Non-genetic inheritance Flashcards
non-genetic inheritance
Divergence of bower style in the Vogelkop bowerbird Uy & Borgia (2000)
- extremely low genetic divergence
- young males take 4–7 years to develop typical adult bower style
- culturally transmitted?
Factors in one individual influence the behaviour or development of another individual (without passing on genes) who, in turn, may pass on these influences to another
vertical transmission
between generations
- parents to offspring
similar pattern to genetic inheritance
in some cases may skip generations (unlike genetic inheritance)
horizontal transmission
within generations
- e.g. peer to peer
not possible with genetic inheritance
maternal effects
Offspring’s behaviour or morphology is influenced by mother’s behaviour or condition
Variation between individuals is better explained by considering the mother’s phenotype rather than the individual’s own genotype
NOT genetic transmission (but easily confused with it)
May act pre- or post-birth
pre-birth maternal effects
inside the womb
kits prefer food that mother had even when cross fostered
Kits’ preferences determined by mother’s diet via prenatal environment
post-birth maternal effects
outside the womb
Female lays eggs on host plant and caterpillars develop there
caterpillars lay own eggs on same plants as mothers
what are kits preferences by mothers diet determined by?
prenatal environment
milk during nursing
faecal pellets deposited in nest
social learning example
Spread of milk-bottle opening by tits in UK (Fisher & Hinde (1949))
social learning
learning that is facilitated by observation of, or interaction with, another individual or its products Hoppitt & Laland (2013)
‘observer’ individual learns from ‘demonstrator’ individual
differs from individual learning because it is heritable
social transmission of food preferences in rats - Galef and Wigmore (1983)
rats either ate chocolate/cinnamon
observers also wanted to eat same food as demonstrator
why learn from others?
may be less time-consuming than individual learning
may allow exploitation of new resources, e.g. by overcoming neophobia
may be less risky than individual trial-and-error learning
why not learn from others all the time?
may sometimes be more time-consuming to wait for conspecifics than find out yourself
actions of others may be outdated or not relevant to your needs
individual learning can sometimes yield higher pay-offs
mechanisms of social learning
- Local enhancement
- Stimulus enhancement
- Observational conditioning
- Imitation
- Goal emulation
- local enhancement
Presence/behaviour of demonstrator draws observer’s attention to specific location where behaviour is then acquired through individual learning
- stimulus enhancement
Presence/behaviour of demonstrator draws observer’s attention to particular object or stimulus which is then generalised
