1. Nature vs. Nurture

2. Behavior Genetics – The study of the influences of heredity and the environment on behavior – “Nature” vs. “Nurture” Our genetic influences – inborn traits Environmental influences (everything non-genetic)

3. What makes someone… A superior athlete?

4. What makes someone… Funny?

5. What makes someone… Mean, cruel, or evil?

6. What makes someone… Intelligent?

7. What makes someone… Brave?

8. What makes someone… Shy? or outgoing?

9. Is it “nature” or “nurture” ?

10. Adoption Studies Is the child more like the biological parents (“nature”) or adoptive parents (“nurture”)? ??

11. Twin Studies Can compare identical twins with fraternal twins Monozygotic = identical twins (one egg, exact same genetics) Dizygotic = fraternal twins (two eggs, no more genetically similar than other siblings)

12. Twin Studies Can study identical twins separated at birth Same “nature” … different “nurture”

13. Minnesota Twin Studies Dr. Thomas Bouchard & Dr. David Lykken – Conducted famous longitudinal studies on twins at U of M to attempt to determine which characteristics we inherit (nature) and which we acquire (nurture) – Included 8,000 pairs of twins born b/w 1936-1955 – Hypothesis: Even if identical twins were reared apart, they should exhibit the same traits in many areas due to the fact that they share 100% of genetic blueprint. Those traits that differed were due to environmental influences.