Transcript Animal Behavior

Animal Behavior
34.1 Elements of Behavior
34.2 Patterns of Behavior
34.1 Elements of Behavior
• Stimulus and Response
• Behavior and Evolution
• Innate Behavior
• Learned Behavior
• Instinct and Learning Combined
Stimulus and Response
• Behavior: reaction to stimulus in the
environment
– Usually behaviors are performed when an
animal reacts to a stimulus.
• Stimulus: any kind of signal that carries
information and can be detected.
• Response: a single, specific reaction to a
stimulus.
Behavior and Evolution
• Many behaviors are influenced by genes.
• Behaviors may also evolve under the
influence of natural selection.
• Organisms with an adaptive behavior will
survive and reproduce better than
organisms that lack the behavior.
Innate Behavior
• Also called an instinct or inborn behavior.
• Fully functional form without previous use
of it.
• depend on internal mechanisms that
develop as a result of complex interactions
between an animal’s genes and its
environment.
Learned Behavior
• Learning: animals can alter their behavior as a
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result of experience; also called acquired
behavior.
Most animals can learn
There are four major types of learning:
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Habituation
Classical conditioning
Operant conditioning
Insight learning
Habituation
• The simplest type of learning.
• Habituation: a process by which an
animal decreases or stops its response to
a repetitive stimulus that neither rewards
nor harms the animal.
• Ex: Shore Ragworm
Classical Conditioning
• Any time an animal makes a mental
connection between a stimulus and some
kind of reward or punishment.
• Ivan Pavlov’s Experiment
– He studied salivation in dogs; he discovered
that if he always rang a bell at the same time
he fed the dog, the dog would eventually
begin to salivate whenever it heard a bell,
even if food was not present.
Operant Conditioning
• Occurs when an animal learns to behave in a certain way
through repeated practice, in order to receive a reward
or avoid punishment.
• Made famous by B.F. Skinner
– Created a box that when the lever was hit, food was delivered.
After an animal is rewarded several times it knows that it can hit
the lever to receive food. The animal has learned by operant
conditioning.
Insight Learning
• The most complicated form of learning.
• Occurs when an animal applies something it has
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already learned to a new situation.
Common among humans and other primates.
In an experiment a hungry chimpanzee had to
figure out how to reach a bunch of bananas
hanging overhead: it stacked some boxes on
top of one another and climbed.
Instinct and Learning Combined
• Most behaviors result from a combination of
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innate ability and learning.
Imprinting: Some very young animals, such as
ducks and geese, learn to recognize and follow
the first moving object that they see during a
critical time early in their lives.
– This keeps young close to their mothers who will
protect them and feed them.
– Once imprinting occurs the behavior cannont be
changed.
Instinct and Learning, cont.
• Imprinting involves both innate and
learned behavior.
34.2 Patterns of Behavior
• Behavioral Cycles
• Courtship
• Social Behavior
• Competition and Aggression
• Communication
Behavioral Cycles
• Migration: the periodic movement from
one place to another and then back again.
– Ex: birds, butterflies, and some whales
– Allows animals to take advantage of favorable
living conditions.
• Ex: Birds flying south for winter
• Circadian rhythms: behavioral cycles that
occur in daily patterns.
Courtship
• To pass along its genes to the next generation, any
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animal that reproduces sexually needs to locate and
mate with another member of its species at least once.
Courtship behavior is part of an overall reproductive
strategy that helps many animals identify healthy mates.
In courtship, an individual sends out stimuli, such as
sounds, visual displays, or chemicals, in order to attract
a member of the opposite sex.
In some species, courtship involves an elaborate series
of behaviors called rituals.
Social Behavior
• Whenever animals interact with members of their own
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species, as in courtship, they are exhibiting social
behavior.
Many animals form societies.
– An animal society is a group of related animals of the same
species that interact closely and often cooperate with one
another.
– Can often provide survival advantages.
– Often members of a society are closely related to one another.
Related individuals share a large proportion of each other’s
genes. Therefore, helping a relative survive increases the
chance that the genes an individual shares with that relative will
be passed along to offspring.
Competition and Aggression
• Territory: a specific area that
is occupied and protected by
an animal or group of
animals.
– Claiming territory keeps other
at a distance.
• Competition occurs when two
or more animals try to claim
limited resources.
Competition and Aggression, cont.
• Aggression: occurs during competition; a
threatening behavior that one animal uses
to gain control over another.
Communication
• The passing of information from one
organism to another.
• Necessary when involving more than one
individual.
• Visual
• Chemical
• Sound
• Language
Visual Signals
• Used by animals with good eyesight.
• Ex: Cuttlefish
Chemical Signals
• Used by animals with well-developed
senses of smell including insects, fishes,
and many mammals. Many release
pheromones.
• Pheromones: chemical messengers that
affect the behavior of other individuals of
the same species.
– Used to mark territory or signal readiness to
mate.
Sound Signals
• Used by animals with strong vocal abilities
including crickets, toads, and birds.
• Some have evolved elaborate
communication systems.
Language
• The most complicated form of
communication.
• Language: a system of communication
that combines sounds, symbols, or
gestures according to sets of rules about
word order and meaning, such as
grammar and syntax.
• Only humans are known to use language.