Cultural Evolution

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Cultural Evolution

• Culture Activities, values behavior
• of individual acquired through
• instruction or imitation
• Cavalli-Sforza et al. (1982)
• Science 21819.

2
Cultural Evolution

• Cultural traits learned phenotype
• Cultural transmission Recipient acquires trait
  from transmitter
  
• Cultural evolution Change in frequency of
  cultural traits over time

3
Cultural Evolution

• Some parallels with biological evolution
• Dynamics of traits Population genetics
• Mutation Cultural innovation, or
• random change in trait expression

4
Cultural Transmission

• Change/acquisition behavior or attitude
• Recipient learns
• Transmitter active or passive
• Teaching, conditioning
• Imitation, imprinting

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Dynamics of Cultural Evolution

• Mode Number transmitters/receiver
• Modes
• Vertical Parent to offspring
• Horizontal Within generation (sibs)
• Oblique Non-parents of generation t
• to generation (t 1)

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Dynamics of Cultural Evolution

• Transmitters/receiver
• Many to one (All adults instruct)
• One/few to few (Vertical, horizontal)
• One to many (Oblique)

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Dynamics of Cultural Evolution

• Questions
• Heterogeneity, diversity (polymorphism)
• Within, between populations
• Rate of cultural evolution
• (selection, neutral)

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Predictions Cultural Evolution

• Assume Many to one transmission
• Little cultural diversity
• Difficult for invasion by novelty
• Within-population heterogeneity low
• Between-population heterogeneity low
• Slowest cultural change

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Predictions Cultural Evolution

• Assume Many to one transmission
• Little cultural diversity
• Slow cultural change
• Transmission tribe, social class, caste
• Oblique transmitters apply similar cultural
  pressure to next generation of recipients

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Predictions Cultural Evolution

• Assume One to many transmission
• Little cultural diversity
• Rapid advance of novelty (turnover)
• Within-population heterogeneity low
• Between-population heterogeneity high
• Fastest cultural change

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Predictions Cultural Evolution

• Assume One to few transmission
• High cultural diversity
• Within-population heterogeneity high
• Between-population heterogeneity high
• Intermediate rate cultural change

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Cultural Transmission Humans

• Assume One to few transmission
• Vertical, Parent to Offspring
• Correlate Cultural Traits
• Assume no genetic transmission
• No fitness consequences

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Cultural Transmission Humans
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Cultural Transmission Humans

• Assume Vertical, Parent to Offspring
• Religion Strongest Correlations
• Politics
• Entertainment
• Sports
• Beliefs
• Habits Weakest Correlations

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Cultural Transmission Humans

• Assume Vertical, Parent to Offspring
• Religion Strongest correlations
• Through mother
• Politics Strong correlation
• Through father
• What Evolves? Traits and/or transmission modes?