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Neoaves

(Infraclass)

Overview

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Neognaths (Neognathae) are within the subclass Neornithes of the class Aves. The Neognathae include virtually all living birds; their sister taxon Palaeognathae contains the tinamous - their only order capable of flight - as well as the flightless ratites.

There are nearly 10,000 species of neognaths. Since the late Cretaceous from where the earliest fossils are known, they have undergone adaptive radiation to produce the staggering diversity of form (especially of the bill and feet), function, and behavior that we see today. The Passeriformes (perching birds) are the largest order of land vertebrates, containing some 60% of living birds and being more than twice as diverse as rodents and about 5 times as diverse as Chiroptera (bats and flying foxes) which are the largest order of mammals. On the other hand, there are some very small orders, usually birds of very unclear relationships like the puzzling Hoatzin.

The neognaths have fused metacarpals, an elongate third finger, and 13 or fewer vertebrae. They differ from the Palaeognathae in features like the structure of their jawsbones. "Neognathae" means "new jaws", but ironically it seems that the supposedly "more ancient" paleognath jaws are among the few apomorphic ("more advanced") features of this group as compared to the neognaths.

Taxonomy and Systematics

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The Great Crested Grebe (Podiceps cristatus), despite its looks, belongs to the closest living relatives o f flamingos.

For long the Neognathae were ranked as a superorder and not subdivided any further; attempts to do so, for example in the Conspectus of Charles Lucien Bonaparte, were never accepted even by a significant majority of ornithologists. Indeed, until the 1980s there was little subdivision of the Aves in general, and even less of phylogenetic merit. Since then the availability of massive amounts of new data from fossils - especially Enantiornithes and other Mesozoic birds - as well as molecular (DNA and protein) sequences allowed scientists to refine the classification. With new groups of neognath orders being verified, the taxonomic rank of the group needed to shift. In fact, most researchers have by now employed the unranked taxa of phylogenetic nomenclature.[1]

Domestic chicken belong to the fowl clade, Galloanserae.
Pacific Golden Plover (Pluvialis fulva), part of the diverse and ancient Charadriiformes.
Black Kites (Milvus migrans) like other accipitrids have peculiar chromosomes. This has much confounded molecular phylogeny.
Male Red Bird of Paradise (Paradisaea rubra) - a spectacular passerine.
Cladogram showing an alternative classification of Neoaves, based on recent phylogenetic studies.

The Neognathae are universally accepted to subdivide into two lineages - the "fowl" clade Galloanseres and the Neoaves (sometimes called "higher neognaths"). The subdivisions of the latter are still not well resolved, but several monophyletic lineages have been proposed, such as the Mirandornithes, Cypselomorphae or Metaves and Coronaves. While groups such as the former two - uniting a few closely-related orders - are robustly supported, this cannot be said for the Metaves-Coronaves division for which there is no material evidence at present while the Mesozoic record of Neognathae is at present utterly devoid of birds that would have to be present if these proposed clades were real.[2]

Taxonomic note:
The ranks used here are rarely employed in the literature. The ultimate reason is a limitation in the Wikipedia taxobox code, which does not allow for an arbitrary number of "unranked" taxa to be displayed. As the taxa used here have all been validly described and neither the ICZN nor any other authority regulates their employment, the present ranking is as valid as any other - perhaps even more - and given the technical limitations the only system that can currently be used within the scope of Wikipedia. More commonly found is the old placement as a superorder - but such systematic treatments need to be viewed with caution, as they often do not even incorporate the Galloanserae - or as unranked clade.

