Birds
Birds are vertebrates with feathers, two wings and a beak with no teeth. They breathe with lungs, keep their bodies warm, and lay eggs with a hard shell, which they sit on to keep warm until the chicks hatch. Most birds fly, but not all: ostriches and penguins can't.
Depth 1 · Foundation
You can tell a bird by its feathers, beak and hard-shelled eggs, even a bird that can't fly.
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Foundation
You can tell a bird by its feathers, beak and hard-shelled eggs, even a bird that can't fly.
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