Human Behavior and Evolution
Dual inheritance theory
view culture and genes as providing separate (but linked ) systems of inheritance, variation and hence evolutionary change memes are under selection -memes compete for attention survival -more memes exst than can survive -there is variation in abilty of memes to be transmitted (survive) -memes are heritable Just a more complicated inheritance mechanism
what is culture
Informaiton acquried by individual through some type of socail learning transmitted not only by relatives
Primate language
Wild primates can attach meaning to arbitrary sounds specific calls for different types of predators - experiments with vervet monkeys not just limited to primates
Observational learning
learn by wathcing skilled indivudals imitation allows for cumulative cultural change
How is Culture Acquried Socail Facilitation
Activity of one animal indirectly increases the chance that other animals will learn on their own - proxmity and opportunity -every individual figures it out every time
Common misunderstandings Gentic Determinism
All things are determined by genes -not compatible with human learning and culture -so little gentic variaation in modern humans Recall: gentics plus the enviorment shape phentypes -height Behavioral traits are more sensitive to enviromental influenes than morpholgical and physiological traits
Adapted for adaptabilty
Culture allows humans to adapt to a wide variety of enviorments Rapid adaptation because dont wait for genetic changes cumulative learning provides more and better knowledge
False Dichotomies
Culture vs biology Nature vs nurture
how far back does modern human culture extend
From survery on human evolution, you know that this is challenging to answer we do not know how fast psychological mechanisms for observational learning could evolve modern foraging behaviours present by 50,000 - is that enough time for specialized psychological mechanisms for culture to evolve
Primate culture
Good evidence for cultural tradtions within primates Examples: in monkeys, socail faciliatation is thoigh to be the likely mechanism - monekys dont ape -except maybe capuchins Apes show some evidence of observation learning apes do ape
Primate language
In captivity apes can learn to interpret visual signs and communicate with them Kanzi -uses lexigrams combined with gestures -makes requests (sue tickle) -creates novel terms (water bird) -express thoughts (suprise hide) -uses simple rules that specify order between elements (hug roger)
Common misunderstandings All behavioral differences must be rooted in gentic differences
Some are but many arent natural selction shapes learning mechanisms so that behaviour can adjust to local conditions in adaptive ways - soapberry bugs -humans are masters atadjsuting to local conditions
Cultural evolution meme
an idea, beahviour, style or usage that spreads from person to person within a culture -genes and memes influence one another -cultural practices can now alter gene frequences
Language
many languages exist, but all human cultures have the same cpacity for language -abilty , morpholgy for spoken language All languages have common grammar All langauages have ways to define realtionships between words (syntax) Suggests a common underlying strucutre to language and special congnition adaptaion for human language -different from intelligence/ general congnitve abilties
Maladaptation
memes are subject to natural selection -so will only adaptive memes spread -observational learning makes us easily led -memes not spread just from parents to offspring, so memes can spread even if they are not beneficial -can be influenced by maladaptive or bad memes -incorrect, dangerous
NHP language is not human language
no evidene that apeas can learn syntax -elements are not groups into phrases -they provide no inforamtion about timing of events -much of the meaning must be derived from context some contuity apes stuck at level of a 18 month old child human language is a derived trait
culture is adaptive
observational learning is not just a by product of -group living -being relatively intelligent psycholgical mechanism that allow for observational learning likely shaped by natural selction - culture is benficial (increases fitness)
Evolution is watchword
so is human evolution over? depends on your viewpoint -Recall: evoultion is a change in gene grequencies across generations -culture has become an important part of our continued evolution -cultural evolution is faster than biological evolution -evoltionary theory applied to humans need to take culture into consideration