Systematics

The orders are arranged in a sequence that attempts to follow the modern view on neognath phylogeny. It differs from the widely-used Clements taxonomy as well as from the Sibley-Ahlquist taxonomy, combining those elements from each that more modern research agrees with while updating those that are refuted. The result is at least a much better representation of the true evolutionary relationships of neognath orders. Most of the changes affect those "higher landbirds" that are sometimes united as near passerines.[3]


Photos

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Taxonomy

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The Infraclass Neoaves is a member of the Subclass Neornithes. Here is the complete "parentage" of Neoaves:

The Infraclass Neoaves is further organized into finer groupings including:

Orders

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Anseriformes

The order Anseriformes contains about 150 living of birds in three extant families: the Anhimidae (the screamers), Anseranatidae (the Magpie-goose), and the Anatidae, which includes over 140 species of waterfowl, among them the ducks, geese, and swans. [more]

Apodiformes

Traditionally, the order Apodiformes contained three living families: the swifts, Apodidae, the tree swifts, Hemiprocnidae, and the hummingbirds, Trochilidae. In the Sibley-Ahlquist taxonomy, this order is raised to a superorder Apodimorphae in which hummingbirds are separated as a new order, Trochiliformes, but this has been refuted by subsequent research. With nearly 450 species identified to date, they are the most diverse order of birds after the passerines. [more]

Bucerotiformes

Hornbills (Bucerotidae) are a of bird found in tropical and sub-tropical Africa and Asia. They are characterized by a long, down-curved bill which is frequently brightly-colored and sometimes has a casque on the upper mandible. Both the common English and the scientific name of the family refer to the shape of the bill, "buceros" being "cow horn" in Greek. In addition, they possess a two-lobed kidney. Hornbills are the only birds in which the first two neck vertebrae (the axis and atlas) are fused together; this probably provides a more stable platform for carrying the bill. The family is omnivorous, feeding on fruit and small animals. They are monogamous breeders nesting in natural cavities in trees and sometimes cliffs. A number of species of hornbill are threatened with extinction, mostly insular species with small ranges. [more]

Ciconiiformes

Traditionally, the Ciconiiformes has included a variety of large, long-legged wading birds with large bills: storks, herons, egrets, ibises, spoonbills, and several others. Ciconiiformes are known from the Late Eocene. At present the only family retained in the order is the storks, Ciconiidae. [more]

Coliiformes

The mousebirds are a small group of (possibly ) birds which have no real close affinities to other groups, though they and the parrots and cockatoos (Psittaciformes) may be closer to each other than to other birds. The mousebirds are therefore given order status as Coliiformes. This group is confined to sub-Saharan Africa, and is the only bird order confined entirely to that continent. They had a wider range in prehistoric times and apparently evolved in Europe. [more]

Columbiformes

The order Columbiformes includes the very widespread and successful doves and pigeons, classified in the family Columbidae, and the extinct Dodo and the Rodrigues Solitaire, long classified as a second family Raphidae. 313 species, found worldwide, comprise the Columbiformes order. Like many birds, all Columbiformes are monogamous. Unlike most other birds, however, they are capable of drinking by sucking up water, without needing to tilt the head back. [more]

Coraciiformes

The Coraciiformes are a group of usually colorful birds including the kingfishers, the Hoopoe, the bee-eaters, the rollers, and the hornbills. They generally have syndactyly, with three forward-pointing toes (and toes 3 & 4 fused at their base), though in many kingfishers one of these is missing. [more]

Craciformes

Galliformes are an of birds containing turkeys, grouse, chickens, quails, and pheasants. More than 250 living species are found worldwide. Common names are gamefowl or gamebirds, landfowl, gallinaceous birds or galliforms. "Wildfowl" or just "fowl" are also often used for Galliformes, but usually these terms also refer to waterfowl, and occasionally to other commonly-hunted birds. [more]

Cuculiformes

The bird order Cuculiformes traditionally included three families as below: [more]

Diatrymiformes

[more]

Galbuliformes

An of birds comprising the jacamar and puffbird families, Galbulidae and Bucconidae. there are 51 species ranging from Mexico to tropical South America. [more]

Galliformes

Galliformes are an of birds containing turkeys, grouse, chickens, quails, and pheasants. More than 250 living species are found worldwide. Common names are gamefowl or gamebirds, landfowl, gallinaceous birds or galliforms. "Wildfowl" or just "fowl" are also often used for Galliformes, but usually these terms also refer to waterfowl, and occasionally to other commonly-hunted birds. [more]

Gruiformes

The polyphyletic Gruiformes contains a considerable number of living and extinct bird families with little in common. They are morphologically diverse and geographically widespread. Gruiform means "crane-like." [more]

Musophagiformes

The turacos make up the family Musophagidae (literally "banana-eaters"), which includes plantain-eaters and go-away-birds. In southern Africa both turacos and go-away-birds are commonly known as louries. They are semi-zygodactylous - the fourth (outer) toe can be switched back and forth. The second and third toes, which always point forward, are conjoined in some species. Musophagids often have prominent crests and long tails; the turacos are noted for peculiar and quite unique pigments giving them their bright green and red feathers. [more]

Passeriformes

A passerine is a of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: it is roughly twice as diverse as the largest of the mammal orders, the Rodentia. [more]

Piciformes

Six of largely arboreal birds make up the order Piciformes, the best-known of them being the Picidae, which includes the woodpeckers and close relatives. The Piciformes contain about 67 living genera with a little over 400 species, of which the Picidae (woodpeckers and relatives) make up about half. [more]

Psittaciformes

Parrots, also known as psittacines , are of the roughly 372 species in 86 genera that make up the order Psittaciformes, found in most warm and tropical regions. The order is subdivded in three families: the Psittacidae (true parrots), the Cacatuidae (cockatoos) and the Nestoridae. Parrots have a pan-tropical distribution with several species inhabiting the temperate Southern Hemisphere as well. The greatest diversity of parrots is found in South America and Australasia. [more]

Strigiformes

The Strigiformes (Owls) are an of birds of prey, comprising 200 extant species. Most are solitary, and nocturnal, with some exceptions (e.g. the Burrowing Owl). Owls mostly hunt small mammals, insects, and other birds, though a few species specialize in hunting fish. They are found in all regions of the Earth except Antarctica, most of Greenland, and some remote islands. Though owls are typically solitary, the literary collective noun for a group of owls is a parliament. [more]

Trochiliformes

Hummingbirds are in the family Trochilidae, and are native to the Americas. They are among the smallest of birds, and include the smallest extant bird species, the Bee Hummingbirds. They can hover in mid-air by rapidly flapping their wings 12-90 times per second (depending on the species). They can also fly backwards, and are the only group of birds able to do so. Their English name derives from the characteristic hum made by their rapid wing beats. They can fly at speeds exceeding 15 m/s (54 km/h; 34 mph). [more]

Trogoniformes

The trogons and quetzals are in the order Trogoniformes which contains only one family, the Trogonidae. The family contains 39 species in eight genera. The fossil record of the trogons dates back 49 million years to the mid-Eocene. They might constitute a member of the basal radiation of the order Coraciiformes. The word "trogon" is Greek for "nibbling" and refers to the fact that these birds gnaw holes in trees to make their nests. [more]

Turniciformes

The buttonquails or hemipodes are a small family of which resemble, but are unrelated to, the true quails. They inhabit warm grasslands in Asia, Africa, and Australia. [more]

Upupiformes

The Hoopoe , Upupa epops, is a colorful bird that is found across , notable for its distinctive 'crown' of feathers. It is the only extant species in the family Upupidae. One insular species, the Giant Hoopoe is extinct, and the Madgascar subspecies of the Hoopoe is sometimes elevated to a full species. [more]

At least 80 species and subspecies belong to the Order Upupiformes.

More info about the Order Upupiformes may be found here.

References

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Footnotes

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  1. ^ Mindell & Brown (2005)
  2. ^ For a draft phylogeny of Neoaves that is based on a review of massive amounts of published sources and probably rather close to "the real thing", see Mindell et al. (2005)
  3. ^ Mindell et al. (2005)

Sources

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Last Revised: September 22, 2009
2009/09/22 07:05:12