evolution, genetics and experience

• Cartesian Dualism


  The philosophy that the universe is composed of two elements: physical matter (body) which behaves according to the laws of nature, and human mind (soul, self or spirit) which lacks physical substance, controls human behavior, obeys no natural laws, and is thus the appropriate purview of the Church.
• Most of the early North American experimental psychologists were totally committed to the nurture (learning) side of the nature-nurture issue, while European ethology focused on the role of nature, or inherited factors, in behavioral development.
• The emergence of epigenetics led to a shift from dichotomy to interactions in exploring the possibilities of the human mind and behavior.
• Evidence for Darwin's theory of evolution

  • Evolution of fossil records
  • Structural similarities among living species
  • Changes brought about in domestic plants and animals by selective breeding
• Natural selection


  The process by which the members of each species with heritable traits associated with high rates of survival and reproduction are the most likely ones to be passed on to future generations.
• Social dominance hierarchy


  Dominant males copulate more and dominant females are more likely to produce more and healthier offspring, which increases their effectiveness in passing on their characteristics to future generations.
• Courtship display


  An intricate series of courtship displays precedes copulation, and copulation may not proceed if one of the pair fails to react appropriately to the signals of the other.
• Spandrels


  Incidental nonadaptive evolutionary by-products that serve no adaptive function.
• Exaptations


  Characteristics that evolved to perform one function and were later changed to another function.
• Homologous structures


  Structures that are similar because they have common evolutionary origin.
• Analogous structures


  Structures that are similar but do not have common evolutionary origin.
• Evolution of the human brain

  • It has increased in size during evolution
  • Most of the increase in size has occurred in the cerebrum
  • An increase in the number of convulsions (folds on the cerebral surface) has greatly increased the volume of the cerebral cortex (the outermost layer of cerebral tissue)
• Gregor Mendel, an Augustinian monk, sent manuscripts that contained the answers to Darwin's questions
• Alleles


  The two genes that control the same trait
• Homozygous


  Organisms that possess two identical genes for a trait
• Heterozygous


  Organisms that possess two different genes for a trait
• Dominant trait


  The trait that appeared in all of the first-generation offspring
• Recessive trait


  The trait that appeared in about one-quarter of the second-generation offspring
• Genotype


  The set of genes found in an organism's DNA responsible for a specific trait
• Phenotype


  The physical expression of an organism's genes
• Ontogeny


  The development of individuals over their life span
• Phylogeny


  The evolutionary development of species through the ages
• Selective breeding of "maze-bright" and "maze-dull" rats


  Tryon trained a large group of rats to run a complex maze, then bred the "maze-bright" and "maze-dull" rats
• Phenylketonuria (PKU) is a neurological disorder caused by a single-gene metabolic disorder
• Development of birdsong


  1. Sensory phase: birds form memories of adult songs they hear

  2. Sensorimotor phase: juvenile males begin to twitter subsongs, which are gradually refined into adult songs
• Behavioral geneticists study individuals of known genetic similarity, such as comparing monozygotic and dizygotic twins, to assess the relative contributions of genes and experience to the development of differences in psychological attributes