What was the first bird? Which is the most advanced? What are the relationships among the thousands of species in existence today? Taxonomy, the science of classifying species of living things, helps answer these questions by grouping birds with similar traits.
The 18th-century taxonomist Carolus Linnaeus devised the classification system used today, and he established the class Aves, into which all birds are placed. Over the centuries, ornithologists have added innumerable species and modified Linnaeus' work. Today they recognize 27 living orders and one extinct order of birds divided into about 200 families containing more than 8,800 species. Closely related species within a family group share a common genus name -such as Laurus in the case of Laurus argentatus, the herring gull, and Laurus delawarensis, the ring-billed gull.
The largest order of birds, by far, is the order Passeriformes, the "perching birds," with some 60 families. Ornithologists consider the perching birds to be the most recently evolved and specialized, or advanced, species. Among the most ancient, or primitive, are the six families of flightless birds, such as ostriches and penguins. The following classification begins with the most ancient order and progresses to the diverse and successful Passeriformes.
Phylum: CHORDATA
Subphylum: VERTEBRATA: Animals with backbones
Class: AVES; Birds
1. Order ARCHAEOPTERYGIFORMES: The extinct "dawn birds," with one known family and one known species. Identified from pigeon-sized fossil about 140 million years old. In essence, a feathered, flying reptile. Example: Archaeopteryx.
2. Order STRUTHIONIFORMES: Ostriches, with one family and one species. The world's largest living bird, flightless, found in arid regions of Africa. Example: ostrich.
3. Order RHEIFORMES: Rheas, with one family and two species. Large, flightless birds, found in scrublands of South America. Example: common rhea.
4. Order CASUARIIFORMES: Cassowaries and emus, with two families and four species (one emu and three cassowaries). Large, flightless birds, found in wooded and grassy areas of Australia, New Guinea, and Indonesia. Example: double-wattled cassowary.
5. Order APTERYGIFORMES: Kiwis, with one family and three species. Small- to medium-sized, flightless birds, found in brushy habitats of New Zealand. Example: brown kiwi.
6. Order TINAMIFORMES: Tinamous, with one family and 46 species. Chickenlike ground birds, found in forests, bushlands, andgrasslands of Central and South America. Examples: great tinamou and crested tinamou.
7. Order SPHENISCIFORMES: Penguins, with one family and 18 species. Flightless marine birds with paddlelike wings, found in cold, southern oceans. Example: emperor penguin.
8. Order PODICIPEDIFORMES: Grebes, with one family and 19 species. Fast-swimming freshwater birds of Eurasia, Africa, Indonesia, and Australia. Example: little grebe.
9. Order GAVIIFORMES: Loons, with one family and five species. Freshwater and marine diving birds of the high Northern Hemisphere. Example: red-throated loon.
10. Order PROCELLARIIFORMES: Albatrosses, shearwaters, and petrels, with four families and 80 to 100 species. Birds of the open sea, with unique external, tubular nostrils. Found in all oceans. Example: wandering albatross.
11. Order PELECANIFORMES: Pelicans, gannets, boobies, tropic birds, cormorants, darters, and frigate birds, with six families and 60 species. Medium to large web-footed waterbirds, most of which eat fish. Found worldwide in freshwater and oceans. Examples: brown booby, rough-billed pelican, and anhinga.
12. Order CICONIIFORMES: Herons, storks, ibises, and flamingos, with six families and about 125 species. Storklike wading birds with long legs and unwebbed feet, many of which have long necks and pointed or down-curved beaks. Found worldwide near water. Examples: cattle egret and Japanese crested ibis.
13. Order ANSERIFORMES: Screamers, swans, geese, and ducks, with two families and about 143 species. Web-footed waterbirds. (Screamers have partially webbed feet.) Found worldwide. Example: Canada goose.
