cultural diffusion and social learning strategies

Cultural Diffusionand

Social Learning Strategies

Advance of a leaned trait

Population: (N0, N+), (Naïve, Informed)

Individual Learning (IL) vs Social Learning (SL)

Advance of a learned trait

Transition (N0, N+) (N0 – 1, N+ + 1)

IL: Rate Constant, Independent of N+

SL: Rate, per N0, Increases with N+

SL: Signature of Cultural Diffusion

Individual learning: Cumulative

Social learning: Cumulative

Cultural diffusion: Human examples

End of 11th Century:St Robert Founded First Cistercian Abbey

Slow Growth in Number1115: St. Bernard, Abbey at ClairvauxGrowth Accelerated1155: 400 Monasteries

Cistercians in Europe (Grubler 1997)

Cistercians in Europe: Cultural diffusion

Monasteries Communicated

Advanced innovationsWater millWool manufactureAgriculture/Land clearing (Deforestation)

Cultural Change/Evolution

Opposition to change: Luddites

Fear of new technologies

1811-1816: Luddites destroyed textile machinery

1830: Captain Swing, opposition to threshing machines

Rapidly advancing cultural values

Captain Swing movement: Social learning

Social learning of technology (Grubler 1997)

Cultural diffusion: Non-human examplesReader & Laland (2000) Anim Behav 60:175

Gupppies: Learn Route to Rich Food Patch

SL: Following Past Opaque Partition

Reader & Laland (2000)Not signature of social learning?

Females copied, and learned faster than did males.

Males mixed SL and IL.

Social learning, cultural evolution

Common in HumansDemonstrated in Other Species

Chimpanzees, MacaquesWhale, Bird Song

Cultural Adaptation:Change in culture increases survival, fecundityNot as common

Social learning strategies

Laland, K. (2004) Learning & Behavior 32:4.

Commonly assumed: Capacity for social learning adaptive

Gain InformationAvoid Cost of Direct Interaction with Environment

Laland, K. (2004)

Model, Mimic Producer, Scrounger (Information)

More Social Learners Reduced InnovationInformation on Environment Not as Current

More Social Learners Fewer Individuals Interact Directly with Environment

Laland, K. (2004)

Use Social Learning SelectivelyMix with Direct Sampling, Trial & Error

Need Strategy for Social LearningWhen?

Circumstances for Social Learning?Whom?

Which Individuals “Best” Information?

Laland, K. (2004): When?

When Established Behavior (No behavior) Unproductive

Pigeons: Food in Cartons, Opened by Tearing Paper

Initially, Most Scrounge FoodScrounging So Common, UnproductiveThen, Individuals Learn Socially to Open Cartons

Laland, K. (2004)

When Cost of Asocial Learning High

Searching for Resource Patches (vs Following)Risk of Acquiring Poor InformationIndividual Learning Hazardous

Gorillas: Elaborate Processing of Food Plants

Avoid Physical Defenses, Chemical DefensesIndividual Learning Costly

Laland, K. (2004)

When Uncertain

Within-Generation Temporal VariationMatch Behavior to Current EnvironmentNo Obvious Cue to Environment

Rats: 2 Novel Foods – Copy Food Choice by BreathFamiliar Foods – Little Social Influence on ChoiceUncertainty Prompts Social Mimicry

Laland, K. (2004)

Copy Whom?

Directed Social LearningIdentity/Phenotype of Demonstrator

Affects Pr[Social Learning]

Social Rank Age Association Relatedness Niche

Laland, K. (2004)

Copy the Majority (Conformity)

Mate Choice Copying (Female Choice)Increase Variance in Rep Success of Other Sex

Copy Rare BehaviorStarlings, Parrots: Copy Song of Other SpeciesFemales Favor Complex Song Repertoire

Laland, K. (2004)

Copy Successful Individuals (vs Successful Behavior)

Easy; Which Traits Imply Success?

Red-Winged Blackbirds: Socially Learn Food Preference,Demonstrator Becomes Sick/Stays Well

If Strategy Works, Neutral/Maladaptive Trait May “Hitchhike” with Successful Trait

Laland, K. (2004)

Copy Dominants? Lacks Study

Copy Best vs Copy BetterCardinal vs Ordinal

Copy Good Social Learners (?)

Copy Kin – Common in NatureSame Alleles, Same RequirementsAdvantage