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Animal Behavior: Why (and how) do animals do what they do?. Picture: Animal cognition.net. Aristotle (384-322 B.C.): Observational work in zoology. Anatomy. Embryology. Behavior: Social organization. Characteristics: Vivipary.
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Animal Behavior: Why (and how) do animals do what they do? Picture: Animal cognition.net
Aristotle (384-322 B.C.): Observational work in zoology Anatomy Embryology Behavior: Social organization Characteristics: Vivipary
5/13/08: Natural Selection and History of Animal Behavior Lecture objectives: • Understand Darwin’s theory of evolution by natural selection • Identify the major people and questions that guided the development of the modern study of animal behavior
The views on relationships between species have progressed over time
Darwin set the stage for the study of animal behavior through his theory of natural selection
Evolution by natural selection is inevitable if 3 conditions are met: • Variation: • Heredity: 3. Differences in reproductive success: x x Survival of the “fittest”
Evolution by natural selection acts at the genetic level Peppered moth:Gene for colorhas two alleles (forms): R, r RR, Rr rr
Example of natural selection in action: moths in England during the Industrial Revolution I tawt I taw a peppered moth! 1 Proportion of light moths 0 Brown trunks increase
What would a population look like over timeif one of Darwin’s 3 conditions is not met? • No Variation? • No Heredity? • No Differences in reproductive success?
Biologists often seek to understand behavior through the lens of natural selection“How does this trait promote reproductive success?” Logic: Conditions of n.s. apply to So species have been So the traits we observe today are a So these traits probably exist because
Example of Darwinian approach: How does infanticide by male langurs increase the male’s reproductive success? Tendency for infanticide x x No tendency for infanticide
Example of Darwinian approach: Why might a (former) mother langur be willing to mate with this new male? Tendency to mate x No tendency to mate x
How might building an elaborate bower enhance the reproductive success of male bowerbirds?
The history of the study of animal behavior PavlovThorndikeSkinner Behaviorism ComparativePsychology Aristotle Darwin 1900 350 B.C. 1859 1973 ModernAnimal Behavior Ethology Nobel Prize Lorenzvon FrischTinbergen
Thorndike and Skinner: Operant Conditioning (Trial-and-error learning)
The history of the study of animal behavior PavlovThorndikeSkinner Behaviorism ComparativePsychology Aristotle Darwin 1900 350 B.C. 1859 1973 ModernAnimal Behavior Ethology Nobel Prize Lorenzvon FrischTinbergen
Karl von Frisch: Communication & Sensory abilities in Honeybees
Konrad Lorenz (1903-1989): Instinct, Imprinting & Motivation Form of imprinting:“Westermarck effect”
Niko Tinbergen (1907-1988): What features of the environment do animals respond to? Fixed action patternsEgg-rolling behavior in graylag geese Sign stimuliAggression in 3-spined sticklebacks Experiments!
Behaviorist or Ethologist? You decide! ? “Give me a dozen healthy infants…and my own specified world to bring them up in and I'll guarantee to take any one at random and train him to become any type of specialist I might select – doctor, lawyer, artist, merchant-chief and, yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors.”
Behaviorist or Ethologist? You decide! ? His view: Each animal has its own subjective universe, or way of sensing the world around it. And as a consequence, different animals, even ones that share the same physical environment, might have unique sensory experiences.
The history of the study of animal behavior PavlovThorndikeSkinner Behaviorism ComparativePsychology Aristotle Darwin 1900 350 B.C. 1859 1973 ModernAnimal Behavior Ethology Nobel Prize Lorenzvon FrischTinbergen
The modern study of animal behavior is a synthesis of behaviorism and ethology Behaviorists came to recognize that Ethologists came to recognize that
The history of the study of animal behavior Context: Psychology - Learning “Nurture”Labwork: Mammals, Pigeons PavlovThorndikeSkinner Behaviorism ComparativePsychology Aristotle Darwin 1900 350 B.C. 1859 1973 ModernAnimal Behavior Ethology Nobel Prize Context: Biology - Evolution “Nature”Fieldwork: Insects, bird, fish Lorenzvon FrischTinbergen
Darwin discussion • Variation: What might maintain this? • Heredity: Are all traits hereditary? • Differences in reproductive success: What might make some animals be less successful at producing offspring? x x