Editing Tern (section)

== Taxonomy ==
The bird [[order (biology)|order]] [[Charadriiformes]] contains 18 [[seabird|coastal seabird]] and [[wader]] [[family (biology)|families]]. Within the order, the terns form a lineage with the [[gull]]s, and, less closely, with the [[Skimmer (bird)|skimmer]]s, [[skua]]s, and [[auk]]s.<ref>{{cite journal | last1 = Paton | first1 = Tara A | last2 = Baker | first2 = Allan J | last3 = Groth | first3 = Jeffrey G | last4 = Barrowclough | first4 = George F | year = 2003 | title = RAG-1 sequences resolve phylogenetic relationships within charadriiform birds |journal = Molecular Phylogenetics and Evolution | volume = 29 | pages = 268–278 | doi = 10.1016/S1055-7903(03)00098-8 | pmid = 13678682 | issue = 2 | bibcode = 2003MolPE..29..268P }}</ref><ref name=tuinen>{{cite journal | last= van Tuinen | first= Marcel | author2=Waterhouse, David M| author3=Dyke, Gareth J | year= 2004 | title= Avian molecular systematics on the rebound: a fresh look at modern shorebird phylogenetic relationships | journal= Journal of Avian Biology | volume= 35 | issue = 3 | pages= 191–194 |doi = 10.1111/j.0908-8857.2004.03362.x}}</ref> Early authors such as [[Conrad Gessner]], [[Francis Willughby]], and [[William Turner (naturalist)|William Turner]] did not clearly separate terns from gulls,<ref name = hume12/> but [[Carl Linnaeus|Linnaeus]] recognised the distinction in his 1758 ''[[Systema Naturae]]'', placing the gulls in the genus '' [[Larus]]'' and the terns in ''Sterna''. He gave ''Sterna'' the description ''rostrum subulatum'', "[[bradawl|awl-shaped]] bill", referring to the long, pointed bills typical of this group of birds, a feature that distinguishes them from the thicker-billed gulls.<ref name = linn84>Linnaeus (1758) p. 84.</ref><ref name= job338>Jobling (2010) p. 338.</ref><ref>{{cite book | title = The Chambers Dictionary |edition=ninth | year = 2006 | publisher = Chambers | location = Edinburgh | isbn = 0-550-10105-5 | url-access = registration | url = https://archive.org/details/chambersdictiona0000unse_x2v6 |page=1510}}.</ref> Behaviour and [[Morphology (biology)|morphology]] suggest that the terns are more closely related to the gulls than to the skimmers or skuas, and although [[Charles Lucien Bonaparte]] created the family Sternidae for the terns in 1838, for many years they were considered to be a subfamily, Sterninae, of the gull family, Laridae. Relationships between various tern species, and between the terns and the other Charadriiformes, were formerly difficult to resolve because of a poor [[fossil]] record and the misidentification of some finds.<ref name= HBW>Gochfeld & Burger (1996) pp. 624–645.</ref><ref name= pietri>{{cite journal |last= de Pietri |first= Vanesa L | author2=Costeur, Loïc| author3=Güntert, Marcel| author4=Mayr, Gerald |year=2011 |title= A revision of the Lari (Aves, Charadriiformes) from the early Miocene of Saint-Gérand-le-Puy (Allier, France) | journal= Journal of Vertebrate Paleontology | volume=31 | pages=812–828 |doi=10.1080/02724634.2011.586663|issue= 4|bibcode= 2011JVPal..31..812D |s2cid= 84758271 }}</ref>

