Ethology: The comparative study of behavior

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Ethology The comparative study of behavior
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Antecedents of Ethology

• From the turn of the century to well into the
  50s, psychology could be roughly divided into
  two camps.
• The purposive psychologists All behavior is goal
  directed, that is, it has a purpose
• William Mac Dougall and later, Edward Chase
  Tolman believed that instinct could be used to
  explain behavior.
• Instinct was believed to be infallible, and
  inexplicable.
• This, of course, is silly

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Antecedents of Ethology

• The behaviorists argued that the controlled
  experiment, and the search for causal
  explanations of behavior was the only legitimate
  source of knowledge.
• Problem
• A behavior must be examined experimentally in a
  controlled laboratory setting
• Takes organism from the environment in which it
  normally behaves
• Typically only learning processes could be
  examined this way
• Thus, the conclusion could be reached that all
  behavior is learned. This is silly too.

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Meanwhile.

• C.O. Whitman and Oskar Heinroth noticed the
  existence of patterns of movement with
  similarities and differences between species that
  correlated with comparable physical characters.
• The same evolutionary thinking that is applied to
  physical traits can be applied to behavior
  patterns.
• e.g. Homologous structures
• Behavior patterns are innate, that is they are
  coded in the genome.

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The birth of Ethology

• Ethology the study of the evolution, development
  and function of behavior.
• Emphasizes the observation of organisms in their
  natural setting, before attempting laboratory
  experiments.
• Ethogram comprehensive, descriptive reports of
  an organisms behavior while interacting in its
  normal environment.

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Konrad Lorenz(1903-1989)

There are mechanism of behavior which evolve in
phylogeny exactly as organs do, so that concepts
of homology can be applied to them as well as to
morphological structures
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Background

• Born in Altenberg, Austria.
• By the age of 4, Lorenz was raising newts and
  ducklings. This fascination with animals was a
  large influence on the course of his life.
• At 19, Lorenz begins a 10 year career as a
  motorcycle racer, while still developing his
  academic career.
• In 1928, K.L. accepted a professorship at the
  University of Vienna.
• During the war, K.L. became a full professor at
  the University of Konigsberg.

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Background

• 1941, K.L. is drafted into the German army.
• 1944, K.L. is captured in Russia. Kept as a
  P.O.W. until 1948. Presumed dead. Writes two
  ethological articles on scrap paper and hand
  raises a starling.
• K.L. restarts his career.
• 1973, together with Niko Tinbergen and Karl Von
  Frisch, K.L. receives the Nobel Prize for
  developing a unified theory of motivation and
  behavior.

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Example The gray goose

• The Behavior When a gray goose sees an egg that
  has rolled out of its nest it retrieves the egg
  in a very stereotyped manner.

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Egg retrieval in the Graylag Goose
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The egg rolling movement

• Goose must see an egg shaped object key
  stimulus.
• The tendency to perform the movement can be
  exhausted
• The longer one waits after exhaustion the easier
  it is to reelicit the act.
• The form of the movement is always the same
  regardless of egg size or shape.

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The Gray Goose

• The goose will continue to perform the movement
  even if the egg is removed during the act.
• After long periods of inactivity the goose will
  perform the act in the absence of a missing egg.
  Leerlaufreakyion-Vacuum activity.

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Key Stimuli

• Environmental events or conditions that the
  animals perceptual mechanisms are tuned to.

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Action Specific Energy (ASE)

• Energy is stored specific to a given act i.e.
  motivational systems run on different energy.
• This energy continues to build up.
• If not released Vacuum Activities take place.
• Example house cat

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Fixed Action Pattern (FAP)

• The genetically programmed core of a species
  typical behavior.
• A highly stereotyped innate movement pattern that
  is based on activity in a specific coordinating
  center in the CNS.
• FAP is released by appropriate key stimuli and
  runs to completion regardless of further
  stimulation (endogenously driven).
• Squirrels and Nuts

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Types of Behaviors

• Appetitive Behavior Those behaviors that place
  the animal in contact with relevant key stimuli.
  Goal Oriented.
• Consumatory Behavior The final phase of a
  motivated behavior that occurs following
  perception of key stimuli.

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Innate Releasing Mechanism (IRM)

• The FAP central coordinating center is normally
  held under inhibition by the IRM.
• When the appropriate stimuli are presented (key
  stimuli) the IRM releases its hold on the FAP
  and the stored ASE is used to produce the
  appropriate chain of behaviors.
• The IRM can be thought of as a lock and the Key
  stimulus as a Key.

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Lorenzs Psychohydraulic Model
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Supra-normal Sign Stimuli

• A supra-normal sign stimulus is one that mimics
  and outdoes normal sign stimuli.

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The Ethological Contribution

• The concept that our sensory apparatus are tuned
  to respond to certain stimuli and not others.
• The concept that how we, and other organisms,
  learn may be dependent upon innate programs.
• That what can be learned is biologically
  constrained.
• That human behavior can be understood though an
  evolutionary perspective.

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Human Ethology

• Humans have F.A.P.s as well
• The eyebrow flash
• Eye rubbing
• Shoulder shrug to ward off attack
• Covering head with hands
• Smiling
• Visual illusions
• F.A.P.s in humans not as rigid as those in other
  organisms.
• Study the sign stimuli that release human F.A.P.s

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Innate Behaviors in Humans

• The eyebrow flash is seen in all cultures.

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Innate behaviors in humans
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Sign Stimuli in Human Behavior

• The corpus adipose buccae in infants.
• Consider sexual dimorphisms as possible key
  stimuli
• Secondary sex characteristics
• Differential deposition of fat.
• Deep voice vs. High voice
• Beard

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Sign Stimuli in Human Behavior

• When threatened there is a tendency to rotate the
  arms inward and raise the shoulders. Males may
  puff up the chest.
• When frightened small muscles on the arms, back,
  and shoulders tense causing the hair to stand
  erect (pyloerrection).

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Direction of hair growth in modern man
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Loss of body hair results in males accentuating
the shoulders artificially
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Sign Stimuli in Human Behavior

• Response to Supra-normal stimuli utilized by
  fashion and cosmetics industry.
• Mascara accentuates the eyes
• Rouge accentuates rosy cheeks
• Lip Stick accentuates full Lips

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Supra-normal stimuli in Humans