Describe the aerial adaptations in birds.

Various aerial adaptations found in birds are:

1. Body shape — The body of birds is streamlined. Necks stretched forward with the head pointed in front and a narrowed tail at the end provide them a sleek shape. The body surface is smooth to minimize resistance against air.
2. Wings — The forelimbs are modified into wings. The whole length of the forelimbs carries long light feathers.
3. Steering and brakes — The feathers on the tail help to slow down the speed and also help in steering (changing direction).
4. Wing muscles — These are the strong, active and enlarged breast muscles which support and help in the movement of wings.
5. Cutting down the body weight — Except for the most necessary bulky heavy wing muscles, the rest of the bird's body tends to be light to facilitate flight.
   1. Bones have air cavities.
   2. Much less water is required in the body. The birds excrete solid urine (formed of uric acid instead of urea which otherwise requires much water to be excreted out).