Crested penguin Temporal range: Miocene to present | |
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Macaroni penguin, Eudyptes chrysolophus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Sphenisciformes |
Family: | Spheniscidae |
Genus: | Eudyptes Vieillot, 1816 |
Type species | |
Aptenodytes chrysocome [1] | |
Species | |
Eudyptes chrysocome Contents |
Eudyptes is a genus of penguins whose members are collectively called crested penguins. [2] The exact number of species in the genus varies between four and seven depending on the authority, and a Chatham Islands species became extinct in recent centuries. All are black and white penguins with yellow crests, red bills and eyes, and are found on Subantarctic islands in the world's southern oceans. All lay two eggs, but raise only one young per breeding season; the first egg laid is substantially smaller than the second.
The genus Eudyptes was introduced by the French ornithologist Louis Pierre Vieillot in 1816; [3] the name is derived from the Ancient Greek words eu meaning "fine", and dyptes meaning "diver". [4] The type species was designated as the southern rockhopper penguin by George Robert Gray in 1840. [5] [6]
Six extant species have been classically recognised, with the recent splitting of the rockhopper penguin increasing it to seven. Conversely, the close relationship of the macaroni and royal penguins, and the erect-crested and Snares penguins have led some to propose that the two pairs should be regarded as species. [7]
Order Sphenisciformes
The Chatham Islands Eudyptes warhami is known only from subfossil bones, and became extinct shortly following human colonisation of the Chatham Islands. This genetically-distinct species was relatively large, with a thin, slim and low bill. (T.L. Cole et al. (2019) Mol. Biol. Evol.)
Mitochondrial and nuclear DNA evidence suggests that the crested penguins split from the ancestors of their closest living relative, the yellow-eyed penguin, in the mid-Miocene around 15 million years ago, before splitting into separate species around 8 million years ago in the late Miocene. [8]
A fossil penguin genus, Madrynornis , has been identified as the closest known relative of the crested penguins. Found in late Miocene deposits dated to about 10 million years ago, it must have separated from the crested penguins around 12 million years ago. Given that the head ornamentation by yellow filoplumes seems plesiomorphic for the Eudyptes-Megadyptes lineage, Madrynornis probably had them too.[ citation needed ]
Common name | Scientific name and subspecies | Range | Size and ecology | IUCN status and estimated population |
---|---|---|---|---|
Fiordland penguin | Eudyptes pachyrhynchus G. R. Gray, 1845 | New Zealand. | Size: Habitat: Diet: | NT |
Snares penguin | Eudyptes robustus Oliver, 1953 | New Zealand. | Size: Habitat: Diet: | VU |
Erect-crested penguin | Eudyptes sclateri (Buller, 1888) | New Zealand, Bounty and Antipodes Islands. | Size: Habitat: Diet: | EN |
Southern rockhopper penguin | Eudyptes chrysocome (Forster, JR, 1781) Two subspecies
| Kerguelen Islands and subantarctic islands of New Zealand, Cape Horn to the Falkland Islands | Size: Habitat: Diet: | VU |
Northern rockhopper penguin | Eudyptes moseleyi Mathews & Iredale, 1921 | southern Indian and Atlantic Oceans | Size: Habitat: Diet: | EN |
Royal penguin | Eudyptes schlegeli Finsch, 1876 | sub-Antarctic Macquarie Island and adjacent islands. | Size: Habitat: Diet: | LC |
Macaroni penguin | Eudyptes chrysolophus (Brandt, 1837) | Subantarctic to the Antarctic Peninsula | Size: Habitat: Diet: | LC |
The crested penguins are all similar in appearance, having sharply delineated black and white plumage with red beaks and prominent yellow crests. Their calls are more complex than those of other species, with several phrases of differing lengths. [9] The royal penguin (mostly) has a white face, while other species have black faces.
Crested penguins breed on Subantarctic islands in the southern reaches of the world's oceans; the greatest diversity occurring around New Zealand and surrounding islands. Their breeding displays and behaviours are generally more complex than other penguin species. [10] Both male and female parents take shifts incubating eggs and young. [11]
Crested penguins lay two eggs, but almost always raise only one young successfully. All species exhibit the odd phenomenon of egg-size dimorphism in breeding; the first egg (or A-egg) laid is substantially smaller than the second egg (B-egg). This is most extreme in the macaroni penguin, where the first egg averages only 60% the size of the second. [12] The reason for this is a mystery remains unknown, although several theories have been proposed. British ornithologist David Lack theorized that the genus was evolving toward the laying of a one-egg clutch. [13] Experiments with egg substitution have shown that A-eggs can produce viable chicks that were only 7% lighter at time of fledging. [14] Physiologically, the first egg is smaller because it develops while the mother is still at sea swimming and thus has less energy to invest in the egg. [15]
Recently, brooding royal and erect-crested penguins have been reported[ by whom? ] to tip the smaller eggs out as the second is laid.