14. Order FALCONIFORMES: Birds of prey, with five families and about 300 species. Daytime hunters such as hawks, New World vultures, ospreys, falcons, and secretary birds. Found worldwide. Examples: bald eagle, red-tailed hawk, California condor, turkey vulture, and great horned owl.
15. Order GALLIFORMES: Wildfowl (also called upland game birds), with seven families and about 250 species. Includes the curassows, hoatzins, and pheasants. Adapted for living on the ground and eating seeds, with the exception of curassows and hoatzins. Found worldwide. Examples: peafowl, quail, and turkey.
16. Order GRUIFORMES: Cranes, rails, bustards, and their relatives, with 12 families and some 200 species. Diverse and ancient group of wading and ground birds, some quite rare. Found worldwide. Example: whooping crane.
17. Order CHARADRIIFORMES: Plovers, sandpipers, gulls, terns, auks, and their kin, with 15 families and some 300 species. Diverse group of water- and shorebirds, grouped together for their common skeletal traits. Found worldwide. Example: herring gull.
18. Order COLUMBIFORMES: Sandgrouse and pigeons, includes two living families with 310 species, and the extinct dodo family with three species. Typically stout, strong birds of plains and open woods, found worldwide. Example: mourning dove.
19. Order PSITTACIFORMES: Parrots, lories, and cockatoos, with three families and about 310 species. Typically brightly colored, noisy birds, with hooked beaks and zygodactyl feet (two toes pointing forward, two backward). Found in forests of Southern Hemisphere and tropics. Examples: cockatiel, lovebird, macaw.
20. Order CUCULIFORMES: Cuckoos and turacos, with two families and 146 species. Typically slender, strong-billed insect eaters with long tails and unusual arrangement of toes. Found in woodland and scrub. Examples: cuckoo and roadrunner.
21. Order STRIGIFORMES: Owls, with two families and 146 species. Nocturnal predators with large eyes, taloned feet, and powerful wings. Found worldwide. Example: barn owl.
22. Order CAPRIMULGIFORMES: Goatsuckers, frogmouths, potoos, nightjars, and their kin, with five families and 94 species. Typically nocturnal insect eaters, with mottled brown plumage. Most found in tropics. Example: whippoorwill.
23. Order APODIFORMES: Swifts and hummingbirds, with three families and about 390 species. Fast-flying, acrobatic birds with small feet. Hummingbirds include the smallest of birds, many of them brilliantly colored. Examples: palm swift and ruby-throated hummingbird.
24. Order TROGONIFORMES: Trogons, with one family and 36 species. Brilliantly colorful birds with short, stout beaks. Typically eat fruits. Nest in tree cavities. Found in Africa, India, Southeast Asia, and the Americas. Example: collared trogon.
25. Order COLIIFORMES: Mouse birds, with one family and six species. Small, crested birds with short, strong bills, soft plumage loosely attached to the skin, and long tail feathers, found on African savanna. Example: speckled mouse bird.
26. Order CORACIIFORMES: Kingfishers, todies, motmots, bee-eaters, rollers, hoopoes, and hornbills, with 10 families and about 194 species. Typically colorful birds with large, strong beaks. Third and fourth toe jointed at the base. Found in forests and along shores worldwide. Examples: Eurasian kingfisher and red-billed hornbill.
27. Order PICIFORMES: Jacamars, puff-birds, honeyguides, woodpeckers, toucans, and barbets, with six families and about 390 species. Strong-billed birds with zygodactyl feet. Found in woodlands worldwide. Example: toco toucan.
28. Order PASSERIFORMES: Perching birds, with two suborders, 60 families, and about 5,000 species. Typically small birds, with unwebbed feet adapted for perching on twigs. All have 9 or 10 primary flight feathers and about 12 tail feathers. Young born naked and helpless. All sing, although vocal ability varies. Found on dry land in all habitats. This large order is generally subdivided into one large and three small suborders. The three small orders are grouped together as the suboscine, or primitive, perching birds. Their vocal organs and songs are simpler than that of the fourth and largest suborder -the oscines, or songbirds.

