Section B Flashcards
Define culture
“information capable of affecting individuals’ behavior that they acquire from other members of their species through teaching, imitation, and other forms of social transmission.”
- Richerson and Boyd (1985)
Explain why culture is important for psychology
- Culture explains much of the human behavioural variation around the globe
- for example, Nisbett & Cohen’s ‘culture of honour’ research: Real world implications - - historically, more violence and murder in American South than North
– Control/Insult conditions observed distance at which Northern and Southern subjects gave way to confederate
- Southerners in Insult condition give way at significantly shorter distance
– Southerners show culturally acquired beliefs and behaviour consistent with protecting personal honor
- Why? The south, more than north, are descendants of herders. Honour is more important for protecting your cattle than your wheat - Culture impacts cognition and our culture is WEIRD
WEIRD cultures are outliers in…
- cooperation and fairness
- moral reasoning
- categorization and inferential induction
- spatial reasoning
- visual perception - e.g. Muller Lyer illusion - Culture is the key human survival strategy
- e.g. Burke and Wills Australia expedition, not culturally adapted for environment, local Aboriginal people had culurally transmitted means of survival e.g. how to process plants to remove poison
Explain why and under what conditions social
learning is adaptive
Why?
Social learning ‘fast and frugal’ adaptation
- individual learning imposes a cost (time + energy)
- by imitating, an individual gains benefits of behaviour & avoids learning costs
- works best when individual learning is costly and environment changes too fast for genetic adaptation (but not so fast that culture cannot track the changes either)
When?
a) human survival strategy hard to learn as individuals. Compare chimps and humans. Chimps’ calories from collected foods, easy to learn distribution./extraction. humans gain significant calories from hunted foods - technically difficult, RF for individual learning highly random. Thus culturally acquired knowledge (socially learnt) crucial
b) rapidly varying environment. to survive in rapidly changing environment, best strat is to rely on imitation, where some individuals find novel ways to deal with situation and others can imitate them, then the lucky/smart few in next gen can modify/improve strategies.
Explain conditions for emergence of cumulative cultural evolution
Conditions:
Cognitive capacity for cumulative cultural copying
- technical intelligence; theory of mind; selective social learning; over-imitation; teaching; language
Culture as information commons
- Asocial learners produce information
- Imitators are info scroungers
- Game theory prediction: at equilibrium net benefit = nil
When?
c) cumulative cultural evolution /”ratchet effect”
- individuals learn to improve on existing cultural traditions
- allows net befits to accrue to group of learners
- cumulative effects result in NET BENEFIT to fitness for group as they BUILD on prior innovations
e.g. compare chimp cultural history to human in terms of innovation, proliferation
d) Demography and social structure
- crucial factor in cumulative cultural evolution to maintain cultural info, or it is lost at faster rate than is copied/stored
- Population density
- population size
- kin structure
Discuss analogies between genetic and cultural evolution
Attribute:
discrete units
Genetic sys:
nucleotides, codons, genes & individual phenotypes
Cultural sys:
cultural traditions, memes, ideas, artefacts, words, syntax grammar
Attribute:
replication
Genetic sys:
transcription & reproduction
Cultural sys:
teaching, learning & imitation
Attribute:
dominant mode/s of inheritance
Genetic sys:
parent-offspring (mendelian) or clonal
Cultural sys:
parent-offspring, peer groups, generational, teaching (sometimes biased e.g. prestige)
Attribute:
horizontal transmission
Genetic sys:
RARE; many mechanisms (e.g. hybridization, viruses, transposons & insects)
Cultural sys:
COMMON; borrowing or imposition
Attribute:
mutation
Genetic sys:
many mechanisms (e.g. slippage, point mutations, mobile DNA)
Cultural sys:
innovation, mistakes, vowel shifts
Attribute:
selection of favoured variants
Genetic sys:
natural selection of traits that enhance survival & reproductive fitness
Cultural sys:
natural & cultural selection (e.g. societal trends & conformist traditions)
Attribute:
rates of evolution
Genetic sys:
SLOW; many generations
Cultural sys:
FAST or SLOW
3 principles for natural selection according to Lewontin
- phenotypic variation - different morphologies, physiologies, behaviours btwn individuals in a population
- differential fitness - different phenotypes have different rates of survival & reproduction in different environments
- fitness is heritable - correlation btwn parents and offspring in the contribution of each to future generations
Explain prestige and conformist biases
prestige bias = Copy the most successful individual/s - follow the leader
– Direct - based on success in relevant task, or
– Indirect - based on some indicator trait, like social status
* Can lead to runaway selection - if many copy most prestigious individual, can shift what population is doing overall
conformist bias = Copy the most common type – follow the majority
- Highly stable - slow rates of change
- Herding – e.g. financial markets
- Group markers
- Language
Anti-conformist bias?
