Animals and their groups · Grade 3

There are millions of kinds of animals. Animals with a backbone (vertebrates) are sorted into five groups: fish, amphibians, reptiles, birds and mammals. We can also sort animals by what they eat: carnivores eat meat, herbivores eat plants, and omnivores eat both.

Key facts

• Fish live in water, breathe with gills, have scales and fins, and most lay eggs.
• Amphibians, like frogs and newts, have smooth, moist skin. They start life in water and many live on land as adults. They lay their eggs in water.
• Reptiles, like snakes, lizards, crocodiles and tortoises, have dry, scaly skin. Most lay eggs with leathery shells on land.
• Birds have feathers, wings and a beak, and lay eggs with hard shells. Most birds fly, but some can’t, like penguins and ostriches.
• Mammals have hair or fur and feed their babies on milk. Most give birth to live young. Humans, whales and bats are mammals.
• Carnivores eat other animals, herbivores eat only plants, and omnivores eat both plants and animals.
• Animals without a backbone are invertebrates: insects have 6 legs and spiders have 8.

Worked examples

Other years

• Animals and their groups · Grade R
• Animals and their groups · Grade 1
• Animals and their groups · Grade 2
• Animals and their groups · Grade 4