~Animal Behavior

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Chapter 51

• Animal Behavior

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Behavior-what an animal does and why it does it.

• Ethology study of animal behavior
• Behavior results from both genes and
  environmental factors.
• Causation
• proximate physiological genetic mechanisms of
  behavior
• ultimate evolutionary significance of behavior

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Observation of Magnolia Warbler

• Proximate
• Breeds in spring and early summer
• Hypothesis-effect of increased day length on
  photoreceptors brings on breeding.
• Stimulus results in neural and hormonal changes
  that induce this behavior.

• Ultimate
• Why did natural selection favor this behavior?
• Hypothesis-breeding is most productive or
  adaptive at this time.
• Food more plentiful.

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Innate Behavior

• Developmentally fixed
• Often attributed to genetic programming without
  environmental influence.
• Baby birds opening mouth for food
• Key point-is the range of environmental
  differences among individuals does not appear to
  alter the behavior.

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Innate Behavior

• Fixed action pattern (FAP) sequence of acts
  unchangeable carried to completion
• Sign stimulus these patterns are triggered by an
  external sensory stimulus
• Ex 3-spined stickleback (Tinbergen 73 Nobel)
• Utilizes its color vision to identify
  red-undersided males that try to invade its
  territory.

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Foraging

• Mechanisms animals use to recognize, search for,
  and capture food items.
• Optimal foraging theory
• Feeding costs verses feeding benefits.

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Behavioral ecology concentrates on ultimate
hypotheses

• Animals utilize their genetic variation to
  express behaviors that optimize their fitness
• Natural selection favors behaviors that enhance
  survival and reproductive success.

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Learning-experience based modification of behavior

• Maturation behavior due to developing
  physiological changes.
• Habituation loss of responsiveness to stimuli
  that convey no information simple learning
• Imprinting limited learning within a specific
  time period
  critical period (Lorenz, 73 Nobel)

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Associative Learning

• Connecting two different stimuli
• Ivan Pavlov-Classical conditioning
• Involves associating arbitrary stimuli with
  either a reward or punishment.
• Skinner-Operant Conditioning-trial and error
• Induced manipulation of levers by rats after
  awarding them with food.

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Associative Learning

• classical conditioning Pavlovs dogs
  
  operant conditioning (trial and error)
  Skinners box

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Social behavior

• Sociobiology evolutionary theory applied to
  social behavior (Hamilton)
• Agonistic behavior contest behavior determining
  access to resources
• Dominance hierarchy linear pecking order
• Territoriality an area an individual defends
  excluding others
• Mating systems promiscuous no strong pair
  bonds monogamous one male/one female
• polygamous one with many polygyny one
  male/many females polyandry one female/many
  males

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Agnostic Behavior

• Competition for a resource
• Sometimes simply ritual
• Signifies intent but causes no harm
• Causes social hierarchies to develop in some
  animals
• Dominance hierarchy
• Territoriality

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Mating behavior

• Parental investment-time and resources required
  to produce an offspring.
• Female usually has higher parental
  investment-eggs more costly to produce
• Sexual selection-competition among males for the
  female to choice him.
• Females usually care for young. Paternity not
  always know. Very few have only male paternal
  care.

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Altruistic behavior-reducing individual fitness
to increase that of another

• Inclusive fitness total effect an individual has
  on proliferating its genes by its own offspring
  and aid to close relatives
• Coefficient of relatedness measures inclusive
  fitness by proportion of genes that are identical
  because of common ancestors
• Kin selection aiding related individuals
  altruistically can result in more identical genes
• Reciprocal altruism exchange of aid humans?