L6-8 Flashcards
2 main differences between culture in humans vs animals
humans learn cultural information much faster than other animals and have cumulative cultural complexity
2 types of cultural learning
individual learning and social learning
Cephalization factor
slope of the line of best fit depicting the relationship between body weight and brain weight; allows us to predict the average brain weight of a species
Encephalization quotient (EQ)
actual brain weight/expected brain weight based on body weight
What is greater EQ associated with?
more social species (live in larger groups) and complex social systems (e.g. hierarchy)
3 propositions for why humans have such large brains
fruit consumption, food extraction, social brain (social brain hypothesis)
Fruit consumption proposition for human brain size
primates needed to develop mental maps for when and where fruits grow as they are seasonal and grow in patches
Food extraction proposition for human brain size
primates eat a lot of foods (e.g. nuts) that require ingenuity and creative tool usage to acquire
Social brain hypothesis
cognitive demands inherent in social living (e.g. navigating complex relationship networks) led to the evolution of large primate brains
Neocortex
most newly evolved part of the cerebral cortex that is associated with higher order functions like sensory perception, language, and complex thought
Neocortex ratio
volume of the neocortex/volume of the rest of the brain
Relationship of fruit consumption to neocortex ratio (Dunbar)
unrelated to brain evolution and neocortex ratio
Relationship of food extraction to neocortex ratio (Dunbar)
no significant difference in the neocortex ratio of those that use extractive foraging methods and those that use non-extractive methods
Relationship of group size to neocortex ratio (Dunbar)
larger group sizes tend to be associated with larger neocortex ratios (with humans having the largest)
Cultural brain hypothesis (Muthukrishna et al.)
social learning is a key aspect of the link between brain size and group size; results in increased cultural complexity
Benefits of large group sizes
survival skills (e.g. predation protection, cooperation, hunting, division of labor) and more effective cultural learning
Ratchet effect
cultural information continues to build without losing the earlier information; suggests that human cultural learning is cumulative
Implication of ratchet effect on tools
tools will generally only increase in complexity over time to more effectively accomplish its intention; technology only goes backwards when there’s a massive loss in population
What challenge in cultural learning is faced within large group sizes?
prestige bias
Physiological consequence of larger brains
loss of muscle and intestinal length (which require high energy expenditure) as energy is used in maintaining the brain
2 types of causes that explain cultural variation
proximal causes and distal causes
Proximal causes
something that has direct and immediate effects (e.g. cargo brought by European colonizers to Papua New Guinea)
Distal causes
initial differences that lead to effects over long time periods, usually through indirect relationships
Dynamic social impact theory
individuals influence each other through interacting, leading to clusters of like-minded people separated by geography (i.e. cultures)
Individualistic cultures
variety of practices and customs that encourage individuals to place their personal goals ahead of those of the collective and to consider their distinctiveness
Collectivistic cultures
practices, institutions, customs that encourage individuals to place more emphasis on collective goals (especially one’s ingroup)
Pluralistic ignorance
tendency for people to collectively misinterpret the thoughts that underlie the behavior of others (e.g. due to social undesirability of expressing private thoughts)
How does cultural evolution use the principles of biological evolution?
to explain cultural variability/similarities around the world
How does cultural evolution use mathematical models?
to explain the likelihood of individual learning vs social learning in different environments
2 kinds of research papers
empirical and review papers (e.g. meta-analyses, literature review)
Empirical papers
provides new information to the field based on new data from new studies
Meta-analyses
statistical summary (average of the effect size) of previously published papers to provide the best estimate of what the true effect size should be
Literature review
summary of existing information reorganized into a novel framework
Difference between the purpose of meta-analyses and literature review
summarizes current knowledge; clarifies the structure of existing knowledge
Phylogeny tree
reconstructed ancestry tree that visually represents cultural evolution (i.e. how different species emerge) and diversity based on shared characteristics applied to different aspects of culture (e.g. language)
