Crested penguin

{{Short description|Genus of birds}} {{Automatic taxobox | fossil_range = Miocene to present | image = Macaroni (js)1.jpg | image_caption = Macaroni penguin, ''Eudyptes chrysolophus'' | taxon = Eudyptes | authority = Vieillot, 1816 | type_species = ''Aptenodytes chrysocome''<ref>{{ cite book | last=Gray | first=George Robert | author-link=George Robert Gray | year=1840 | title=A List of the Genera of Birds : with an Indication of the Typical Species of Each Genus | location=London | publisher=R. and J.E. Taylor | page=77 | url=https://www.biodiversitylibrary.org/page/13668994 }}</ref> | subdivision_ranks = Species | subdivision = ''Eudyptes chrysocome'' ''Eudyptes chrysolophus'' ''Eudyptes moseleyi'' ''Eudyptes filholi'' ''Eudyptes pachyrhynchus'' ''Eudyptes robustus'' ''Eudyptes schlegeli'' ''Eudyptes sclateri'' ''†Eudyptes warhami'' ''†Eudyptes calauina'' ''†Eudyptes atatu'' }}

'''''Eudyptes''''' (from Ancient Greek εὖ (''eû''), meaning "true, well", and δύπτης (''dúptes''), meaning "diver", and thus, "true diver") is a genus of penguins whose members are collectively called '''crested penguins'''.<ref>{{cite web|url=https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=174451|title=ITIS Standard Report Page: Eudyptes|publisher=}}</ref> The exact number of species in the genus varies between four and eight 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.

==Taxonomy== The genus ''Eudyptes'' was introduced by the French ornithologist Louis Pierre Vieillot in 1816;<ref>{{cite book | last=Vieillot | first=Louis Pierre | author-link=Louis Pierre Vieillot | year=1816 | title=Analyse d'une Nouvelle Ornithologie Élémentaire| publisher=Deterville/self | location=Paris | pages=67, 70 | language=French| url=https://gallica.bnf.fr/ark:/12148/bpt6k9745205x/f73.item }} The genus name is misspelled as ''Endyptes'' on page 67.</ref> the name is derived from the Ancient Greek words {{Transliteration|grc|eu}} meaning "fine", and {{Transliteration|grc|dyptes}} meaning "diver".<ref>{{cite book | last=Jobling | first=James A. | year=2010| title=The Helm Dictionary of Scientific Bird Names | publisher=Christopher Helm | location=London | isbn=978-1-4081-2501-4 | page=152 | url=https://archive.org/stream/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling#page/n152/mode/1up }}</ref> The type species was designated as the western rockhopper penguin by George Robert Gray in 1840.<ref>{{ cite book | last=Gray | first=George Robert | author-link=George Robert Gray | year=1840 | title=A List of the Genera of Birds : with an Indication of the Typical Species of Each Genus | location=London | publisher=R. and J.E. Taylor | page=77 | url=https://www.biodiversitylibrary.org/page/13668994 }}</ref><ref>{{ cite book | editor1-last=Mayr | editor1-first=Ernst | editor1-link=Ernst Mayr | editor2-last=Cottrell | editor2-first=G. William | year=1979 | title=Check-List of Birds of the World | volume=1 | edition=2nd | publisher=Museum of Comparative Zoology | location=Cambridge, Massachusetts | page=126 | url=https://www.biodiversitylibrary.org/page/16108766 }}</ref>

The genus contains eight exant species:<ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | editor3-last=Rasmussen | editor3-first=Pamela | editor3-link=Pamela C. Rasmussen | date=February 2025 | title=Kagu, Sunbittern, tropicbirds, loons, penguins | work=IOC World Bird List Version 15.1 | url=https://www.worldbirdnames.org/bow/loons/ | publisher=International Ornithologists' Union | access-date=5 March 2025 }}</ref> * Macaroni penguin, ''Eudyptes chrysolophus'' * Royal penguin, ''Eudyptes schlegeli'' * Northern rockhopper penguin, ''Eudyptes moseleyi'' (formerly a subspecies of ''E. chrysocome'') * Eastern rockhopper penguin, ''Eudyptes filholi'' (formerly a subspecies of ''E. chrysocome'') * Western rockhopper penguin, ''Eudyptes chrysocome'' (Formerly southern rockhopper penguin before split) * Fiordland penguin, ''Eudyptes pachyrhynchus'' * Snares penguin, ''Eudyptes robustus'' * Erect-crested penguin, ''Eudyptes sclateri''

Also a fossil species: * Chatham penguin, ''Eudyptes warhami'' (extinct)

''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.

