Non-genetic Inheritance Flashcards
NON-GENETIC INHERITANCE (EXAMPLE)
UY & BORGIA (2000)
- bower style divergence in Vogelkop bowerbirds
- extremely low genetic divergence
- young males take 4-7y to develop typical adult bower style (culturally transmitted?)
NON-GENETIC INHERITANCE
- factors in 1 individual influence beh/development of another individual (without passing on genes) who may pass influences on in turn
VERTICAL VS HORIZONTAL TRANSMISSION
VERTICAL
- between generations (parents -> offspring)
- similar pattern to genetic inheritance
- in some cases may skip generations (unlike genetic inheritance)
HORIZONTAL
- within generations (peer -> peer)
- impossible w/genetic inheritance
MATERNAL EFFECTS
- offspring’s beh/morphology influenced by mother’s beh/condition
- individual variation better explained by considering mother’s phenotype over individual’s genotype
- NOT genetic transmission
- may be pre/post-birth
PRE-BIRTH VS POST-BIRTH
PRE-BIRTH (BILKO et al (1994))
- rabbit kits’ preferences affected by mum’s diet via prenatal environment
POST-BIRTH (DARWIN (1859))
- female cabbage white butterfly lays eggs on host plant; caterpillars develop there then lay their own eggs on same host plant
- rabbit kits preferences also affected by mum’s diet via postnatal environment (milk/faecal pellets)
SOCIAL LEARNING
- learning facilitated via observation/interaction w/another individual/its products
- observer individual learns from demonstrator individual
- difs from individual learning because it’s heritable
FISHER & HINDE (1949) - spread of milk-bottle opening by UK tits
SOCIAL LEARNING (EXAMPLE)
GALEF & WIGMORE (1983)
- food preference social transmission in rats
- if a dominant rat socially transmits chocolate preference, group likely follows
SOCIAL LEARNING REASONING
WHY LEARN FROM OTHERS?
- may be less time-consuming than individual learning
- may allow new resource exploitation (ie. overcoming neophobia)
- may be less risky than individual trial-error learning
WHY NOT DO IT ALL THE TIME?
- may sometimes be more time consuming waiting for conspecifics than finding out for yourself
- actions of others may be outdated/irrelevant to your needs
- individual learning can sometimes yield higher pay-offs
SOCIAL LEARNING MECHANISMS
LOCAL ENHANCEMENT
- demonstrator presence/beh draws observer’s attention to specific location where beh acquired via individual learning
STIMULUS ENHANCEMENT
- demonstrator presence/beh draws observer’s attention to particular object/stimulus which is then generalised
OBSERVATIONAL CONDITIONING
- observer learns association between stimulus/demonstrator’s beh
IMITATION
- observer copies demonstrator’s beh topography
GOAL EMULATION
- observer attends consequences of demonstrator’s action; uses own method to achieve same goal
SOCIAL TRANSMISSION
VERTICAL (WILBRECHT et al (2002))
- zebra finch father to son song
- non-genetic transmission can mimic genetic transmission
HORIZONTAL
- song sparrow song between territorial neighbours
- non-genetic transmission can occur more widely/rapidly than genetic transmission
- may not produce exact beh copy; non-genetic mutations/errors generate variation
CULTURAL TRANSMISSION
- behavioural techniques transmitted socially; persist over generations
SYMBOLIC REPRESENTATION
- arbitrary symbols use to represent/stand for objects/actions (ie. commands/warnings)
- when 2 initially unrelated stimuli associated w/same event, emergent relation can develop such that they become interchangeable in other other contexts
- human language allows info to be stored/retrieved to persist over long time periods
- uniquely human? NOPE
GENETIC BEHAVIOUR TRANSMISSION
- info carrier = DNA
- action = alters protein production
- fidelity = high
- variation cause = mutation
- mixed input consequence = discrete outcomes
- transmission direction = only vertical (parent -> offspring)
NON-GENETIC TRANSMISSION
- info carrier = actions/imitation/media
- action = alters higher processes (cellular/cog)
- fidelity = variable
- variation cause = replication error
- mixed input consequence = blended outcomes
- transmission direction = vertical/horizontal/both
SUMMARY
- non-genetic beh transmission can occur vertically (down generations)/horizontally (in generations)
- maternal effects involve vertical transmission only; easily confused w/genetic effects (cross-fostering exps help disentangle)
- social learning = horizontal/vertical; occurs via mechanism variety incl. imitation/local enhancement/stimulus enhancement
- symbolic representation (ie. language) = horizontal/vertical; may skip generations; probably rare beyond humans
