Lecture 9 - Non-Genetic Transmission Flashcards
How do common and black redstart migrate?
Common go to Africa and Black go to Southern Europe
What is the Emien Funnel?
A way of understanding how bird migrate before tracking system existed
- Bids are in a funnel with an artificial sky above them
- Track the scratches on the funnel to see what direction they move and for how long
How is migration driven?
Genetically driven although location is based on behaviour
What factors may explain heritable variation in an individual’s behaviour if not genes?
“Factors acting via one individual that influence the behaviour or development of another individual who, in turn, pass on these influences to another”
What is vertical transmission?
Between generations (parent to offspring)
- Similar pattern to genetic influence
What is horizontal transmission?
Within generations (peer-peer)
- Not impossible with genetic inheritance
What non-genetic factors may explain heritable variation in an individual’s behaviour?
- Parental effects
- Social learning
- Symbolic representation
What are the two kinds of parental effects?
- Maternal effects
- Parental effects
What are maternal effects?
- Offspring’s behaviour or morphology depends on their mother’s behaviour or condition
- Variation between individual’s can be better explained by considering measures of the mother than the genotype of the individual
- May act pre or post-birth
What are the different kinds of maternal effects?
- Inside the womb
- Outside the womb
- Inside and outside the womb
Example of maternal effects inside the womb
Mongolian Gerbil
- Females that are surrounded by males in the womb will be exposed to testosterone. The sex ratio of the offspring in the womb determines the behaviour of the females post birth
- those who have been exposed to high testosterone have late sexual maturity and increased aggression
- these females are more likely to have more male biased sex ratios in their offspring so their daughters will experience the high testosterone during gestation
- It passes through the generations without any genetic effect
Example of maternal effects outside the womb
Cabbage butterfly
- Female lay eggs on host plants where larvae develop
- Where you prefer to lay your eggs depends on where you were laid
Example of maternal effects inside and outside the womb
Rabbits either fed on juniper berries or a control diet
- Mother during gestation feeds on one
- See what the baby rabbits prefer after birth to eat
- Kittens preferences ALSO determined by milk content and mother’s diet
What are paternal effects?
- Offspring’s behaviour or morphology depends on their father’s behaviour or condition
- Variation between individual’s can be better explained by considering measures of the father than the genotype of the individual
What are the different kinds of paternal effects?
- During development
Two examples of paternal development during development
- Onthophagus taurus
- Amount of resources they provide to the children has an influence on offspring development
Males have a black bib under the chin - size relates to social dominance.- X-foster experiment
- Taking eggs from a
subordinate male and
moving into nest with
dominance
- Sparrows
- Subordinate males reared in nests of dominant males grey up socially dominant and vice versa.- Fathers social
environment impacts the
child’s behaviour and
status
- Fathers social
How does social learning differ from self-learning?
Social learning is heritable
Galef & Wigmore, 1983 Animal Behaviour 31, 748-758
When choosing between two novel diets, an ‘observer’ rat prefers that diet previously eaten by a ‘demonstrator’ conspecific with whom the observer has interacted prior to making its choice between diets
How to animals learn songs?
Birds 1 and 2 were able to hear songs during development – birds 12 and 13 were deafened during development.
- yet all four birds develop a similar song structure - learning does not influence song
- → example of song non-learners where song is genetically determines
Vertical transmission in song learning
Father to son
These birds are song learners where they learn song temporally.
- Son 2 - unable to hear fathers song which creates a remarkably different song
Horizontal transmission in song learning
Territorial neighbours
- Neighbouring birds have similar elements to their song
- structure of call more similar to neighbour than non-neighbours
- Unshared song elements among neighbours
- some have influence, some don’t
What elements are required for something to be classed as teaching?
- An individual A, modifies its behaviour only in the presence of a naïve observer, B
- A incurs a cost or derives no immediate benefit
- As a result of A’s behaviour, B acquires knowledge or skills more rapidly than it would otherwise, or that it would not have learned at all
What is symbolic representation?
“Symbolic representation is traditionally defined as the representation of a principal, a nation for example, through a symbol, such as a flag, that evokes particular meanings and emotions about the nation”
What is referential signalling?
- Signal “represents” (or refers to) a subject or concept
- Permits transmission of information without the situation in which the information is relevant occurring
Do animals exhibit transmission via symbolic representation?
High risk of predation
- Response to different predators is different
- Language that is encoding the threats posed by differnt types of predators
- areal vs terestial
- urgency level (proximity)
How do animals learns and hold sets of symbolic representation?
- Able to learn symbols and their meaning
- Arrange them in orders to convey their intentions and what they want (hunger etc)
- → animals can compose and use symbols that fit with language
- Only in individual animals who have been exposed for long periods of time in humans
