Banded penguin Temporal range: Middle Miocene-Recent | |
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Spheniscus demersus, the African penguin | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Sphenisciformes |
Family: | Spheniscidae |
Genus: | Spheniscus Brisson, 1760 |
Type species | |
Diomedea demersa [1] Linnaeus, 1758 | |
Species | |
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 braying. [2] 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. [3] [4]
Banded penguins belong to the genus Spheniscus, which was introduced by the French zoologist Mathurin Jacques Brisson in 1760 with the African penguin (Spheniscus demersus) as the type species. [5] [6] The genus name Spheniscus is derived from the Ancient Greek word σφήν (sphẽn) meaning "wedge" and is a reference to the animal's thin, wedge-shaped flippers. [7] [8]
The four extant species of banded penguins (Spheniscus) are:
Common name | Scientific name and subspecies | Range | Size and ecology | IUCN status and estimated population |
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Magellanic penguin | Spheniscus magellanicus (Forster, 1781) | Brazil, coastal Argentina, Chile and the Falkland Islands | Size: Habitat: Diet: | LC |
Humboldt penguin | Spheniscus humboldti Meyen, 1834 | coastal Chile and Peru | Size: Habitat: Diet: | VU |
Galapagos penguin | Spheniscus mendiculus Sundevall, 1871 | Galápagos Islands. | Size: Habitat: Diet: | EN |
African penguin, black-footed or jackass penguin | Spheniscus demersus (Linnaeus, 1758) | 24 islands and 3 mainland locations between Namibia and Algoa Bay, near Port Elizabeth, South Africa. | Size: Habitat: Diet: | CR |
Several extinct species are known from fossils:
The former Spheniscus predemersus is now placed in a monotypic genus Inguza .
Scientists believe that the genus Spheniscus originated in South America, even though the oldest fossils assigned to the taxon are from Antarctica. The oldest Spheniscus fossils are also the oldest penguin fossils from Antarctica. [14] African, Humboldt, and Magellanic penguins all live in temperate climates. The African penguin lives in South Africa, the Humboldt penguin lives in coastal Peru and Chile while the Magellanic penguin lives in coastal Chile, Argentina, and the Falkland Islands. Humboldt and Magellanic penguins are partially sympatric, since their ranges overlap in southern Chile. [15] [16] The Galápagos penguin is endemic to the Galápagos Islands, making it the most northerly of all penguin species. [17]
Banded penguins use vocalizations for localization, socialization and to allow recognition for conspecifics or mates. [18] Vocalizations in birds are produced by vibrations of the syrinx, located at the bottom of the trachea. [18] [4] These penguins are sometimes referred to as "jack-ass" penguins, since their vocalizations tend to sound similar to a donkey braying. [2] 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. [18] The 4 categories of vocalizations include contact calls, agonistic calls, ecstatic display songs or mutual display songs. [18]
Contact calls are vocalizations used primarily to maintain unity within a social group, to identify ones self and to maintain contact with a mate. [18] Vocal individuality has evolved in banded penguins due to their large social group sizes. [19] Contact calls are frequently used by banded penguins to form large flocks when foraging at sea. [18] 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. [18] 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. [20]
Agonistic calls are vocalizations used when a banded penguin is demonstrating agonistic behaviour, which is characterized by aggressive interactions or fighting. [4] Typically, banded penguins vocalize agonistic calls when defending a territory, such as their nest, against conspecifics. [18] For nesting penguin species, such as banded penguins, the mating pair and their offspring are the only individuals allowed on their nest. [21] Thus, any conspecific from the large colony that intrudes this territory will be a threat and an agonistic call will be produced. [21]
There are two types of display songs vocalized by banded penguins; ecstatic display songs and mutual display songs. [18] Ecstatic display songs are the loudest and most complex vocalization performed by banded penguins. [4] 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. [4] 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. [18] Typically, females respond more strongly to ecstatic display calls from their mates than from other conspecifics. [4] Furthermore, there is evidence to suggest that ecstatic display songs may convey vocal individuality through the type of syllables the song produces. [4] This vocal individuality can convey information such as body size and weight, since heavier penguins typically emit longer and lower-pitched vocalizations. [19] 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. [4]
The source-filter theory is a framework used for studying the communication of mammalian animals through vocalizations. [4] 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. [4] In mammals, the source is the vibrations in the larynx and the filter is the super laryngeal vocal tract. [4] 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. [4] 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. [4] The equivalence of the source-filter theory in humans is the source-filter model of speech production.
