Animal Behavior

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Animal Behavior
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What is behavioral ecology?

• Behavioral ecology studies how behavior is
  controlled and how it develops, evolves, and
  contributes to survival
• Behavior is everything an animal does and how it
  does it
• Ethology is the scientific study of how animals
  behave, especially in natural environments

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Understanding Behavior

• Questions that must be asked to understand any
  behavior
• What is the mechanistic basis of the behavior
  (chemical, anatomical, and physiological
  mechanisms)?
• How does development of the animal, from zygote
  to mature individual, influence behavior?
• What is the evolutionary history of the behavior?
• How does the behavior contribute to survival and
  reproduction (fitness)?

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Fixed Action Patterns

• One type of behavior studied by ethologists is
  the fixed action pattern (FAP)
• An FAP is a sequence of unlearned behavioral acts
  that is essentially unchangeable and, once
  started, is usually carried to completion
• Triggered by a sign stimulus (some external
  sensory stimuli that triggers the behavior
• Example Aggressive behavior in male stickleback
  fish in response to the red underside of an
  intruder fish

The following models were used to induce
aggressive behavior. The realistic model did
nothing, but the shapes with red bottoms caused
aggressive behavior
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Imprinting

• Imprinting is a type of behavior that includes
  both learning and innate components and is
  irreversible
• There is a limited phase in an animals
  development which is the only time when certain
  behaviors can be learned (sensitive period)
• Incubator-hatched goslings imprinted on scientist
  (Konrad Lorenz) during first few hours of life
  and followed him

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Nature vs. Nurture?

• In biology, its not an either/or scenario
• Genes and the environment both influence behavior
• Some behaviors can be altered based on the
  environment (still set behavior, but the behavior
  changes based on changing external conditions)
• Other behaviors are virtually identical in a
  population . . . regardless of external stimuli
• Innate behavior is behavior that is
  developmentally fixed, regardless of the
  environment

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Directed Movements

• Animal movements can have substantial genetic
  influence (directed movements)
• Examples
• Kinesis
• Taxis
• Migration

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Directed Movements

• Kinesis a simple change in activity or turning
  rate in response to a stimulus
• Example pillbugs live best in moist conditions
  they move around more in dry areas and less in
  moist/humid areas
• More movement increases likelihood they will
  encounter a moist area

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Directed Movements

• Taxis a more or less automatic, oriented
  movement toward or away from a stimulus
• Example fish swimming against the current
• Migration

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Animal Signals Communication

• Many interactions between organisms are a result
  of sending and receiving information that alters
  behavior
• A signal is a behavior that causes a change in
  another animals behavior
• Communication involves the transmission of,
  reception of, and response to signals between
  animals

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Types of Communication

• Chemical Communication
• Pheromones chemically emitted odors that may
  attract organisms from several kilometers away.
  Particularly important in reproduction behavior
• Auditory Communication
• Bird songs and insect songs are also important in
  reproduction
• Drosophila males produce a characteristic song
  by beating their wings

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Environment Genetics

• Environmental factors, such as the quality of the
  diet, the nature of social interactions, and
  opportunities for learning can influence the
  development of behaviors in every group of
  animals
• Example Variations in diet led to rejection of
  mates in Drosophila

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Learning (start here)

• Learning is the modification of behavior based on
  specific experiences
• Learning has a large range of expression
• From simple imprinting to learn to recognize a
  parent to extremely complex . . . i.e. AP Biology
• Habituation loss of responsiveness to stimuli
  that convey little or no information
• If you poke a hydra, it will contract into
  itself. Yet, if you keep poking the hydra (not
  very nice), eventually it will ignore the stimuli
  if it is not harmed
• Evolutionarily it is believed this prevents
  organisms from wasting energy on stimuli that are
  not pertinent to survival or reproduction

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Learning

• Spatial Learning the modification of behavior
  based on experience with the spatial structure of
  the environment, including the location of nest
  sites, hazards, food, and prospective mates
• Example Organisms being able to recognize
  landmarks
• This is a much more sophisticated form of
  learning because it involves learning stimulus
  that may vary in an environment

