eggs and raise their young in nests situated in burrows or in natural depressions in the earth.

Systematics

Banded penguins belong to the genus ''Spheniscus'', which was introduced by the French zoologist

Mathurin Jacques Brisson Mathurin Jacques Brisson (; 30 April 1723 – 23 June 1806) was a French zoologist and natural philosophy, natural philosopher. Brisson was born on 30 April 1723 at Fontenay-le-Comte in the Vendée department of western France. Note that page 14 ...

in 1760 with the African penguin (''Spheniscus demersus'') as the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

. The genus name ''Spheniscus'' is derived from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

word σφήν (''sphẽn'') meaning "wedge" and is a reference to the animal's thin, wedge-shaped flippers.

Species

Extant

The four extant species of banded penguins (''Spheniscus'') are:

Extinct

Several

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

species are known from fossils: * '' Spheniscus anglicus'' (

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

of Chile) * '' Spheniscus chilensis'' (

Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d ...

of Chile) * '' Spheniscus megaramphus'' (Late Miocene/Early Pliocene of Peru and Chile)Stucchi, 2007, p.370 * '' Spheniscus muizoni'' (Middle/Late Miocene of Cerro La Bruja, Peru)Göhlich, 2007, p.287 * '' Spheniscus urbinai'' (Late Miocene/Early Pliocene of Peru and Chile) The former ''Spheniscus predemersus'' is now placed in a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus '' Inguza''.

Range

Scientists believe that the genus ''Spheniscus'' originated in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

, even though the oldest

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s assigned to the

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

are from

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

. The oldest ''Spheniscus'' fossils are also the oldest penguin fossils from Antarctica. African, Humboldt, and Magellanic penguins all live in temperate climates. The African penguin lives in

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, the Humboldt penguin lives in coastal

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

and

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

while the Magellanic penguin lives in coastal Chile,

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

, and the

Falkland Islands The Falkland Islands (; ), commonly referred to as The Falklands, is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and from Cape Dub ...

. Humboldt and Magellanic penguins are partially sympatric, since their ranges overlap in southern

. The Galápagos penguin is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the

Galápagos Islands The Galápagos Islands () are an archipelago of volcanic islands in the Eastern Pacific, located around the equator, west of the mainland of South America. They form the Galápagos Province of the Republic of Ecuador, with a population of sli ...

, making it the most northerly of all penguin species.

Vocalizations

Banded penguins use vocalizations for localization, socialization and to allow recognition for conspecifics or mates. Vocalizations in birds are produced by vibrations of the syrinx, located at the bottom of the trachea. These penguins are sometimes referred to as "jack-ass" penguins, since their vocalizations tend to sound similar to a

braying. Vocalizations in adult penguins can be classified into 4 distinct categories based on its acoustic properties and the behavioural context in which a vocalization is produced. The 4 categories of vocalizations include contact calls, agonistic calls, ecstatic display songs or mutual display songs.

Contact calls

Contact calls are vocalizations used primarily to maintain unity within a social group, to identify ones self and to maintain contact with a mate. Vocal individuality has evolved in banded penguins due to their large social group sizes. Contact calls are frequently used by banded penguins to form large flocks when foraging at sea. It is easy to become separated while diving for food, therefore these penguins use contact calls to stay in contact with each other when they are out of sight. A contact call can relay an excess of information about an individual penguin, including the penguins sex, age, social status within a group and emotional state.

Agonistic calls

Agonistic calls are vocalizations used when a banded penguin is demonstrating agonistic behaviour, which is characterized by aggressive interactions or fighting. Typically, banded penguins vocalize agonistic calls when defending a territory, such as their nest, against conspecifics. For nesting penguin species, such as banded penguins, the mating pair and their offspring are the only individuals allowed on their nest. Thus, any conspecific from the large colony that intrudes this territory will be a threat and an agonistic call will be produced.

Display songs

There are two types of display songs vocalized by banded penguins; ecstatic display songs and mutual display songs. Ecstatic display songs are the loudest and most complex vocalization performed by banded penguins. They are composed of a sequence of distinct acoustic syllables that combine to form a complete phrase and are often displayed during their breeding season. Despite the close relatedness of banded penguin species, the ecstatic display calls of African, Humboldt and Magellanic penguins are distinctly recognizable, even to human listeners. Typically, females respond more strongly to ecstatic display calls from their mates than from other conspecifics. Furthermore, there is evidence to suggest that ecstatic display songs may convey vocal individuality through the type of syllables the song produces. This vocal individuality can convey information such as body size and weight, since heavier penguins typically emit longer and lower-pitched vocalizations. Mutual display songs are similar to ecstatic display songs in that they are also complex sequences of acoustic syllables. However, mutual display songs are performed by mates at their nesting site.

Source-filter theory

The source-filter theory is a framework used for studying the communication of

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

ian animals through vocalizations. According to this theory, acoustic calls are produced by a source and then must be filtered to remove certain frequencies or leave others unchanged, which produces vocal individuality. In mammals, the source is the vibrations in the larynx and the filter is the super laryngeal vocal tract. However, birds use a different source and filter to produce vocalizations. They use a structure called the syrinx as their source of vibrations and their trachea acts as the filter. The source-filter theory has become increasingly popular to study birds, such as various species of banded penguins. This theory can be used to investigate how acoustic variation and individuality within a set of closely related species is attributed to distinct morphological differences in their vocal organs. The equivalence of the source-filter theory in humans is the source-filter model of speech production.

References

Bibliography

* *

External links

www.pinguins.info: information about all species of penguins
{{DEFAULTSORT:Banded penguin Penguins