===Evolution=== thumb|left|''Madrynornis'' fossil 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.<ref>{{cite journal |vauthors=Baker AJ, Pereira SL, Haddrath OP, Edge KA|year=2006|title=Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling |journal=Proc Biol Sci |volume=273 |issue=1582|pages=11–17|doi=10.1098/rspb.2005.3260 |pmid=16519228 |pmc=1560011}}</ref>

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|date=January 2024}}

===Extant Species=== {{Species table |genus= Eudyptes |authority-name=Vieillot |authority-year=1816 |species-count=Eight|no-note=y|narrow-percent=75}}

{{Species table/row |name=Fiordland penguin |binomial=Eudyptes pachyrhynchus |image=File:Fiordland penguin (Mattern).jpg|image-size=180px |image-alt= |authority-name=G. R. Gray |authority-year=1845 |authority-not-original= |range= New Zealand. |range-image=File:Fiordland Penguin distribution map.png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= NT |population= |direction= |subspecies= }}

{{Species table/row |name=Snares penguin |binomial=Eudyptes robustus |image=File:Snares Penguin, Southland, NZ imported from iNaturalist photo 347215306.jpg|image-size=180px |image-alt= |authority-name=Oliver |authority-year= 1953 |authority-not-original= |range= New Zealand. |range-image=File:Manchot carte repartition gorfou snares.png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= VU |population= |direction= |subspecies= }}

{{Species table/row |name=Erect-crested penguin |binomial=Eudyptes sclateri |image=File:Erect-crested penguin (Eudyptes sclateri).jpg|image-size=180px |image-alt= |authority-name=Buller |authority-year=1888 |authority-not-original=yes |range= New Zealand, Bounty and Antipodes Islands. |range-image=File:Eudyptes sclateri distribution (breeding).png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= EN |population= |direction= |subspecies= }}

{{Species table/row |name=Western rockhopper penguin |binomial=Eudyptes chrysocome |image=File:Rockhopper Penguin on Saunders Island (5586446214).jpg|image-size=180px |image-alt= |authority-name=Forster, JR |authority-year=1781 |authority-not-original=yes |range=Kerguelen Islands and subantarctic islands of New Zealand, Cape Horn to the Falkland Islands |range-image= File:Appearance Eudyptes chrysochome.png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= VU |population= |direction= }}

{{Species table/row |name=Eastern rockhopper penguin |binomial=Eudyptes filholi |image=File:Eastern Rockhopper Penguin, Musgrave Inlet, Auckland Island, Auckland Islands, Southland, New Zealand imported from iNaturalist photo 500379206 (cropped 2).jpg|image-size=180px |image-alt= |authority-name=Hutton, FW |authority-year=1879 |authority-not-original= |range=Prince Edward, Crozet, Kerguelen, Heard, Macquarie, Antipodes, Auckland and Campbell Islands |range-image= |range-image-size= |size= |habitat= |hunting= |iucn-status= |population= |direction= }}

{{Species table/row |name=Northern rockhopper penguin |binomial=Eudyptes moseleyi |image=File:Eudyptes moseleyi -Zoologischer Garten Berlin, Germany-8a.jpg|image-size=180px |image-alt= |authority-name=Mathews & Iredale |authority-year=1921 |authority-not-original= |range= southern Indian and Atlantic Oceans |range-image=File:Appearance Eudyptes chrysochome.png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= EN |population= |direction= |subspecies= }}