The 18th-century taxonomist Carolus Linnaeus devised the classification system used today, and he established the class Aves, into which all birds are placed. Over the centuries, ornithologists have added innumerable species and modified Linnaeus' work. Today they recognize 27 living orders and one extinct order of birds divided into about 200 families containing more than 8,800 species. Closely related species within a family group share a common genus name -such as Laurus in the case of Laurus argentatus, the herring gull, and Laurus delawarensis, the ring-billed gull.
The largest order of birds, by far, is the order Passeriformes, the "perching birds," with some 60 families. Ornithologists consider the perching birds to be the most recently evolved and specialized, or advanced, species. Among the most ancient, or primitive, are the six families of flightless birds, such as ostriches and penguins. The following classification begins with the most ancient order and progresses to the diverse and successful Passeriformes.
Phylum: CHORDATA
Subphylum: VERTEBRATA: Animals with backbones
Class: AVES; Birds
1. Order ARCHAEOPTERYGIFORMES: The extinct "dawn birds," with one known family and one known species. Identified from pigeon-sized fossil about 140 million years old. In essence, a feathered, flying reptile. Example: Archaeopteryx.
2. Order STRUTHIONIFORMES: Ostriches, with one family and one species. The world's largest living bird, flightless, found in arid regions of Africa. Example: ostrich.
3. Order RHEIFORMES: Rheas, with one family and two species. Large, flightless birds, found in scrublands of South America. Example: common rhea.
4. Order CASUARIIFORMES: Cassowaries and emus, with two families and four species (one emu and three cassowaries). Large, flightless birds, found in wooded and grassy areas of Australia, New Guinea, and Indonesia. Example: double-wattled cassowary.
5. Order APTERYGIFORMES: Kiwis, with one family and three species. Small- to medium-sized, flightless birds, found in brushy habitats of New Zealand. Example: brown kiwi.
6. Order TINAMIFORMES: Tinamous, with one family and 46 species. Chickenlike ground birds, found in forests, bushlands, andgrasslands of Central and South America. Examples: great tinamou and crested tinamou.
7. Order SPHENISCIFORMES: Penguins, with one family and 18 species. Flightless marine birds with paddlelike wings, found in cold, southern oceans. Example: emperor penguin.
8. Order PODICIPEDIFORMES: Grebes, with one family and 19 species. Fast-swimming freshwater birds of Eurasia, Africa, Indonesia, and Australia. Example: little grebe.
9. Order GAVIIFORMES: Loons, with one family and five species. Freshwater and marine diving birds of the high Northern Hemisphere. Example: red-throated loon.
10. Order PROCELLARIIFORMES: Albatrosses, shearwaters, and petrels, with four families and 80 to 100 species. Birds of the open sea, with unique external, tubular nostrils. Found in all oceans. Example: wandering albatross.
11. Order PELECANIFORMES: Pelicans, gannets, boobies, tropic birds, cormorants, darters, and frigate birds, with six families and 60 species. Medium to large web-footed waterbirds, most of which eat fish. Found worldwide in freshwater and oceans. Examples: brown booby, rough-billed pelican, and anhinga.
12. Order CICONIIFORMES: Herons, storks, ibises, and flamingos, with six families and about 125 species. Storklike wading birds with long legs and unwebbed feet, many of which have long necks and pointed or down-curved beaks. Found worldwide near water. Examples: cattle egret and Japanese crested ibis.
13. Order ANSERIFORMES: Screamers, swans, geese, and ducks, with two families and about 143 species. Web-footed waterbirds. (Screamers have partially webbed feet.) Found worldwide. Example: Canada goose.
14. Order FALCONIFORMES: Birds of prey, with five families and about 300 species. Daytime hunters such as hawks, New World vultures, ospreys, falcons, and secretary birds. Found worldwide. Examples: bald eagle, red-tailed hawk, California condor, turkey vulture, and great horned owl.
