Understanding:
• Learned behaviour can spread through a population or be lost from it more rapidly than innate behaviour
Learned behaviour describes the process of acquiring new knowledge or skills (which can be improved with practice)
- Learned behaviour is dependent on environmental context and can disappear over time if the context is absent
Innate behaviour describes instinctive responses that are ingrained in an animal (it is encoded in the DNA)
- It can only be modified by genetic change (mutation) which would take place over many generations
Properties of Innate versus Learned Behaviour
Application:
• Feeding on cream from milk bottles in blue tits as an example of the development and loss of learned
behaviour
At the start of the 20th century, two bird species in the UK – blue tits and robins – would feed on cream from milk bottles
- These bottles had no lids, allowing the birds easy access to the top layer of cream
Eventually, aluminium seals were placed over the tops of the milk bottles to close access to this food source
- The blue tit population as a whole learnt how to penetrate the foil lids, whereas the robins as a population did not
This difference in learning development is attributed to the different social organisation of the two bird populations
- Blue tits are flock birds and hence were more likely to observe and pass on newly acquired skills
- Robins are territorial (solitary) birds and could not effectively propagate the information within the population
The ability to pierce the seals and siphon the cream has since been lost from the blue tit population
- Milk is now capped with a plastic lid and is no longer delivered so the situational context is no longer present
- Blue tits have a relatively short life span, so a learned behaviour can be removed from the population rapidly
Learned Behaviour in Blue Tits
