Nature vs. Nurture
Why are people so similar?
What is it?
Explain human behavior/traits by examining the long term
reproductive dis/advantages of said traits and behaviors
Any two humans will have ½% genetic variation
Gender differences in reproductive behavior:
Fact: men and women differ in their willingness to engage in
Men are les concerned about:
Having multiple partners
Knowing their partner really well
Their partner’s level of commitment
Women have way fewer opportunities to bear offspring.
- need to be picky in choosing a mate
- wealth, status and power will protect the child,
promotes her genes
Men can have a thousand kids if they wanted to
- if one partner turns out bad, lots of other opportunities
- want to have as many kids as possible to promote his
- wants to find really fertile women (young, attractive
Problems with Evolutionary Psychology
1. data are correlational 2. “just so” stories and backward reasoning
3. there are variations in human behavior
Why are people so different?
What is it?
An approach to understanding the extent to which
behavior/trait differences can be attributed to genetic
Key ways to investigate:
1. twins raises together
2. twins raised apart
3. adoption studies
~identical twins are much more similar to each other than
Problems with behavior genetics:
1. huge samples (thousands of twins per study)
2. are identical twins raised more similarly than fraternal
twins (same environment)
3. never mention the differences (how many are there?)
4. how similar are you and I?
General findings: identical twins that are raised in separate
homes are remarkably similar to each other
Researchers compare the similarities between:
Identical twins raised apart vs. fraternal twins
raised apart General findings: identical twins are more similar than
- Unaffected by “age at separation”
1. are adopted kids more like their genetic (biology) or
adoptive (environment) parents?
2. How similar are adopted kids to other kids raised in the
Personality is drive