Penguins are a group of aquatic flightless birds from the family Spheniscidae of the order Sphenisciformes. They live almost exclusively in the Southern Hemisphere: only one species, the Galápagos penguin, is found north of the Equator. Highly adapted for life in the ocean water, penguins have countershaded dark and white plumage and flippers for swimming. Most penguins feed on krill, fish, squid and other forms of sea life which they catch with their bills and swallow whole while swimming. A penguin has a spiny tongue and powerful jaws to grip slippery prey.
The African penguin, also known as Cape penguin or South African penguin, is a species of penguin confined to southern African waters. Like all penguins, it is flightless, with a streamlined body and wings stiffened and flattened into flippers for a marine habitat. Adults weigh an average of 2.2–3.5 kg (4.9–7.7 lb) and are 60–70 cm (24–28 in) tall. The species has distinctive pink patches of skin above the eyes and a black facial mask. The body's upper parts are black and sharply delineated from the white underparts, which are spotted and marked with a black band.
The Humboldt penguin is a medium-sized penguin. It resides in South America, along the Pacific coast of Peru and Chile. Its nearest relatives are the African penguin, the Magellanic penguin and the Galápagos penguin. The Humboldt penguin and the cold water current it swims in both are named after the explorer Alexander von Humboldt. The species is listed as vulnerable by the IUCN with no population recovery plan in place. The current wild population is composed of roughly 23,800 mature individuals and is declining. It is a migrant species.
The Magellanic penguin is a South American penguin, breeding in coastal Patagonia, including Argentina, Chile, and the Falkland Islands, with some migrating to Brazil and Uruguay, where they are occasionally seen as far north as Espírito Santo. Vagrants have been found in El Salvador, the Avian Island in Antarctica, Australia, and New Zealand. It is the most numerous of the Spheniscus banded penguins. Its nearest relatives are the African penguin, the Humboldt penguin, and the Galápagos penguins. The Magellanic penguin was named after Portuguese explorer Ferdinand Magellan, who spotted the birds in 1520. The species is listed as being of Least Concern by the IUCN.
Phoca is a genus of the earless seals, within the family Phocidae. It now contains just two species, the common seal and the spotted seal. Several species formerly listed under this genus have been split into the genera Pusa, Pagophilus, and Histriophoca. Until recently, Phoca largha has been considered a subspecies of Phoca vitulina but now is considered its own species. For this reason, the fossil history of the genus is unclear, and it has formerly been used as wastebasket taxon for a number of fossils of uncertain affinity.
The emperor tamarin is a species of tamarin monkey allegedly named for its beard's resemblance to the German emperor Wilhelm II. It lives in the north Brazilian states of Acre and Amazonas and the southwest Amazon Basin, in east Peru, north Bolivia.
Palaeospheniscus is an extinct genus of penguins belonging to the subfamily Palaeospheniscinae. These penguins are apparently not closely related to the modern genus Spheniscus.
The Magellanic woodpecker is a species of large woodpecker found in southern Chile and southwestern Argentina; it is resident within its range. This species is the southernmost example of the genus Campephilus, which includes the famous ivory-billed woodpecker.
Whispering is an unvoiced mode of phonation in which the vocal cords are abducted so that they do not vibrate; air passes between the arytenoid cartilages to create audible turbulence during speech. Supralaryngeal articulation remains the same as in normal speech.
