Gruae

Gruae^[3] is a clade of birds that contains the order Opisthocomiformes (hoatzin) and Gruimorphae (shorebirds and rails) identified in 2014 by genome analysis.^[4] Previous studies have placed the Hoatzin in different parts of the bird family tree; however, despite its unusual and primitive morphology, genetic studies have shown the hoatzin is not as primitive or as ancient as once thought, and that it could be a very derived bird that reverted to or retains some plesiomorphic traits.^[4][5][6]

Gruae	Opisthocomiformes (hoatzin) Gruimorphae Gruiformes (rails and cranes) Charadriiformes (shorebirds)

Gruae Temporal range: Paleocene[1] [2] - Holocene, 60–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Hoatzin (Opisthocomus hoazin)
African swamphen (Porphyrio madagascariensis)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Infraclass:	Neognathae
Clade:	Neoaves
(unranked):	Passerea
(unranked):	Gruae Bonaparte, 1854
Subgroups
Opisthocomiformes Gruimorphae

According to Suh et al. (2016), one of the problems with the conclusions about this novel clade is that independent studies (like Jarvis et al. 2014 and Prum et al. 2015)^[7][4] found very dissimilar phylogenetic relationships (like Inopinaves) using the same probabilistic support, such as bootstrap scores and Bayesian posterior probabilities.^[8]

See also

• Inopinaves for an alternative hypothesis on the placement of the Hoatzin

References

1. Mourer-Chaviré C. (1995) The Messelornithidae (Aves: Gruiformes) from the Paleogene of France. - Cour. Forsch.-Inst. Senckenberg, 181: 95-105
2. Mayr, Gerald (2016). Avian evolution: the fossil record of birds and its paleobiological significance. Topics in Paleobiology. Wiley-Blackwell. p. 306. ISBN 978-1-119-02076-9.
3. "TiF Checklist: GRUAE I: Opisthocomiformes & Gruiformes".
4. Jarvis, E.D. et al. (2014) Whole-genome analyses resolve early branches in the tree of life of modern birds. Science, 346(6215):1320-1331.
5. Fain, Matthew G. & Houde, Peter (2004). "Parallel radiations in the primary clades of birds" (PDF). Evolution. 58 (11): 2558–2573. doi:10.1554/04-235. PMID 15612298. S2CID 1296408. Archived from the original (PDF) on 2013-04-07.
6. Hackett, S.J. et al. (2008) A Phylogenomic Study of Birds Reveals Their Evolutionary History. Science, 320(5884):1763–1768.
7. Prum, R. O. et al. A comprehensive phylogeny of birds (Aves) using targeted next-generation DNA sequencing. Nature (2015). doi:10.1038/nature15697
8. Suh, A. (2016) The phylogenomic forest of bird trees contains a hard polytomy at the root of Neoaves, Zool. Scripta 45(S1), 50-62.