Behavioral Ecology

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Chapter 51

• Behavioral Ecology

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Behavior

• What an animal does, and how it does it.
• Proximate causes
• What stimuli trigger the behavior
• Ultimate causes
• What is the evolutionary significance
• Case why do birds breed in spring?

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Behavior Genes or Environment

• Myth Behavior is either genetic or learned
• Behavior is influenced by both

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Innate Behavior

• Innate instinct behavior
• All organisms of the species exhibit the behavior
  regardless of differences in environment
• Ultimate question (why? question)
• Some behaviors are needed for survival of the
  organism

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Evolutionary approach to Ethology

• Ethologist not only study behaviors but what
  caused the behaviors to arise (evolution)
• Early research focused on how an organism
  performs a behavior without having been exposed
  to the behavior

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Fixed Action Pattern

• FAP sequence of behavior that is unchangeable
  and carried to completion once initiated
• Triggered by sign stimulus

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FAPs and Sign Stimuli

• Many animals use a limited subset of sensory
  information available and behave stereotypically
  in many situations
• Simple stimuli produce repeated results
• Humans respond to entire situations and base our
  actions of more diverse information
• Human infants are exceptions
• Smile at rudimentary drawings of a face
• Sign stimuli are important to organisms
  environment
• Allows the organism to react quickly and
  appropriately
• This allows the animal to be tricked
• Sometimes detrimental to organism mayfly example

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Evolution and Behavior

• Key natural selection will favor behavioral
  patterns that enhance survival and reproductive
  success

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Examples of Research in Behavioral Ecology

• Songbird Repertoires multiple songs
• Why has natural selection favored multiple songs?
• H1 it make older more experienced males more
  attractive to females
• If true males learn songs as they age
• And females prefer males with more songs

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Cost-benefit Analysis of Foraging Behavior

• Feeding costs vs. Feeding Benefits
• Crows and whelks example
• Crows have to open the shell to get to the food
• They fly up and drop the shell on the ground to
  break open the whelk.
• Short drops dont crack the shell
• High drops do
• But flying costs energy

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Learning

• Experience based modification of behavior
• Innate behaviors are modified based on experience
• Vervet monkeys and alarm calls
• Infant monkeys and social confirmation

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Learning vs. Maturation

• Learning change in behavior modified by
  experience
• Maturation change in behavior due to
  developmental changes
• Birds learning to fly

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Habituation

• Loss of responsiveness to stimuli that convey
  little or no information
• Crying wolf effect

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Imprinting

• Learning that is limited to a specific time
  period in an animals life, and generally
  irreversible.
• Lorenzs geese
• Distinguished by a sensitive period

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Bird Song Model for understanding Learning

• White-crowned Sparrow sensitive period for
  developing song is 50 days
• Listens to other birds of the species sing and
  develops a template
• If no song is heard during the 50 days then no
  song is formed
• Template is followed by subsong
• Juvenile bird sings tentative notes of the song
• Deafened birds during subsong fail to reach
  complete song of species
• Subsong is followed by crystallized song
• Once sparrows subsong matches the template the
  song crystallizes

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Bird Song cont.

• Open ended songs of canaries
• Deafened phoebes still learn song

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Associative Learning

• Associate one stimulus with another
• Classical conditioning associate an arbitrary
  stimulus with a reward or punishment
• Pavlovs dog
• Operant conditioning trial and error learning
• Skinner boxes

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Animal Cognition

• Ability to solve problems
• Nervous system takes in vast amounts of
  information and stores and sorts it to reach a
  goal.

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Cognition to move through space

• Kinesis and Taxis
• Kinesis simple change in activity or turning
  rate in response to a stimuli
• Sow bugs and wood lice
• Taxis oriented movement toward or away from a
  stimulus
• Housefly larvae
• Use of Landmarks
• More complex due to arbitrary stimuli memorization

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Migration Behavior

• Regular movement over long distances
• Organisms use three tools
• piloting one landmark to another
• Orientation detects bearing, and travels a
  straight line
• Navigation detecting position and then heading
  toward goal

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Social Behavior

• Any interaction between two organisms, usually
  same species
• How is being social adaptive?
• Living together poses disadvantages
• ?
• ?
• ?

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Agonistic Behavior

• Contest involving two individuals to compete for
  a resource
• Involves rituals and displays
• Baring teeth
• Standing upright
• Staring

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Dominance Hierarchy

• Social group maintained through agonistic
  behaviors
• Establishes a pecking order

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Territoriality

• Territory place an individual will defend for
  breeding, foraging, etc.
• Owners usually win contests Why?
• Ownership is usually proclaimed.
• Singing
• Marking

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Reproductive Behaviors

• Natural selection favors mating behaviors which
  maximize the quantity and quality of partners.
• Courtship behaviors which lead to copulation or
  gamete release

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Sexual Differences in Courtship

• Parental investment time and resources an
  individual spends to produce and nourish
  offspring
• Male competition/Female choice
• Males are usually elaborate to confer genetic
  superiority

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Mating Systems

• Relationship between males and females
• Promiscuous no strong pair bond
• Monogamous one male mating with one female
• Polygamous an individual of one sex mating with
  several of the other
• Most are of the polygyny type (one male many
  females)
• Rare occasion is polyandry (one female many males)

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Mating Systems

• What determines mating systems among species
• Male may leave more viable offspring if he cares
  for a single group of offspring
• Results in monogamy
• Some offspring can fend for themselves at once
• Results in promiscuous behavior
• Some species rely on a male for defense
• Polygamy
• Male parental care is dictated by certainty of
  paternity
• 7 of internal fertilizing males give care
• 69 of external fertilizing males give care

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Social Interactions Depend on Communication

• Signals information transmitted from one
  individual to another that causes a change in
  that individual
• Communication transmission of, reception of,
  and response to a signal
• Singing by birds is a signal this is my
  territory keep out.
• Organisms use
• Visual
• Auditory
• Chemical
• Tactile
• Electrical signals

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Modes of Communication

• Mode is determined by lifestyle
• Nocturnal mammals use auditory and olfactory
• Birds are diurnal and use visual and auditory
  signals
• Humans use auditory and visual signals as well

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Pheromones

• The odor portion of chemical communication
• Common among mammals and insects
• Trailing behavior of ants
• Complex communication systems
• Social bees
• Pheromones maintain social order

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Dance of the Honeybee

• Maximum foraging efficiency relies on the
  communication of good food spots
• Bees communicate using a waggle dance
• Scout bee becomes center of attention by follower
  bees once he returns

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Altruism Case of Inclusive Fitness

• Altruism behaving in a way that reduces your
  own fitness to the benefit of another organism
• I would lay down my life for 2 brothers or 8
  cousins.
• Haldane