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Bird Families of the World

Birds of the World, Biology 532, revised Jan 2003

Robert B. Payne Recent Families, Birds of the World

This account includes families current or historical, with families and orders adapted from those in Peters and "A Dictionary of Birds," 1985. An alternative arrangement of passerine families by Sibley in DNA chapter in "A Dictionary of Birds", and in Sibley & Ahlquist (1990), can be consulted, a few of these families are included here. In most cases the traditional families (as in Peters, Howard and Moore, and the Dictionary) are used, except where recent publications or the instructor have other views. Grouping of songbird families, and some of suboscines, follows Sibley & Ahlquist (1990) and Barker et al. (2002). The numbers of species and genera are adapted from Sibley & Monroe (1990). Body size: small = warbler or small sparrow, medium = American robin to rock dove, large = crow or larger. Extinct species are from Greenway (1967) and Sibley & Ahlquist (1990); see also Dictionary "extinct birds" and Collar et al. (1994).


ratites. Large, flightless, terrestrial birds with palaeognathous (or dromaeognathous) palate, now restricted to the southern continents and New Zealand (Gondwanaland distribution). Fossils are known in Madagascar and the Palearctic. "Ratite" refers to the large flat sternum which lacks a keel. The number of toes has been reduced to 3 or even 2 (in ostrich) in adaptation to running. Ratites lack morphologically distinct sex chromosomes; they have genetically distinct sex markers on the morphologically indistinct sex chromosomes. The first application of cladistic reasoning in ornithology was Meise (1963), who used behavior characters to estimate relationships among the ratite families, and to determine that ratites and tinamous are sister clades (Pycraft 1900 almost got it right, but no one else did until Meise, who died in 2002 at age 101 years). Meise's scheme has been largely supported in later work in morphology and in molecular genetics of birds.

Struthionidae. Ostrich. Males black and white, females gray. Long legs, two toes. Males build a nest scrape, one female lays most of the eggs, other hens mate with the male and lay in the common nest. The chief hen incubates in the day and pushes out eggs of the others; the male incubates at night. The pair attends the young. 1 species, Africa, formerly southern Asia, feral in Australia, farmed in North America.

Aepyornithodae. Elephant-bird. Extinct. Massive ratites to 3 m tall and 450 kg, stout legs, known from folk tales, fossil bones, and eggshells. 7? species, 2 genera. Madagascar (+? fossil eggshells elsewhere in Old World).

Rheidae. Rhea. Slender ratites with fluffy gray plumage. Tarsus scutellate. The male builds the nest, 1-6 females lay in it, and the male incubates the eggs and cares for the young. 2 species, 2 genera. South America.

Dromaiidae. Emu. Very large, robust, flightless birds with rudimentary wing, no wing quill. Tarsus reticulate. Feathers double-shafted (with aftershaft), plumage dark and drooping. Incubation and parental care is by the male. Island forms were exterminated soon after European settlement. 1 species. Australia.

Casuariidae. Cassowary. Very large birds with coarse, bristle-like, blackish, drooping plumage, aftershaft present, wing with spikey quills, and a casque or helmet on the head. Stout legs. 3 species, 1 genus. New Guinea and Australia (the tropical northeast).

Dinornithidae. Moa. Extinct. Very large (to 3 m high), stout-legged, wingless birds, known from Tertiary to earliest European contact. Herbivorous counterparts of the large mammals of temperate climates. 11 species, 6 genera. New Zealand.

Apterygidae. Kiwi. Large, short-legged, nocturnal birds with shaggy hairlike brown or gray plumage. Young resembles adult in plumage, unlike the other ratites which have a streaked downy plumage. Long slender bill with nostrils near the tip, and a tarsal spur without a skeletal element. 3 species, 1 genus. New Zealand.


Tinamidae. Tinamou. Partridge-size ground birds, chicken-like in shape and in brown, gray, and sandy plumage color, resemble rheas in skeletal anatomy (especially skull) and biology. Sister taxon ot the ratites, the tinamous have a keeled sternum and they can fly. In contrast to phasianids, tinamous have slender, pointed bills, and a depressed rather than arched culmen. Wings short and rounded, the birds can fly short distances but tend to rely on cryptic coloration and stealth to avoid predators. Tail short, soft, often hidden by rump feathers. 3 short front toes, hallux either small and elevated or absent. Palate dromaeognathous. Either sex may have more than one mate. Incubation by male. Eggs are large and brightly colored, gray, green or metallic, with a high gloss. Tinamous lack morphologically distinct sex chromosomes. 47 species, 9 genera. Middle and South America.


Waterfowl. Waterbirds characterized by broad toes, broad bills, often with lamellae that aid in straining food items from water. Palate desmognathous.

Anhimidae. Screamers. Large goose-like birds, heavy body, small head, short arched bill, spurred wing, large thick legs, front toes connected by a slight web, hind toe is long and on the same level as the front three toes. Ribs lack uncinate process, feather tracts are indistinct, pneumatic dermal layer (as in storks with transverse connective tissue). Both parents feed the young. Plumage gray or greenish-black. 3 species, 2 genera. South America.

Anseranatidae. Magpie goose. Large goose-like bird, feet webbed only at the base, long hind toe, wing feathers molt gradually rather than all feathers simultaneously. The social breeding unit is often polygamous and cooperative with both male and females caring for the young. Plumage black and white, face bare. 1 species, 1 genus. New Guinea and Australia.

Anatidae. Ducks, geese, and swans. Medium to large birds, typically water birds with webbed feet, male copulatory organ, hallux absent, or small and elevated. Bill lamellate in many species. Magpie goose (Australia) may be more closely related to screamers than to ducks and geese. Subfamilies and tribes (after Livezey): Dendrogcygninae, whistling ducks, long legs, tarsus reticulate; Anserinae, geese and swans, large waterfowl with biparental care; tarsus reticulate: tribes Cereopsini, Cape Barren goose (gray plumage, short bill); Anserini, geese and swans, short deep bill; Stictonettinae, freckled duck (looks like a dabbling duck but with reticulate tarsus and a smile); Tadorninae shelducks and allies, including tribes Merganettini torrent ducks Merganetta (small, long stiff tail), blue duck Hymenolaimus and steamer ducks Tachyeres (plumage gray, wings short, heavy bill); Plectropterini spur-winged goose Plectropterus, comb ducks Sarkidiornis; and Tadornini shelducks Tadorna (plumage in green, rufous, white or black or combination, bill often brightly colored, shield at base) and South American sheldgeese Chloephaga; Anatinae "true ducks", including tribes Malacorhynchini pink-eared duck Malacorhynchus and Salvadorina Salvadori's duck; Anatini perching ducks Aix and Cairina, with long legs for a duck, long hallux, some are cavity nesters; pygmy goose Nettapus, maned duck Chenonetta, and dabbling ducks Anas, often with metallic speculum in wing, foot well webbed with hallux unlobed; Aythyini pochards, diving ducks, lack metallic speculum, foot well webbed with hallux lobed; Mergini sea ducks and mergansers, diving ducks that take fish and have serrated bills, or thick-billed ducks such as eiders and scoters that take bottom-living invertebrates as mollusks; and Oxyurini stifftails Oxyura and musk duck Biziura, hallux small, plumage rufous and black, includes the obligate brood-parasitic black-headed duck Heteronetta.

Recent molecular genetic studies (in progress) indicate changes from the above, including: (1) freckled duck Stictonetta is a stifftail not a tribe, (2) pygmy geese Nettapus are related to stifftails Oxyurini, (3) musk duck Biziura and pink-eared duck Malacorhynchus are basal to all other ducks Anatinae and are not each other's closest relatives, (4) fossil "geese" moa-nalos of Hawaii are dabbling ducks not geese, (5) Tachyeres steamer ducks are dabbling ducks Anatini, (6) Merganetta torrent ducks are perching ducks, (7) Chenonetta maned duck and Salvadorina are dabbling ducks, and (8) the perching ducks are paraphyletic.

Mating systems and parental care vary among groups: musk duck breed in leks, geese and swans are biparental (male and female both look after the young), many ducks are female-care only (migratory species) and others are biparental (resident species especially in South America), many ducks are sometimes (facultative) brood-parasites (e.g. redhead, on other redheads and on canvasbacks), and black-headed duck is the only precocial obligate brood-parasitic bird. 157 species (3 extinct), 45 genera. Cosmopolitan.


Chicken-like birds. Vegetarian ground birds with short, stout beaks; most have short rounded wings and fly only short distances. The megapodes or mound-builders are exceptional among birds in using heat from the ground to incubate their eggs. Palate schizognathous, and a "secondary" basipterygoid process is present.

Megapodiidae. Mound-builders. Large brownish to black chicken-like birds with very large feet and claws. Eggs are buried, not incubated by the heat of the bird, and develop by environmental heat-- in mound-builders by decaying vegetation, with temperature regulated by the male, and in burrow nesters by geothermal volcanic heat or by solar heat on sand. A species may use more than one kind of incubation site depending on local habitat, and individual malleefowl change their behavior with the season. A mound-building species in New Guinea may be a brood parasite on other species. Mating behavior and social organization are variable, monogamous in malleefowl where male guards a mound, and in many Megapodius where male guards a female and remains in a pair; or promiscuous &endash; polygynous in brush turkeys where male guards a mound and allows females that copulate with him to lay there. Some species are highly colonial (> 50,000 birds nest in a common area in one species). Young are the most precocial of birds, have contour feathers when they hatch (feet first), leave the natal mound (scratch their way out while lying on their back), and feed on their own with no social behavior with other young and no other parental care. 19 species, 6 genera. Australia, New Guinea, and eastern Indonesia to Philippines, Polynesia, and Melanesia in Western Pacific (all east of Wallace's line), also Andaman and Nicobar Islands (Bay of Bengal) = Indo-Australian.

Cracidae. Curassows, guans, and chachalaca. Large birds, mainly arboreal and forest living, with long legs, large incumbent hallux, and long tail, short wings, base of bill often enlarged, and bird often ornamented on bill or head. 69 species, 17 genera. Neotropical.

Phasianidae. Pheasants, partridges and francolins, Old World quail, New World quail, turkey, grouse, and guinea fowl. Ground birds, short-winged, short-billed, typically with an arched culmen. Groups included are (1) New World quail, small and compact, short stout bill with short, very curved culmen and serrated or toothed mandibular tomium, nostrils bare, hallux elevated, no tarsal spur, tarsal scutellation: single row of broad transverse scutes on front, on the back 2 or more row of long scutes and also small scales. 31 species, 9 genera. Nearctic and Neotropical. Sometimes recognized as a distinct family, Odontophoridae. (2) guinea fowl, upper part of head bare, often with a bony crest, helmet or feather crest, or a feathered patch, the tail small and drooping. 6 species, 4 genera. Africa. (3) pheasants, hallux elevated, tomia not serrated, tail molt centripetal, often with metallic male plumage. Includes tragopans, argus, monal and peacocks. 50 species, 16 genera. Old World. (4) partridge, turkey (large with colored, erectile wattles, and tarsal spurs), francolin and Old World quail, a variable group, small to large, a few with tarsal spurs, usually monogamous, tail molt centrifugal. 108 species, 22 genera. Old World, except turkeys (Nearctic and Neotropical). note - (3) and (4) may not be monotypic groups. (5) grouse, nostrils covered by feathers, tarsus and toe often feathers, or toes laterally pectinate, long aftershaft, 17 species, 6 genera. Holarctic. Phasianidae includes 214 species (1 extinct), 58 genera. Cosmopolitan.


Mostly tropical birds with plumed crests, pointed bills, round wings and small feet with some fusing of the three forward toes. Rollers and allies, typically with a syndactyl foot, toes 2-3-4 united at base, 3-4 united through much of the length. Number and arrangement of toes varies within the order. Palate desmognathous, except in trogons.

Coraciidae. Rollers. Medium-sized syndactyl birds with bill crow-like or broad and short, hooked; legs stout, toes syndactyl, plumage often with blues and purples. 12 species, 2 genera. Old World.

Brachypteracidae. Ground-rollers. Medium sized, terrestrial, syndactyl, long-legged birds, large stout bill, long tail, male plumage with blues and rufous. 5 species, 3 genera. Madagascar.

Leptosomatidae. Cuckoo-roller. Medium-large pigeon-sized, plumage gray, with metallic green and copper tones above in male, females brown and black, powderdown well developed on flanks, bill stout and slightly decurved, legs short, toes zygodactyl in life. 1 species. Madagascar and Comoro Islands.

Trogonidae. Trogons. Medium-sized, brightly colored (green, red, or blue and yellow), soft-plumaged birds with long tail, often patterned. Bill short, broad at base, curved culmen, tarsus short, heterodactyl, toes 1-2 directed back, 3-4 directed forward (live bird has all toes forward). Palate schizognathous. 39 species, 6 genera. Tropical (Neotropical, Africa, Asia).

Momotidae. Motmots. Medium-sized birds with long tail, long, broad, slightly decurved bill, usually serrate. Plumage soft-textured, colors noniridescent greens, blues, and browns. 9 species, 6 genera. Neotropical.

Todidae. Todies. Tiny syndactyl birds with long, flat, pointed bill, short rounded tail, plumage green above, pink and white below. 5 species, 1 genus. Greater Antilles.

Meropidae. Bee-eaters. Small to medium-sized syndactyl birds with bill long, slender, laterally compressed, pointed, and slightly decurved, feet small. Plumage colorful, often with greens, blues, and yellows. 24 species, 3 genera. Temperate and tropical areas, Old World.

Alcedinidae. Kingfishers. Small to medium-sized birds with long, sometimes laterally compressed beaks, maxilla straight and pointed, mandible wide and gonys angled. Head large, neck short, tarsus short, toes typically syndactyl, including 3-toed species with toe 2 vestigial or absent. 84 species, 16 genera. Cosmopolitan.

Phoeniculidae. Wood-hoopoes. Medium-sized birds, weakly syndactyl foot, short tarsus, plumage partly or entirely uniform (usually glossy) black, tail long, bill long and slender, decurved in most species. 8 species, 2 genera. Africa.

Upupidae. Hoopoe. Medium-sized, weakly syndactyl birds with long, slender bill. Plumage buff, white, and black, and a long crest. 1 species. Palearctic, Indomalayan, and African regions.

Bucerotidae. Hornbills. Large birds, long and massive bills, often with a casque. Plumage black and white in most species. Bare skin around eye, sometimes on throat; prominent eyelashes. Fused axis and atlas vertebrae. Feet short, stout, broad-soled, syndactyl toes. 56 species, 9 genera. Old World Tropics, except Madagascar and Australia, mainly in forests.


Woodpeckers and allies. Tree-dwelling, cavity-nesting birds with brightly colored plumage, specialized bills, and zygodactyl feet (two toes point forward and two point backward. Nestlings have a heel-pad, smooth in jacamars and puffbirds, papillate in the other groups. Skeleton with trochlea IV enlarged (and rotated with a sehnenhalter in suborder Picae).

Galbulidae. Jacamars. Small- or middle-sized birds with long, pointed, slender bills, and plumage soft texture with metallic green, gold or bronze reflections, and aftershaft; tarsus smooth behind; no vomer. Zygodactyl, one species lacks a hallux. 18 species, 5 genera. Neotropical.

Bucconidae. Puffbirds. Small to medium-sized, lax-plumaged birds, dull-colored in black, gray, brown, and white, and aftershaft, bill often decurved or hooked at tip, feet zygodactyl, tarsus scutellate behind. 33 species, 10 genera. Neotropical.

Indicatoridae. Honeyguides. Small, brown, zygodactyl birds typically with 9 primaries, 12 rectrices (10 in Prodotiscus), the outer tail feathers white. Brood parasites. Skin thick; nostrils dorsal in a large nasal fossa. 17 species, 4 genera. Africa, India to the Malaysian archipelago.

Capitonidae. Barbets. Small to middle-sized zygodactyl birds with conspicuous bristles at base of bill (less conspicuous in ground barbets), 10 rectrices. Bill stout in typical fruit-eating barbets, slender in the insectivorous ground barbets (Africa). Clavicles separate in most forms, furculum present in Asian barbets. Plumage colors often bright with red, yellow and (Asia and some South American) nonmetallic green. 82 species, 13 genera, not including the toucans. Neotropical, African, and Indomalayan.

Ramphastinae. Toucans. Middle-sized or large birds with enormous, brightly colored and marked bill, no casque, interior of bone is a network of bony fibers, clavicles separate. Toucans are a subset of barbets. 41 species, 6 genera. Neotropical.

Picidae. Woodpeckers. Small to medium-large arboreal birds with a stout, chisel-like bill and stiff rectrices in typical woodpeckers, tail soft in piculets, tail soft and bill slender in wrynecks. Toes zygodactyl 2-2, a few species lack a hallux. The tarsometatarsus has a well-developed sehnenhalter behind trochlea #4. Toes #4 is used in lateral or forward position when climbing a vertical treetrunk, toe #1 is small or functionless in climbing. 215 species, 28 genera. Cosmopolitan, except Australian region and Madagascar.


Cuculidae. Cuckoos. Zygodactyl birds with a long tail, short legs in arboreal cuckoos and long legs in ground cuckoos. Nearly half the species are brood parasites (54 in the Old World, 3 in the New World), and brood parasitism evolved twice in the Old World Cuculinae and once in the New World Neomorphinae cuckoos. Other cuckoos rear their own young, and the anis and guira cuckoo (four species, Crotophaginae) are group-living cooperative breeders. Cuculinae include nesting arboreal cuckoos of Old World (the malkohas) and the New World (coccyzine cuckoos) as well as the Old World brood parasites. Other groups are the Old World ground cuckoos Carpococcyx and couas Coua (ground and arboreal cuckoos of Madagascar) Couinae, coucals Centropodinae, anis Crotophaginae, and New World ground cuckoos Neomorphinae with roadrunners Geococcyx and the brood parasites Tapera and Dromococcyx. Plumage with eye-lashes, wing eutaxic, 10 primaries, 9-13 secondaries (10 in Clamator; 11 in Clamator glandarius), tail with 10 rectrices (8 in anis). Wing molt is transilient, a wave of molt jumps over the neighboring old feathers. In the simple form of transilient molt, the odd-numbered feathers are replaced first, then the even-numbered feathers, with primary sequence 9-7-5-3-10-8-6-4, variations occur on this theme with outer P in transilient ascending molt (9-7-5-10-8-6) and inner P in stepwise descending molt (1-2-3-4). Tail feathers are replaced with one of the three long feathers T1-2-3 retained until another long T feather on each side is completely replaced, so the bird always has a long tail. Skeleton: palate desmognathous, vomer small, tarsometatarsus has an accessory trochlea IV (sehnenhalter) small compared with other zygodactyl birds, tarsometatarsus has a hypotarsus with two canals side by side; and humerus has a characteristic shape of the shaft and deltoid crest. 139 species (1 recently extinct species c. 1835, and -- not included in the 139 species -- 3 subfossil species c. 1000 y.a., two couas in Madagascar and one cuculine on St Helena Island), 32 genera. Cosmopolitan, mainly Old World and tropical.


Musophagidae. Turacos or "plantain eaters". Short-billed, long-tailed birds, semi-zygodactyl foot (outer toe can go forward, usually is directed outward, and can rotate backward within 70o of the hallux) with short toes and claws. Plumage of most species includes greens and reds due to porphyrin (pigments unique to turacos), plumage gray in other species. Wing eutaxic, molt is descending (sometimes with a second late center for the outer primaries), aftershaft present (vs cuckoos), oil gland tufted (nude in cuckoos), eye-lashes absent (present in cuckoos). Young covered with blackish down, a few have a short wing claw (Moreau 1938). Palate desmognathous. Skeletal traits, where different from cuckoos: basipterygoid present, vomer absent, an uncinate bone in skull (present in a few cuckoos, as koels), 15 cervical vertebrae (14 in cuckoos), clavicles unfused (no furcula), coracoids overlap (separate in cuckoos), distinct configuration of lacrimal bone, coracoid with bony canal formed by dorsal processes of coracoid, atlas notched (not perforated), 19 presacral vertebrae + 5 dorsal vertebrae (17-18 + 4 in cuckoos), hypotarsus with 1 bony canal (2 in cuckoos), foot semi-zygodactyl; leg muscles also differ from cuckoos'. Turacos eat fruit, mainly figs; bananas (= Musa) are not native to Africa. 23 species, 5 genera. Africa.


Coliidae. Mousebirds. Medium-sized drab gray birds, feathers with hair-like form and long aftershafts, poorly waterproofed. Head with a crest, wings short and round, tail long and graduated, crest, 4 toes directed forward in pamprodactyl arrangement (inner toe and outer toe each are reversible). Palate indirectly desmognathous, vomer is minute. Cranium with tight fit of mandible, quadrate, and lateral occipital process of basicranium with unique horizontal orientation of articular surface. Pygostyle unique, elongate, has two sets of lateral processes. Mousebirds often hang upside down. Torpid when food is in short supply. Mid-Eocene fossils in Europe. 6 species, 2 genera. Africa.


Psittacidae. Parrots. Medium to large birds with colorful plumage, a strongly curved upper mandible overlapping a short lower mandible, usually an unfeathered cere at base of bill, tarsometatarsus short, foot zygodactyl and covered with granular scales. Three pairs of syringeal muscles. Skeleton: palate desmognathous, palatines enlarged and rotated ventrad, adapted for forceful movement of upper mandible on nasofrontal hinge; dorsal vertebrae somewhat opisthocoelous. Wing molt begins with P6 and progresses inward and outward. Flightless parrots occur in Australia and New Zealand, others in Mascarene islands are now extinct. Cockatoos (crested, lack greens and blues in plumage), lories (brush tongues), and certain other groups are sometimes given family status. Conures are small and short-tailed, New World; "parakeets" are usually small in body and long in tail. Arinae (New World) parrotlets, conures, parakeets, Amazons, macaws and others, defecate in the roosting cavity and copulate side-by-side; Psittacinae, Africa, African grey parrot Psittacus, Cape and Senegal parrots Poicephalus, Madagascar black parrots Coracopsis; Cacatuinae (Wallacea, New Guinea and Australia), crested, lack greens and blues in plumage, have powderdown; Platycercinae, Australia and New Zealand (Platycercus rosellas, grass parrots and Bourke's parrot Neophema, budgerigar "Australian parakeet Melopsittacus, Pezoporus ground parrots, also Strigops and Nestor) typically with broad tail feathers (compared with Asian parakeets); Psittaculinae (Asia and Africa to Fiji, including Asian parakeets, perhaps African lovebirds, perhaps eclectus parrots Eclectus) (all these most closely related to lories); and Lorinae (lories with a tongue with brush-tip for feeding on nectar, fig-parrots with deep bill and a notch on upper mandible, fungus-eating pygmy-parrots Micropsitta with deep lower mandible, and vulturine parrot Psittrichas of New Guinea), a laterally compressed bill which typically lacks honing serrations (the latter three groups are not typical), from New Guinea and Philippines to islands of South Pacific. 358 species (14 extinct, 90 endangered or threatened), 80 genera. Cosmopolitan, mainly Neotropical and Australasia.


Raptoral bill and feet, feet zygodactyl, plumage soft. Nocturnal or crepuscular predators. As in Falconiformes, reverse size-dimorphism in which females are larger than males.

Tytonidae. Barn owls, bay owl. Medium to large owls with soft plumage, heart-shaped facial disc and long slender legs, middle toenail indistinctly pectinate, zygodactyl raptorial feet. Skeleton with nut-shaped disk on columnar stapes. 17 species, 2 genera (Tyto, Pholidornis). Cosmopolitan.

Strigidae. Owls. Medium to large, soft-plumaged, short-tailed, big-headed birds with a rounded facial disc, sharply curved bill and zygodactyl raptorial feet. Eyes directed forward. Bony ring in tarsometatarsus, bony arch on inner surface of radius (also in Tyto). 178 species (one "extinct" in India was rediscovered and photographed in the field in 1997, more than 120 years since it had last been seen), 25 genera. Cosmopolitan.


Nightbirds. Crepuscular and nocturnal birds with long wings, cryptically brown plumage and short legs. Small bills with large heads and unusually wide mouths, many catch insects in flight or small prey on the ground.

Steatornithidae. Oilbird. Large fruit-eating bird with powerful hooked bill and spotted plumage. Nocturnal, nests in caves. 1 species. Neotropical.

Podargidae. Frogmouths. Medium to large, soft-plumaged, thick-billed nocturnal birds that capture prey by flying to the ground from an arboreal or ground perch. 14 species, 2 genera. Tropical and subtropical Indomalayan and Australasian.

Caprimulgidae. Nightjars, including nighthawks and goatsuckers. Medium-sized nocturnal insect eaters with soft plumage, weak bill, extremely wide gape, usually with bristles, large eyes. Genus Eurostopodus may be a distinct family. Toes small, middle toe with pectinate claw. 77 species (1 extinct), 15 genera. Temperate and tropical continents.

Nyctibiidae. Potoos. Medium-sized nocturnal birds with soft, cryptically marked plumage, a small bill, terminally decurved with a projecting "tooth" on edge of upper mandible, and a huge gape, feed by capturing insects in flight. 7 species, 1 genus. Neotropical.

Aegothelidae. Owlet-frogmouths. Small to medium soft-plumaged, cryptic bird with tiny bill, wide gape, filoplumes, and barbed rictal bristles, tarsus longer than in other caprimulgiforms. 8 species, 1 genus. Australasia.


Swifts and hummingbirds. Small, fast, acrobatic birds that feed in flight, on the wing, taking insects (swifts) or nectar (hummingbirds). Small feet, powerful flight muscles, a short humerus and long manus, furcula U-shaped, left carotid (except Cypseloides which has two), simple pelvic muscle formula ("A"), 10 primaries, the outer the longest.

Apodidae. Swifts. Small to medium birds with long pointed stiff wings, short humerus with a proximal ectepicotylar process, short ulna, long carpus, small bill with wide gape. Tarsus short, toe arrangement variable: Cypselurini toes 1-3 (anisodactyl), weak, palatines elongate (more broad in other swifts), 2 carotid arteries (others have 1), do not use saliva in nest (others do); Apodini, e.g. Apus, toes 1-2 oppose 3-4 (heterodactyl) in life, all pointing forward to grasp either side of a narrow perch, like a chameleon (often pamprodactyl with all 4 forward together in museum specimens) (Schoutedenapus is anisodactyl, otherwise looks like Apus); and Chaeturini, e.g. Chaetura, 1-3, strong (no hallux in Collocalia papuensis), stiff tail (spinetails) (except Collocalia, which are sometimes recognized as a distinct tribe). 99 species, 18 genera. Cosmopolitan.

