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Life

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Life

Amphibians

Amphibians are a small group of cold-blooded, vertebrate animals. They include two main groups: the salamanders and newts, and the frogs and toads. The word...

Animals

The process of evolution ensures that only living things that are suited, or adapted, to their environment will survive. An animal or plant that is poorly adapted to its...

LET'S EXPLORE The animal kingdom

Animals are living things that can move about and must eat food to survive. This food may be plants, other animals, or both. Some animals are bigger than houses, while others are...

Birds

Birds are warm-blooded, vertebrate animals with four limbs, the front two of which are adapted into wings. They are the only animals that have feathers. Birds have light, hollow...

Domestic animals

A domestic animal is an animal, for example, a horse, goat, dog or cat, that has been tamed and kept by humans as a work animal, a source of food source, or as pet. Many domestic...

Ecosystems

Animals, plants and other living things, together known as organisms, must survive together in the natural world. They depend on and relate to each other, such as by being plants...

Fish

Fish are vertebrates (animals with backbones) that live in water all of the time. They have hairless, streamlined bodies with fins and a tail. Many have a protective layer of...

Human body

The human body is an amazing natural machine. If you give it food, water, air and warmth, it can walk, talk, think and produce more of its own kind. Flesh and bones, blood and...

LET'S EXPLORE The human body

Humans are members of the animal kingdom. Together with monkeys and apes, we belong to the group of mammals called primates. Like other mammals, we must breathe air and take in...

Insects

Insects belong to a group of invertebrates (animals without backbones) called arthropods. Instead of having an internal skeleton, arthropods have a hard outer skeleton. This is...

Land invertebrates

In every house, garden, field or forest on Earth, there is a world of activity that we seldom notice. On the ground, in the soil, in the air and in the water live many small...

LET'S EXPLORE Mini-beasts

Besides mammals, birds, reptiles and amphibians, there are other kinds of animals that live on land. They are mostly small. Some live in the soil, while others can fly. Still...

Life

Living things are called organisms. We know if something is a living organism, rather than non-living, from several features. First, an organism grows and develops at some stage...

Mammals

Mammals are warm-blooded vertebrates: animals with backbones. Their key characteristic, one possessed by no other kind of animal, is their ability to nurture their young with...

Marine invertebrates

Invertebrates are animals that do not have backbones. Many are only found in the sea. Marine invertebrates are a extremely large and diverse group that includes corals, sea...

Micro-organisms

The commonest living things are bacteria. They are too small to see without a microscope. Bacteria are all around us in their billions. They float in air and live on icy...

Ocean life

Although the oceans make up by far the largest biome on Earth, only about 20% of Earth’s species live in the oceans, of which about 90% are bottom-living, shallow-water...

Plants

The second largest kingdom of living things after animals is the plants. The key feature of a plant which sets it apart from other living things is that it obtains energy by the...

Reptiles

Reptiles are cold-blooded animals with scaly skins. They include snakes, lizards, turtles and crocodiles. Most reptiles lay eggs, either soft and leathery or hard-shelled, but...

LET'S EXPLORE The living world

How do we know what is living, such as a flower or a worm, and what is not, such as a stone? Living things grow by making or taking in food of some kind. This process uses energy...

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