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Animal Behaviour (Day 2). AP Campbell Chapter 51. Concept 51.2. Learning establishes specific links between experience and behaviour. The classic debate: Nature vs. Nurture. innate and ( presumably) genetic. environment & experience. Useful tools:
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Animal Behaviour (Day 2) AP Campbell Chapter 51
Concept 51.2 Learning establishes specific links between experience and behaviour.
The classic debate: Nature vs. Nurture innate and (presumably) genetic environment & experience
Useful tools: • Cross-fosteringstudies(animals) • the young of one species is placed in the care of another species • Twinstudies(humans) • the behaviour of identical twins raised apart vs. raised together Both types of study reveal significant contributions by both genetics and environment.
Example: cross-fostering between two mouse species • Peromyscuscalifornicus(California mice) • highly aggressive • extensive parental care • Peromyscusleucopus(white-footed mice) • less aggressive • little parental care
California mice: • highly aggressive • extensive parental care • What do the results of this experiment suggest about the behaviours under study? • Did one mouse have a greater ability to learn the behaviours of the other species? What does this observation suggest? • White-footed mice: • less aggressive • less parental care
How is “learning” defined? Learning isexperience-based modification of behaviour Types of learning: • Imprinting • Associative learning • Classical conditioning • Operant conditioning • Social learning
1. Imprinting • process by which a newborn establishes a behaviour pattern of recognition to another individual or object • important for developing parent-child attachment • parents learn to recognize offspring • offspringlearn basic species behaviours
Case study: Imprinting in Greylag Geese • Infant geese have no innate species recognition. • They instead respond to a sign stimulus when imprinting. • a nearby object moving away from young Similar behaviour is found in many ground dwelling birds
Characteristics of imprinting: • rapid and innate • must occur within a critical sensitive period The importance of forming attachments has been experimentally-demonstrated. Case study: Harry Harlow’s experiments with rhesus monkeys. http://youtu.be/hsA5Sec6dAI Ultimately, why is it important for parents and offspring to form attachments to one another?
2. Associative learning The ability to associate one stimulus with another, or with a behaviour Classical conditioning A neutral stimulus is associated with a reflex-inducing stimulus Operant conditioning A behaviour is associated with an outcome
Classical conditioning: A neutral stimulus is associated with a non-neutral stimulus. • Key: • UCS – Unconditioned stimulus. Stimulates a natural response (UCR). • UCR – Unconditioned response; innate and reflexive. • CS – Conditioned stimulus; initially produces no response (neutral) • CR – Conditioned response The neutral CS is paired with the UCS, which produces the UCR. Eventually, the CS elicits the response, even in the absence of the UCS. The response is now the CR.
Operant conditioning: A behaviour is associated with an outcome. may be positive or negative • Case study: • Monarch butterflies contain poison. • Blue jays learn to avoid monarchs, because they become sick if they ingest them. http://www.youtube.com/watch?v=-63ysqT5nu0
Both types of conditioning can be produced in a lab. Example: Rats can be taught to press levers to release short bursts of heat, while in cold environments.
3. Social learning (observational learning) Social learning occurs through observing other individuals.
http://www.youtube.com/watch?v=KRVxqCo9iW8 Case study: Vervet monkeys • Distinct alarm calls in response to specific predators: • leopards • eagles • snakes • Calls of young monkeys make no distinction between type of threat. • Alarm calls become more specialized as monkeys grow older. • likely through observation of older monkeys
Case study: White-crowned sparrow Learns species-specific song in two stages: • First stage: Critical period (first 50 days) • Young bird must hear the song of adults if it is to ever develop song • Responds more strongly to song of its own species Inference from data: The isolated bird produces a song, but it does not match the song of its species.
Second stage:Fine-tuning through comparison • Juvenile bird sings a tentative song • Compares its own song to that of adults until it matches Inference from data: Exposure to the song is not sufficient. If the bird hears its own song, but is experimentally-deafened, it will produce an erratic song.
What we can learn from the vervet monkeys and sparrows... • There is an innate tendency to produce the behaviour (vocalize) • The behaviour displays plasticity; learning produces fine-tuning over the life of the animal There is interaction between genes and experience
The most complex forms of learning involve cognition. • Cognition – Process of knowing; involves awareness, reasoning, recollection, and judgement • involves situation-specific adaptability • allows problem solving • required in the most complex forms of learning • Many groups of animals appear to exhibit cognition.
As a complex and “intellectually superior” organism... How would you reach the banana?(note: you reeeaaallly want that banana)
Other animals are capable of similar problem-solving: http://www.youtube.com/watch?v=mDntbGRPeEU
Case study: Honeybees can make judgments of “same” vs. “different”.
Summary Experience influences behaviour through the processes of learning. • Imprinting is important for developing parent-child attachments early in life. • Associative learning involves the ability to connect a stimulus with an instinctive response. • Social learning allows organisms to take some of the characteristics of their species. • Many organisms have demonstrated that they are capable of cognition, which is required for complex learning and problem-solving.
Homework Tomorrow... Complete Chapter 51Reading Guide (Concept 51.2) Complete applicable terms on vocabulary sheet Studying Questions of Ultimate Causation: • How does a behaviour aid survival and reproduction? • What is a behaviour’s evolutionary history?