Belongs within: Columbaves.
The Musophagidae, turacos, are an African family of colourful, fruit-eating birds with stubby bills, long tails, a reversible outer toe and often a pronounced crest.
Banana-eating birds that don’t eat bananas
Published 14 April 2008
I’m going to take a closer look at the Musophagidae, a uniquely African family of birds that contains the turacos (or should that be “turacoes”?), also spelt “touracos”. Turacos are about 20 species of medium-sized frugivorous (fruit-eating) birds. The name of the type genus, Musophaga, means “plantain eater”, which is also used as the vernacular name for some of the largest species, though it seems that they rarely, if ever, actually eat plantains (plantains, for those not in the know, are bananas eaten baked when they are still fairly green and contain more starch). Figs seem to a much more favoured food. Rutgers & Norris (1972) mentions them also feeding on leaves, insects and occassionally even meat, though it is unclear whether turacos actually eat the latter in the wild.
Turacos are best known for their brilliant coloration, and not without reason. The red turacin and the green turacoverdin are unique among bird pigments in being metal-bearing porphyrins, the same class of compounds as the heme found in haemoglobin, though the turaco pigments contain copper rather than iron. Turacin is unique to turacos, while there is evidence that turacoverdin (or a very similar compound) is also found in the Jacana spinosa, the blood pheasant Ithaginis cruentata and the roulroul Rollolus roulroul, a species of partridge (Dyck 1992). Turacoverdin (and the pigments in the latter three species, if they are distinct) is also notable as the only truly green pigment known from any bird. Green coloration in other birds is the result of structural coloration (from the crystalline structure of the feathers), or the combination of yellow pigment and blue structural coloration (Hill & McGraw 2006). Rutgers and Norris (1972) mention a persistent belief that turacin is water-soluble, and actually washes out when the bird bathes. While this belief is untrue, turacin is soluble in more alkali solutions.
Turacin and turacoverdin are found in four of the six or seven genera of turacos. The genera Crinifer and Corythaixoides (together forming the subfamily Criniferinae) lack both pigments and are mostly grey. Species of Corythaixoides are also known as “go-away birds” after the sound of their calls. These two genera, as well as the great blue turaco (Corythaeola cristata) which is placed in its own subfamily, are referred to as the grey turacos. Corythaeola is also mostly grey, but does have small patches of turacin (the vent) and turacoverdin (a small breast-stripe). The remaining turacos, referred to as the turacin-bearing turacos, are included in the subfamily Musophaginae (Veron & Winney, 2000). Over half the species of turaco belong to the genus Tauraco, which are mostly a spectacular green. Tauraco, the purple-crested turaco (Gallirex porphyreolophus)* and the Ruwenzori turaco (Ruwenzorornis johnstoni) contain both turacin and turacoverdin (the latter two species may be included in the genus Musophaga). The remaining species of Musophaga in the strict sense lack turacoverdin and are a brilliant blue colour, with bright red crests coloured with turacin.
*Gallirex is a very neat genus name—it means “king of the chickens”.
The relationships of the turacos to other birds have long been problematic. The most common position attributed to them has been as sister taxon to the cuckoos (Cuculidae), but other suggested relationships have been with the Galliformes or Opisthocomus (the hoatzin). The morphological analysis of Livezey and Zusi (2007) supported the traditional position, while the molecular analysis of Ericson et al. (2006) placed both Musophagidae and Cuculidae in a grade of largely terrestrial birds, also including the Grues (cranes and rails) and Otididae (bustards), sitting at the base of the mostly aquatic “higher waterbird” clade, but was unresolved to whether the two families formed a monophyletic group.
Systematics of Musophagidae
Musophagidae [Criniferidae, Musophagi, Musophagiformes]
|--+--Corythaeola Heine 1860BKB15, B94 [Corythaeolidae]
| | `--C. cristata (Vieillot 1816) [=Musophaga cristata]M-PG70
| | |--C. c. cristataRN72
| | `--C. c. yalersisRN72
| `--CorythaixoidesBKB15
| |--C. concolor (Smith 1833)BKB15 [=Corythaix concolorM-PG70, Crinifer (Corythaixoides) concolorRN72]
| | |--C. c. concolorM-PG70
| | `--C. c. pallidiceps Neumann 1899M-PG70
| `--+--C. personatusBKB15 [=Crinifer (Corythaixoides) personataRN72]
| `--+--C. leucogaster (Rüppell 1842)BKB15, ME04 [=Crinifer (Corythaixoides) leucogasterRN72]
