Many animals lay eggs, including:

• Birds: Birds are warm-blooded and lay eggs. Most have feathers and can fly.

• Fish: Fish are cold-blooded vertebrates. Most lay eggs, have scales, and breathe using oxygen in the water. They swim in the sea (marine fish) or in lakes and rivers (freshwater fish) .

• Amphibians: Amphibians are cold-blooded vertebrates and can live on land and in water. Amphibians lay eggs.

• Reptiles: Reptiles use the heat of the sun to keep their blood warm. Most reptiles are oviparous - they produce eggs.

• Insects: Insects are the biggest group of living things, apart from bacteria. Most lay eggs.

• Mammals: Only two mammals lay eggs: the platypus and the echidna. All other mammals give birth to live babies.

Egg-laying is a reproductive strategy used by many species of animals, from reptiles and birds to some species of fish and invertebrates. The basic idea behind egg-laying is that the eggs are laid outside of the mother’s body, providing a safe and protected environment for the developing offspring.