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Suliformes

Order of birds

Wikipedia contributorsAdapted for Fathomly · View authors
3 min read
Source updated April 14, 2026
Image credit is listed at the end of this article.

The order Suliformes (/ˈsjuːlɪfɔːrmiːz/, dubbed "Phalacrocoraciformes" by Christidis & Boles 2008) is an order of birds that includes gannets, boobies, frigatebirds, cormorants and darters. The order is recognised by the International Ornithologist's Union. Regarding the recent evidence that the traditional Pelecaniformes is polyphyletic, it has been suggested that the group be divided to reflect the true evolutionary relationships; a 2017 study indicated that they are most closely related to Otidiformes (bustards) and Ciconiiformes (storks).

01Systematics and evolution

Of the families in Pelecaniformes, only Pelecanidae, Balaenicipitidae, and Scopidae remain. The tropicbird family Phaethontidae has since been moved to their order Phaethontiformes. Genetic analysis seems to show that the Pelecaniformes are actually closely related to the Ardeidae and Threskiornithidae. As for the Suliformes, they are distantly related to the current Pelecaniformes. According to Hackett et al. (2008), loons, penguins, storks, and as well as Suliformes and Pelecaniformes, all seem to have evolved from a common ancestor. The proposed waterbird superorder has been suggested.

In their landmark 2008 work Systematics and Taxonomy of Australian Birds, Australian ornithologists Les Christidis and Walter E. Boles coined the name Phalacrocoraciformes for the group due to the much greater number of species of cormorants (Phalacrocoracidae) over boobies and gannets (Sulidae). However, this has not been taken up elsewhere.

In 1994, American ornithologist Walter J. Bock wrote that the name Suloidea had been used consistently as a term for a superfamily containing the two families, so therefore "Sulidae" and not "Phalacrocoracidae" should take priority in any arrangement containing the two genera.

In 2010, the AOU adopted the term Suliformes for the taxon. The IOC followed in 2011.

In 1994, Martyn Kennedy and colleagues constructed a behavioural data set, with the resulting tree showing a high level of congruence with existing phylogenies based on genetics or morphology. It showed the darters as sister group to the cormorants and shags, with the gannets and boobies, then pelicans, then frigatebirds and lastly tropicbirds as progressively earlier offshoots.

Suliformes

Fregatidae

Sulidae

Anhingidae

Phalacrocoracidae

Cladogram based on Gibb, G.C. et al. (2013)

Bones of the left foot of Fregata aquila showing pectinate edge to mid claw, a characteristic of the Suliformes.
Bones of the left foot of Fregata aquila showing pectinate edge to mid claw, a characteristic of the Suliformes.

02Species

Little cormorant Microcarbo niger
Little cormorant Microcarbo niger
Watch videos about SuliformesExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article “Suliformes”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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