Transcript Animal Behavior

Animal Behavior
UNIT 10
Introduction
 Humans have always studied animal behavior
 Knowledge of animal behavior = human survival
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For example, understanding behavior of animals hunted for food
 Behavioral ecology – Studies how animal behavior is
controlled and how it develops, evolves, and
contributes to survival and reproductive success
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For example, does play serve a developmental function?
How does migration contribute to reproductive success
 An organism’s behavior is tied to survival &
successful reproduction
Introduction (Page 2)
 Ethology – Study of behavior & its relationship to its
evolutionary origins
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The study of how animals behave, especially in their native
habitat
 3 Important Ethologists:
 Karl von Frisch – Honeybee communication & waggle dance
 Niko Tinbergen – Fixed action pattern
 Konrad Lorenz - imprinting
2 Levels of Behavioral Studies
 Proximate causes of behavior
“How” questions
 Include the effects of heredity on behavior, genetic-environmental
interactions
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 Ultimate causes of behavior
“Why” questions
 Studies of the origin of behavior
 Utility of behavior in terms of reproductive success
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Behavior, what is it?
 Is it part of an organism’s phenotype or genotype?
 Are hormonal secretions considered behavior?
 Behavior is…
Fixed Action Pattern (FAP)
 Commonly called innate behavior
 Highly stereotypic behavior
 Triggered by a sign stimuli (external stimulus)
 When stimuli are exchanged between members of the same
species, the stimuli are called releasers
 Once begun, the behavior will continue to completion
 Example: Stickleback fish
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Sign stimulus: red underbelly (only males have red underbelly) in
another male’s territory
Behavior triggered: Male attacks red-bellied stickleback fish or model
Stickleback Fish
Which models will produce
an aggressive response?
Learning
 Def – sophisticated process in which the responses of
the organism are modified as a result of experience
 Def 2 – modification of behavior based on specific
experience
 Capacity to learn can be tied to
 Length of life span
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Animals with a short life span (eg Drosophila) have no time to
learn, so these species rely on FAP behaviors
Complexity of the brain
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Dolphins – more convolutions in the brain than any other species,
so an increased reliance on learned behavior
Habituation
 One of the simplest forms of learning
 Def – loss of responsiveness to stimuli that convey
little or no influence
 Example: Cry-Wolf effect
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Although animal may recognize an alarm call for predators
But there will be no continued response if the alarm call is not
followed by an actual attack
 Example 2:
 If hydra is in a container, and the side is tapped = recoiling
 If no harm is encountered after repeated tappings, the hydra
will ignore the tapping – it has habituated to the stimulus
Associative Learning
 Def – Type of learning where a stimulus is associated with
another through experience
 2 Types of Associative Learning
1. Classical Conditioning – Ivan Pavlov
-- Pavlov rang bell whenever dog was fed
-- Soon even if no food was present, dog salivated when bell
was rung
-- Dog was conditioned to associate bell sound with food
2. Operant Conditioning – (trial and error learning)
-- An animal learn to associate one of its behaviors with a
reward or punishment
-- Animal then repeats (rewarded) or avoids (punishment)
the behavior
Operant Conditioning
 B.F. Skinner (1930’s)
 NOT Principal Skinner from “The Simpsons” 
 Rat placed in a cage that contained a lever than when
depressed = food pellet
 At first, rat depressed by accident = food by accident
 Soon, rat associated lever depressing with food appearance
Examples of Operant Conditioning
Imprinting
 Def – Learning that occurs during a sensitive or critical
period in the early life of an individual
 Irreversible
 Example: Konrad Lorenz & Geese hatchlings
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Example of Imprinting: geese hatchlings closely follow their mother
Mother-offspring bonding in animals is crucial to safety & development of
the offspring
Geese hatchlings follow the first thing they see that moves
Lorenz ensured that he was the first moving organism seen by the hatchlings
Hence, the geese hatchlings had imprinted on Lorenz
 Wherever he went, the hatchlings followed
Imprinting (Page 2)
Questions
1. The Stickleback fish is an example of …
2. What are the 2 types of associative learning?
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3. Which type of behavior is unlearned?
4. What type of learning allows an organism to ignore
a particular stimulus?
5. Lorenz attempted to mimic what learning type?
Examples
 Give an example, NOT from the notes, of:
1. Imprinting
2. Operant Conditioning (trial and error)
3. Habituation
4. Classical Conditioning
5. Fixed Action Pattern (FAP)
Social Behavior
 Def - Any kind of interaction among two of more animals, usually
of the same species
 Relatively new field of study
 5 Social Behaviors to focus on:
1. Cooperation
2. Agonistic
3. Dominance Hierarchy
4. Territoriality
5. Altruism
Cooperation
 Enables individuals to carry out a behavior performed more
successfully by a group than individuals
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Hunting in a pack – enables a number of individuals to take
down a larger prey than any individual would be capable of
 Example:
Agonistic Behavior
 Aggressive behavior
 Threats or actual combat to settle disputes among
individuals
 Access to mating, food, or shelter
 Usually involves ritualistic or symbolic behavior, instead of
actual combat
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Dogs will bear teeth to try to scare the opponent
Loser will display submissive behavior (putting tail between their legs
and running away
 Once a dispute has been settled by agonistic behavior,
future encounters will not (usually) involve further
agonistic behavior
Examples of Agonistic Behavior
Dominance Hierarchy
 Pecking Order behavior
 Dictates social position an animal has in a culture
 Alpha male & female in a population
 Beta is next in line in social position
 Alpha is assured of first choice of any resource
 Food after a kill
 Best territory
 Most fit mate
Territoriality
 Territory – area an organism defends & from which other
members of the community are excluded
 Territories are established & defended through agonistic
behaviors
 Territory is important for capturing food, mating
opportunities, and rearing young
 Size of territory is highly variable due to resources
available, and function of the territory
Mating Systems
1. Promiscuous
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No strong pair bonds
 2. Monogamous
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1-male & 1-female
 3. Polygamous
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1 individual mates with several others
Inclusive Fitness
 Def – total effect an individual has on proliferating
its genes BY
1. Producing its own offspring
2. Providing aid to other close relatives to produce offspring
 This behavior is favored by natural selection since it
enhances the the reproductive success of relatives
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Called Kin Selection
Altruism
 Does altruism exist?
 Altuism = selflessness
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Behavior that reduces an individual’s reproductive fitness, but
increases the fitness of the group or family
 For example: when a honeybee stings an intruder, while it
may die, the colony is benefitted
 Kin selection – Potential explanation for seemingly
altruistic behavior
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While the individual is sacrificed, the kin are selected as a result of
performance of the behavior
So while the entire genome is not passed on, enough is passed on for the
behavior (altruism) to be considered an evolutionary mechanism
Altruism
 So does altruistic behavior exist?
 Isn’t the honeybee’s offspring benefiting?
 So the honeybee is not being selfless, but the behavior eventually
results in selection for the organism’s offspring or kin
 A more controversial case:
A father in India decides that he will donate a kidney for
$15,000.
-- Is this altruistic behavior?