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The below mentioned article provides notes on Columba Livia.
Columba livia is the scientific name of common pigeon (Fig. 143). It belongs to the class Aves which includes all the birds of the world. Most birds can fly in air. This peculiar habit has rendered certain changes in them, which are regarded as their characteristics.
Some of these features are mentioned below, which are well seen in pigeon:
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1. Body streamlined.
2. Forelimbs are modified as wings which help in flying.
3. Heavier parts of the body are centrally placed.
4. Body covered by feathers which help in buoyancy of the; birds.
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5. Bones are hollow and filled up with air.
6. Well-developed air-sacs are associated with respiratory organs.
7. Tail is short and works both as rudder and balancer.
8. Homoiothermal or warm-blooded.
There are innumerable varieties of domesticated pigeon. In all of them the body is divisible into three parts—head, neck and trunk. The head is small and movable due to the neck. Mouth is placed at the anterior most end and is provided with two beaks. Each beak is hard and pointed. The beaks are used for picking food and also for defence.
Slightly above the mouth there is a pair of nasal opening. On each side of the head lies a large, prominent eye. Each eye is provided with three movable eyelids—upper, lower, and nictitating membrane. The auditory openings are present posterior to the eye. The forelimb containing three digits is modified into wing. Each wing is provided with 23 long feathers called remiges.
The hind limbs are capable of supporting the entire weight of the body and are used during perching and sitting. The digits of the hind- limbs are provided with sharp claws, which are used for defence. Number of scales is present on the hind limb.
Tail is short and provided with 12 long feathers called retrices. Near the base of the tail, lies an oil producing gland called preen gland, the secretion of which keeps the feather clean and prevents from becoming wet. On the ventral side of the caudal region lies the anal aperture.