Agonistic behaviour is any social behaviour related to fighting. The term has broader meaning than aggressive behaviour because it includes threats, displays, retreats, placation, and conciliation. The term "agonistic behaviour" was first defined and used by J.P Scott and Emil Fredericson in 1951 in their paper "The Causes of Fighting in Mice and Rats" in Physiological Zoology.Agonistic behaviour is seen in many animal species because resources including food, shelter, and mates are often limited.
Elliot's storm petrel is a species of seabird in the storm petrel family Oceanitidae. The species is also known as the white-vented storm petrel. There are two subspecies, O. g. gracilis, which is found in the Humboldt Current off Peru and Chile, and O. g. galapagoensis, which is found in the waters around the Galápagos Islands. It is a sooty-black storm petrel with a white rump and a white band crossing the lower belly and extending up the midline of the belly. It has long legs which extend beyond the body in flight.
A courtship display is a set of display behaviors in which an animal, usually a male, attempts to attract a mate; the mate exercises choice, so sexual selection acts on the display. These behaviors often include ritualized movement ("dances"), vocalizations, mechanical sound production, or displays of beauty, strength, or agonistic ability.
The dear enemy effect or dear enemy recognition is an ethological phenomenon in which two neighbouring territorial animals become less aggressive toward one another once territorial borders are well established. As territory owners become accustomed to their neighbours, they expend less time and energy on defensive behaviors directed toward one another. However, aggression toward unfamiliar neighbours remains the same. Some authors have suggested the dear enemy effect is territory residents displaying lower levels of aggression toward familiar neighbours compared to unfamiliar individuals who are non-territorial "floaters".
Acrophyseter is a genus of extinct sperm whale that lived in the Late Miocene off the coast of what is now Peru. The genus comprises two species: A. deinodon and A. robustus. It is part of a group of macroraptorial sperm whales that all share several features for hunting large prey, such as deeply rooted and thick teeth. Acrophyseter measured 4–4.5 metres (13–15 ft) in length, making it the smallest macroraptorial sperm whale currently known. Because of its short pointed snout and strongly curved front teeth, it probably fed on the marine vertebrates of its time, such as seals and other whales.
The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica and Arequipa. The approximately 640 metres (2,100 ft) thick formation was deposited in the Pisco Basin, spanning an age from the Late Miocene up to the Early Pliocene, roughly from 9.6 to 4.5 Ma. The tuffaceous sandstones, diatomaceous siltstones, conglomerates and dolomites were deposited in a lagoonal to near-shore environment, in bays similar to other Pacific South American formations as the Bahía Inglesa and Coquimbo Formations of Chile.
Caleta Herradura Formation is a geologic formation of Late Miocene (Montehermosan) age, cropping out on the Mejillones Peninsula in northern Chile. The erosion at the Coastal Cliff of northern Chile have created particularly good exposures of Caleta Herradura Formation. The formation deposited in a half graben within Mejillones Peninsula. The formation rests nonconformably on the Jorgino Formation.
Spheniscus muizoni is an extinct species of banded penguins that lived during the early Late Miocene in what is now Peru, South America. The species, the earliest member of the extant genus, was described in 2007 by Ursula B. Göhlich based on fossils found in the fossiliferous Pisco Formation of the Pisco Basin, southwestern Peru.
Spheniscus megaramphus is an extinct species of penguin that lived during the Late Miocene South America. It is notable for being the largest known species of banded penguin, along with having a proportionally large beak.
Spheniscus anglicus is an extinct species of banded penguin that lived during the Late Miocene in what is now Chile, South America. The species was described in 2015 by Richard D. Benson based on a fossil found in the Bahia Inglesa Formation in northern Chile.
Spheniscus chilensis is an extinct species of penguin that lived during the Late Pliocene in Chile. The first fossil record of the penguin was discovered on the coast of Antofagasta in 1980, when coastal erosion exposed the first fossilized bone.