E3 Innate and learned behaviour

Pp 471 - 480

What is Behaviour?An activity or action

that helps an organism survive in its environment.

Example; linking, eating, running, walking, flying, sleeping etc.

Animals behave in certain ways for four basic reasons:to find food;to interact in social

groups;to avoid predators;to reproduce.

A behaviour comes in response to a stimulus.

A stimulus is any change in the environment that affects the activity of an organism or what causes an animal to act in a certain way.

Stimuli may include:the sight of foodthe sound of a potential

predator the smell of a matedaily events such as

nightfall seasonal events such as

decreasing temperatures.

Innate behaviour Learned behaviour

independent of experienceindependent of

environmental conditionsinherited from parents -

genetic pre-dispositionpresent in all members of a

populationevolves through natural

selectionexample: blackcap

southern or western migration, nest building in birds, feeding in new-borns, fly larvae moving away from light

influenced by experienceinfluenced by environmental

conditionsnot inherited from parents –

no genetic pre-dispositionthe behaviour varies among

individuals of a populationspecific behaviour may not

be naturally selectedexample: dog learning to

walk on heel, human learning to juggle three balls, learning to ride a bike, ducklings following the first thing they see moving

Describe an experiments to investigate innate behaviour in invertebrates

place the invertebrates such as wood lice in a controlled environment

observe their behaviour to see which stimuli elicit a response

choose one stimulus that appears to change behaviour

ensure that other factors are controlled so that they do not have an effect on the response

use an appropriate method to measure the response

ensure sufficient numbers of repeats & animals to ensure reliability of the data collected

ensure that ethical standards are met i.e. animals should not be harmed

Kinesis and Taxis behaviourtaxis is movement

toward (positive) or away from (negative) a stimulus i.e. directional movement in response to stimulus

Examples: planaria worm moving towards food; euglena moving towards the source of light

Kinesis is more movement in unfavourable conditions and less movement in favourable conditions

the movement is not in any particular direction

Example: woodlice moving more in unfavourable dry conditions

Discuss how the process of learning can improve the chance of survival

animals learn to avoid dangerous situations such as predators or poisonous substances

animals learn how to hunt & (or) obtain food

animals learn to adapt to changing environmental conditions such as extreme weather

Example: birds learn to avoid the bad-tasting black and orange caterpillars of the cinnabar moth (by classical conditioning) and thus avoid possible poisoning hence increasing their chances of survival

Pavlov's experiments into conditioning of dogs

Outline Pavlov's experiments into conditioning of dogs Pavlov’s experiment involved

Classical Conditioningunconditioned stimulus -

smell & sight of food presented to the dogs

unconditioned response, salivation occurred

unconditioned stimulus - smell & sight of food accompanied by ringing of bell, the dogs salivated

conditioned stimulus of bell ringing given without unconditioned stimulus - sight of food

conditioned response, salivation occurs due to the bell ringing without the presence of food

Role of inheritance and learning in the development of birdsong in young birds

young birds learn birdsong from parents or other adults

when young birds are removed from parents, they are capable of singing own songs

thus, basic song template may be inherited, then modified by learning

learned birdsong is louder & richer in syllables