{{Species table/row |name=Royal penguin |binomial=Eudyptes schlegeli |image=File:RoyalPenguins3.JPG|image-size=180px |image-alt= |authority-name=Finsch |authority-year=1876 |authority-not-original= |range= sub-Antarctic Macquarie Island and adjacent islands. |range-image=File:Eudyptes schlegeli distribution (nesting).png |range-image-size=180px |size= |habitat= |hunting= |iucn-status= LC |population= |direction= |subspecies= }}

{{Species table/row |name=Macaroni penguin |binomial=Eudyptes chrysolophus |image=File:Macaroni penguin half moon island 1.17.25 DSC 9137-topaz-rawdenoise (cropped).jpg|image-size=180px |image-alt= |authority-name=Brandt|authority-year=1837 |authority-not-original=yes |range= Subantarctic to the Antarctic Peninsula |range-image=File:Macaroni penguin rangemap.svg |range-image-size=180px |size= |habitat= |hunting= |iucn-status= LC |population= |direction= |subspecies= }} {{Species table/end}}

==Description== 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.<ref name=Williams69>Williams ''(The Penguins)'' p. 69</ref> The royal penguin (mostly) has a white face, while other species have black faces.

==Breeding== 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.<ref name=Williams52>Williams ''(The Penguins)'' p. 52</ref> Both male and female parents take shifts incubating eggs and young.<ref name=Williams76>Williams ''(The Penguins)'' p. 76</ref>

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.<ref name=Williams38>Williams ''(The Penguins)'' p. 38</ref> The reason for this 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.<ref>{{cite book|last=Lack|first=David|title=Ecological Adaptations for breeding in birds|url=https://archive.org/details/ecologicaladapta0000lack|url-access=registration|publisher=Methuen|location=London|year=1968}}</ref> Experiments with egg substitution have shown that A-eggs can produce viable chicks that were only 7% lighter at time of fledging.<ref>{{cite journal|doi=10.2307/3545145|last=Williams|first=Tony D|year=1990|title=Growth and survival in the Macaroni Penguin ''Eudyptes chrysolophus'', A- and B-chicks: do females maximise investment in the large B-egg|journal=Oikos|volume=59|issue=3|pages=349–54|jstor=3545145}}</ref> 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.<ref>{{cite news|last1=Young|first1=Ed|title=Why Crested Penguins Always Lay Doomed Eggs|url=http://news.nationalgeographic.com/2016/10/why-penguins-lay-two-eggs-science/|archive-url=https://web.archive.org/web/20161006134303/http://news.nationalgeographic.com/2016/10/why-penguins-lay-two-eggs-science/|url-status=dead|archive-date=October 6, 2016|accessdate=10 October 2016|work=National Geographic|date=4 October 2016}}</ref>

Recently, brooding royal and erect-crested penguins have been reported{{by whom|date=December 2011}} to tip the smaller eggs out as the second is laid.

==References== {{Reflist|30em}}

===Cited text=== * {{cite book | last=Williams | first=Tony D | year=1995 | title=The Penguins | location=Oxford, England | publisher=Oxford University Press|isbn=0-19-854667-X}} * Cole, Theresa L.; Ksepka, Daniel T.; Mitchell, Kieren J.; Tennyson, Alan J. D.; Thomas, Daniel B.; Pan, Hailin; Zhang, Guojie; Rawlence, Nicolas J.; Wood, Jamie R.; Bover, Pere; Bouzat, Juan L.; Cooper, Alan; Fiddamanl, Steven; Hart, Tom; Miller, Gary; Ryan, Peter G.; Shepherd, Lara D.; Wilmshurst, Janet M.; Waters, Jonathan M. (2019). "Mitogenomes uncover extinct penguin taxa and reveal island formation as a key driver of speciation". Molecular Biology and Evolution. doi:10.1093/molbev/msz017.

==External links== * [https://www.terranature.org/penguin.htm TerraNature.org: "Three ''Eudyptes'' species endemic to New Zealand"]

. Category:Penguins Category:Spheniscidae Category:Taxa named by Louis Pierre Vieillot