- Is it nature or nurture that defines us?
o Nature – genes, heredity
o Nurture – everything else that is not genetic (experience, environment) - Both are equally important in shaping who we are. There is also an interaction between the two.
STUDY NOTES ONLY
II – The Nature Component
- 46 chromosomes, 23 pairs.
- Genes carry DNA, which consists of thousands of genes amongst other things. - Genes = Basic Unit of Heredity
- Gene complexes are genes working together to produce a trait or disease. - 4 Nucleotides:
o Adenine (A)
o Thymine (T)
o Guanine (G)
o Cytosine (C)
- The sequence of nucleotides determines what a specific gene does or does not do. o Chromosomes = Books
o Genes = Words
o Nucleotides = Letters
- People are 99.99% similar to each other
- Repartition of the 0.01% difference:
o 5% differences among “races”
o 95% differences within a “race”
- Us compared to:
o Monkey: 95-98% similar
o Mouse: 80%
o Banana: 50%
o Fruit Fly: 44%
o Daisy: 30%
B) Evolutionary Psychology (EP)
- What is EP?
o It is the newest perspective in psychology. Heavily influenced by Darwin and his Theory of Evolution. The main goal for an organism is to survive and transmit genes to the future. Natural Selection (Only the fittest will survive) o Our capacity to adapt is what makes us so strong.
Clark & Hatfield s
- Sent male and female average looking assistants out into public. When they see someone that is attractive, they asked them if they want to go to bed with them. Almost 100% of women said no, and a lot of men said yes.
- According to EP, men and women have the same goal but different strategies. Women would prefer to have a partner to ensure survival of the baby. Therefore they don’t prefer to have recreational sex.
EARN A POINT
If women are not into recreational sex, whom are the men sleeping with?
18 societies that we know of, women are encouraged to have multiple partners.
NOTES + EARN A POINT
C) Behavior Genetics
- Interaction between nature and nurture, people are interested in understanding individual differences.
- Two types of twins: monozygotic twins and dizygotic twins
o 1 egg, 1 sperm, same sex, 100% genetically similar
o 2 eggs, 2 sperm, 2 embryos, same or opposite sex, 50% genetically similar
o If a behavior has a genetic component, then an identical twin should be more similar compared to fraternal.
- If 1 is diagnosed with Alzheimer’s disease, then the other twin has a 60% chance of being diagnosed with the disease. - Fraternal twins are 30% for Alzheimer’s
- Twin studies were criticized; identical twins share the womb, school…etc. They have the same environment.
- The solution was to study twins reared apart, run by Bouchard
- This was eve criticized saying that even random strangers will have similarities if you go through enough stuff.
- Study Identical Twins similarities and compare it to Strangers similarities
o Even though I.D. twins reared apart are less similar than I.D. twins reared together, they are still more similar to each other than fraternal twins reared apart
C.3 Adoption Studies
o An adopted child has two sets of parents:
• Share genes with biological parents
• Share environment with adoptive parents
o Even though adoptive children don’t share the environment with the biological parents, their personality is more similar than the adoptive parents.
C.4 Family Studies
o Family members are more genetically similar than strangers
- Regular siblings: 50% genetically similar
- Parents: 50% genetically similar
- Grandparents: 25% genetically similar
- Cousins: 12.5% genetically similar
- If a behavior has a...