A2/A-level Biology - Animal Behaviour (1)

• The responses of an organism to its environment, which increase its chances of survival. 
• An organism must be able to detect changes in the environment, which form stimuli, then carry out an appropriate response through the operation of effectors.

• Animal responses which does not involve learning.
• It is an inherited response, similar in all members of the same species and is always performed in the same way in response to the same stimulus.

Advantages

• Quicker response time.
• Less need for parental care.
• Response is reliable in increasing their chance of survival.

Disadvantages

• Predators may be able to catch onto their behaviour and adapt, so that they can catch their prey more easily.
• Not adapted in response to changing environments.

• Often ‘escape’ behaviours – avoid predators.
• They are involuntary responses with identical responses to a given stimulus.
• E.g. woodlice will curl into a ball so that only the hard shell is exposed and can roll away if in danger.
• E.g. earthworms withdraw underground in response to vibrations on the ground.

• A taxis is a ‘directional’ orientation response, where the organism either moves towards or away from the stimulus.
• E.g. maggots are negatively phototaxic – move away from light.
• E.g. flies are positively chemotaxic – move towards chemicals (food).

• A kinesis is an orientation behaviour where the rate of movement (not direction) increases when the organism is in unfavourable conditions.
• E.g. woodlice avoid predation and drying out by living in damp, dark areas.
• If placed in dry/bright conditions, woodlice will move around rapidly and randomly until they move to more favourable conditions, when they will move more slowly or even stop moving.

• The linking together of a series of innate behaviours gives some complex behaviour patterns.
• E.g. the waggle dance used by honey bees to communicate the direction and distance of a food source to other worker bees.
• The angle between the waggle part of the dance and the vertical represents the angle between the sun and hence the direction of the flower field horizontally.
• The duration of the waggle part of the dance signifies the distance (1 second = 1km).

• A stimulus is required to initiate an instinctive behavioural response.
• Stimuli lead to releaser mechanisms within the brain, which in turn produce the response (FAP).
• E.g. in the courtship and mating of sticklebacks (fish), females will follow almost any small red object to the nest (in this case the male stickleback performing the zig zag dance), and once within the nest, neither the male nor any other red object need to be present.
• Any object touching near the base of her tail will cause her to release her eggs.

• Animal responses that change or adapt with experience.
• It is the greatest survival benefit to animals:
  (i) With a longer lifespan and so there is time to learn.
  (ii) With parental care of the young, which involves learning from the parents.
  (iii) Living with other members of the species in order to learn from them.
• The main advantage of learned behaviour over innate behaviour is that it is adapted in response to changing circumstances or environments.

When it comes to A2/A-level Biology, do you know the differences between innate behaviour and learned behaviour?

• Animals learn to ignore certain stimuli because repeated exposure to the stimulus results in neither reward nor punishment.
• For example, birds have learned to ignore scarecrows and humans living near rail or road links seep without constant awakening in response to noise stimuli.
• It avoids wasting energy in making escape responses to non-harmful stimuli.

• It involves young animals becoming associated with (imprinting on) another organism – usually the parent.
• Konrad Lorenz discovered that goslings follow the first moving thing they see on hatching and will only follow and learn from objects that look like the first object.
• Imprinting only occurs in a sensitive period (around 36 hours following hatching in birds).
• It is significant in helping the young to learn skills (flight in birds, knowing to seek out the appropriate type of organism for mating) from the parents.

• Classical conditioning is where animals can learn to relate a pair of events and respond to the first in anticipation of the second.
• This type learning is passive and involuntary.
• For example, Pavlov observed that when dogs were shown food, they salivated – normal reflex action.
• It is a response to an unconditioned stimulus.
• He rang a bell when he was about to give the dogs food and after a while he noticed that the dogs soon began to salivate on hearing the bell, even if they could not see the food.
• The ringing is known as a conditioned stimulus, which leads to a new reflex action called a conditioned response.

• Animals learn to associate action (the operant) with a reward (the reinforcer).
• This type of learning is active and to an extent voluntary.
• It is often referred to as trial and error learning.
• For example, B. F. Skinner carried out experiments with rats and pigeons, using a Skinner box.
• He showed that animals in the box would at first accidentally press a lever, which resulted in the reward of a food pellet.
• This reward led to increasing frequency of pressing the lever because the animals had learnt to associate the operation of pressing the lever with the reward of food.

• Animals explore new surroundings and retain information about their surroundings that may be essential to staying alive in the future.
• For example, young rabbits explore the surroundings of their burrows, learning the features of the environment.
• This knowledge can be life-saving if it helps the rabbit escape a predator in later life.

• Insight learning is regarded as the highest form of learning.
• It is based on the ability to think and reason in order to solve problems/deal with situations and then remember what was done to apply to future situations.
• For example, Wolfgang Köhler discovered chimpanzees presented with bananas hung out of reach and a set of boxes, stacked the boxes on top of each other to reach the bananas.
• Similar results occurred among gorillas, orang-utans and gibbons.

In part 2, you will know more about social behaviour.

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Drafted by Bonnie (Biology)