Cumulative Culture

Cumulative Culture #

Why do humans have so much cumulative culture? #

Mechanism: neurons fire when observing/learning from actions Ontogeny: humans imitate and learn from a young age Function: necessary for survival: collaborative hunting, harming Phylogeny: we are haplorhines (Old World Monkeys), diurnal + group oriented

Study: are humans smarter than apes? #

• compared adult apes to 2 yo humans
• physical cognition
  • space: look for reward
  • quantity, addition of objects
  • causality: production, tools
• social cognition
  • social learning (imitation)
  • communication: gestures, etc.
  • theory of mind: other humans are conscious

Results: humans have similar physical cognition, but much better social cognition. #

• humans are more predisposed to copying, even if it may not be strictly necessary (mirror neurons) whereas apes ignore ‘useless’ tasks

Criteria for Teaching #

1. Teacher modifies behavior in presence of pupil
2. No immediate return for teacher
3. Teacher encourages, punishes, sets examples to modify pupil’s behavior
4. Pupil acquires knowledge more rapidly
   • first observed example: ants tandem walking (2005)
   • mammals: meerkats learn how to eat scorpions without getting hurt
   • more prevalent in captivity

Repertoire of Cultural Transmission Strategies #

• social tolerance: teacher grants learners access to close observation

• opportunity provisioning: teacher allows learners to try difficult or dangerous activities

• evaluative feedback: teacher provides positive or negative signals, commands to stop…

• social/local enhancement: teacher directs attention to task

• direct active teaching: direct, abstract communication and demonstration (human only)

  • rare in non-Western cultures
    • Fiji: use social tolerance

• Fiji: …

  • Vanuatu: no verbal communication in teaching
  • assumption: children learn first through observation

• → verbal scaffolding by adults (WEIRD)

  • ask questions
  • encourage planning
  • praise, encourage
  • instruction and repetition to verbally introduce things
  • joint attention (eye contact)

How Humans Accumulate Culture #

• highly attentive to social cues
• more abstract ideas → more direct active teaching
• imitation allows us to develop specific ideas over generations (poison recipe)
• transmission of culture in large groups more effective & accurate

How We Lose Culture #

Inuit: complex culture to survive harsh northern environment

• 1820’s epidemic: lost oldest hunters, lost technology for kaiaks (spear), bow/arrow, kayaks, …
  • ↳ population loss (less food, no contact w/ other tribes)
  • ↳ relearned when met explorers in 1862

Tasmania: migrated 54k years ago from Australia

• isolated for 12k years
• when discovered in 18th century: simplest toolkit
  • ↳ 24 items, no fire, no fish, no warm clothing…
• compared to very complex tools of Australians: lost most culture due to isolation

Polynesian islands: brain size correlated w/ population size

★ Summary: culture can be lost in small, isolated cultures

Human: