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BS Media
By BS Media Twitter Profile
Published: Saturday, 01 July 2017
Updated: Saturday, 01 July 2017 13:45
Based on characters of  Aves Class is divided into 2 sub-classes.

Sub class: i) Archeornithes and Subclass ii) Neornithes
1. Sub class Archeornithes:
  1. In this subclass extinct birds are included. Those birds were alive in Mesozoic era.
  2. These show a long tail with 13 or more than 13 caudal vertebrae.
  3. Pygostyle is absent.
  4. Meta carpals are free. The free fingers of fore limb will end with claws.
  5. Thecodont teeth are seen.
Archeopteryxfossil thumb10
Eg: Archeopteryx, Archeormis
2. Sub class Neornithes:
  1. This subclass includes both extant and extinct birds.
  2. Tail ends in pygostyle. The rectrices are arranged r a semi circular around pygostyle.
  3. Teeth are absent in many forms.
  4. Sternum is well developed. It shows a keel to which flight muscles are attached.

This subclass is divided into 4 super orders.
  1. Odontognathae
  2. Palaeognathe
  3. Impennae
  4. Neognathae
1. Super Order: Palaeognathae:
  1. These are flightless birds.
  2. They are more in numbers.
  3. Wings are reduced or absent.
  4. Teeth are absent.
  5. Caudal vertebrae are free.

This super order is divisible into 7 orders.

1. Order: Struthioni:
Ex: Struthio camelus (Two toed African Ostrich (or) Ostrich)
  1. Large flight-less bird.
  2. Feathers are less.
  3. They show two toed hind limbs.
  4. Sternum is without keel.
  5. Neck is very long and flexible.
  6. Pygostyle is absent.
  7. These birds are good runners.
StruthioAfricanOstrich thumb10

2. Order: Rheiforms:
Rhea americana. (three toed (or) American ostrich).
  1. This includes flightless, terrestrial bird.
  2. They are good runners.
  3. Wings are better developed.
  4. The body shows more feathers.
  5. The hind limb bear three toes.
  6. Sternum is without keel.
Rheaamericanaostrich thumb15

3. Order: Casuariformes:
Ex: Casuarius (Casso waries), Dromaeus (Emu)
  1. These are flightless terrestrial birds.
  2. Head shows few feathers.
  3. Neck and body show more feathers.
  4. Wings are Rudimentus.
  5. The hind limb shows three toes.
Casuariusemu thumb11
4. Order: Aepyomithiformes:

Ex: Aepyornis.
  1. These are extinct elephant birds.
  2. Wings are vestigeal.
  3. Legs are powerful.
  4. Hind limbs show 4 toes.
  5. Sternum is broad.
  6. Keel is absent.
  7. Eggs are very big.
5. Order: Dinomithiformes:
Ex: Dinornis (Extinct Moas)
  1. These are gaint flightless extinct birds.
  2. Wings are absent.
  3. Eggs are massive.
  4. Sternum is reduced without keel.
  5. Pectoral girdle is absent.
6. Order: Apternygiformes:
Ex: Apteryx (Kiwi), Newzealand bird
  1. These are flightless, terrestrial birds.
  2. Wings are rudimentary.
  3. Eyes are small.
  4. Neck and legs ve small.
  5. Hind limbs bear 4 toes.
  6. These are Nocturnal. They feed on insects.
  7. Eggs are largest relatively.
  8. These are present only in Newzeland and Australia.
7. Order: Tinamiformes:

Ex: Tinamus.
  1. These are small, terrestrial with little power of flight.
  2. Wings are short and round.
  3. Pygostyle is reduced.
  4. Eggs are big.
  5. They eat plant products.
2. Super Order: Impennae:

This super order includes flightless aquatic birds.
  1. Their foreKmbs are modified into paddles.
This super order includes only one order.
1. Order: Sphenisci formes (SPHENISCI FORMES):
Ex: Aptenodyts (Penguin)
  1. These are flightless aquatic birds.
  2. Feathers are small scale like. They cover the. entire body.
  3. Forelimbs are modified into paddles. They are useful for swimming
  4. Limbs are 4 toes.
  5. Below the skin thick layer of fat will be present.
AptenodytsPenguin thumb17