Hemiprocnidae. Crested swifts. Swifts with crest and metallic colors in the plumage. Toes long, slender, anisodactyl, hallux not reversible, humerus short with an ectepicotylar process at mid-length. 4 species, 1 genus. India and southern Asia to northern Australasia (Solomon Islands).

Trochilidae. Hummingbirds. Tiny to small birds with usually elongated, slender, straight bills, feed on nectar; wings short, pointed, stiff, short humerus; very small legs and feet. In nearly all species, only the female cares for the young. Plumage has brilliances or iridescences in most species, either the male or both sexes. The young are fed insects as well as nectar. Nest in open cups, the young beg in response to the breeze of female's wings on their natal down, and do not give begging calls. High metabolic rates for their size, with high concentrations of muscle mitochondria allow rapid energy output for hovering flight; metabolic rate higher than other birds when perched. Torpid (low body temperature, behaviorally inactive) at night under a wide range of environmental temperatures. Relationships within the family are not well known. The basal group are the hermits Phaethorninithinae (Ramphodon, Eutoxeres, Glaucis, Threnetes, Anopetia, Phaethornis), others in Trochilinae (from basal to derived) are the mangoes, the brilliants, the coquettes, the emeralds, and the Mountain gems and bees. 319 species, 109 genera. New World, mainly South America.


Opisthocomidae. Hoatzin. Large arboreal bird of river thickets, with bare face and scraggy crest, long tail, a sternal callosity, tarsus with large hexagonal scales aft and small reticulate scales post, large feet. Relationships uncertain -- a gruiform (Seebohm 1888, 1895, Livezey & Zusi 2001), a galliform, a cuckoo, a tauraco, a pigeon, or an order of its own. Hoatzin is not zygodactyl, its foot has a large incumbent hallux; nevertheless trochlea IV has a small accessory process as in zygodactyl birds. Young precocial, covered with down, down on both pterylae and apteria (as in gruiforms), two sets of down (as in gruiforms), and hooks on wings (digits 1 and 2) used (with hooked bill and claws, as in parrot) in climbing when leave the nest (nidifugous). Young has 7 or 8 primaries (the outer ones retarded in development, leaving space for the claw), older young and adult have 10. Adult has a large crop, ferments green leaves with microbes in proventricular foregut using a unique lysozyme, and the large crop displaces the keel of sternum, keel prominent at posterior (not anterior) end of sternum, underlying the sternal callosity; coracoids long, extend to the displaced sternum. Plumage with eye-lashes, neck lacks lateral apteryae (as also in Heliornis and seriemas), wing eutaxic, 10 primaries, 11 secondaries, tail with 10 rectrices, wing molt regular stepwise descending, postjuvenal tail molt from outer and inner towards T3, adult tail molt irregular (the molt features unlike cuckoos). Leg muscles are like some cuckoos and differ from other cuckoos. Eggs are spotted. Skeleton: palate schizognathous, thoracic vertebrae fused (as in galliforms, doves, and some gruiforms), hypotarsus with 1 bony canal. Skeleton: skull lacks basipterygoid process, coracoid has large subclavicular process, sternum lacks deep notches, thoracic vertebrae have few ventral processes, angle of mandible is simple (not prolonged and recurved), episternum is not pierced to allow coracoids to meet at their bases (in these features, hoatzin differs from galliforms and resembles some gruiforms such as trumpeter). Hoatzin is a cooperative breeder. 1 species, 1 genus. South America.


Cranes, rails, and allies. A mixed group of mostly wetland birds with diverse morphology and lifestyles. Palate schizognathous (indirectly desmognathous in seriemas and kagu), skull schizorhinal (sunbittern, cranes, limpkin) or holorhinal (most rails, finfoot, trumpeters, seriemas, bustard), nostrils pervious (most) or not (kagu), lacrymals distinct from ectethmoid, ramphotheca simple, basipterygoid process absent (except in crowned cranes and a bustard) (vs present in Charadriiformes), quadrate with a double head (as in Galliformes and Charadriiformes), cervical vertebrae 14-20, dorsal vertebrae heterocoelous (vs opisthocoelous in Charadriiformes), sternum 2-notched (1 on each side) (rails, seriemas, finfoot, sungrebe), 4-notched (bustards) or entire (cranes, limpkin, trumpeters, kagu), hallux present, elevated (incumbent in sunbitterns, limpkin) or absent (bustards), sternum with spina interna absent, distal ends of ilium and ischium united (as in Charadriiformes and Galliformes), hypotarsus with high ridges (kagu, rails), complex (cranes, bustards) or simple (sunbittern), wing with 10 or 11 primaries (rarely 8 or 9 in some rails), wing diastataxic in most (eutaxic in some rails and in trumpeters, seriemas, and kagu), rectrices 12 (larger number in bustards), toes not webbed or (finfoot) with a basal web. Fossil gruiforms include Ý Phorusrhacidae (large flightless predators of South America, also Florida) and Ý Aptornithidae (New Zealand).

Rallidae. Rails. Small to medium-large birds with the body laterally compressed, moderate to long legs and toes, short wings, short and soft tail, sexes alike (except Sarothrura). Plumage black to browns, often streaked. Toes unwebbed; lobed in coots. Bill shape variable, skull holorhinal (except Nesolimnas), nostrils perforate (impervious in some, e.g. Rallicula). Small species are nocturnal. Includes cooperative breeders (Tasmanian native hen is best known), moorhen is sometimes polyandrous. Nostrils holorhinal. Mainly aquatic or marshy habitats, some are grassland or forest birds. Wing with 10-11 primaries (8-9 in some), secondaries diastataxic in most, eutaxic in Himantornis and Amaurolimnas. Several island species are flightless; flightlessness has evolved many times in this family, perhaps by simple change in the timing of development that maintains the avian embryonic traits of a disproportionately large pelvis and hind legs, greatly reduced wings and a sternum with little or no keel. One estimate is of 1,700 island rail species having gone extinct in the posthuman occupation period, from recent palaeoarchaeological surveys especially in the Pacific. One flightless rail, Notornis, was first discovered as a fossil, then later was found alive on New Zealand. 142 species (9 extinct, island forms known from skins), 34 genera. Cosmopolitan, including many oceanic islands.

Aramidae. Limpkin. Large rail-like bird, bill long, decurved and laterally compressed; streaked brown plumage, with skeletal and plumage characters that are like cranes. 1 species. Neotropical.

Psophiidae. Trumpeters. Large terrestrial vegetarian birds of tropical rain-forest, short chicken-like bill, long legs, short tail, plumage mainly velvety black, tarsus scutellate. Vertebrae with hypapophyses on 3 dorsals. Behavior noisy, gregarious, social, group-living, pets of Amazon people. 3 species, 1 genus. Neotropical.

Gruidae. Cranes. Large, long-legged, long-necked wading or ground birds with slender bills (shorter than tarsus), short toes. Ornamental secondaries hang over the tail in all but one species, also ornaments of crests, hackles, and lappets. Sarus crane Grus antigone is the tallest flying bird. Trachea large, coiled into the sternum in Grus, not large or coiled in crowned cranes Balearica or Siberian crane Grus leucogeranus; the sternum unnotched, paired supraoccipital foramina, basipterygoid present (small) in crowned cranes. Some cranes are long-distance migrants, others live in tropical wetlands all year. 15 species, 2 genera. Cosmopolitan except South America.

Heliornithidae. Finfoot. Aquatic birds with toes lobed (banded black and yellow in New World species), web at base, hallux incumbent, a pectinate middle toenail (African finfoot); head small, bill slender straight rail-like, tail long stiff 18 or more feathers. New World finfoot ("sungrebe") male has pockets of skin on flanks under his wing, carries an altricial hatchling (naked, blind) in each pocket. African and Asian finfoot chick is downy, brooded by female (African, ?Asian), precocial, can swim at 2 days. Plumage close-set, neck completely feathered, aftershaft absent. 3 species, 3 genera. Neotropical, Africa, and India to Malaysia.

Eurypygidae. Sunbittern. Graceful, long-legged, long- and slender-necked bird with long, slender bill, slender unlobed toes, and a distinctive banded and variegated plumage of orange-chestnut and buff. Tail round, feathers not stiff, aftershaft present but small. Semi-arboreal, live along watercourses in lowland forests. Young downy, stay in nest for 3-4 weeks, tended by both parents. 1 species. Neotropical.

Rhynochetidae. Kagu. Medium-large flightless ground bird with light gray plumage, short tail, and long loose crest. Bill slender, slightly decurved, not perforate, with nasal operculum, plumage shaggy with large aftershafts, bill and feet reddish-orange. Skull lacks occipital foramina above the foramen magnum (vs cranes), powderdown occurs in scattered patches. 1 species. New Caledonia.

Cariamidae. Seriema. Medium-large cursorial birds of drier areas. Long neck and legs, long tail, loosely-webbed plumage. Omnivorous and predatory. Aftershaft present, nail of second toe talon-like. Skull lacks occipital foramina. Numerous fossils are known in North and South America. 2 species, 2 genera. South America.

Otididae. Bustards. Medium to large terrestrial birds of dry open country, with a cautious, attentive walk. Stout body, flat head, and short, straight bill. Tarsus with hexagonal scales, no hallux, feet with 3 short, broad toes with flattened nails. Ornamental plumage in some species. Penis present in males. Large aftershaft. 16-20 tail feathers. No oil gland, pink powderdown or underdown present in apteria. Sternum 4-notched. Basipterygoid absent (present in houbara Chlamydotis undulata). Several species lek in display. 25 species, 6 genera. Old World.


Turnicidae. Buttonquail. Small, quail-like ground birds with small slender bill, short, rounded wings, short tails, plumage streaked above, feathers with aftershaft, and only 3 toes. Palate aegithognathous or nearly so, vomer short, broad, truncated anteriorly and paired posteriorly. Basipterygoid process large, originates from basisphenoid rostrum. Skeleton differs from quails: skull schizorhinal, thoracic vertebrae in front of sacral vertebrae are not fused, coracoids have subclavicular processes, humerus not pneumatic, sternum has only one lateral xiphoid process; skeleton more like gruiformes (vomer unlike gruiformes). Wing eutaxic. Mating often polyandrous, female larger than male and more brightly colored, female with large trachea and esophageal bulb, loud and low hooting calls in courtship behavior, incubation period 12-13 days, precocial, young fly in a week, continue to grow, breed a few weeks later when conditions permit. 17 species, 2 genera. Old World.


Mesitornithidae. Mesites. Pigeon-size birds of Madagascar, of uncertain relationships, many skeletal characters like gruiformes. Soft brown plumage, 5 pairs of powderdown patches, full tails, short wings, sternum with 1 pair of notches, spina interna present (unlike gruiformes), nostrils perforate, reduced flight but able to fly, long incumbent to elevated hallux, schizorhinal palate, eutaxic, 16 rectrices. Nest in trees, downy precocial young, both sexes incubate and feed the young. Walk around woodland on the ground, forage in and under dead leaves, live in groups, cooperative breeders. 3 species, 2 genera. Madagascar.


Columbidae. Pigeons. Fast-flying, seed and fruit eating birds with long pointed wings. Small to large birds with plumage dense and soft, small heads, bill small, hard and slightly swollen at tip, soft at base and with a naked cere, operculum over the nostril, plumage colors usually soft shades of brown, gray, or vinaceous; bright yellows and greens in many fruit doves, size large in New Guinea crested Goura. Palate schizognathous, basipterygoid present; wing diastataxic, molt descending. Young have sparse down, remain in the nest and are fed regurgitated crop "milk". 312 species (6 extinct), 42 genera. Cosmopolitan, including oceanic islands. Family includes the extinct "Raphidae" Ý dodo from Mauritius and Ý solitaire from Rodriguez, large flightless birds of the Mascarene islands in the western Indian Ocean, 3 species, 2 genera (included in numbers for Columbidae), dodo and solitaire are each others' closest relatives in a clade with Caloenas (Nicobar pigeon), Goura (crowned pigeon) and Didunculus (tooth-billed pigeon).


Shorebirds and allies. Typical waders are small, fast flyers with long legs and brown plumage, gulls are stout scavenging or fish-eating birds of marine and freshwater habitats, and auks are compact surface-diving seabirds. Birds vary in morphology and ecology, birds of dry country, shorebirds, aerial birds like swallows that feed on the wing, birds that dive like penguins. Wing diastataxic, aftershaft present, number of rectrices varies (10 in jacana, 14 in painted snipe, 14-18 in sandgrouse). Downy young, nidifugous (chicks quick to leave the nest, less quick in some alcids). Skeleton: palate schizognathous (seedsnipe aegithognathous), basipterygoid present (except seedsnipe, sheathbill, crab-plover, alcids), supraorbital groove present in marine groups, vertebrae somewhat opisthocoelous (concave behind) though in much less degree than in penguins (vertebrae also somewhat opisthocoelous in Pelecaniformes, parrots, and oilbird), the number of cervical vertebrae varies.

