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FIND OUT MORE. Arthropods 107 • Reproduction 101 • Senses 99

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COLONIES

HOW DO SOCIAL INSECTS RAISE THEIR YOUNG?

Most insects take little or no care of their young, but

social insects are an exception. Workers carefully

guard the young and bring them food. Worker wasps

bring chewed-up insects for their grubs (larvae).

Honeybee grubs are fed on honey. These young

insects grow up in a nursery at the heart of the nest.

TERMITE QUEEN WITH

SOLDIERS AND WORKERS 3

Each insect colony contains

several different castes, or ranks.

The queen’s job is to lay eggs –

queen termites are so full of

eggs they cannot move. Large

numbers of non-breeding female

workers tend to the eggs and

maintain the nest. Many insect

colonies also have a defensive

caste of soldiers, armed with

huge jaws or poison.

Most insects live solitary lives, but termites,

ants, and some wasps and bees live together

in large colonies. Members cooperate in

building the nest and finding food.

MONARCH CATERPILLAR 3

Many insect larvae (young) look

very different from the adults.

Moth and butterfly larvae are

known as caterpillars. These feed

on leaves, building up a lot of

weight in a relatively short time.

They then stop feeding and

develop a solid body case in

which they pupate (change) into

their adult body shape.

Compound eye

made of dozens of

six-sided lenses

Antenna

Wing covered with

thousands of tiny,

overlapping scales

4 MONARCH BUTTERFLY

After metamorphosis (the

change from larva to adult), an

adult monarch butterfly emerges from its

pupal case and slowly pumps up its wings.

Like all butterflies, the monarch butterfly

feeds on nectar produced by flowers.

WHAT DO INSECTS EAT?

Insects eat a huge range of foods. Around half are

plant-eaters, feeding on leaves, roots, seeds, nectar,

or wood. Praying mantises are predators, hunting

other small creatures. Fleas and lice are parasites,

eating the flesh or blood of larger animals without

killing them.

HOW DO INSECTS DEFEND THEMSELVES?

Many insects are camouflaged (naturally disguised),

so that predators do not see them. Some species are

armed with stings or foul-tasting poison. Many of

these have bright colours, such as black-and-yellow

stripes, to warn enemies away.

HOW DO INSECTS AFFECT HUMANS?

Plant-eating insects can harm crops and fruit trees.

Wood-munching termites destroy homes and furniture,

while biting insects can spread disease. However,

many insects are helpful to humans – for example,

honeybees make honey, ladybirds eat aphids (which

damage garden plants), and silkworms produce silk.

4 COCKCHAFER BEETLE

In beetles such as this

cockchafer, the front wings have

evolved into tough, rounded

cases called elytra. These protect

the delicate back wings from

damage when the beetle is on

the ground. The elytra are lifted

out of the way as the beetle

takes off and flies.

Pupal case

in which the

butterfly pupated

(changed) from

a caterpillar

Feathery antennae
Elytron (wing
case) fully open
and raised

Back wings unfold

WHERE DO INSECTS GO IN WINTER?

Many adult insects die off in winter.

Their eggs or young survive in sheltered places

and emerge in spring. Some insects survive the cold

by hibernating. Others, such as monarch butterflies,

migrate long distances to avoid the winter chill.

HBUTTERFLY

insects