Transcript Chapter_3_Part_1

10/4
• You can get your scantron grade later on in
the day (after my planning 2nd period)
• For warm-up you will be answering a brief
questionnaire. The questions are hard to
answer, but answer with your first instinct.
THERE ARE NO RIGHT OR WRONG
ANSWERS.
• Do not put your name, but put your gender
(male or female) at the top.
10/5
I will be passing scantrons and tests back out
today. The Free Response has not been graded
yet.
We will take about 10 minutes to look over
missed questions.
Happy Friday!!!
Nature v. Nurture
Genetic Influences on Behavior
Behavior Genetics- studies the relative effects of our genes (nature) and
our environments (nurture) on our individual differences in behavior and
mental processes.
This guy will never be….
this guy!!!
Why does Brad Pitt look the way he does? Genes and environment both influence
Evolutionary Psychology
• Seeks to explain why humans act the way
they do
• study behaviors, emotions, and thinking that
seemed to allow our ancestors to survive,
reproduce and send their genes into the
future.
Evolutionary psychologists use
natural selection to explain behaviors.
• What is natural selection?
– (1) Genetic differences between individuals in a
species causes some organisms to be better suited
to their environment. (2)These organisms are more
likely to survive and pass on their genes
(3)These traits become more common in successive
generations.
– Mutations-random errors in gene replication that
leads to a change
Natural Selection at Work
• 1959 Russian Fox
story
• 30 Males, 100
Females- mated- then
kept only tamest of
bunch.
• Mated the tames.
• 40 years later
• New Breed of Fox
• Hand sanitizer?
• Sharks?
Look at our Behaviors…
Can you answer these questions using evolutionary
psychology?
• Why do women experience “morning
sickness” in the first trimester of
pregnancy?
• Why do infants develop stranger
anxiety at about 8-13 months?
• Why do some people have phobias
about spiders and snakes?
Now, the big one?
How and why do men and women
differ sexually?
Of course, there are other
differences….
Survey…..wow….
• 2004 survey of U.S. college students:
“If 2 people really like each other, it’s all right for them to have
sex even if they’ve known each other for a very short time”
60/35
“I can image myself being comfortable with casual sex with
different partners” 48/12
• Survey 18-59 yr olds:
Cited affection as a reason for first intercourse 25/48
Think about sex every day or several times a day 54/19
• Apply to homosexual people?
American lesbians are twice as likely to have partners than gay
men 24/47
•Evolutionary Theory says that our
sex drive indicates our genes way of
reproducing.
•Since a woman usually incubates
and nurses one infant, women pair
wisely while men pair widely…
Gender Differences in Reproduction
Women
• Sure the baby is hers
• Invests lots of time/energy
into each child
• Can only make one baby
per 9 month period
(usually)
Men
• Less sure the baby is his
• May invest very little time and
energy into each child
•Have virtually unlimited
reproductive potential
Therefore, it is in the woman’s best interest to
be choosy about who she mates with, picking
only men who are 1) likely to have good
genes, and 2) willing and able to provide for
her and the child.
How does a women know?
Good looks often indicates good genes.
- Masculinized physical features correlates
positively with better immune function.
-Attracted to mature, dominant, bold, and
affluent men (capacity to support and
protect).
How does a women know?
- Feminized facial features correlate positively a
greater willingness to help raise children.
-So do we look for masculine or feminine
features?
-It depends.
How does a man know?
• Drawn to young, healthy, and ‘fertile
appearing’ women
• Regardless of culture men always seem to
be attracted women whose waists are a third
narrower than their hips (child bearing hips)
Is this always true??
Criticisms of the Evolutionary
Theory
1. Starting with the effect and work backward
to explanation
2. Underestimates cultural expectations and
socialization
3. Does not hold people accountable for
ethical and moral responsibilities for their
sexual behavior
Name three characteristics that
your ideal mate most have:
Gender Differences
• A few stats noting differences: 1. On average women have 70% more
fat, 40% less muscle, and 5 inches shorter
2. Enters puberty 2 years sooner and will outlive her counterparts by 5
years
3. Women are 2x as likely to develop depression and anxiety, and 10x
more likely to develop an eating disorder
4. Men are 4x as likely to commit suicide or suffer from alcoholism, far
more likely to be autistic, color blind, and hyperactivity as well as
antisocial personality disorder in
WHY???
Gender Differences
• Aggression: Men admit to having more
aggression than women in surveys (true).
Male to female ratio in U.S. for murder is 9
to 1!!!!! Hunting, fighting are primarily
men’s activities
• Social Power: Men are perceived as more
dominant, forceful, and independent (true).
Political leaders elected are usually men.
This difference is lessening however.
Gender Differences
• Social Connectedness: women are less concerned with being
individuals and more concerned with making ‘connections.’
*Differences surface early, in children’s play (boys play in large
groups with activities/ girls play in intimate and more social groups)
• *Teen years females spend more time with friends and less time alone
• *Adulthood females tend to be more interdependent and use
conversation to explore relationships
The Nature of Gender
• 7 weeks after conception, you
were distinguishable from
someone of the other sex
• Your sex was determined by
your 23 pair of chromosomes,
the two sex chromosomes
• From your mother you received
an X, and from your father you
received the ONE chromosome
out of the 46 that is not unisex.
• You received an X
Chromosome if you are a girl
and a Y chromosome if you are
boy.
Nature of Gender
• Y Chromosome is a
single gene that
triggers the production
of testosterone- the
most important male
hormone (stimulates
the growth of male sex
organs)
• Females have
testosterone as well
just less of it
Gender Roles
• Gender roles-a set of expected behaviors for
males and for females
• Make a short list of gender roles
• Think about…..
1. Do gender roles reflect what is biologically
natural for men and women?
2. Or do cultures construct them?
“I am Glad I am a Girl
I am Glad I am a Boy….”
Gender and Child Rearing
• Social Learning Theory: The theory that we learn social behavior by
observing and imitating and by being rewarded or punished. Does this
explain gender typing? Ex. “Big boys don’t cry, Alex” “Nichole you
are such a good mommy to your dolls”
• Gender Schema Theory: The theory that children learn from their
cultures a concept of what it means to be male or female and that they
adjust their behavior accordingly.
Genes: Our Biological
Blueprint
Genes: Location and Composition
In the nucleus of every cell we have 46
chromosomes…
Genetic Similarities
Mr. Riggins is :
98%
99.9%
99.9%
Behavior Genetics
The study of the power and
limitations of genes on who
we are.
Twin Studies
What are the
different
types of
twins?
Twins
• Best way to really study
genetics because they come
from the same zygote.
• Bouchard Study
• .69 Correlational coefficient
for IQ tests of identical
twins raised apart.
• .88 raised together.
• Identical twins have a higher
correlation than fraternal
Temperament Studies
• A person’s
emotional
excitability.
• People usually
stay the same
throughout life
• Relaxed babies
tend to be
fearless adults
• Emotionally intense
babies tend to be
emotional adults
Adoption Studies
• Studies show that adoptees’
personality traits are more similar
to their biological parents than
their adoptive families
Heritability
• The proportion of variation among
individuals that we can attribute to genes.
• Does not say what percentage of an
individual’s personality is inherited
• Mark Twain’s barrel example.
Nature v. Nurture
What do you think so far?
Does Nature and Nurture interact
and grow off of each other?
Lets find out soon by examining Nurture in detail….