Pedionomidae. Plains-wanderer. Small terrestrial buttonquail-like bird with slender bill, short tail, long neck, long legs, wing diastataxic, palate schizognathous, scutellate tarsus, and a hallux (vs buttonquail). Nocturnal in behavior, solitary. Downy young with blackish spots above. Polyandrous, male parental care in captivity. 1 species, Australia.

Jacanidae. Jacanas. Aquatic birds with long legs and extremely long toes and long straight claws, walk on floating aquatic vegetation. Sexes alike in plumage, females larger than males in the larger species, in which males incubate and care for the young and females are polygamous. Some with carpal spur. In some jacanas, radius is flat and curved, knobbed or thickened, used to carry the young under the wing. 8 species, 6 genera. Cosmopolitan, tropical.

Rostratulidae. Painted snipe. Snipe-like birds with long, slightly decurved bills, swollen at tip, bold color patterns, females more colorful and larger than males and with enlarged trachea. Males incubate and care for the young. 2 species, 1 genus. South America, Africa, southern Asia, Australia.

Scolopacidae. Sandpipers and phalaropes. Small to medium-large "waders" of tundra, marshlands, grasslands, and forests. Plumage typically streaked above, bill slender and straight in snipe Gallinago and woodcock (Scolopax), in dowitchers (Limnodromas), in calidrine sandpipers (Calidris and others), and the more slender-billed tringine sandpipers (Tringa and others), bill decurved in Numenius and other curlews (including upland sandpiper), recurved in godwits (Limosa), spatulate in spoonbill sandpiper, short in surfbird (Aphriza); bill with sensory pits near the tip, not swollen distally (vs plovers). Tarsus usually transversely scutellate front and back (except in curlews), 4 toes (3 in sanderling), toes lobed in phalaropes (Phalaropus, Steganopus). Wing is eutaxic in some species and diastataxic in others. Mating system and parental care vary among species (monogamous, polygynous, polyandrous). 88 species (1 extinct), 21 genera. Cosmopolitan, many breed at high latitudes in Holarctic.

Thinocoridae. Seedsnipe. Short-billed, cryptically-plumaged above, with small heads, shield-like covering (operculum) of the long slit nostril, bill short, pointed, sparrow-to partridge-like, wings long and pointed, short legs, long middle toe, vestigial hallux. Skeleton: palate aegithognathous, no basipterygoid process or occipital fontanelles, the basisphenoid rostrum thick and long, the vomer broad and forked posteriorly, the hallux present. Apteria with thick black down. 4 species, 2 genera. South America.

Charadriidae. Plovers and lapwings. Small- to medium-sized ground birds, often along shores in migration (shorebirds or waders). Most species have unstreaked plumage (spangled in Pluvialis golden plovers), gray or brown above, white below, often with bold bar(s) on breast. Bill slender, straight, shorter than tarsus and shorter than head, swollen at tip in plovers, turned to right in Anarhynchus wrybill. Wings spurred or knobbed in many lapwings Vanellus, which have pied plumage and may have long crest or wattles. 3 toes (vestigial hallux in black-bellied plover). Includes the beach scavenger Magellanic plover Pluvianellus ("Pluvianellidae" of Dictionary of Birds). Head large, eye large. Toes moderately long, hallux vestigial or (most species) lacking. 67 species, 11 genera. Cosmopolitan.

Haematopodidae. Oystercatchers. Large waders with bill long, chisel-like, laterally compressed. Legs orange, feet with 3 short toes, no hallux, toe webs reduced, tarsus covered with small hexagonal scales Plumage black or pied black and white. 11 species (1 extinct), 1 genus. Worldwide coastal distribution at temperate latitudes.

Recurvirostridae. Avocets and stilts. Medium to large long-legged waders, plumage unstreaked, pied black and white (brown, gray, black and white in ibisbill). Bill slender, recurved in avocets, straight in stilts, decurved in ibisbill. Tarsus reticulate, hallux small or absent. 11 species, 4 genera, including Australian banded stilt Cladorhynchus and montane central Asian ibisbill Ibidorhyncha ("Ibidorhynchidae" of Dictionary). Cosmopolitan.

Dromadidae. Crab-plover. Large shorebird, adult plumage white with black mantle and primaries, bill large and laterally compressed, no groove, longer than head, nostrils perforate, legs long, 4 toes, middle toenail dilated, notched or pectinate. Skeleton: schizorhinal, no basipterygoid processes or occipital fontanelles. 1 species. Indian Ocean islands and continental coasts from Africa and Arabia to Bay of Bengal.

Burhinidae. Thickknees or stone curlews. Large cursorial birds with streaky earth-colored plumage, laterally compressed bill, holorhinal, nostrils pervious, large head, large eyes, long legs with enlarged tibiotarsal joint, 3 short toes, no hallux, middle toenail with inner side of nail dilated, sometimes notched. Dry, open, sandy or stony habitats. Mainly crepuscular and nocturnal. 9 species, 1 genus. Temperate to tropical in Old World, subtropical and tropical in New World.

Glareolidae. Coursers and pratincoles. Coursers are medium-sized plover-like birds with slender, decurved bills, broad wings, long legs, and 3 short toes, middle toenail pectinate in some species. Plumage often with bold patterns on the head or breast. Pratincoles have a swallow-like body form, short wide bill, long pointed wings, short legs, longer front toes than in coursers, middle toenail pectinate, and a short hallux present in most species, sociable and flock all year, feed like swallows on flying insects. Some species are intermediate in form between coursers and pratincoles-- rock pratincoles have longer legs than most pratincoles, cream-colored coursers have shorter legs than two-banded coursers, and Egyptian "plovers" Pluvialis and Australian "dotterel" Peltohyas are even shorter-legged. Schizorhinal (or holorhinal, Egyptian plover), impervious nostrils, culmen curved, tarsus transversely scutellate fore and aft. Open country, often arid lands, some coursers are nocturnal. 17 species, 5 genera. Old World.

Chionidae. Sheathbill. Pigeon-like shorebirds with thick white plumage, saddle-shaped horny sheath covering the base of the short, stout bill. Nostrils holorhinal and pervious, no basipterygoid process or occipital fontanelles, large supraorbital glands, carpal spur present, tarsus reticulate. Intertidal and near-shore scavengers on penguin colonies, beachwrecks, shore animals, also feed on marine algae. 2 species, 1 genus. Antarctic and subantarctic.

Pteroclididae. Sandgrouse. Terrestrial birds of dove-like form with long wings, short bills, plumage in pastel shades of gray, red, yellow, brown, and buff, often marked with black and white, no nasal operculum, tarsus short and partly or completely feathered, hallux small or (Syrrhaptes) absent. Belly feathers of several species are specialized to transport water to the young. Young are downy, remain in nest where fed and watered by the parents. 16 species, 2 genera. Old World: Africa, Madagascar, southern Europe, southern Asia.

Stercorariidae. Skuas. Jaegers are medium-sized and skuas (restricted sense) large coastal marine pirates, gull-like with a hooked bill and a cere, rhamphotheca complex with plates, toes incompletely webbed and with strong curved claws. Sternum with 1 notch on each side (2 in gulls, terns, and skimmers). 8 species, 2 genera. Circumpolar at high latitudes in both hemispheres.

Laridae. Gulls. Medium to large birds of the coasts (some are pelagic when not breeding) with long narrow wings, bill stout in most species, no cere, culmen decurved at tip, plumage typically gray above and white below, the "hooded gulls" with blackish head in breeding season and the white-headed gulls may not be monophyletic groups. Legs short, toes webbed, hallux small (vestigial or lacking in some). 50 species, 6 genera. Cosmopolitan.

Sternidae. Terns. Long slender wings, typically slender, straight bill, plumage in most species gray above and white below, often with black cap in breeding plumage, tail usually forked. Legs short, toes webbed, hallux vestigial. Sternum 2 notches each side. 45 species, 7 genera. Cosmopolitan.

Rynchopidae. Skimmers. Large tern-like bird, plumage blackish above and white below, bill laterally compressed to thin blades, lower mandible longer than upper, the knifelike blade used in plowing the surface of the water. Pupil of eye slit-like. 3 species, 1 genus. Africa, India, southeast Asia, and South America on tropical and subtropical lakes and large rivers, coastal in North America.

Alcidae. Auks. Medium-sized coastal marine diving birds with stocky body build, short wings used together with feet in swimming under water, dense plumage, plumage mainly black, white, and gray, variable bill shape (laterally compressed), rhamphotheca complex and seasonally shed in many species, short legs, 3 webbed toes, no hallux. Skeleton: basipterygoid processes absent; occipital fontanelles present; sternum long and narrow, extends beyond postero-lateral processes. 23 species (1 extinct), 12 genera. Holarctic.

tarsus longer than middle toe, usually scutellate (or booted), bill without tooth or notch; Buteoninae (Buteo hawks and eagles), tarsus shorter than tibia, usually scutellate fore and aft, sometimes feathered to toes, heavier-bodied than accipitrine hawks; Circinae (harriers), feathers soft, sides of head with an incomplete ruff, large opening of ear, long bristles of lores, legs long, tarsus equal to tibia (as in Accipitrinae), wings and tail long; Polyboroidinae, African gymogene or banded harrier-hawk, legs double-jointed, reach into holes, tear apart nests; Circaetinae (Old World booted eagles, snake eagles, harrier eagles, bateleur), tarsus with heavy-duty scales, short rough toes for grasping snakes; Aegypiinae (Old World vultures, palm-nut vulture = "vulturine sea eagle", lammergeier), large, heavy bodied, many scavenge on ungulates, adults usually with bare heads, often with neck ruff, superciliary plate absent; Pandioninae (osprey), large, diurnal fish-eating hawk with stout tarsus, spiny feet and long curved claws, the outer toe reversible in life, hypotarsus of the tarsometatarsus with a bony ring for foot tendons, and coracoids overlap at the sternum. "Eagles" and "kites" are morphological forms, not distinct monophyletic lineages. Certain hawks and eagles are of uncertain relationships, some of these subfamilies may be paraphyletic, and molecular studies are in progress. 221 species (1 extinct), 60 genera, the subfamilies above are characterized mainly by skeletal features, also by molt patterns. Cosmopolitan.

Sagittariidae. Secretary-bird. Long-legged, cursorial raptor, crown of spatulate feathers, long central tail feathers, legs feathered to intertarsal joint, toes webbed at base. Skeletal features unusual or unique to this family in the order include basipterygoid process present, clavicles broadly attached to sternum, uncinate processes reduced, and tarsometatarsus laterally compressed. 1 species. Africa.

Falconidae. Falcons and caracaras. Diurnal raptors with sharp talons and hooked bill, toothed in falcons, nostril small and circular (falcons) or slit-like (caracaras), with a small tubercle (nostril large and broadly oval in forest falcons Micrastur), skull differing from hawks including ossified nasal region and fused thoracic vertebrae (except laughing falcon Herpetotheres). Other skeletal features are desmognathous palate, vomer expanded anteriorly, a prefrontal plate over the orbit, and the first and second bronchial semirings with a large oval gap between them. Molt sequence differs from accipitrids in starting from three loci: primary 4 (proceeding inward and outward), secondary 5 (proceeding inward and outward) and the innermost secondary (in accipitrids, molt as in most birds begins with innermost primary and proceeds outward, in "descending mode"), and with 2 or 3 foci in the secondaries. Typical falcons have long, pointed wings, caracaras have bare area on the head and are both predators and scavengers. Falcons use holes, caracaras build their own nest. 63 species, 10 genera, 4 subfamilies. Cosmopolitan (laughing falcons, forest falcons, and caracaras Neotropical).

Cathartidae. New-World vultures or condors. Large soaring birds with black or dark brown plumage, unfeathered usually brightly colored heads (adults), bill hook-like, nostrils externally perforate, legs stout, toes thin, claws short, hallux small and elevated, basal web between toes 2 and 3. Skull holorhinal, palate indirectly desmognathous, maxillopalatines widely separated but co-ossify with medial nasal septum, maxillopalatines in form of scroll-like plates, vomer absent, pterygoids twisted, basipterygoid process present, sternum entire (not notched on posterior surface), some of these features as in storks. 7 species, 5 genera. New World.


Pelicans and allies. Large water birds with four toes with a common web (totipalmate foot), many with a bare gular sac, and all but tropicbirds with no exposed external nares (=nostrils obsolete). In contrast to petrels and loons, the skull lacks a supraorbital groove for a nasal gland. Palate desmognathous (except Phaethontidae), dorsal vertebrae opisthocoelous. They breed in colonies. The monophyly of this group is questioned; frigatebirds may be related to petrels.

Phaethontidae. Tropicbirds. Pelagic. Tarsus short, feet small. Bill straight, not hooked, edges serrate. Palate schizognathous. Plumage satiny white and black. Middle rectrices extremely long. Gular region entirely feathered. Plunge-dive from the air. 3 species, 1 genus. Warm tropical and subtropical oceans.

Sulidae. Gannets and boobies. Pelagic and inshore marine birds. Feet totipalmate, bill stout, some serrated, pointed, slightly curved near tip, no external nostrils, a nasal groove runs along the bill. Bare gular skin. Plumage white, gray, brown, and/or black. Tail long and pointed. Plunge-divers, they hover then plunge into water after fish. 9 species, 3 genera. Oceanic, gannets are temperate, boobies tropical and subtropical.

