Cultural Diffusion and 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 Number 1115: St. Bernard, Abbey at Clairvaux Growth Accelerated 1155: 400 Monasteries Cistercians in Europe (Grubler 1997) Cistercians in Europe: Cultural diffusion Monasteries Communicated Advanced innovations Water mill Wool manufacture Agriculture/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 examples Reader & 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 Humans Demonstrated in Other Species Chimpanzees, Macaques Whale, Bird Song Cultural Adaptation: Change in culture increases survival, fecundity Not as common Social learning strategies Laland, K. (2004) Learning & Behavior 32:4. Commonly assumed: Capacity for social learning adaptive Gain Information Avoid Cost of Direct Interaction with Environment Laland, K. (2004) Model, Mimic Producer, Scrounger (Information) More Social Learners Reduced Innovation Information on Environment Not as Current More Social Learners Fewer Individuals Interact Directly with Environment Laland, K. (2004) Use Social Learning Selectively Mix with Direct Sampling, Trial & Error Need Strategy for Social Learning When? 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 Food Scrounging So Common, Unproductive Then, 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 Information Individual Learning Hazardous Gorillas: Elaborate Processing of Food Plants Avoid Physical Defenses, Chemical Defenses Individual Learning Costly Laland, K. (2004) When Uncertain Within-Generation Temporal Variation Match Behavior to Current Environment No Obvious Cue to Environment Rats: 2 Novel Foods – Copy Food Choice by Breath Familiar Foods – Little Social Influence on Choice Uncertainty Prompts Social Mimicry Laland, K. (2004) Copy Whom? Directed Social Learning Identity/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 Behavior Starlings, Parrots: Copy Song of Other Species Females 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 Better Cardinal vs Ordinal Copy Good Social Learners (?) Copy Kin – Common in Nature Same Alleles, Same Requirements Advantage