Yourself answers

1. What are birds?

Birds are the most successful flying animals that have ever existed. They make up the scientific class Aves, distinguished from other animals by one feature: feathers.

2. Are birds’ feathers just for flight?

They are not just for flight – they also provide a warm coat to trap heat in the body. Birds are warm blooded, which means they maintain a constant internal temperature.

3. How do birds eat food?

Since birds have no teeth, they must break up food inside their bodies. They have a special stomach chamber called a gizzard, with powerful muscular walls that squeeze and grind the food.

4. Do birds have a sense of smell or hearing?

Most birds have a poor sense of smell but excellent hearing. What sounds to us like a single note of birdsong might be heard by a bird as 10 separate notes.

5. How do birds care of eggs and chicks?

Usually both parents cooperate to keep the young warm, and to protect and feed them.

6. What provides birds’ “lift” to overcome gravity?

Wings and feathers are the most obvious features – they provide the “lift” to overcome gravity.

7. How much oxygen do birds need for flight?

The flight muscles are huge and powerful, but they need plenty of oxygen, so birds have special lungs to extract as much oxygen as possible from the air.

8. What are feathers?

Feathers are made of fine, lightweight fibres of keratin, the protein that coats bills. Flight feathers have a stiff central shaft, called a quill, with hundreds of side branches called barbs.

9. Where are the bird’s most important feathers?

The bird’s most important feathers are its flight feathers, found on the wings and tail. Most of the lift required for flight is generated by the primary and secondary flight feathers in the outer part of the wing. There are usually 9-12 of these on each wing.

10. How do birds care of their feathers?

Feathers need a lot of care. The tiny barbules that keep them flat can come unzipped. Birds run their bills through the feathers to zip the barbules back together. Many birds also rub oil from a gland in the rump into the feathers to waterproof them. Some also bathe in puddles or dust to keep the feathers in shape.

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