Phalacrocoracidae. Cormorants. Large swimming birds (freshwater and marine inshore). Feet totipalmate, bill slender, cylindrical, hooked, nostrils obsolete. Small gular sac and face unfeathered, often brightly colored in life. Plumage often iridescent blackish. Swim often with only the neck emerging, and dive from the surface to fish. 38 species (1 extinct), 1 genus. Worldwide.

Anhingidae. Darters or anhingas. Large swimming aquatic bird, mainly freshwater. Feet totipalmate, bill slender, straight, sharply pointed, nostrils obsolete. Small bare gular sac. Legs short. Tail long, with a fluted or washboard form. Enlarged ventral keel on cervical vertebrae 5-7 for attachment of muscles that project the bill forward like a spear. Feed by swimming slowly under water and ambushing their prey fish. 4 species, 1 genus. Worldwide at lower latitudes.

Pelecanidae. Pelicans. Large aquatic birds (freshwater and marine, inshore), feet totipalmate, bill very long, straight, and hooked. Large gular sac and face unfeathered. Plumage white, brown, or gray. Draw their heads back in flight. One species feeds by plunge-diving, others dip the bill while swimming on the surface or pursue prey under the surface, sometimes in cooperative groups. Clavicles fused to sternum. 8 species, 1 genus. Cosmopolitan.

Fregatidae. Frigatebirds. Large aerial birds of tropical seas. Plumage brownish black, iridescent, some with white below. Feet small, totipalmate at the base of the toes. Throat bare, gular sac brightly colored and greatly enlarged when inflated in breeding males. Bill long, cylindrical, strongly hooked at tip. Wings long and pointed, tail long and forked. Coracoid and furcula are fused to the sternum, unique in birds. Skim the surface of the sea, also pirate food from other birds in flight. 5 species, 1 genus. Tropical and subtropical oceans, especially where flying fish occur.


Storks and related birds--long-legged wading birds. Herons are the most speciose group. Middle toenail is laterally expanded in all, and comblike or pectinate in some families.

Ardeidae. Herons. Long-legged wading birds, long neck, pectinate middle toenail, powderdown patches, bill spearlike in most forms. Plumage varied, uniformly colored in most egrets, broadly barred in certain plumages in tiger herons, streaked in most bitterns, plumes in breeding season in many forms. 61 species, 17 genera. Worldwide.

Scopidae. Hammer-headed stork or hamerkop. Crested, brown wading bird with laterally compressed bill and short legs, pectinate middle toenail, no powderdown. 1 species. Africa.

Ciconiidae. Storks. Large wading birds with long legs and long, stout bill, curved near tip in some species, head sparsely feathered or bare in some species. Middle toenail entire. 19 species, 6 genera. Cosmopolitan, mainly tropical and subtropical.

Balaenicipitidae. Shoebill or whale-headed stork. Huge head and bill shaped like a wooden shoe. Like pelican, it has broad palate, groove in bill, clavicles fused to sternum, and other pelican-like skeletal characters, and some molecular studies suggest it is related to pelicans not to storks. 1 species. Equatorial swamps in east Africa.

Threskiornithidae. Ibises and spoonbills. Medium to large wading birds with long legs, either (ibis) with a long, slender, grooved, and decurved bill, or (spoonbills) with a flattened spatulate bill. Middle toenail entire, not pectinate. Plumage variable--white, brown, black (pink or red in two tropical species). 34 species, 14 genera. Cosmopolitan.

Order Phoenicopteriformes

Phoenicopteridae. Flamingos. Large wading birds with thick bill bent down near midpoint and lamellate filters. Middle toenail entire. Plumage pinkish, flight feathers black. Filter feeders, straining tiny plants or animals from the water. Young with two sets of natal down plumage like penguins and procellariiforms; while the feathers and tongue are like waterfowl and in behavior they flock and call like geese; and the skeleton is more like storks. Colonial breeders. Tropical and subtropical (to temperate region in Asia and South America), all continents. 5 species, 1 genus.


Tube-nosed seabirds, with an external nasal tube on the horny covering of the bill, and a hook at end of bill. Skull has a conspicuous supraorbital groove for nasal gland. Feed on fish, squid and zooplankton. They feed their young with regurgitated oil, derived from food sometimes caught more than a thousand km from the nest site. Oceanic.

Diomedeidae. Albatross. Large soaring pelagic birds, stout, hooked bill with plates and two unfused tubular nostrils separated by culmen. Legs short, hallux reduced or absent, front three toes webbed. Plumage white, grays and browns. Glide on long, narrow wings, spend their lives at sea, seldom seen from mainland. 14 species, 2 genera. Oceanic, breed mainly on islands in the Southern Ocean.

Procellariidae. Shearwaters and petrels. Medium to large soaring pelagic birds with tubular nostrils joined on top of bill and separated only by a septum (recessed in fulmars). Plumage white, grays, and browns, some nearly black. Bill variable, hooked, with horny plates; lamellae in prions Pachyptila used in filter-feeding. Legs short, hallux reduced, front three toes webbed. Wings broader than albatross but (most species) narrower than gulls, alternate rapid, shallow wingbeats with stiff-winged glides. 76 species, 14 genera. Oceanic, worldwide.

Hydrobatidae. Storm-petrels. Small to medium-sized pelagic birds with a single tube joining the nostrils. Bill slender, grooved, hooked. Toes webbed, hallux minute. Plumage blackish with white on rump or underparts in many species. Fluttery wingbeat, patter on the ocean surface. 21 species (1 extinct), 7 genera. Oceanic, worldwide.

Pelecanoididae. Diving petrels. Small marine birds, dive from the air or from surface into water where they swim under water with their wings in pursuit of prey, like small alcids. Tubular nostrils point upward, no hallux, plumage black above and white below, short bill, wing, and tail. 4 species, 1 genus. Southern Ocean.

t three toes individually lobed, nails flat and broad, hallux present in most, absent in some species. Tarsus laterally compressed. Legs insert far behind middle of body. Plumage thick, waterproof, and satiny in texture. Food varies with bill shape. Rarely come to land, they nest on floating vegetation. Courtship behavior is spectacular, in some species with pairs dancing belly to belly as they balance upright on the water surface, or dancing side-to-side in a forward rush. 3 species are flightless (2 of these are extinct). 21 species (2 extinct), 6 genera. Cosmopolitan.


Perching birds. The largest order of birds, it includes more than half of all species. Passerines are characterized by small size, terrestrial lifestyles, and a complex syrinx. Morphologically they are characterized by: palate aegithognathous, a tensor propatagialis brevis tendon running from pectoral to patagium to humerus, sperm bundles with coiled heads, hallux large, deep plantar tendons type VII, and M. pubo-ishio-femoralis which divides into pars cranialis and pars caudalis. Other more conspicuous features are shared in common with other orders and are not uniquely derived in this order: foot anisodactyl, hallux incumbent, and wing eutaxic.

Suborder 1New Zealand wrens

Acanthisittidae. New Zealand wrens. Very small, long legs, short tail, greenish upperparts. Lacks a typical oscine syrinx: the location of the syrinx is bronchial (tracheobronchial in songbirds) and it has no intrinsic muscles (Ames 1971). New Zealand wrens lack a typical suboscine inflated stapes, the stapes is unique though much like the oscine stapes. DNA-DNA hybridization results (Sibley & Ahlquist, 1990, fig. 186) showed the greatest similarity (among ten passerine birds tested) with a songbird (bowerbird), and the least with two Old and New World suboscines (pitta, Tyrannid flycatcher), though Sibley & Ahlquist (1990) in text and tapestry grouped New Zealand wrens with suboscines. One species recently extinct was perhaps flightless. 4 species (1 extinct), 2 genera. New Zealand.

Suborder 2. Suboscines

Old World Suboscines - stapes (columella, inner earbone) expanded, much as in kingfishers.

Eurylaimidae. Broadbills. Short, broad, inflated bill; see also "Philepittidae." Plumage with gaudy purples, blues, and greens. Deep plantar tendons are linked by a vinculum band between tendon flexors of toes 1 and 2. Includes "Philepittidae," the asity and false sunbirds of Madagascar, small and long slender decurved bill (false sunbird), or medium-sized with short straight bill wide at base and velvety plumage (asity), and facial wattles. Certain broadbills and the philepittas are similar in structure of the syrinx, sternum, and pterylosis. 18 species, 10 genera, Old World Tropics.

Pittidae. Pittas. Brightly colored, thrush-like birds with long legs, short tail. 29 species, 1 genus. Old World Tropics, mainly Indomalayan.

New World Suboscines

Furnari: ovenbirds and antbirds, etc. -- stapes expanded, much as in kingfishers (ref: Feduccia 1985); syrinx tracheophone (ref: Iresedt et al. 2002)

Furnariidae. Ovenbirds. Includes ovenbirds Furnarius and Gymnopithys, miners Geositta, earthscrapers Upucerthia, spinetails Synallaxis, foliage-gleaners Philydior, nuthatch-like Xenops, leaftossers Sclerurus, thornbirds Phacellodromus, and firewood-gatherer Anumbius. Morphologically diverse group of birds with brown plumage, often rufous or chestnut. Includes the woodcreepers and scythebills Dendrocolaptinae, birds with brown plumage, bill straight or decurved, rectrices stiff, feet strong, tarsus typically endaspidean (49 species, 13 genera). Syrinx with 2 pairs of intrinsic muscles. Synallaxis appears to be basal to the other genera, and stiff rectrices may be plesiomorphic in the family. 280 species, 60 genera. Neotropical.

Formicariidae. Antbirds including forms with sternum 2-notched (ant-thrush, Formicarius, Chamaeza) or 4-notched, in the ground dwelling forms (including antpittas Pittasoma, Grallaria, Grallaricula). Loose-plumaged, tail usually short, bill often hooked and swollen. 56 species, 7 genera, not including Conopophagidae and Thamnophilidae. Neotropical.

Conopophagidae. Gnateaters. Small, long-legged birds with short rounded wings, brown and gray plumage, white ear patch; palate schizognathous, 4-notched sternum. 8 species, 1 genus Conopophaga. Neotropics.

Rhinocryptidae. Tapaculos. Brown ground-living birds with large nostril and operculum, sternum 4-notched, syrinx with 1 intrinsic muscle (lacking in Teledromas gallito). Crescent-chest Melanoparia is usually included in Rhinocryptidae, but molecular genetics suggests it is basal to all Furnari (Iresedt et al. 2002). 28 species, 12 genera. Neotropical.

Thamnophilidae. "Typical" antbirds, syrinx with 1 pair of intrinsic muscles, sternum 2-notched, including many antbirds, Myrmotherula ant-wrens, Dysithamnus antvireo, Taraba and Thamnophilus antshrikes. 188 species, 45 genera. Neotropical.

TyranniNew World flycatchers, cotingas and manakins

Cotingidae. Cotingas. Typically medium-sized to large fruit-eating birds, bill broad with a hook, plumage often bright, some with crests or wattles, some with powderdown (unique among suboscines). Tarsus typically with fine scutes posteriorly, scutellation variable; not exaspidean. Toes syndactyl. Lek behavior in several species, sexually dimorphic in size and plumage in most. Includes the plantcutters Phytotoma, formerly called a family Phytotomidae. 68 species, 27 genera. Neotropical.

Pipridae. Manakins. Small, stocky birds with short bills, broad at base and slightly hooked. Tarsus exaspidean, toes syndactyl. Short tail. Lek behavior with notable displays, males take no part in parental care. Males use the short, curved outer primaries (found in both sexes in lekking display. Machaeropterus has outer primaries thick and twisted for sound production. 52 species, 16 genera. Neotropical.

Tyrannidae. Tyrant or New World flycatchers, in the broad sense including Corythopis antpipt and others mentioned below. Typically with bill broad at base and rictal bristles, but the bill form varies. Tarsus exaspidean, toes not syndactyl. Uncertain whether the family is monophyletic; some species groups are recognized as families "Mionectidae" and "Tityridae." As presently understood (AOU 1998), the family includes the following subfamilies: Elaiinae, tyrannulets (including Camptostoma, Elaenia); Platyrinchinae (pygmy-tyrants, flatbills, Todirostrum tody-flycatchers, spadebills); Fluvicolinae (royal flycatcher, Contopus pewees, Sayornis phoebes, Empidonax, vermillion flycatcher); Tyranninae (Attila, Myiarchus, Pitangus kiskadese, Myiodynastes sulphur-bellied flycatchers, Tyrannus kingbirds); and "incertae sedis" (perhaps flycatcher, perhaps not): Sapaoya, Schiffornis "thrush-like manakin", Lipaugus rufous piha, Pachyramphus becards, Tityra tityras. Further work may P>Shufeldt, R.W. 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences, 19, 1-109.

Sibley, C. G. & J. E. Ahlquist. 1984. The relationships of the starlings (Sturnidae: Sturnini) and the mockingbirds (Sturnidae: Mimini). Auk 101:230-243.

Sibley, C. G. & J. E. Ahlquist. 1987. Avian phylogeny reconstructed from comparisons of the genetic material, DNA. in Molecules and morphology in evolution: conflict or compromise, ed. C. Patterson. Pp. 95-121. Cambridge Univ. Press.