| `--Crinifer Jarocki 1821BKB15, B94
| |--C. africanusRN72
| |--C. piscator (Boddaert 1783) [=Falco piscator; incl. C. piscator obscuratus Grote 1923]M-PG70
| `--C. zonurus (Rüppell 1835)BKB15, S05 [=Chizaerhis zonurusS05, Cr. africanus zonurusS05]
`--+--Ruwenzorornis johnstoni (Sharpe 1901)BKB15, M-PG70 [=Gallirex johnstoniM-PG70]
| |--R. j. johnstoniRN72
| |--R. j. bredoi Verheyen 1947M-PG70
| `--R. j. kivuensis Neumann 1908RN72
`--Tauraco Kluk 1779BKB15, B94 [incl. Turacus Cuvier 1800B94; Tauracidae, Turacidae]
| i. s.: T. persa (Linnaeus 1758) [=Cuculus persa]M-PG70
| |--T. p. persaM-PG70
| |--T. p. buffoni (Vieillot 1819)M-PG70 [=Opaethus buffoniM-PG70, Turacus buffoniP13]
| `--T. p. zenkeri (Reichenow 1896) [=Turacus zenkeri]M-PG70
| T. ruspoliiJT12
|--T. leucotis (Rüppell 1835)BKB15, S05 [=Corythaix leucotisS05]
| |--T. l. leucotisRN72
| `--T. l. donaldsoniRN72
`--+--+--+--T. corythaixBKB15
| | | |--T. c. corythaixRN72
| | | |--T. c. phoebusRN72
| | | `--T. c. reichenowiRN72
| | `--+--T. fischeriBKB15
| | `--T. livingstoniiBKB15
| `--+--T. schuettii (Cabanis 1879)JT12, M-PG70 [=Corythaix schuettiiM-PG70; incl. T. schuettii finschiM-PG70]
| | |--T. s. schuettiiM-PG70
| | |--T. s. emini (Reichenow 1893) [=Turacus emini]M-PG70
| | `--T. s. sharpei (Reichenow 1898) [=Turacus sharpei]M-PG70
| `--+--T. hartlaubiBKB15
| `--T. schalowi (Reichenow 1891)BKB15, M-PG70 [=Corythaix schalowiM-PG70, T. livingstonii schalowiRN72]
| |--T. s. schalowiM-PG70
| `--T. s. marungensis (Reichenow 1902) [=Turacus livingstonii marungensis]M-PG70
`--+--+--T. porphyreolophusBKB15
| `--+--T. bannermaniBKB15
| `--+--T. erythrolophus (Vieillot 1819)BKB15, M-PG70 [=Opaethus erythrolophusM-PG70]
| `--T. leucolophus (Heuglin 1855)BKB15, M-PG70 [=Corythaix leucolophusM-PG70]
`--+--T. macrorhynchus (Fraser 1839)BKB15, M-PG70 [=Corythaix macrorhynchaM-PG70]
| |--T. m. macrorhynchusM-PG70
| `--T. m. verreauxi (Schlegel 1854) [=Musophaga verreauxi]M-PG70
`--Musophaga Isert 1789BKB15, B94
|--M. rossae Gould 1851M-PG70 (see below for synonymy)
`--M. violacea Isert 1789M-PG70
Musophagidae incertae sedis:
Gallirex porphyreolophusRN72
|--G. p. porphyreolophusRN72
`--G. p. chlorochlamysRN72
ChizaerhisR42
|--C. leucogaster Rüppell 1842R42
`--C. personata Rüppell 1842R42
Proturacus bannermani Bates 1923M-PG70
Gymnoschizorhis personataM-PG70
|--G. p. personataM-PG70
`--G. p. centralis Neumann 1908M-PG70
Musophaga rossae Gould 1851M-PG70 [=M. violacea rossaeRN72; incl. M. rossae savannicolaM-PG70, M. violacea savannicolaRN72]
*Type species of generic name indicated
References
[B94] Bock, W. J. 1994. History and nomenclature of avian family-group names. Bulletin of the American Museum of Natural History 222: 1–281.
[BKB15] Burleigh, J. G., R. T. Kimball & E. L. Braun. 2015. Building the avian tree of life using a large-scale, sparse supermatrix. Molecular Phylogenetics and Evolution 84: 53–63.
Dyck, J. 1992. Reflectance spectra of plumage areas colored by green feather pigments. The Auk 109 (2): 293–301.
Ericson, P. G. P., C. L. Anderson, T. Britton, A. Elzanowski, U. S. Johansson, M. Källersjö, J. I. Ohlson, T. J. Parsons, D. Zuccon & G. Mayr. 2006. Diversification of Neoaves: integration of molecular sequence data and fossils. Biology Letters 2 (4): 543–547.
Hill, G. E., & K. J. McGraw. 2006. Bird Coloration. Harvard University Press.
[JT12] Jetz, W., G. H. Thomas, J. B. Joy, K. Hartmann & A. Ø. Mooers. 2012. The global diversity of birds in space and time. Nature 491: 444–448.
Livezey, B. C., & R. L. Zusi. 2007. Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion. Zoological Journal of the Linnean Society 149 (1): 1–95.
[M-PG70] Mackworth-Praed, C. W., & C. H. B. Grant. 1970. African Handbook of Birds ser. 3 vol. 1. Birds of West Central and Western Africa. Longman: London.
[ME04] Mayr, G., & P. G. P. Ericson. 2004. Evidence for a sister group relationship between the Madagascan mesites (Mesitornithidae) and the cuckoos (Cuculidae). Senckenbergiana Biologica 84 (1–2): 1–17.
[P13] Porta, A. 1913. Acantocefali della Nuova Caledonia e delle isole Loyalty. In: Sarasin, F., & J. Roux (eds) Nova Caledonia: Forschungen in Neu-Caledonian und auf den Loyalty-Inseln. A. Zoologie vol. 1 pt 3 pp. 167–170. C. W. Kreidels Verlag: Wiesbaden.
[R42] Rüppell, E. 1842. On two new species of Chizaerhis from Abyssinia. Proceedings of the Zoological Society of London 10: 8–9.
[RN72] Rutgers, A., & K. A. Norris (eds.) 1972. Encyclopaedia of Aviculture vol. 2. Blandford Press: London.
[S05] Steinheimer, F. D. 2005. Eduard Rüppel’s avian types at the Natural History Museum, Tring (Aves). Senckenbergiana Biologica 85 (2): 233–264.
Veron, G., & B. J. Winney. 2000. Phylogenetic relationships within the turacos (Musophagidae). Ibis 142 (3): 446–456.