Following [[gene]]tic research in the early twenty-first century, the terns were historically treated as a separate family, Sternidae.<ref name = paton>{{cite journal | last1 = Paton | first1 = Tara A | last2 = Baker | first2 = Allan J | year = 2006 | title = Sequences from 14 mitochondrial genes provide a well-supported phylogeny of the Charadriiform birds congruent with the nuclear RAG-1 tree | journal = Molecular Phylogenetics and Evolution | volume = 39 | issue = 3| pages = 657–667 | doi = 10.1016/j.ympev.2006.01.011 | pmid = 16531074 | bibcode = 2006MolPE..39..657P }}</ref><ref>{{cite journal | last1 = Thomas | first1 = Gavin H | last2 = Wills | first2 = Matthew A | last3 = Székely | first3 = Tamás | year = 2004 | title = A supertree approach to shorebird phylogeny | journal = [[BMC Evolutionary Biology]] | volume = 4 |page = 28 | doi = 10.1186/1471-2148-4-28 | pmid = 15329156 | pmc=515296 | doi-access = free }}</ref> Most terns were formerly treated as belonging to one large genus, ''[[Sterna]]'', with just a few dark species placed in other genera; in one 1959 paper, only the [[Noddy (tern)|noddies]] and the [[Inca tern]] were excluded from ''Sterna''.<ref name=" Moynihan" >{{cite journal | last= Moynihan | first= M | year= 1959 | title= A revision of the family Laridae | journal= American Museum Novitates | issue= 1928 |pages= 1–42 }}</ref><ref name= collinson>{{cite journal | last= Collinson | first= M | year= 2006 | title= Splitting headaches? Recent taxonomic changes affecting the British and Western Palaearctic lists | journal= [[British Birds (magazine)|British Birds]] | volume= 99 | issue= 6 | pages= 306–323 | url= https://britishbirds.co.uk/wp-content/uploads/article_files/V99/V99_N06/V99_N06_P306_323_A004.pdf | access-date= 17 April 2017 | archive-date= 8 August 2020 | archive-url= https://web.archive.org/web/20200808071132/https://britishbirds.co.uk/wp-content/uploads/article_files/V99/V99_N06/V99_N06_P306_323_A004.pdf | url-status= dead }}</ref> A recent analysis of [[Nucleic acid sequence|DNA sequences]] supported the splitting of ''Sterna'' into several smaller genera.<ref name= collinson/><ref name= bridge>{{cite journal | last= Bridge |first= Eli S | author2= Jones, Andrew W| author3=Baker, Allan J | year= 2005 | title= A phylogenetic framework for the terns (Sternini) inferred from mtDNA sequences: implications for taxonomy and plumage evolution | journal= Molecular Phylogenetics and Evolution | volume= 35 |issue= 2 | pages= 459–469 | doi = 10.1016/j.ympev.2004.12.010 | pmid=15804415|bibcode= 2005MolPE..35..459B |s2cid= 25027599 }}</ref> One study of part of the [[cytochrome b]] gene sequence found a close relationship between terns and a group of waders in the suborder [[Thinocori]].<ref name= thomas>{{cite journal | last= Thomas | first= Gavin H | author2=Wills, Matthew A| author3=Székely, Tamás | year= 2004 | title= Phylogeny of shorebirds, gulls, and alcids (Aves: Charadrii) from the cytochrome-''b'' gene: parsimony, Bayesian inference, minimum evolution, and quartet puzzling | journal= Molecular Phylogenetics and Evolution | volume= 30 | issue = 3 | pages= 521–526 | doi = 10.1016/S1055-7903(03)00222-7 | pmid=15012936| bibcode= 2004MolPE..30..516T }}</ref> These results are in disagreement with other molecular and morphological studies, and have been interpreted as showing either a large degree of molecular [[convergent evolution]] between the terns and these waders, or the retention of an ancient [[genotype]].<ref name= paton/>

Research in 2007 had suggested that the noddies were not terns at all, but were basal to all the other genera in Laridae,<ref name="Baker">{{cite journal |last1=Baker |first1=Allan J. |last2=Pereira |first2=Sérgio L. |last3=Paton |first3=Tara A. |title=Phylogenetic relationships and divergence times of Charadriiformes genera: multigene evidence for the Cretaceous origin of at least 14 clades of shorebirds |journal=Biology Letters |date=2007 |volume=3 |issue=2 |pages=205–209 |doi=10.1098/rsbl.2006.0606 |pmid=17284401 |pmc=2375939 }}</ref> a taxonomy that was followed by the IOC World Bird List for several years up to 2023, but more comprehensive analysis has now shown that the noddies are basal to only the other terns, not the whole family;<ref name="Cerny"/> this has now been followed by the IOC World Bird List version 14.1 in 2024.

===Etymology===
The word "stearn" was used for these birds in [[Old English]] as early as the eighth century, and appears in the poem ''[[The Seafarer (poem)|The Seafarer]]'', written in the ninth century or earlier. Variants such as "tearn" occurred by the eleventh century, although the older form lingered on in [[Norfolk dialect]] for several centuries.<ref name = hume12>Hume (1993) pp. 12–13.</ref> As now, the term was used for the inland [[black tern]] as well as the marine species.<ref name= job365>Jobling (2010) p. 365.</ref><ref name= lock>Lockwood (1984) pp. 147, 153.</ref> Some authorities consider "tearn" and similar forms to be variants of "stearn",<ref name = hume12/> while others derive the English words from Scandinavian equivalents such as Danish and Norwegian ''terne'' or Swedish ''tärna'', and ultimately from [[Old Norse]] ''þerna''.<ref name=OED1>{{Cite OED |Tern}}</ref><ref>Merriam-Webster (2014)</ref> Linnaeus adopted "stearn" or "sterna" (which the naturalist [[William Turner (naturalist)|William Turner]] had used in 1544 as a Latinisation of an English word, presumably "stern", for the black tern)<ref name=OED2>{{Cite OED |Sterna}}</ref><ref name=Turner78>Turner (1544), p. 78.</ref> or a [[North Germanic languages|North Germanic]] equivalent for his genus name ''Sterna''.<ref name = linn155>Linnaeus (1758) p. 155.</ref> All of these names are ultimately [[onomatopoea|onomatopoeic]], derived from the bird's calls.<ref name= lock/>