Sibley, C. G. & J. E. Ahlquist. 1990. Phylogeny and Classification of Birds, A Study in Molecular Evolution. Yale Univ. Press. (as in pp. 605-627)

Sibley, C. G., Ahlquist, J. E. & Monroe, B. L. 1988. A classification of the living birds of the world based on DNA-DNA hybridization studies. Auk 105:409-423. (see p. 413)

Stinson, C. M. 1993. A survey of variation in the humeral fossa of passerine birds and its implications for systematics. MS thesis, University of Louisville.


Menuroidea &endash; lyrebirds and scrub-birds

Menuridae. Lyrebird. Large songbirds, huge feet, the songbird most like a pheasant, elaborate tail feathers in the male. Syrinx with few (3 vs. 4) intrinsic muscles. Elaborate loud song with mimicry of many bird species, also dogs, trains, etc. shared among neighbors. 2 species, 1 genus. Australia.

Atrichornithidae. Scrub-bird. Terrestrial birds with brown plumage, finely barred. Syrinx with few (3) intrinsic muscles. Songs loud, shared among neighbors and may change year to year (A. clamosus). Clavicles minute, unfused, pectoral muscle reduced, flies weakly. 2 species, 1 genus. Australia.

Old Australian endemics (not a clade)

Ptilonorhynchidae. Bowerbirds. Thrush- to crow-sized birds, stout legs, plumage often brilliant or ruffed. Males build display bowers and mate in the bower, and females alone rear the young, except in Australasian catbirds Ailuroedus. Includes extinct New Zealand "thrush" Turnagra. 20 living species, 7 genera. Australia and New Guinea.

Climacteridae. Australian treecreepers. Feet large, especially the hallux, claws strongly curved. Bill long, slightly decurved; feet syndactyl. Tail rounded, rectrices not stiff. Plumage brownish, flight feathers with a paler bar. 7-8 species, 1 genus. Australian Region.

Maluridae. Australian wrens: fairy-wrens Malurus, emu-wrens Stipiturus, grasswrens Amytornis. Small songbirds with long tail sometimes cocked over back, 10 tail feathers in grasswrens, 8 (+2 very short) in fairy-wrens, 6 in emu-wrens. Pendant pseudogenitalia in adult males. Nasal operculum in grasswrens. Social organization variable, cooperative parental care and extra-group matings (perhaps most fertilizations are by a male in another social group) in species where behavior has been observed. 26 species, 5 genera. Australia and New Guinea.

Pardalotidae. Australian warblers, including bristlebirds, pardalotes, scrub-wrens, thornbill, whiteface, flyeaters and pardalotes. Small songbirds of no known distinctive morphological features, but distinct from northern songbirds in their DNA. The genus name Pardalotus has priority over Acanthiza, so the family name Pardalotidae has priority over Acanthizidae. 68 species, 16 genera. Australian Region including New Guinea and New Zealand, flyeaters Gerygone to Malaysia and the Philippines.

Meliphagidae. Honeyeaters. Brush-tongued nectar-feeding birds typically; some are mainly fruit eaters or insect eaters. Size and form quite variable; face often with bare areas (some with wattles), bill often decurved, plumage brown and yellow. Includes "Ephthianuridae" Australian chats, bill short and slightly decurved, tail short, ground birds with a brush-tipped tongue. Apalopteron and Cryptornis are now regarded as white-eyes, not honeyeaters. 181 species (3 extinct), 41 genera. Australasian region including Pacific islands; 2 genera [1 extinct, the other rare] in Hawaii).

Eopsaltriidae. Australo-Papuan robins and scrub-robins (Eopsaltria, Petroica, Drymodes, Tregellasia). Small birds, chat-like, long-legged, plumage yellow or red below, the group is characterized by its DNA-DNA hybridization indices and (Tregellasia) nuclear gene sequence; formerly regarded as Old World flycatchers or thrushes. 46 species, 14 genera. Australia and New Guinea.

Orthonychidae. Log-runners or chowchillas Orthonychus. Terrestrial forest birds with spine-tails, and plumage streaked or scaly-patterned brown above. 2 species, 1 genus. Australia and New Guinea.

Pomatostomidae. Australian babblers Pomatostoma. Group-living birds with decurved bills and long legs, morphologically similar to Asian and African babblers, but distinct in DNA-DNA hybridization index and in nuclear gene sequence. 5 species, 1 genus. Australia and New Guinea.

Cinclosomatidae. Quail-thrush Cinclosoma, whipbird, and rail-babblers. Medium-sized, long-tailed, mainly terrestrial birds with cup-shaped nests. A DNA family, not previously recognized on morphological characters. Ifrita kowaldi of New Guinea is toxic; its relationships are uncertain, though it seems not to be closest to the other known toxic bird, Pitohui. 15 species, 6 genera. Australian region; Eupetes is Indomalayan (Borneo to Malaya).

Corvoidea - crows, birds of paradise, and related families

Melanocharitidae. Berrypeckers. The berrypeckers Melanocharis, Rhamphocharis, Paramythia and Oreocharis, and the once-"honeyeaters" or longbills Oedistoma and Toxorhamphu. Small nectar-feeding birds recognized in DNA-=DNA hybridization and in nuclear gene sequence (some species known), differ from dicaeids in nest structure (an open cup, where known), in lack of specialized structure of the tongue, and in molecular genetics (DNA-DNA hybridization and nuclear gene sequence) from the dicaeids. Bill slightly serrate in Melanocharis and Toxorhamphus. 12 species, 6 genera. New Guinea.

Campephagidae. Cuckoo-shrikes. Lax-plumaged birds with thick-shafted back feathers that are loosely attached to the skin. Plumage often gray, often barred, sometimes glossy black, bill notched in some species, broad at base and curved along culmen, in minivets the bill small and plumage with reds or yellows. 70 species, 9 genera. Old World.

Vireonidae. Vireo, pepper-shrike, shrike-vireo. Plumage green, gray, or brown, bill slightly notched, large and hooked in pepper-shrikes and strongly notched in shrike-vireos. Formerly regarded as in the "New World nine-primaried" assemblage, the presence and size of the outer (tenth) primary variable among species of Vireo. 51 species, 4 genera. New World.

Corvidae. Crows and jays. Middle-sized to large songbirds with strong, straight bills and stiff feathers over the nostril (stiff feathers lacking in piñon jay and adult rook). Plumage black in typical crows, blues and greens in some jays, some with crest. Ground jays in China Podoces, one Pseudopodoces may be a tit not a crow. 113 species, 23 genera. Cosmopolitan.

Paradisaeidae. Birds-of-paradise (20 genera) and Melampitta. Large, arboreal fruit-eating birds, including the monogamous and monomorphic manucodes, the dispersed-arena species with males with loud calls, and the lekking species with males of large body size, bright plumage colors, and ornate plumes. 45 species, 21 genera. Australia and New Guinea, 2 genera in N Moluccas.

Cracticidae. Australian butcherbirds Cracticus, Australian magpie Gymnorhina, currawong Strepera, peltops flycatcher Peltops, and Bornean bristlehead Pityriasis. Thick bill often hooked on end, blackish plumage, and similar DNA-DNA thermal indices. 13 species, 5 genera. Australia and New Guinea, Pityriasis in Borneo.

Callaeidae. Wattlebirds. Kokako Callaeas, saddleback Creadion, huia Heterolocha. Medium to large brown and gray birds with large fleshy wattles at base of bill, short wings with long outer primaries. Relationship to other songbird families is uncertain. 3 species (1 extinct, huia), 3 genera. New Zealand.

Corcoracidae. Australian chough Corcorax and Apostlebird Struthidea. Large, terrestrial group-living songbirds building nests of mud. 2 species, 2 genera. Australia.

Grallinidae. Magpie larks. Black and white ground-feeding birds with broad wings, with nests of mud. 2 species, 2 genera. Australia and New Guinea.

Pachycephalidae. Sittellas Daphoenositta, shrike-tits Falculculus, shrike-thrushes Colluricincla, thickhead whistlers Pachycephala, pitohuis Pitohui (including a species with toxic skin and feathers) and New Zealand Mohoua and Finschia. Large-headed birds, some with large or deep bills, and loud calls and songs, and with similar DNA-DNA thermal indices. Many were formerly considered Old World flycatchers. 46 species, 9 genera. Australasian.

Oriolidae. Orioles. Arboreal birds with long, slightly decurved bill, the plumage often with yellow and green. 28 species, 2 genera. Old World.

Dicruridae. Drongos. Plumage black (gray in one species), usually glossy, with spangles, hackles, or curled form, bill broad at base, tail typically long and forked, 10 tail feathers (12 in one species), jay-like bill. 20 species, 2 genera. Old World.

Rhipiduridae. Fantails (part of former "Muscicapidae"). Flycatchers with flattened short bills, rictal bristles, long tails, and small heads. 42 species, 3 genera. See Sibley and the Dictionary for African genera perhaps in this group. Old World, mainly Indo-Pacific.

Monarchidae. Monarch flycatchers (part of former "Muscicapidae". Arboreal birds with laminiplantar tarsus, flat bills, rictal bristles, large heads, some with long tails, plumage often and social behavior with allopreening and clumping. 10 species, 1 genus. Australian region, Indo-Pacific to southern Asia.

Aegithinidae. Ioras. Small yellow and black birds with a pointed bill, insectivorous and nectarivorous. 4 species, 1 genus. Southern Asia from China and India to Borneo and the Philippines.

Passerida (clade includes all the following oscines)

Picathartidae. Rockfowl and rock-jumpers. Long-legged jumping songbirds. Picathartes, rock- and cave-nesting forest birds in West Africa (formerly called corvids or babblers; breeding is sometimes colonial); Chaetops, rock-jumping birds of scrub in rocky southern Africa (formerly called babblers or warblers; breeding is sometimes cooperative). Genetically distinct from other songbirds, basal to Passeroidea. The skeleton (humerus, pneumatic fossa) of Picathartes is similar to corvids; the humerus of Chaetops has a single cup-like fossa but the bone is not pneumatic. 4 species, 2 genera. Africa.

Bombycillidae. Waxwings. Brown plumage, crested, broad short bill, fruit-eaters. 8 species, 4 genera. Holarctic. Includes subfamilies Ptilogonatinae, silky flycatchers, with silky plumage, black, gray, and yellow colors, crested. 4 species, 3 genera, Neotropical; and Dulinae, palmchat, plumage similar to juvenile waxwing, colonial nesting in a compound nest, 1 species, Hispaniola (West Indies).

Paridae. Tits. Small birds with slender bills, nostrils covered with bristles, plumage unstreaked, often with black and white head pattern. 54 species, 3 genera. Holarctic (one to southern Mexico), Indo-Malayan and Africa.

Sylvioidea - Old World warblers and allies

Sylviidae. Old World warblers. Small insectivorous birds with thin bills, thin tarsus, and unspotted juvenile plumage. Palearctic warblers include the Sylvia species with the bill not compressed, culmen more or less curved and rictal bristles little-developed, Phylloscopus warblers with the bill slim, pointed, shorter than head (largest genus with about 41 species), bill slender in marsh-living Acrocephalus, and bill flat and wide in Hippolais. Genera vary in degree and number of rictal bristles (2 in Schoenicola, 3 in Acrocephalus, 5 on a flap of skin to cover the eyes in bristled grass warbler Chaetornis), in relative length of tail feathers and primaries, in form of toes (inner and middle deeply cleft in Megalurus, with inner toe partly reversible), in shape of bill (long and flat in Asian tailorbirds Orthotomus and African longbills Macrosphenus, short and flattened in flycatcher-warblers (Seicercus with 12 rectrices and Abroscopus with 10 rectrices in India and Hyliota in Africa); and in form of tail (long and graduated in Megalurus with 12 rectrices, soft-plumaged and 10 broad rectrices in Cettia,12 or 10 in Nesillas, 12 or 10 in "Prinia", loose-webbed in Madagascar emu-tails Dromaeocercus with 8 rectrices, and New Zealand fernbird Megalurus (Bowdleria) punctatus), short in African nuthatch-warblers Sylvietta and Asian ground warblers Tesia). 368 species, 61 genera (this figure includes the Cisticolidae and Hyliidae, now thought not to be sylviids; and includes some birds that do not clearly occur on the mtDNA tree with other warblers, including Acrocephalus). Old World, mainly Palearctic and African; 2 genera Phylloscopus (one species) and Chamaea in New World.

Cisticolidae. Grass-warblers and forest warblers. The grass-warblers Cisticola with 50 species, Prinia with 27 species, Hypergerus and Eminia with long and decurved bill, and other genera include several African, Madagascar and Asian forest "warblers" listed above in "Sylviidae"), with Macrosphenus, Camaroptera and Apalis in Africa, Orthotomus, Tesia in Asia, and Dromaeocercus, Neomixis, Cryptosylvicola, Thamnornis and Oxylabe, in Madagascar, among others, are in this clade, which is recognized in molecular genetics. Old World.

Hyliidae. Hylias. Small songbirds, morphologically distinguished by forked tongue and long, flat hyoid bones. Hylia is a short-tailed whistling forest warbler with a stout bill; Pholidornis tiny tit-weaver was formerly considered an estrildid finch, a tit, and others. 2 species, 2 genera. Africa.

