1. Nature, Nurture and Human Diversity

2. Part 1:
Behavior genetics

3. Behavior Genetics
Behavior Genetics: study of the effects of our genes (nature) & our environments (nurture) on our individual differences in behavior & mental processes
Focus on 3 main areas:
Evolutionary psychology
Parents, peers & culture
Gender

4. Behavior Genetics
Environment – every non-genetic influence, from prenatal nutrition to the people and things around us.
Behavior geneticists – study our differences and weigh the relative effect of heredity and environment.

5. Codes of Life
Chromosomes – threadlike structures made of DNA molecules that contain the genes

6. Genetic Factors
Each of us have 46 chromosomes – 1 set of 23 from our mothers, and 1 set of 23 from our fathers
The two sets form pairs that contain alternate genes for the same traits
Sometimes one gene is dominate & it “overrides” the recessive gene
Father’s Chromosomes
Mother’s Chromosomes B b
BB = Brown
Bb = Brown
bB= Brown
bb= Blue

7. Genetic Factors Draw a straight, horizontal line on your paper.
Put your hand on your paper so that the tip of your ring finger touches the line.
Does the tip of your index finger also touch the line????
Short index fingers is a recessive trait in females, but a dominant trait in males. Therefore, in a large class, we would have more males with short index fingers than females.

8. Genetic Factors Interlock your fingers.
Which thumb do you have on top? Left or right?
This is also genetic – neither practice nor experience will have an effect.

9. Codes of Life
DNA – deoxyribonucleic acid, a complex molecule containing the genetic information that makes up chromosomes
Genes – biochemical units of heredity that make up chromosomes; a segment of DNA; capable of synthesizing a protein

10. Codes of Life
Genome – complete instructions for making an organism; all genetic material in that organism’s chromosomes

11. The Genetic Revolution
If it were possible, would you take a genetic test telling you which diseases you are likely to suffer later in life?
Do you think it should be legal for employers to use genetic tests in deciding whom to hire?
If you or your spouse were pregnant, would you want the unborn child tested for genetic defects?
If it were possible to instill your unborn child with abilities that would give him/her an advantage, would you?
TR: p.5

12. The Genetic Revolution
Scientists are rapidly identifying genetic codes for various diseases (ex. Huntington’s disease, cystic fibrosis)
Some concerns:
knowledge of a person’s genes could be used against them – James Tatum
Tay-Sachs Diesease - an inherited metabolic disorder in which certain lipids accumulate in the brain, causing spasticity and death in childhood
James Tatum (1993) – postal supervisor who suddenly lost his sight. Granted medical retirement by the Postal Service, the Department of Labor denied it, saying it was a genetic disorder that predated his employment and not covered by his benefits