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FIND OUT MORE. Ear 141 • Eye 140 • Mouth 142 • Nose 143

4 COMPOUND EYES

Insects such as flies have huge

compound eyes made up of many

lenses. Each lens may be used

to build up a larger picture.

Although compound eyes do not

provide increased clarity, they are

extremely sensitive to movement.

Hair-like

projections

increase the

sense of touch

HOW DOES ECHOLOCATION HELP WITH HUNTING?

Hunting bats and dolphins make streams of clicking

sounds, which spread out through the air or water. The

sound vibrations bounce back off objects such

as flying insects or shoaling fish. The

hunter uses its keen hearing to listen

out for the returning echoes. These

allow it to pinpoint the whereabouts of its

victims, so that it can home in on its prey.

HOW DOLPHINS USE ECHOLOCATION TO FIND FOOD

NIGHT PROWLER 1

Many nocturnal predators, including cats, have a reflective

layer at the back of their eyes, which helps to gather light.

Dolphin sends

out click sounds

to locate prey

Sounds

bounce back

off fish

SEEING WITH SOUND 3

Insect-eating bats have very sensitive

hearing that allows them to hunt and

navigate in darkness using echolocation.

They make high-pitched sounds then

swivel their ears to pinpoint the source

of echoes, which lead them to their prey.

ECHOLOCATION

Bats, whales, and dolphins, which hunt in darkness or murky water,

make sounds then listen for echoes to track their prey. The same

technique helps them to navigate and avoid collisions with objects.

Senses

Animals use their senses to find out about the world

around them. Most have the same five senses as humans,

but some have extra senses, such as. ECHOLOCATION.

CAN ANIMALS SEE AT NIGHT?

Some animals can see quite clearly at night even

when there is no moon. The large eyes of nocturnal

hunters, such as owls, are designed to make the most

of very dim light. Many animals active at night also

have extremely good senses of hearing and smell.

DO ANIMALS HAVE BETTER SENSES THAN US?

Many animals have far keener senses than humans.

Sight is our most important sense, but birds such as

falcons have much sharper vision. Some insects can

detect ultraviolet light, which we cannot see. A

bloodhound’s nose is many times more sensitive than

a human’s. Bats, whales, and elephants can detect

very high or low sounds that we cannot hear.

WHICH ANIMALS HAVE EXTRA SENSES?

Some aquatic animals, including sharks, can pick up

tiny electrical signals given off by their prey. It is

believed that many migratory animals can detect

the Earth’s magnetic field to help find their way.

Lens focuses light on to

sensitive cells to help

form a clear image

Antenna

detects scent

particles floating

in the air

Nostrils pick up

scent to lead

cat to prey

Whiskers

enable the cat to feel

movement even in

total darkness

Moths and other

insects make up

most bat prey

TASTING THE AIR 3

Snakes pick up scent particles in

the air with their flickering

tongues. These reptiles do not

have ears, but their sensitive skin

can detect vibrations passing

through the ground.

Heat-sensitive

pits work like

extra eyes

Forked

tongue

picks up

scent particles

Dolphin picks

up returning

echoes from

prey ahead

.

senses