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Learning

• By putting together several landmarks in a
  spatial learning scheme, organisms could traverse
  to a variety of different environmental locations
• Another possibility is the use of cognitive maps,
  an internal representation of the surrounding
  environment with spatial relations to each other
  (a mental map)
• Sometimes it is difficult to determine if an
  organism is using spatial learning or relying on
  a cognitive map

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Associative Learning

• Another type of learning has to do with an
  organism learning behaviors based on experiential
  factors
• Associative learning is the ability of many
  animals to associate one feature of the
  environment with another
• Example Associating eating one type of insect
  with a bad taste

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Types of Associative Learning

• Classical Conditioning
• an arbitrary stimulus is associated with a reward
  or punishment
• Example Pavlovs Experiment
• Operant Conditioning
• trial-and-error learning
• Example Mouse eating distasteful caterpillar OR
  a coyote getting a face full of quills from a
  porcupine

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Cognition Problem Solving

• Some behaviors show more sophisticated levels of
  learning
• Cognition is the ability of an animals nervous
  system to perceive, store, process, and use
  information gathered by sensory receptors
• Cognitive ethology studies how an animals
  nervous system and behavior interact
• Example chimpanzees cracking open oil palm nuts
  by observing an experienced chimpanzee performing
  the task

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Natural Selection Behaviorism

• The genetic components of behavior evolve through
  natural selection
• Natural selection favors behaviors that increase
  survival and reproductive success
• Foraging behavior Balance between benefits of
  nutrition and cost of finding food (predation,
  energy, etc.)
• Cost-benefit analysis
• Mating systems and parental care
• Most animals are promiscuous (no strong
  pair-bonding relationship)
• Monogamous
• Polygamous (usually single male with many females)

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Reasons for mating systems

• Finding mates, caring for young, and passing on
  genetic traits are strong determining factors in
  mate selection
• Monogamy is important in birds. It takes a lot
  of work to feed and care for young that are
  relatively helpless. Both male and female are
  needed to provide for young, so they stick
  together
• Polygamy occurs when the young can care for
  themselves at a young age. Males seek to
  maximize reproductive success
• There are many other factors that influence
  behavior

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Sexual selection

• Reminder
• Intersexual selection one sex chooses a mate
  based on some characteristic of the other sex
  (female usually makes the selection and males vie
  for selection)
• Intrasexual selection competition of one sex
  for mates (males fight each other to win a
  female)

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Evolutionary impact

• A lot of male behaviors, or anatomical features,
  may be due to intersexual selection
• Females choose traits and those traits become
  selected for
• Peacock feathers, birdsong, long eyestalks in
  male stalk-eyed flies
• Male behaviors, or anatomical features, may also
  be due to intrasexual selection
• Agonisitic behaviors are ritualized competitions
  that teach males to fight for mates

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Altruism Inclusive Fitness

• Most social behaviors are selfish
• Altruism when an animal behaves in a way that
  reduces its individual fitness but increases the
  fitness of the other individuals in the
  population
• Example squirrels alarm call, worker bees
• Helps close relatives (children, siblings, etc.),
  thereby increasing the individuals genetic
  representation in the next generation (saving
  close relatives) inclusive fitness

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Reciprocal Altruism

• Sometimes animals will behave altruistically to
  other animals that are not related
• This behavior can be adaptive if it aids the
  animal in the future, reciprocal altruism
• Reciprocal altruism is rare in animals
• Limited largely to same species that live in a
  social group, but not always related (chimpanzees)

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Social Learning

• In addition to genetic and environmental
  influences, learning can be influenced by social
  contact
• Social learning is learning from observing the
  behaviors of others
• Social learning forms the roots of culture
• Mistakenly, we believe social learning only
  occurs in humans. It may also occur in animal
  populations

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Social Learning

• Example Mate choice copying
• Female guppies have been seen to mate with males
  that have been successful in attracting other
  females
• Example Alarm calls
• Monkeys learn different calls to symbolize
  different predators (leopards, eagles, snakes)
• When young these calls are inaccurate (any bird
  may be given the eagle call
• Yet, as they mature and learn to discriminate
  species, their calls become more accurate

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What about us?

• Biology is not limited to the study of just
  animal behaviors
• Some scientists study how evolutionary theory
  applies to human culture, sociobiology
• This field is highly controversial
• Could be used to justify status quo human
  societies (caste systems)
• Risk of oversimplification