A robin, an owl, a duck, a penguin. Some fly high and some cannot fly at all. They are all birds. What makes a bird a bird?
Key idea
Birds have feathers, a beak and two legs, and they hatch from eggs with hard shells. Only birds have feathers.
Why it works
Flying is not the test. Bats, bees and butterflies fly, and they are not birds. Penguins and ostriches cannot fly, but they are covered with feathers, so they are birds. Feathers are the clue that never fails.
Worked example: Let's think it through
A penguin cannot fly. Is it a bird?
- Does a penguin have feathers? Yes, thick waterproof ones.
- Does it have a beak and two legs? Yes.
- Only birds have feathers.
Answer: Yes. A penguin is a bird that swims instead of flying.
Common mistake
Many children think anything that flies is a bird, and that penguins and ostriches are not birds. Look for feathers. Bats and bees fly but have no feathers.
For the grown-up. If you see a feather on a walk, crouch down and look at it closely where it lies. Feathers come only from birds, so a feather means a bird was there.