Pycnonotidae. Bulbul. Plumage soft and fluffy, with long bare hair-like feather shafts on nape (including Neolestes), rictal bristles, plumage colors often greenish or yellowish, bill usually slender. Family may include Hypocolius. 137 species, 21 genera. Old World (Africa, Asia).

Zosteropidae. White-eyes. Bill slender and slightly decurved, tongue brush-tipped, plumage usually yellowish, 9 primaries (or 10th primary small), typically with whitish feathered ring or bare skin around eye, and operculum over the nostril. Loss of yellows (carotenoids) in color phases in some species and in several island species. Cleptornis on Saipan and Apalopteron on Bonin / Ogasawara Islands were once "honeyeaters", but now are white-eyes based on DNA-DNA thermal hybridization studies. Island species are often large in body size (Speirops, Cleptornis, Apalopteron, Woodfordia, Heleia, Rukia). 97 species (1 extinct), 14 genera. Old World, prominent on Indo-Pacific islands.

Alaudidae. Larks. Ground birds with long, straight claw on hallux, lack an ossified pessulus in the syrinx, tarsus holaspidean, posterior surface of tarsus rounded, covered by scutes, plumage usually brown. 91 species, 17 genera. Cosmopolitan, most species in Africa, 1 (+1 introduced skylark) also in New World, 1 in Australia.

Hirundinidae. Swallows. Aerial specialists feeding on insects on the wing. Bill short and flattened, gape wide, wings long and pointed, bronchial rings complete--in contrast to all other oscines (semi-rings in Old World river martins Pseudochelidon). 89 species, 14 genera. Cosmopolitan.

Remizidae. Penduline tits Remiz, Anthoscopus, Cephalopyrus. Small, slender bill, build a domed nest. 11 species, 3 genera. Old World.

Aegithalidae. Long-tailed Tits. Small, tiny bill, long tail, build a domed nest, group-living and cooperative breeding. 8 species, 3 genera. Palearctic Aegithalos and New World (mainly Nearctic) Psaltriparus; Indonesian Psaltria relationships obscure, perhaps a tit.

Muscicapoidea - thrushes and allies

Regulidae. Kinglets (Regulus). Small songbirds with short straight bill and dense plumage. Formerly considered sylviid warblers, but not closely related in molecular genetic sequences. 6 species, 1 genus. Holarctic.

Cinclidae. Dippers. Stocky birds with a short tail, undercoat of down, operculum over nostril. Walks, swims, and feeds under running water. 5 species, 1 genus. Montane areas of New World, Palearctic, and Indomalayan.

Timaliidae. Babblers. Lax dorsal plumage, often uniformly colored; body form variable, tend to be heavy-bodied, the tarsus fairly large and stout and not booted and the bill not flat, the wings usually rounded, and the juvenile plumage unspotted. Most live in social groups. Pomatorhinus and Xiphirhynchus scimitar-babblers have long decurved bills. Stachyris tit-babblers have an operculum over the nostril, Rhopocichla has partly-perforate nostrils (seen in skull), Myzornis is a nectar feeder with a brush-tipped tongue. Pnoepyga wren-babblers (4 species) have 6 rectrices, Spelaeornis wren-babblers have 10 rectrices. Turdoides babblers of Asia and Africa (26 species) are large jay-like birds with cooperative breeding, Garrulax laughingthrushes (48 species) are Asian. Yuhinia range well north into Asia and have a crest. Trichastoma are terrestrial, long-legged, bristle-faced forest birds in India and Africa, Pellorneum (Asia) are similar but lack bristles, Alcippe tit-babblers have nostrils covered by a membrane: all these groups have short round wings. Panurus bearded reedling (bearded "tit") of Palearctic extends into Europe and is related to the Asian Conostoma and Paradoxornis parrotbills, some in montane bamboo zone, some have thick bill that crushes reeds and bamboo for insects inside, others feed on buds. Family may include Rhabdornis Philippine "creepers". Pteruthius shrike-babblers (hooked bill) are perhaps related to shrikes not to babblers. Babblers are probably paraphyletic, molecular genetic studies are in progress. 272 species, 50 genera. Old World - Asia, Africa and Madagascar.

Turdidae. Thrushes (including Chlamydochaera), robins, chats, wheatears. Tarsus booted in most species, bill slender, juvenal plumage typically spotted. The smaller, short-billed chats often have tarsus long, slender, and scutellate, juvenal plumage unspotted, and conspicuous rictal bristles. Turdidae and Muscicapidae have a unique arrangement of internal muscles of the syrinx (except in African ant-thrushes and North American solitaires). 300 species (1 extinct), 46 genera. Cosmopolitan.

Muscicapidae. Old World flycatchers. Bill broad and flattened, rictal bristles present, legs short. As now conceived the family is much reduced from Mayr's version which had over 1,000 species; certain birds once included are now in Pachycephalidae, Rhipiduridae, Monarchidae, Platysteiridae, Cracticidae, Pardalotidae, Sylviidae, etc. 117 species, 19 genera. Old World.

Mimidae. "Mocking-thrush" group includes mockingbirds, catbirds, thrashers, and West Indies tremblers. Thrush-like birds with scutellate tarsus, often with a decurved bill. 34 species, 10 genera. New World.

Sturnidae. Starlings, mynahs, oxpeckers. Strong legs and bill, the bill slightly curved (unlike icterids), plumage iridescent in many species, tenth primary variably developed. 114 species (2 extinct), 27 genera. Old World.

Troglodytidae. Wren. Small insectivorous birds, typical wrens with barred brown feathers. Includes Donacobius, and the gnatcatchers Polioptila, gnatwrens Microbates, and verdin Auriparus as a subfamily Polioptilinae. 90 species, 20 genera. New World, 1 species into Palearctic.

Sittidae. Nuthatches Sitta, wallcreeper Tichodroma. Treetrunk and rock-foraging birds with unstreaked plumage, stout feet, large toes, and a chisel-like bill with angled gonys. 25 species, 2 genera. Holarctic, also 4 species to South-east Asia.

Certhiidae. Treecreepers Certhia, spotted creeper Salpornis. Treetrunk foraging, small brownish birds, streaked above, bill slender and decurved, long curved claws, and stiff pointed tails. 7 species, 2 genera. Holarctic, Africa, southern and southeastern Asia.

Old World nectar feeders

Irenidae. Fairy-bluebirds. Fruit-eating forest birds, plumage blue. 2 species, 1 genus. Indomalayan Region.

Chloropseidae. Leafbirds Chloropsis. Insectivorous, bill straight or decurved, tarsus slender, plumage green with yellow and black. 8 species, 1 genera. Indomalayan Region.

Nectariniidae. Sunbirds. Nectar-feeding birds, bill slender, usually decurved, slightly serrated edges, plumage often brightly colored and sexually dimorphic, tongue with tube-like longitudinal trough and tip bifid or trifid. Pollenators of flowers; short-billed Anthreptes cheat on pollenation, take nectar by piercing flower corolla at the base. Long-billed spiderhunters Arachnothera eat insects and spiders. 117 species, 4 genera. Old World, mainly Africa.

Promeropidae. Sugarbird. Nectar-feeding, long decurved bill, long tail, streaked brown and yellow plumage, tongue laterally rolled into an open tube, fringed at tip and along sides. 2 species, 1 genus. Southern Africa.

Dicaeidae. Flowerpeckers. Small nectar-feeding and berry-eating birds with short bills, short tails, brown, red, and yellow plumage, and tube-like tongues. Nest a hanging covered structure. 42 species, 2 genera (excluding pardalotes, which are now Australian warblers; and berrypeckers, now Melanocharitidae). Australasia.

Passeroidea &endash; sparrows and allies

1. Old World sparrows and allies

Motacillidae. Wagtails, pipits, and longclaws. Ground birds with long hallux and long claw, bill slender, nostrils perforate. Plumage streaked brown in pipits, solid colors of black, white and yellow in wagtails, and both in longclaws. 65 species, 5 genera. Cosmopolitan.

Prunellidae. Accentors. Small terrestrial gray and brown birds with slender, pointed bill, nostril operculate. Mating system variable within a population. 13 species, 1 genus. Palearctic.

Passeridae. Sparrows. Sparrow-billed birds (Old World sparrows Passer, snow-finch Montifringilla, pale rock-finch Carpospiza, rock sparrows Petronia) with outer primary slender, minute and dorsal, and with a neomorph bone in the tongue. 36 species, 4 genera. Africa, Palearctic, and Indomalayan; Passer domesticus introduced worldwide.

Ploceidae. Weaver finches. Thick-billed birds with 10 primaries (the outer one ventral and usually small, but large in buffalo-weavers), with thatched grass or thornbranch nests in buffalo-weavers Bubalornis and Dinemellia, sparrow-weavers Plocepasser, Pseudonigrita and Histurgops, sociable weaver Philetarius, and scaly-weavers Sporopipes, and with woven nests in the weaver finches Amblyospiza , Ploceus, Malimbus, Foudia and Quelea, and the bishops and long-tailed widows Euplectes. 116 species, 16 genera. Old World, mainly Africa, also Madagascar and southern Asia.

Estrildidae. Estrildid finches. Small grass-seed eaters of Old World Tropics. The young have a barred or spotted pattern inside the mouth, and the palate and outer gape have patterns, shapes and colors often unique to the species. Build a covered nest of thatch, or take over abandoned nests of other birds (23 species sometimes or often do this); Gouldian finch Chloebia gouldiae nest in holes. Mainly grassland, a few species live in forests. Three main lineages: Estrildinae waxbills (including Ortygospiza quail-finch and Amadina cut-throat finch in Africa, Amandava are in both Africa and Asia), Erythrurinae parrot finches (Australasia), and Lonchurinae (grassfinches, munias and mannikins in Australasia, secondarily in Africa and Madagascar). 126 species, 31 genera, Old World.

Viduidae. Vidua finches, indigobird, whydah(2). Brood parasites on certain African estrildid finches (Estrilda and Granatina waxbills, Lagonosticta firefinches, Clytospiza, Euschistospiza & Hypargos twinspots, Amandava subflava goldbreast, Ortygospiza quail-finch and Pytilia pytilias). Viduidae and Estrildidae finches are similar in DNA-DNA hybridization pattern, mtDNA nucleotide sequences, and feather tracts; whereas viduas and Euplectes finches (Ploceidae) are similar in seasonal and sexual plumage dimorphism. Vidua nestlings share the mouth patterns and colors in most species of their estrildid host species in a unique mimetic pattern, and in most species the adult males mimic songs of their host species. One species, cuckoo-finch or cuckoo-weaver Anomalospiza imberbis, a brood parasite on cisticola and prinia grass-warblers, is related to Vidua on the basis of DNA sequence data and morphology (skull, feather tracts). 20 species, 2 genera. Africa.

2. Finches and New World nine-primaried oscines

Fringillidae. Finches. Thick-billed nine-primaried oscines, typically with a short pointed bill, conical in cross-section. Two groups: Fringillinae (chaffinches and brambling, 3 species, 1 genus, Palearctic; and Carduelinae. Cardueline finches, including canaries and the diverse Hawaiian honeycreepers "Drepanididae"with bill variable in shape, sickle-shaped, small and slender, or thick and swollen. Hawaiian honeycreepers include 30 species (8 extinct, also others known from Recent cave deposits only), 8 genera. Hawaiian honeycreepers are a subset of finches in DNA-DNA hybridization. Carduelines typically have red and yellow plumage pigmentation, and uniformly are characterized by a thick, double-walled interorbital septum (lacking in Fringilla), and behaviorally in nesting, including leaving feces in the nest. Fringillidae in the broad sense includes 152 species (1 extinct in addition to the honeycreepers), 26 genera, mainly Nearctic, Palearctic, and African.

Emberizidae. Old World buntings and New World sparrows Emberizinae, and the cardinals and New World buntings Cardinalinae. Nine-primaried oscines with bills cone-shaped ("seed-splitters") or thick-billed ("seed-crackers"). Plumage streaked in typical emberizines, plumage often uniform in cardinalines. DNA-DNA hybridization data suggests that Cardinalinae comprises two groups, the cardinal grosbeaks are the sister group of the icterids, and the small tropical finches or "tanager-finches" such as saffron finch Sicalis, seed-eaters Sporophila, and grassquit Volatinia are tanagers but here are included in Emberizidae. Darwin's finches Geospiza in recent genetic sequence sequence data appear to be sister group to Tiaris, also a "tanager-finch". In the traditional scheme, Emberizidae includes 327 species, 70 genera. New World, also Palearctic, southern Asia, Africa.

Peucedramidae. Olive warbler Peucedramus. Basal to the other New World nine-primaried oscines, plumage olive-gray with an orange or yellow head, dark face stripe and white wing bars. 1 genus, 1 species. North America.

Thraupidae. Tanagers, honeycreepers, flowerpiercers, bananaquits, conebills, swallow-tanager, plush-capped finch. Nine-primaried oscines, bill typically thick and somewhat rounded in side and dorsal view, plumage brightly colored, fruit-eating arboreal birds, but not all are typical. Family and group limits are not well known (see Emberizidae and Parulidae), here tanagers include the New World honey-creepers "Coerebidae" on the basis of DNA-DNA hybridization data, and by the pinnate-palmate jaw muscle fibers not indicating family relationships (both occur in New World orioles). Euphonia "finch-tanagers" may not be tanagers and may be related to Tiaris et al. 231 species, 55 genera. New World, mainly tropical.