– Copy what is new/different
Explain context vs content biases
context biases:
- cognitive biases evolved to let us navigate cacophony of social info around us
- tells us WHO or WHEN to copy
- e.g. prestige or conformist biases
content biases
- determine WHAT we copy
- successful memes and cultural attractors
Define memes per Dawkins
Cultural replicators, conveying a unit of cultural transmission or of imitation.
Discuss disanalogies between memes and genes/genetic & cultural evolution
1. Can’t point to memes in brain
- what are the units of memes? Genes coded in DNA; where are memes stored?
2. No clear genotype/phenotype distinction
- genotype = stored info; phenotype = upon which selection acts
3. Lamarckian inheritance - organism can pass to offspring characteristics that parent acquired during its lifetime
- in bio, genotype determines phenotype
- in culture, genotype and phenotype may affect each other?
4. Non-random mutations
- we’re intentional agents, and generate memes to suit needs and wants
5. Low fidelity transmission
- info loss - cultural transmission is noisy
- blending - not restricted to copy 1 ancestor like genes; may copy many ‘ancestors’ with horizontal & vertical transmission (unlike genes); no identity by descent
6. Reconstruction (not copying) and cultural attractors
- ideas interpreted & reconstructed, not copied - explaining culture = identifying cultural attractors produced by cognitive biases
Replies to disanalogies between genes and memes?
-
Still disagreement over what defines a gene
Neuroscience may offer answers in future - e.g. mirror neurons, semantic mapping of brain
5, 6. copying fidelity & cultural attractors
Cultural attractors create discrete units of culture
* Attractors are stable, despite noisy
transmission
* “the resulting population dynamics and the final distribution of mental representations are closely approximated by discrete-trait replicator dynamics model”
Population thinking view:
Accurate replication needn’t be at level of the gene/meme
* Conformist bias = long term stability at the population level
* Prestige bias = blending of most successful strategies results in adaptive evolution
* Transmission fidelity can be very low at individual level but high at population
level
– Henrich and Boyd (2002)
- “Units” unlike genes - not particulate or directly copied
- major contribution of Darwinian thinking is in viewing species, not as
‘essential types’ but populations of organisms carrying a variable pool of inherited information through time - same is true of culture
- And if information is transmitted in populations down generations, we can ask meaningful questions about cultural evolution through time
Compare micro & macro evolution of culture and biology
Culture
micro-evolution
- memetics
- competing memes in a population
macro-evolution
- relationships between cultures
- long-term patterns of change
Biology
micro-evolution
- population genetics
- competing genes in a population
macro-evolution
relationships between species
long term patterns of change
Define strong reciprocity
I.e. altruistic behaviour that imposes a greater cost than benefit to the actor - reduces fitness at individual level
Group selection explanation for strong reciprocity
High morality being prevalent among individuals in a group gives advantage to cooperation, an essential human survival strat, over other groups. Thus high morality (strong reciprocity) is selectively advantageous (Darwin)
Arguments against genetic group selection
Selection between groups must keep pace with selection on individuals within groups
– Requires large genetic differences between neighbouring groups
– Requires very low rates of migration between neighbouring groups
– Requires high rates of group extinction