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 southern rockhopper penguin is a species of rockhopper penguin, that is sometimes considered distinct from the northern rockhopper penguin. It occurs in subantarctic waters of the western Pacific and Indian Oceans, as well as around the southern coasts of South America.
The macaroni penguin is a species of penguin found from the Subantarctic to the Antarctic Peninsula. One of six species of crested penguin, it is very closely related to the royal penguin, and some authorities consider the two to be a single species. It bears a distinctive yellow crest that resembles a hairdo consisting of macaroni, from which its name is derived. Its face and upperparts are black and sharply delineated from the white underparts. Adults weigh on average 5.5 kg (12 lb) and are 70 cm (28 in) in length. The male and female are similar in appearance; the male is slightly larger and stronger with a relatively larger bill. Like all penguins, it is flightless, with a streamlined body and wings stiffened and flattened into flippers for a marine lifestyle.
The erect-crested penguin is a penguin endemic to the New Zealand region and only breeds on the Bounty and Antipodes Islands. It has black upper parts, white underparts and a yellow eye stripe and crest. It spends the winter at sea and little is known about its biology and breeding habits. Populations are believed to have declined during the last few decades of the twentieth century, and the International Union for Conservation of Nature has listed it as being "endangered".
The Snares penguin, also known as the Snares crested penguin and the Snares Islands penguin, is a penguin from New Zealand. The species breeds on the Snares Islands, a group of islands off the southern coast of the South Island. It is a yellow-crested penguin, with a size of 50–70 cm (19.5–27.5 in) and a weight of 2.5–4 kg (5.5–8.8 lb). It has dark blue-black upper parts and white underparts. It has a bright yellow eyebrow-stripe which extends over the eye to form a drooping, bushy crest. It has bare pink skin at the base of its large red-brown bill.
The Fiordland penguin, also known as the Fiordlandcrested penguin, is a crested penguin species endemic to New Zealand. It currently breeds along the south-western coasts of New Zealand's South Island as well as on Stewart Island/Rakiura and its outlying islands. Because it originally ranged beyond Fiordland, it is sometimes referred to as the New Zealand crested penguin. It is occasionally found in Australia.
The royal penguin is a species of penguin, which can be found on the sub-Antarctic Macquarie Island and adjacent islands. The International Union for Conservation of Nature (IUCN) classifies the royal penguin as Least Concern. The scientific name commemorates the German zoologist Hermann Schlegel.
The rockhopper penguins are three closely related taxa of crested penguins that have been traditionally treated as a single species and are sometimes split into three species.
Flightless birds are birds that, through evolution, lost the ability to fly. There are over 60 extant species, including the well-known ratites and penguins. The smallest flightless bird is the Inaccessible Island rail. The largest flightless bird, which is also the largest living bird in general, is the ostrich.
The Chatham penguin, also known as the Chatham crested penguin, Chatham Islands penguin, or Warham's penguin, is an extinct species of crested penguin previously endemic to the Chatham Islands of New Zealand. It is known only from subfossil bones and probably became extinct within 150–200 years after Polynesians arrived in the Chatham Islands around 1500 CE.
The Southern Indian Ocean Islands tundra is a tundra ecoregion that includes several subantarctic islands in the southern Indian Ocean.
The northern rockhopper penguin, Moseley's rockhopper penguin, or Moseley's penguin is a penguin species native to the southern Indian and Atlantic Oceans. It is described as distinct from the southern rockhopper penguin.
The eastern rockhopper penguin, also known as the tawaki piki toka, is a crested penguin with yellow crest feathers. It is a subspecies of the southern rockhopper penguin found in subantarctic regions and the Indian Ocean. It is one of the smallest crested penguins and has distinctive pink margins around its bill.
Eudyptes calauina is an extinct species of crested penguin that lived during the Late Pliocene. It inhabited what is now central Chile.