Parulidae. New World warblers, wood-warblers. Nine-primaried oscines, typically small and slender-billed. New World warblers include 124 species, 29 genera. New World.

Icteridae. Troupials, meadowlarks, American blackbirds, cowbirds, American orioles Icterus, and oropendolas. Nine-primaried oscines typically with long slender bills, culmen straight not curved, five species (cowbirds) are brood parasites. Plumage is mainly black, brown, or yellow. 97 species, 26 genera. New World.

Conservation and extinction: who was that extinct bird?

About 90% of the known extinctions of bird species in the past two centuries have been on oceanic islands and due to human predation or the introduction of predators by humans. This list of extinct birds updates the lists in Dictionary and in Sibley & Monroe 1990 (including ground finch Neospiza concolor rediscovered in São Tomé in ca 1991, and forest owlet Heteroglaux blewitti rediscovered in India in 1997). Extinct: Aepyornithidae (9 species), Dinornithidae (11), Hydrobatidae (1), Podicipedidae (2), Phalacrocoracidae (1), Anatidae (3), Phasianidae (1), Accipitridae (1), Rallidae (9 &endash; or perhaps 100 times that number, based on subfossils on islands of the Pacific), Haematopodidae (1), Scolopacidae (1), Alcidae (1), Columbidae (2), Raphidae (3), Psittacidae (14), Cuculidae (1), Caprimulgidae (1), Acanthisittidae (1), Ptilonorhynchidae (1), Meliphagidae (3), Callaeidae (1), Turdidae (1), Zosteropidae (1), Sturnidae (1), Fringillidae (1), Drepanididae (8). Total this list, 82 species, includes extinct families Aepyornithodae, Dinornithidae, and Raphidae, but excludes recently discovered birds known only from cave deposits in Hawaii and Amsterdam Island where extinction was earlier. Under a criterion of not having been seen for at least 50 years, the missing southeast Asian white-eyed river martin Pseudochelidon sirintarae, "extinct" in Robson 2000, is not extinct (has not been seen lately, but was seen as recently as 20 years ago). South American Kalinowski's tinamou Nothoprocta kalinowskii was not reported for 100 years, but a sighting in 2000 and the later reidentification of a museum specimen taken in 1970 (de Vasconcelos 2002) indicates the species's survival at least to a later date.

A slightly different list of 90 species is in "extinct birds," in A Dictionary of Birds 1985. This includes subfossils and some "possibly extant." In addition, see list of endangered and threatened bird species in Collar et al. 1994, and last two chapters in:

Bird Population Studies, ed. by C. M. Perrins, J.-D. Lebreton & G. J. M. Hirons. 1991. Oxford: Oxford University Press.

Collar, N.J., M.J. Crosby & A.J. Stattersfield. 1994. Birds to Watch 2, the World List of Threatened Birds. BirdLife Conservation Series no. 4.

Furness, R. W. & J. J. D. Greenwood. 1993. Birds as Monitors of Environmental Change. London: Chapman & Hall. QL 698.95 B5851

Heywood, V. H., Mace, G. M., May, R. M. & Stuart, S. N. 1994. Uncertainties in extinction rates. Nature 368:105. Order of magnitude differences: historically ca 1 species of bird + mammal have gone extinct / year this century. This gives an average 'species lifetime' of ca 104 years. This is 2 to 3 orders of magnitude shorter than the average species lifetime of 106 to 107 years as seen over the sweep of the fossil record (Rapp, C. M., Paleobiology 4:1-5, 1978), but it is 2 orders of magnitude longer than the impending extinction times that conservationists predict, (1) from observed rates of habitat loss plus island-based species-area relations, (2) extrapolating rates at which species "climb the ladder" of IUCN categories of threat from "vulnerable" to"endangered" to "extinct," and (3) using assessments of species-by-species extinction probability distributions as functions of time (IUCN), estimated that half the species in each of 4 families or orders of birds will go extinct in 300-400 years. Empirical bases of these assumptions are weak. The argument suggests that destroying 90% of a habitat will eventually lead to loss of 50% of the species in it, but time to a loss is not specified, just that once a species' demographic and genetic base has been sufficiently eroded it is "committed" to extinction.

Skipnes, K. 1999. Ornamental use of feathers and the development of bird protection c. 1870-1930. Stavanger Museum, Zoologiske Meddel. 16. &endash; Final extinction of huia perhaps due to use of feathers in human male ornamentation; more widespread population losses of birds were due to human female ornamentation.

von Euler, F. 2001. Selective extinction and rapid loss of evolutionary history in the bird fauna. Proc. Royal Soc. London B 268:127-130. using Sibley & Ahlquist tree, estimates unequal probabilities of extinction among clades.

Bird wings, fifth secondary

Eutaxic condition: 5th secondary present

Diastataxic condition: 5th secondary absent but its greater covert present

cf. H. Steiner, 1918, Das Problem der Diastataxie des Vogelflugels. Jenaische Zeitschrift für Naturwissenschaft, Band 55, discovered the embryological origin by which diastataxy develops. During ontogeny the first 4 secondary feather germs migrate forward and develop as coverts. The equivalent under wing coverts move up and develop as "secondaries." At the location of the 5th secondary the true secondary feather germ moves forward but the under wing covert fails to move up -- thus the gap at the 5th secondary position results. The resulting secondaries, from S6 on, develop in their original positions.

In general the diastataxic condition is found in long-winged birds, namely: Gaviiformes, Podicipediformes, Procellariiformes, Pelecaniformes, Ciconiiformes, Anseriformes, Falconiformes, Charadriiformes (except American woodcock), Psittaciformes, Strigiformes, Caprimulgiformes, some Gruiformes, rollers.

Eutaxic groups are ratites, tinamous, Galliformes (except some megapodes), mesites, some Gruiformes, cuckoos, tauracos, Coraciiformes (except rollers), trogons, Piciformes, Passeriformes.

In the following families some species are eutaxic, others diastataxic: megapodes, doves, rails, buttonquail, sandpipers (one eutaxic), kingfishers, swifts, hummingbirds.


In 1867 (Proc. Zool. Soc. London), T.H. Huxley proposed a classification based upon the relationships of the bones of the palate. Five palate types were proposed:

1. Dromaeognathous. a) Vomer large, broad posteriorly, articulates anteriorally with the premaxilla and maxillopalatines and posteriorly with the pterygoids (except in Struthio). b) Pterygoid is interposed between palatine and parasphenoid) ("basisphenoid") rostrum. c) Palatine articulates with pterygoid along a long suture. d) Basipterygoid ("basitemporal") process is large, near posterior end of pterygoid. e) Pterygoid-quadrate articulation is complex and includes part of the orbital process of the quadrate. This type of palate is found, with variations, in ratites and tinamous. Also called "palaeognathous" although this term assumes an evolutionarily primitive condition and this has not been established.

2. Desmognathous. Vomer small or absent, maxillopalatines in contact in midline, forming a bony bridge under the naso-frontal region. Pterygoids and palatines articulate with parasphenoid rostrum. Greek_desmos = bond, bridge. e.g. Anseriformes, Falconiformes, Pelecaniformes.

3. Schizognathous. Vomer sometimes small, but present, and usually terminating anteriorly in a point. Maxillopalatines variable in size and shape and not meeting in mid-line with each other or with the vomer. Greek schizo = split. e.g., Charadriiiformes, Columbiformes.

4. Aegithognathous. Vomer broad and truncate anteriorly. Maxillopalatines do not join but do touch parasphenoid rostrum. e.g., Passeriformes.

5. Saurognathous. Maxillopalatines small, hardly extend inwards from the maxilla, hence skull is widely schizognathous. Vomers are delicate paired rods. Woodpeckers.


Basipterygoid process

In ratites and tinamous, originates from basisphenoid and articulates with pterygoid. In other birds, when present, originates from basisphenoid rostrum, and does not articulate with pterygoid. In passerine birds, present in embryo but not in adult.

Feet and toes

anisodactyl: #1 back, #2, 3, 4 forward. e.g. Passeriformes.

zygodactyl. #1 and 4 back, #2 and 3 forward. e.g. Cuculiformes. In woodpeckers, 1 sometimes missing, 4 directed laterally in life.

syndactyl. #2-4 united at base, #3-4 united through second digit. e.g. Kingfishers.

heterodactyl. #1 and 2 back, #3 and 4 forward; in life #2 often directed forward.

pamprodactyl. all toes directed forward ("pam" derived from "pan" = all, "pro" = forward, "dactyl" = toes). Mousebirds, some swifts.

Digit formula, numbers of phalanges per toe in order #1, 2, 3, 4: 2-3-4-5. Other patterns occur, as in 2- and 3-toed birds, in Caprimulgus and Pterocles where 2-3-4-4, in some Procellariiformes where 1-3-4-5, in some swifts where adults 2-3-3-3 but with 4 discernible in digits 3 and 4 in ontogeny.


Schizorhinal: posterior edge of the bony nostril cleft to or beyond the premaxillaires; e.g. Columbidae, Laridae, Charadriidae, Gruidae, Alcidae.

Holorhinal: nostrils entire, not deeply cleft; e.g. Struthioniformes, Anseriformes, Falconiformes, Apodiformes, and most others except those under schizorhinal.


Pervious: an incomplete nasal septum, hence the opening extends through from side to side, as in loons, grebes, tropicbirds, herons (except Cochlearius), storks, flamingos, Anseriformes, Cathartidae, Rallidae, and Gruidae.

Impervious: nasal septum present, either cartilaginous or ossified, as in Charadriiformes, Balaeniceps, owls, and nearly all Passeriformes.

Tarsal envelope or podotheca

Pycnaspidean: anterior side covered with large scutes, posterior with small scales.

Exaspidean: anterior and external sides covered with large scutes, internal sides bare or with small scutes.

Endaspidean: anterior and internal sides with large scutes, external bare or with small scutes.

Taxaspidean: large anterior scales, small posterior scales.

Ocreate: anterior scutes, long solid "boot" behind.

Holaspidean: the broad plantar space occupied by a single series of broad, more or less rectangular, scutes.


"Syrinx" is the name of a mythical Greek water nymph who metamorphosed into a reed to escape the amorous attentions of Pan. The transformation was to no avail, since Pan plucked the reed to make his pipe. Like Pan's, the syrinx in birds is the song-producer. Three basic types based on location.

1. Tracheophone or Tracheal = in trachea (most New World suboscine Furnari Passeriformes)

2. Haploophone or Bronchial = in bronchi (cuckoos, nightjars)

3. Tracheobronchial = at junction of trachea and bronchi (oscine Passeriformes).

In the Passeriformes the syringeal structure is utilized in the morphological diagnosis of suborders. The number of pairs of intrinsic muscles (intrinsic = muscle both originates and inserts on syrinx) and their insertion upon the bronchial half-rings are important. The number of intrinsic muscle pairs is diagnostic for certain groups: 2 or 3 pairs in lyrebirds, 4 or 5 pairs in other oscines. Some terms:

Mesomyodian syringeal muscles attach to the middle of the bronchial half-rings.

Anisomyodian = syringeal muscles unequally inserted, either in the middle or on one end of bronchial half-rings, with two subtypes--

1. catacromyodian = intrinsic muscles insert on ventral end of half-rings.

2. acromyodian = intrinsic muscles insert on dorsal end of half-rings.

The above types occur in the passeriform suborders Eurylaimi and Tyranni.

Diacromyodian = intrinsic syringeal muscles attach to both ends of bronchial half-rings. Passeres (oscines, including lyrebirds).

Vertebral shapes

Heterocoelous, ampisthocoelous, opisthocoelous (Charadriiformes, Pelecaniformes, Spheniscidae, Psittacidae): refer to shape of the vertebral centrum.

For terms, see Van Tyne and Berger, Fundamentals of Ornithology; and Baumel, 2nd ed.

Cervical vertebrae

Cervical vertebrae are distinguished from thoracic vertebrae in not articulating with a complete rib. A "complete rib" has both vertebral and sternal segments, and it connects directly or indirectly with the sternum. Vertebrae at the root of the neck that bear moveable ribs which do not raech the sternum have been called "vertebrae cervicodorsales" which are transitional between cervical and thoracic vertebrae.

Thoracic vertebrae

Fused thoracic vertebrae occur in several groups (apparently evolving independently 10 times). Fusion refers to the 4-5 fused thoracic vertebrae anterior to a free vertebra that is anterior to the fused pelvis, though the number varies in this compound bone (notarium). See Storer 1982.

1- all fused: tinamous, grebes, flamingos, Galliformes, hoatzin, Columbiformes, sandgrouse

2- some fused: Pelecaniformes (some cormorants), Ciconiiformes (Threskiornithidae), Falconiformes (Falconidae except Herpetotheres and Micrastur), Gruiformes, Caprimulgiformes (Steatornis)

3- all unfused: ratites, loons, penguins, Procellariiformes, Anseriformes, Charadriiformes (including Pedionomus), Psittaciformes, Cuculiformes, Strigiformes, Apodiformes, Coraciiformes, Piciformes, Passeriformes.

Gruiformes: all fused in [mesites], cranes, limpkin, trumpeters, kagu, sunbittern, [hoatzin]; all unfused in [buttonquail,] rails, finfoots, seriemas, bustards.

c 2003 Univ. Michigan