3. Super Order: Neognathae:
  1. This sub order includes modern flying birds.
  2. Teeth are absent.
  3. Wings are well developed.
  4. Sternum shows keel.
  5. Flight muscles are well devebped.
  6. Pygostyle is present.
This super order is divisible into the following orders.
1. Order: Gaviformea

Ex: Gavia immer (Common loon)
  1. These birds show powerful fight
  2. Toes are webbed.
2. Order: Podlcipit formes:
Ex: Podiceps.
  1. These are fresh water birds.
  2. Feet are lobed.

3. Order: Procellariiformes:

Ex: Puffinus (Petrels, Diomedia ) ( Wandering albatross)
  1. Skull shows large nasal gland.
  2. Feathers are compact.
  3. Wings are long and narrow.
4. Order: Pelecaniformee:

Ex: Pelecanus (Pelecan)
  1. Aquatic fish eating birds.
  2. Four toes are webbed.
5. Order: Clconiformee:

Ex: Ardea (great blue heron)
  1. Neck is long and Legs are long
  2. Web is absent.
6. Order: Ariseriformea:
Ex: Anser domesticus (Duck), Cygnus (swan)
  1. Beak is broad.
  2. Tongue is fleshy.
  3. Legs are short.
  4. Feet are webbed.
7. Order: Faiconl forme:
Ex: Mihms migrans (Kite). Pseudogyps (Vulture)
  1. Beak is short and curved.
  2. Feet show curved daws.
  3. They are strong fleers.
kite thumb19
8. Order: Galliforroea:
Ex: GaOus (Jungle Fowl), Pavo cristatus (Peacock)
  1. Beak is short.
  2. Terrestrial birds.
  3. They will fly.
9. Order: Gruiformes:
Ex: Grus (crane)
  1. They are small or medium large-size birds.
  2. They may be weak or strong fliers.
  3. Legs are long.
10. Order: Diatrymiformee:
  1. These are extinct birds.

11. Order: Chardriiforrae:
Ex: Larus (Gull)
  1. Shore dwelling aquatic birds.
  2. Toes are webbed.
12. Order: Columbiformes:

Ex: 1. Columba livia (Pigeon), 2. Sterptopelia (Dove)
  1. Skin thick and soft.
  2. Beak is usually short and slender.
  3. Crop produces pigeon milk to feed the young ones.
ColumbaliviaPigeon thumb11
13. Order: Cuculiformee:

Ex: 1. Cuculus (cuckoo), 2. Eudynamis (Koel)
  1. Many Cuckoos are parasites.
  2. The females lay their eggs in the nests of other birds.
  3. The toes are four in number.
  4. Tail is long.
14. Order: Paitiaciforme:

Ex: Psittacula eupatra (Parra keet)
  1. Feathers are green, blue, yellow.
  2. Beak is short and curved.
  3. Frugivorus forms.
15. Order: Strlgiformes:

Ex: Bubo bubo (green horned owl)
  1. Head is large and narrow.
  2. Retina contains many rods. Hence it can see in the night time.
  3. They are nocturnal predators.
16. Order: Caprimulgiformee:
Ex: Caprinulgus (Night jar)
  1. Legs are weak.
  2. Beak is small.

17. Order: Apodiformes:
Ex: Swift (Humming bird)
  1. These are small birds.
  2. They are powerful fliers.
18. Order: Coliifbrmee:
Ex: Cobus (Mouse bird)
  1. Small birds.
  2. Tail is long.
19. Order: Coraci formes:
Ex : Akedo king fisher and hornbill
  1. Beak is strong. It is useful to catch fishes.
  2. Third and Fourth toes are fused at the base.
20. Order: Piciforme:

Ex: Brachypternus (Wood pecker), Dinopium (Wood pecker)
  1. Tail feathers are pointed.
  2. Beak is stout.
21. Order: Passed formes:
Ex: 1 Passer domesticus (Sparrow), Corvus (Crow), Acridotherus (Myna)
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