=== Species ===
The [[cladogram]] shows the relationships between the tern genera, and the currently recognised species, based on [[mitochondrial DNA]] studies, are listed below:<ref name= bridge/>
{{Cladogram|caption=Based on Bridge ''et al'' (2005)<ref name= bridge/> and Černý & Natale (2021)<ref name="Cerny"/>
|clades={{clade|style=font-size:80%;line-height:80%
   |1={{clade
      |1= ''[[Anous]]''
      |2={{clade
         |1=''[[Gygis]]''
         |2={{clade
            |1=''[[Onychoprion]]''
            |2={{clade
               |1=''[[Sternula]]''
               |2={{clade
                  |1=''[[Phaetusa]]''
                  |2={{clade
                     |1={{clade
                        |1=''[[Gelochelidon]]''
                        |2=''[[Hydroprogne]]''
                        }}
                     |2={{clade
                        |1=''[[Larosterna]]''
                        |2={{clade
                           |1=''[[Chlidonias]]''
                           |2={{clade
                              |1=''[[Thalasseus]]''
                              |2=''[[Sterna]]''
                              }}
                           }}
                        }}
                     }}
                  }}
               }}
            }}
         }}
      }}
   }}
}}

{| class="wikitable collapsible"
|-
! Image
! Genus
!Species
|-
|[[File:Anous minutus by Gregg Yan 02.jpg|175px]]
|''[[Anous]]'' {{small|Stephens, 1826}} — [[Noddy (tern)|noddies]]
|
* [[Brown noddy]] (''Anous stolidus'')
* [[Black noddy]] (''A. minutus''; sometimes considered to be a subspecies of the lesser noddy)<ref name= harrison388/>
* [[Lesser noddy]] (''A. tenuirostris'')
* [[Blue noddy]] (''A. cerulea''; formerly placed in a separate genus ''Procelsterna'')<ref name= harrison388/>
* [[Grey noddy]] (''A. albivitta''; sometimes considered to be a subspecies of the blue noddy; formerly placed in a separate genus ''Procelsterna'')<ref name= harrison388/>
|-
|[[File:White tern with fish.jpg|175px]]
|''[[Gygis]]'' {{small|Wagler, 1832}} — noddies
|
* [[White tern]] (''Gygis alba'' also sometimes called white noddy)
|-
|[[File:Sterna fuscata.JPG|175px]]
|''[[Onychoprion]]'' {{small|Wagler, 1832}} — brown-backed terns
|
* [[Spectacled tern]] (''Onychoprion lunatus'')
* [[Bridled tern]] (''O. anaethetus'')
* [[Sooty tern]] (''O. fuscatus'')
* [[Aleutian tern]] (''O. aleuticus'')
|-
|[[File:Yellow-billed tern Sternula superciliaris.jpg|175px]]
|''[[Sternula]]'' {{small|F. Boie, 1822}} — little white terns
|
* [[Fairy tern]] (''Sternula nereis'')
* [[Damara tern]] (''S. balaenarum'')
* [[Little tern]] (''S. albifrons'')
* [[Saunders's tern]] (''S. saundersi'' formerly considered to be a subspecies of the little tern)<ref name= harrison382>Harrison (1988) p. 382.</ref>
* [[Least tern]] (''S. antillarum'' formerly considered to be a subspecies of the little tern)<ref name= harrison382/>
* [[Yellow-billed tern]] (''S. superciliaris'')
* [[Peruvian tern]] (''S. lorata'')
|-
|[[File:Large-billed Tern (Phaetusa simplex), Pantanal, Brazil.jpg|175px]]
|''[[Phaetusa]]'' {{small|}}  — large-billed terns
|
* [[Large-billed tern]] (''Phaetusa simplex'')
|-
|[[File:Sterna-caspia-010.jpg|175px]]
|''[[Hydroprogne]]'' {{small|Kaup, 1829}}— Caspian terns
|
* [[Caspian tern]] (''Hydroprogne caspia'')
|-
|[[File:Gull-billed Tern in Koonthalulam, India, by Dr. Tejinder Singh Rawal.jpg|175px]]
|''[[Gelochelidon]]''  {{small|Brehm, 1830}} — gull-billed terns
|
* [[Gull-billed tern]] (''Gelochelidon nilotica'')
* [[Australian tern]] (''Gelochelidon macrotarsa'')

