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ANIMAL BEHAVIOR
Chapter 41
Ethology - the study of animal behavior.
Ethologists are particularly interested
in adaptive behaviors.
Some adaptive behaviors are primarily
innate, while others are primarily
learned.
A. Innate Behavior
Inborn behavior that is largely
genetically determined.
Ex. escape or defensive behaviors
Many innate behaviors are stereotyped
(all members of a species perform the
behavior identically).
Stereotyped behavioral sequences are
called fixed action patterns (FAPs).
Ex. egg retrieving behavior of graylag goose
Once begun, FAPs continue to completion,
even without appropriate feedback.
FAPs are triggered by a specific stimulus
called the releaser (sign stimulus).
What is releaser for graylag goose egg
retrieval?
Releasers can be:
 visual (red underbelly of stickleback fish;
light flashes of fireflies; gaping mouth of
baby birds)
 auditory (sounds of mosquitoes & crickets)
 tactile (male prodding of female stickleback)
 chemical (pheromones)
Supernormal releaser - a model that
exaggerates a releaser; elicits a stronger
response than does the natural object.
Herring gull chicks obtain food
from their mother by
pecking on her bill.
Normal releaser is red spot on
an oblong object.
Supernormal releaser
is an oblong object
that is totally red
or has red stripes.
B. Learned Behavior
Behavior modified by experience.
Types of Learning:
1. Habituation (simplest form)
Animal learns to ignore irrelevant
stimuli.
Young chicks learn to ignore falling leaves &
silhouettes of non-predatory birds.
 Birds learn to ignore scarecrow.
 Mothers learn to ignore noisy children.

2. Classical Conditioning
Animal learns to associate a new
stimulus (conditioned stimulus) with a
reward or punishment.
Dog associates the sound of a bell with food.
[Pavlov’s dogs]
 Ducks associate people with food.


Bears associate cars
with food.
Extinction - loss of a
conditioned response.
3. Operant Conditioning (trial-and-error)
Animal learns to associate one of its
own behaviors with a reward (positive
reinforcement) or punishment (negative
reinforcement).
Used extensively by animal trainers.
Coyote learns to avoid
porcupines.
 Rat learns to press a
lever to obtain food.
 Parrot learns to ride a
scooter.

4. Imprinting
Animal learns during a limited time
period (critical period).

Newly hatched chicks, goslings or ducklings
learn to identify the first moving object
they see as “mother”.
(Konrad Lorenz)
Baby birds learn
species-specific songs.
 Mother goat learns to
identify her kid’s odor.

5. Insight Learning (reasoning)
Animal applies prior learning to new
situations without trial-and-error
activities.
Rare; seen mostly in primates.
Chimpanzee figures out how to stack boxes
to reach bananas hanging from the ceiling.
 Human child figures out how to build a
vehicle by placing a box on roller skates.

6. Latent Learning
Animal uses past observations to
perform a new activity; occurs
without obvious punishment or
reward.
Rats learn to negotiate a maze more rapidly
if they’ve been previously exposed to it.
 Wild animals learn details of their range
during daily explorations.
 Predators learn hunting tactics by observing
their mother.

Most animal behaviors have both genetic
(nature) and environmental (nurture)
components.
C. Types of Behavior
1. Orientation and Navigation
Many animals orient (move in a specific
direction) and navigate (follow a specific
course).
 Male
moths flying toward pheromonereleasing females.
 Bees flying to & from nectar sources.
The most complex orientation &
navigation behaviors are seen in
migrating animals.
Migration – a
regularly repeated
journey from one
specific geographic
region to another.
Bird migrations
Most migrating species use
environmental cues for orientation &
navigation.
 sun & stars
 earth’s magnetic field
 sounds, odors, landmarks
2. Aggression
Often displayed when individuals are
competing for the same resources
(mates, food, shelter, nesting sites).
Aggression is minimized by territoriality
and dominance hierarchies.
 Territoriality - behavior that defends
one’s territory.
Common among insects, birds & mammals.
Territories can be:
 large
or small
 defended against all members of the
species or members of one sex
 defended year round or seasonally
Ownership is displayed by marking
boundaries:
 pheromones
 scent
 urine
 dung
glands
 Dominance
hierarchy - a social ranking of
adult members of the same sex.
Common among vertebrates (domestic hens,
wolves).
3. Mating Behavior
Many animals have elaborate, speciesspecific courtship displays (prevents
interspecific mating).
Mating Systems:
 Monogamy - male & female are paired for a
period of time (days, season, lifetime); tend
to care for & protect young.
Ex. elephant shrews & Bewick’s swans
 Polygamy - member of one sex mates with
several members of opposite sex; members
are usually sexually dimorphic.
 polygyny - 1  / many ’s
 polyandry - 1  / many ‘s
 polygynandry - both sexes have multiple
partners.
4. Altruism
Behavior that increases another’s
fitness at the expense of one’s own
fitness; frequently seen in complex social
groups (honeybees, naked mole rats).
Altruism is explained by kin selection.
By helping a relative survive and reproduce,
the altruistic member ensures that some
of their genes are passed to the next
generation.
D. Group Living
Many animals live in groups.
Advantages
conserve heat or moisture
 better defense (confusion, mobbing)
 enhanced reproductive success
 improved food acquisition
 improved learning

Disadvantages
rapid depletion of limited food supply
 spread of disease

Eusocial animals exhibit 4 characteristics:
 cooperative care of young
 overlapping generations
 division of labor
 communication
 chemical
(alarm pheromone of ants)
 auditory
(sperm whales; elephants)
 tactile
 visual
(grooming behaviors of nonhuman primates)
(round & waggle dances of honeybees)
Round dance indicates that food
is close to the hive.
Waggle dance indicates
that food is far away:
•orientation of the “run”
relates direction
•frequency of waggles
relates distance
Examples of eusocial animals:
Snapping shrimp
Honeybees
Naked mole rats