Cultural Evolution

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Cultural Evolution
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Evolution of Computers
1939
1951
1973
1982
1993
2009
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How do Ideas Catch On?

• Ideas usually need to be communicated in order to
  spread. They spread within social networks, so
  some ideas vary across different groups.

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Study by Cullum and Harton, 2007

• Explored how students attitudes changed while
  living in residence halls. Importantly, the
  students were randomly assigned to the different
  residences.
• The students completed surveys that assessed
  their attitudes after spending 2 vs. 13 weeks in
  the residences.
• Did their attitudes become more similar to their
  dormmates over this time?

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Increase in Clustering of Attitudes

• All attitudes showed an increase in clustering
  over the term.
• This was especially true for the attitudes that
  were rated as more important - these attitudes
  were discussed more.
• New subcultures were formed on the basis of the
  ideas that people regularly communicated.

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How do Ideas Catch On?

• Ideas that convey useful information are widely
  discussed and spread.

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How do Ideas Catch On?

• Ideas that elicit a strong emotional reaction are
  more likely to be communicated. People can
  connect with others better when they are
  experiencing similar feelings.

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Did you hear the one about...?

• Study investigated how much the emotional
  intensity of a story predicted whether people
  would relay that story to others (Heath et al.,
  2001).
• The researchers created 12 stories and made three
  different versions of each story, that varied in
  emotional intensity.

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Man finds Dead Rat in Soda Can!

• Mild Degree of Emotion Version
• Before he drank anything he saw that there was a
  dead rat inside.

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Man finds Dead Rat in Soda Can!

• Moderate Degree of Emotion Version
• About halfway through he saw that there was a
  dead rat inside.

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Man finds Dead Rat in Soda Can!

• Strong Degree of Emotion Version
• He swallowed something lumpy and saw that there
  was a dead rat inside.

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• Participants read only one version of each of the
  12 stories.
• They were asked to indicate how likely they would
  be to pass this story along to a friend.

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Likelihood of Passing Story Along

• Participants were more likely to pass along
  stories that elicited strong emotions.

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How do Ideas Catch On?

• People are more likely to prefer, remember, and
  discuss ideas/narratives that contain a minimal
  number of counterintuitive statements.

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• Study by Norenzayan et al., 2006.
• Participants received a list of 18 items to read.
• Some of these items were intuitive and some were
  counter-intuitive.

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• Participants were divided into four conditions
  that varied in the percent of counter-intuitive
  items.
• Entirely Intuitive (100 intuitive)
• Minimally Counterintuitive (72 intuitive, 28
  counterintuitive)
• Equal Frequencies (50/50 Split)
• Maximally Counterintuitive (28 intuitive, 72
  counterintuitive)

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Three minutes after reading the items,
participants were asked to recall them.
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One week later, participants were again asked to
recall the items.
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• Over time, narratives that include a few, but not
  too many, counterintuitive items are recalled
  better.
• This is true of most religions, myths, and
  successful folk tales.

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Number of Counterintuitive Elements in Successful
and Unsuccessful Folktales from the Grimm
Brothers (determined by Google hits also in
Norenzayan et al., 2006)
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Our culture is changing.Some examples from the
USA (see Putnam, 2000)
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People are Participating Less in Civic Affairs
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People are Attending Church Less
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People are Entertaining Less at Home
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Families Eat Together Less Often
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People are Socializing Less
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People are Becoming Less Trusting
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People are Becoming Less Law-Abiding
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Some Causes

• Increased time pressures from families with dual
  incomes ( 10 of change).
• Suburban lifestyles ( 10 change).
• Electronic Entertainment (25)
• Generational Difference (living through WW250)

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Will these trends continue?
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Were Getting Smarter?
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Average IQ has gone up 17 points in past 50 years
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Most Improvement is on Ravens Matrices

• Originally designed as a culture-free
  intelligence test, but ultimately demonstrates
  that there is no such thing.

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Why the Gains?

• The gains appear to be most concentrated in
  analytic and problem-solving skills.
• Part of the story is that people are receiving
  more education than before.

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• A rising professional class added incentives for
  people to receive more education.
• People are exposed to more information as they
  deal with an increasingly complex world.
• In some ways, popular culture is becoming more
  complex too, which should further lead people to
  develop their intellectual skills.

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But Cultures Also Persist

• Despite that cultures continue to change, some
  aspects of them remain distinctive over time.
• One force of persistence is that any new cultural
  ideas need to be incorporated into the existing
  structure.
• A second force of persistence is that people show
  pluralistic ignorance - that is, collectively
  people incorrectly judge the thoughts of others
  based on their actions. They act in ways to fit
  in with their incorrect beliefs about what others
  value and can thus perpetuate the culture.