Habituation is the gradual reduction in response to a repeated stimulus that is irrelevant or harmless to an animal. When a stimulus such as a sound or sight is encountered repeatedly without negative consequence, the animal will stop responding to it as the stimulus loses its novelty and significance. This allows the animal to ignore unimportant stimuli and conserve its energy and time for responses that are actually important for survival. Examples show how various animals like snails, chicks, prairie dogs, and sea anemones eventually stop responding to repeated stimuli through habituation once they learn the stimuli do not pose a threat.

1. HABITUATION

2. • Habituation is the gradual reduction in response to a
repeated stimulus that is irrelevant to the animal .
• If an animal is repeatedly given with a stimulus which is
not associated with any reward or punishment it ceases
to respond.
• The initial response to a new stimulus is usually one
associated with danger.
• It can cause the organism to flee, crouch and become
immobile or any other form of startle response.

3. • As this stimulus which has no significant meaning to the
animal is repeated it loses its novelty and the animal begins
to ignore it.
• During habituation the animal can sense the stimuli but fail
to respond to it.
• Habituation is a property of central nervous system and not
of the sense organs.
• The benefit of habituation is that it eliminates the response to
a frequently repeated stimulus that has no value in that
particular context, saving time and energy.

4. EXAMPLES FOR HABITUATION
• When a land snail is placed on glass plate, after a
few minutes it projects the stalked eyes and start
crawling.
• If we knock on the plate, immediately it retracts the
eyes and stops moving.
• After a pause for a few seconds , it moves again.
• A second tapping causes retraction, but the snail
emerges quickly and moves on.
• If we continue tapping on the glass plate, the snail
ignores and continues to move, inspite of the
disturbance.

5. • The chicks sees a shadow and drives into the nest
thinking it is a raptor.
• Over time it learns to ignore some shadows
because they are harmless.

6. • The classic example of Habituation was shown
by Tinbergen is of Hawk-goose model
experiment in which when the silhouette was
flown in hawk direction the young chicks of
turkey were alert and tried to escape whereas
when the silhouette move in goose direction the
chicks didn’t react.
• This indicates that the turkey chicks were
habituated with goose shadow since geese are
very common in nature and they often fly over
head.
• But the shadow of hawk was strange for the
chick and hence they were frightened.

7. • Prairie dogs retreat into their holes at the sound of
approaching human footsteps.
• When this occurs many times and the prairie dogs
know the footsteps are not a threat, they no longer
retreat at the sound of footsteps.
• An abused cat is very wary human touch ,but once
it realizes that its new owner pose no threat ,it
becomes used to petting.

8. • A caged hamster becomes frightened when a person
taps on its cage; however, when it realizes that the
taps pose it no danger, it becomes used to hearing
them.
• Ducks in a small pond at a park are scared of people
and fly away when approached.
• They become used to humans over time as they interact
with them and as people feed them , causing them to
realize that the humans are not a threat.

9. • Sea anemones pull food into their mouths.
• If they are stimulated repeatedly with non-food items (sticks,for example)
they will then begin to ignore the stimulus.

10. • Neries pelagica (marine clamworm)-lives in
burrows, stretching out tentacles to trap food.
• If a shadow passes over-quickly withdraws into
burrow.
• Repeated shadows –stops responding to it.

11. • Certain noises in a house cause a
newborn baby to cry, until he or she
becomes desensitized to the noises
and they no longer frighten the
children.
• A turtle draws its head back into its shell when
its shell is touched.
• After being touched repeatedly , the turtle
realizes it’s not in danger and no longer hides.

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