Human Growth and Development

Lecture 3 - Biological Beginnings, Nature and Nurture

1/17/06

Evolutionary Perspective
- Natural Selection
  - Central Idea: S/He who ends up with the most babies wins
  - Organisms produce more offspring than the environment can support
  - Only offspring best suited to that environment survive long enough to reproduce
- Evolutionary Psychology
  - focus on behavior
  - Why haven’t things like Alzheimer’s and arthritis been selected out?
  - Bidirectional View
Genetic Foundations
- Chromosome - made up of genes
- Gene - "unit of heredity information"
  - I.e. gene for blue eyes
  - made up of DNA
- 46 Chromosomes (usually)
- Sperm and egg cells only have 1 set of 23 chromosomes each.
- Dominant and Recessive Genes
- Genotype
- Phenotype
- Polygenetic inheritance
- Reaction Range
- Canalization
- Behavior Genetics
  - Study extent to which behavior is inherited
  - Identical Twins (monozygotic)
  - Fraternal Twins (dizygotic)
  - Problems?
- Sex-linked Genes
  - located on the X chromosome
  - females have a "backup," males don’t
  - color blindness
  - some kinds of baldness
  - hemophilia
- Sex Chromosome Abnormalities
  - Klinefelter Syndrome - XXY
  - Fragile X
  - Turner Syndrome - XO
  - YO
  - XYY Syndrome
- Gene-Linked Abnormalities
  - Phenylketonuria (PKU)
  - Sickle-cell anemia
- Genetic Counseling...
Heredity-Environment Interaction
- Intelligence
  - Genetics
  - Environment
- Heredity-Environment Correlations
  - Passive genotype-environment correlations
  - Evocative genotype-environment correlations
  - Active (niche-picking) genotype-environment correlations
- Shared & Nonshared Environmental Experiences

Human Growth and Development
Last updated: 1/16/06