|-
|[[File:Larosterna inca3.jpg|175px]]
|''[[Larosterna]]'' {{small|}} — Inca terns
|
* [[Inca tern]] (''Larosterna inca'')
|-
|[[File:White-winged Tern, Mścichy, Biebrzański Park Narodowy, Polska.jpg|175px]]
|''[[marsh tern|Chlidonias]]'' {{small|Rafinesque, 1822}}  — marsh terns
|
* [[Black tern]] (''Chlidonias niger'')
* [[White-winged tern]] (or white-winged black tern ''C. leucopterus'')
* [[Whiskered tern]] (''C. hybridus'')
* [[Black-fronted tern]] (''C. albostriatus'' sometimes placed in ''Sterna'')<ref name = birdlifealbostriata/>
|-
|[[File:2020-07-18 Thalasseus sandvicensis, St Marys Island, Northumberland 01.jpg|175px]]
|''[[Thalasseus]]'' {{small|F. Boie, 1822}} — crested terns
|
* [[Lesser crested tern]] (''Thalasseus bengalensis'')
* [[West African crested tern]] (''Thalasseus albididorsalis'' recently split from ''T. maximus'')<ref name= collinson/>
* [[Royal tern]] (''T. maximus'')
* [[Greater crested tern]] (''T. bergii'' also known as swift tern)
* [[Chinese crested tern]] (''T. bernsteini'')
* [[Elegant tern]] (''T. elegans'')
* [[Sandwich tern]] (''T. sandvicensis'')
* [[Cabot's tern]] (''T. acuflavidus'' recently split from ''T. sandvicensis'')<ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | year=2019 | title=Sandpipers, snipes, coursers | work=World Bird List Version 9.2 | url=https://www.worldbirdnames.org/bow/sandpipers/ | publisher=International Ornithologists' Union | access-date=25 June 2019 }}</ref>

|-
|[[File:2014-05-18 Sterna hirundo, Killingworth Lake, Northumberland 02.jpg|175px]]
|''[[Sterna]]'' {{small|Linnaeus, 1758}} — large white terns
|
* [[Forster's tern]] (''Sterna forsteri'')
* [[Snowy-crowned tern]] (''S. trudeaui'')
* [[Common tern]] (''S. hirundo'')
* [[Roseate tern]] (''S. dougallii'')
* [[White-fronted tern]] (''S. striata'')
* [[Black-naped tern]] (''S. sumatrana'')
* [[South American tern]] (''S. hirundinacea'')
* [[Antarctic tern]] (''S. vittata'')
* [[Kerguelen tern]] (''S. virgata'')
* [[Arctic tern]] (''S. paradisaea'')
* [[River tern]] (''S. aurantia'')
* [[Black-bellied tern]] (''S. acuticauda'' possibly ''Chlidonias'')<ref name= bridge/>
* [[White-cheeked tern]] (''S. repressa'' possibly ''Chlidonias'')<ref name= bridge/>
|-
|}

In addition to extant species, the fossil record includes a [[Miocene]] [[chronospecies|palaeospecies]], ''[[Sterna milne-edwardsii]]''.<ref name = fossil>{{cite web | title= Fossil record of the Charadriiformes | url= http://palaeo.gly.bris.ac.uk/Palaeofiles/Fossilgroups/charadriformes/fossils.html | publisher= Palaeobiology and Biodiversity Research Group, University of Bristol | access-date= 13 May 2013 | archive-url= https://web.archive.org/web/20160304023443/http://palaeo.gly.bris.ac.uk/Palaeofiles/Fossilgroups/charadriformes/fossils.html | archive-date= 4 March 2016 | url-status= dead | df= dmy-all }}</ref>

The birds in the genus ''[[Anous]]'' are known as noddies, the ''[[Chlidonias]]'' species are the marsh terns,<ref name =HBW/> and all other species comprise the sea terns.<ref name= Barlow>Barlow ''et al.'' (1987) p. 212.</ref><ref name= perrins>Perrins & Arlott (1987) p. 130.</ref>