Animal Behavior

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Animal Behavior
Chapter 35
What is Behavior?
• Responses of animals to environmental cues
– What and why it is done
• Controlled by nervous and endocrine systems
• Some are innate
– Heritable, stereotypic, and intrinsic
– Orb spider webs and newborn reflexes
• Some are learned
– Nonheritable, adaptable, and extrinsic
– Bird song and migration patterns
Karl von Frisch
• Initial use of experimental methods in behavior
• Studied senses of bees
• Identified bee communication
– Translated meaning of the waggle dance
– Length and number of waggles = distance
– Angle of waggle run to vertical of hive = angle of
food from sun
Konrad Lorenz
• Founder of behavioral behavior
• Studied instinctive behavior in animals
– Principle of imprinting in ground nesting birds
– Greylag geese experiment
Nikolass (Niko) Tinbergen
• Originated 4 questions to ask about any behavior
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Causation  what are the proximate causes?
Development  what is the ontogeny/development?
Function  what is the survival value?
Evolution  what is the evolutionary history?
• Cornerstone of modern ethology
• Worked with Lorenz on fixed action patterns
Studying Animal Behavior
• Proximate causes examine HOW an animal behaves
– Factors behind a biological system working at a particular
time and place
– Mechanisms and structures within an animal that produce
the behavior
• Ultimate causes examine WHY they behave that way
– Identify and reconstruct evolutionary history of the
behavior
– Purpose of this behavior
– Evolution of the behavior
– Adaptability of the behavior
Innate Behaviors
• Programmed by genes
• Highly stereotyped
• Four categories
– Kinesis: random movement in response to stimulus
• Sow bugs (pill bugs) movement to water
– Taxis: deliberate movement toward or away from a
stimulus
• Stream fish face upstream for food
– Reflex
– Fixed action pattern (FAP)
Taxis
Fixed Action Patterns
• Stereotyped, often complex series of movements
– Response to a specific stimulus = ‘releaser’
– Fully functional 1st time performed
• Completed fully once started
– Not modified by experience
• E.g.: suckling behavior of newborns
egg retrieval of graylag goose
courtship rituals
yawning
Learned Behavior
• Acquired during an animal’s lifetime
• Modified by experiences
• Categories
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Imprinting
Habituation
Associative learning
Problem solving
Spatial learning
• Cognitive mapping
– Social learning
Imprinting
• Occurs during a ‘sensitive’ or ‘critical’
development period
• Imprinting of baby geese on mother was
studied by Konrad Lorenz
Habituation
• Decline in response to a harmless, repeated
stimulus
• Acts as a filter
– Prevents wasting energy on irrelevant stimuli
• Adaptive
Prairie dog warning calls  decrease when homes
near human populations
Associative Learning
• Forms association between
2 stimuli
• Classical conditioning
– Animal learns to perform old
response to new stimulus
• Stimulus 1st, behavior 2nd
• Pavlov’s dogs
• Operant conditioning
– Trial-and-error learning
– Perform behavior to receive
reward or avoid punishment
• Behavior 1st, reward 2nd
• Clicker training
Problem Solving
• Manipulate concepts to arrive at an adaptive
behavior
• Internal memory used as additional
sensory/information source
• Mental trial-and-error
Spatial Learning
• Enables an animal to learn and use
information about its physical
environment
– Bees and wasps use to locate nest
• Tinbergen used digger wasp nests to test
• Cognitive mapping
– Internal representation of spatial
relationships in an animal’s surroundings
– Examples
• Bird food storage caches
• Migration
– Piloting and homing animals
find their way by orienting to
these landmarks
Social Learning
• Involves observing and imitating members of
the same species
– Food washing in Japanese macques
• Female learns and imitated by younger group members
– Calling by vervet monkeys
• Young vs adult
• Eagle vs snake vs any flying animal
Individual Behavior
• Foraging
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Eating
Searching
Recognizing
Capturing
• Communication
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Prairie dog searches for food
in the winter
Visual
Auditory
Chemical
Tactile
• Moving
• Grooming
Warning coloration: behave
conspicuously to further announce
they are dangerous prey
Social Behavior
• Involves interactions with members of the same species
• Types
– Affiliative: promote group cohesion
– Agonistic (aggressive)
• Territorality
• Dominance
– Reproductive
– Parental
• Advantages
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Hunting efficiency
Protection from predators
Energy conservation
Access to mates
• Disadvantages
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Increased competition within group
Increased risk of infection
Risk offspring being killed by group
Risk of being spotted by predators
An aggregation of
ladybird beetles
Male impalas rubbing heads,
exchange scents and establish
relationships
Male lion with his pride
Agonistic Behavior
• Occur over limited resources
• Threats, displays, or combat
– Displays often to minimize injury
• Reinforce social hierarchy
– Stable for periods of time
Silverback male mountain gorilla
– Alpha individual and others understand position
Territoriality
• Establishing and maintaining a space
• Requires maintenance of boundaries
– Olfactory marking
– Singing
– Occasional physical interactions
• Size of territory depends on required
maintenance
• Access to resources and mates
Sexual Reproduction
• Requires communication
– Stereotyped displays (FAPs)
– Sexual dimorphism
– Pheromones
• Conditions for success
– Identify species
– Identify opposite sex
– Identify availability
• Mating systems
– Promiscuous
– Monogamous
– Polygamous
Parental Behavior
• Approaches and care for
young
– Maternal, paternal, both, or
none
• Defense
– Maternal aggression
• Offspring or conspecifics
• Feeding
• Nest building
What is an Ethogram?
• List of natural behaviors in an animal
– Can be individual or social
– Based on natural or semi-natural environmental
observations
• Distinguishes frequencies and durations of
behaviors
– Seasonal and geographic effects
– Gender and development effects
Preparing an Ethogram
• List different behaviors expected to see
– Organize into types
• Solitary or social
• Food or reproductive related
• Affiliative or aggressive
– Multiple individuals need identification codes
• Prepare a chart to allow monitoring
– Break into a given time increment (1-2 minutes good)
– Record everything done as checks and/or letter
designator for each period
• Glossary explains detailed behaviors for other
observers to interpret
Sample Ethogram Glossary
Type of
Behavior
Behavior
Code Description of Behavior
Solitary
Groom self
GS
Animal engages in washing or smoothing its own fur or hair using
tongue or forelimbs
Sleep
S
Animal assumes specie-specific position for sleep, stays on one place
and is not alert to environmental changes
Rest
R
Animal stays in one place but may be roused easily by environmental
changes
Locomote
L
Animal moves from place to place
Eat
E
Animal consumes food it finds in its environment
Look for food
LF
Animal searches the environment for food items
Drink
D
Animal consumes water or other liquids found in its environment
Groom others
GO
Animal engages in washing or smoothing the fur or hair of another
animal in its environment
Play
P
Animal engages in interactions with others that may involve
locomotion, climbing, manipulating objects or other activities that
show a relationship between two or more interacting animals
Fight
F
Animal engages in physical conflict with another animal in its
environment
Steal food
SF
Animal approaches another animal that has located food in the
environment and either by physical force or distraction, removes the
food item form the vicinity of the other animal
Food Related
Social
Aggressive
Sample Ethogram
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