15. Order GALLIFORMES: Wildfowl (also called upland game birds), with seven families and about 250 species. Includes the curassows, hoatzins, and pheasants. Adapted for living on the ground and eating seeds, with the exception of curassows and hoatzins. Found worldwide. Examples: peafowl, quail, and turkey.
16. Order GRUIFORMES: Cranes, rails, bustards, and their relatives, with 12 families and some 200 species. Diverse and ancient group of wading and ground birds, some quite rare. Found worldwide. Example: whooping crane.
17. Order CHARADRIIFORMES: Plovers, sandpipers, gulls, terns, auks, and their kin, with 15 families and some 300 species. Diverse group of water- and shorebirds, grouped together for their common skeletal traits. Found worldwide. Example: herring gull.
18. Order COLUMBIFORMES: Sandgrouse and pigeons, includes two living families with 310 species, and the extinct dodo family with three species. Typically stout, strong birds of plains and open woods, found worldwide. Example: mourning dove.
19. Order PSITTACIFORMES: Parrots, lories, and cockatoos, with three families and about 310 species. Typically brightly colored, noisy birds, with hooked beaks and zygodactyl feet (two toes pointing forward, two backward). Found in forests of Southern Hemisphere and tropics. Examples: cockatiel, lovebird, macaw.
20. Order CUCULIFORMES: Cuckoos and turacos, with two families and 146 species. Typically slender, strong-billed insect eaters with long tails and unusual arrangement of toes. Found in woodland and scrub. Examples: cuckoo and roadrunner.
21. Order STRIGIFORMES: Owls, with two families and 146 species. Nocturnal predators with large eyes, taloned feet, and powerful wings. Found worldwide. Example: barn owl.
22. Order CAPRIMULGIFORMES: Goatsuckers, frogmouths, potoos, nightjars, and their kin, with five families and 94 species. Typically nocturnal insect eaters, with mottled brown plumage. Most found in tropics. Example: whippoorwill.
23. Order APODIFORMES: Swifts and hummingbirds, with three families and about 390 species. Fast-flying, acrobatic birds with small feet. Hummingbirds include the smallest of birds, many of them brilliantly colored. Examples: palm swift and ruby-throated hummingbird.
24. Order TROGONIFORMES: Trogons, with one family and 36 species. Brilliantly colorful birds with short, stout beaks. Typically eat fruits. Nest in tree cavities. Found in Africa, India, Southeast Asia, and the Americas. Example: collared trogon.
25. Order COLIIFORMES: Mouse birds, with one family and six species. Small, crested birds with short, strong bills, soft plumage loosely attached to the skin, and long tail feathers, found on African savanna. Example: speckled mouse bird.
26. Order CORACIIFORMES: Kingfishers, todies, motmots, bee-eaters, rollers, hoopoes, and hornbills, with 10 families and about 194 species. Typically colorful birds with large, strong beaks. Third and fourth toe jointed at the base. Found in forests and along shores worldwide. Examples: Eurasian kingfisher and red-billed hornbill.
27. Order PICIFORMES: Jacamars, puff-birds, honeyguides, woodpeckers, toucans, and barbets, with six families and about 390 species. Strong-billed birds with zygodactyl feet. Found in woodlands worldwide. Example: toco toucan.
28. Order PASSERIFORMES: Perching birds, with two suborders, 60 families, and about 5,000 species. Typically small birds, with unwebbed feet adapted for perching on twigs. All have 9 or 10 primary flight feathers and about 12 tail feathers. Young born naked and helpless. All sing, although vocal ability varies. Found on dry land in all habitats. This large order is generally subdivided into one large and three small suborders. The three small orders are grouped together as the suboscine, or primitive, perching birds. Their vocal organs and songs are simpler than that of the fourth and largest suborder -the oscines, or songbirds.
0 comments:
Post a Comment