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OCR A2 UNIT F215 ANIMAL BEHAVIOUR Specification Content: Explain the advantages to organisms of innate behaviour Describe escape reflexes, taxes and kineses as examples of genetically determined innate behaviours Explain the meaning of the term learned behaviour Describe habituation, imprinting, classical and operant conditioning, latent and insight learning as examples of learned behaviours Describe using one example, the advantages of social behaviour in primates Discuss how the links between a range of human behaviours and the dopamine receptor DRD4 may contribute to the understanding of human behaviour Definition of Animal Behaviour: The responses of an animal to its environment that increase its chances of survival TYPES OF ANIMAL BEHAVIOUR INNATE BEHAVIOUR LEARNED BEHAVIOUR Escape reflexes Habituation Taxes imprinting Kineses Classical conditioning Operant conditioning Latent learning Insight learning 1 Features of Innate/Instinctive Behaviour Genetically inherited response to a stimulus Stereotypical. This means that the response is the same in all members of the species Automatic. These responses require no previous experience and are not learned Rigid and inflexible response. This means that the response is the same in all members of the species Innate behaviour patterns only survive if they offer an advantage to the species (natural selection) Which animals show innate behaviour? All animals including humans show innate behaviour. It is very important in invertebrates Advantages of Innate Behaviour for Survival Innate responses are rapid and automatic They only require a simple nervous system They are important in species such as invertebrates that have a short lifespan – there is insufficient time for them to learn survival skills They are also important in species with no parental care and those with solitary lifestyles Innate behavioural patterns enable some animals to: Escape predators Locate and stay in a suitable habitat Find food or a mate Some Examples of Innate Behaviour – three types as tabulated below Escape Reflexes Examples of Escape Reflexes Stimulus Response Advantage of Response Withdrawal reflex from a hot object (humans) Touching a hot object Prevents serious burn injury to the person Escape reflex of earthworms Soil vibrations such as an animal walking on or digging the soil Rapid and automatic removal of the body part from the hot object Earthworm moves in the soil, further away from the vibrations To avoid predation Taxes (singular = taxis) – taxes are directional orientation responses 2 Examples of Taxes Directional Stimulus Response Advantage of Response Negative phototaxis of maggots Light Maggots move in the direction away from light Positive chemotaxis of a nematode worm (these worms have chemoreceptors in their lips) The chemicals of food The nematodes move in the direction towards the chemicals To keep the animal in a suitable environment (the dark) in order to avoid predation To find food Kineses (singular = kinesis) – kineses are non-directional orientation responses Example of Kinesis Non-directional Stimuli Response Advantage of Response Response of woodlice to light or dry environment Light or dry conditions Woodlice move rapidly but randomly seeking dark and damp conditions. Their movement is non-directional. The rate of these movements depends upon the intensity of the stimuli To avoid predation and prevent drying out (woodlice breathe by gills that need a moist gas exchange surface) More Complex Innate Behaviours – the waggle dance of the worker honey bees 3 Worker honey bees carry out a waggle dance when they return to the bee hive, after finding a nectar food source. The dance is a communication to other worker honey bees of the location of the food. The angle of the waggle part of the dance to the vertical represents the direction of the food source. The duration of the waggle part of the dance indicates the distance of the food source. (see page 241 in A2 textbook) Examination Question on Behaviour Breeders of Colourpoint Persian cats are advised to be present at the birth of the kittens. In this breed, the mother cat may not perform essential maternal behaviour such as licking the newborn kitten to free it from the amniotic sac. Wildcat mothers even when they are first-time mothers, perform this behaviour naturally 1. State the type of behaviour shown by these wild-cat mothers Type of behaviour…………………………………………………….. Characteristic …………………………………………………………. 2. Over time, the frequency of domestic cat mothers who perform essential maternal behaviour, such as licking the newborn kitten, has decreased Suggest and explain a reason for this change in frequency over time …………………………………………………………………………………… …………………………………………………………………………………… …………………………………………………………………………………… …………………………………………………………………………………… ……………………………………………………………………………………. Features of Learned Behaviour Animal behaviour that is learnt and changed by past experience. It is learnt from an animal’s parents and by watching others 4 Variable behaviour. There is much variation between different members of the same species or in one animal at different times as the behaviour is modified with experience Learned behaviour is memorised and reinforced with practice General Advantages of Learned Behaviour Learned behaviour enables an animal to adapt to changes in the environment Types of Learned Behaviours 1. Habituation If a stimulus is repeated and is harmless, the animal learns to ignore it. . It is the simplest form of learning Examples of Habituation: Opening an umbrella in front of a young calf will cause it to flinch and move away. After repeated stimulation, the response lessens and eventually stops – the calf then ignores the stimulus Birds learn to ignore scarecrows Humans screen out non-dangerous stimuli such as wind and waves Humans living next to a busy road will have difficulty sleeping because of the noisy traffic. This response lessens over time as the humans learn to sleep without constant disturbance Advantage of Habituation To conserve energy - habituation prevents an animal from wasting energy by not escaping from nonharmful stimuli 2. Imprinting During a sensitive period (or receptive period) in an animals life, the animal learns the features of its parent and thereafter associates with the parent. The sensitive period is usually after birth or hatching. Imprinting is a behaviour shown by human babies and young birds Konrad Lorenz showed that goslings follow the first moving thing that they see on hatching. Thereafter, they will only follow and learn from things that look just like the first thing they experienced. 5 Advantage of Imprinting Access care - imprinting enables young animals to be looked after by their parents 3. Classical Conditioning This is where animals can learn to relate a pair of events and respond to the first in anticipation of the second. In classical conditioning there are two stimuli Classical conditioning was described by Ivan Pavlov who was investigating salivation in dogs. He rang a bell when providing food to the dogs. The dogs salivated at the sight and smell of the food. They soon associated the bell ringing with the food, and salivated even when the bell rung and no food was given. A summary of the stimuli and responses is tabulated below. Stimulus Sight or smell of food - the unconditioned stimulus Response Salivation – the production of saliva by the salivary glands - the unconditioned response Sound of bell ringing –the conditioned stimulus Salivation - the conditioned response 6 Advantage of Classical Conditioning Since the example of Pavlov’s dogs is experimental, an advantage cannot be given Another Example of Classical Conditioning The training of guide dogs for the blind involves classical conditioning. When a guide dog is taking his blind companion across a road at a pedestrian crossing, the dog is trained to wait on the path until the sound signal indicates that the traffic has stopped and it is safe to cross. 7 The advantage of this conditioning is that the dog can safely guide his blind companion across the road 4. Operant Conditioning This is where an animal learns to carry out a response so as to receive a reward or to avoid an unpleasant experience, such as a mild electric shock. This conditioning was studied by B.F.Skinner who devised Skinner boxes in which rats or pigeons move around. The animal in the box accidently (at first) presses a lever and receives some food. The animals learnt to associate an operation (hence operant conditioning) with a reward. If pressing the lever induced an electric shock – a punishment – the animal again learnt this association. The rewards/punishments are often referred to as re-inforcers. Operant conditioning is also described as trial and error learning or associative learning. The repeated success of the operation brings about the reinforcement of the association between the operation and the response – there is reinforcement in operant conditioning Other examples of operant conditioning The training of dogs and other animals (including humans) is based on a reward for successful outcome of the training process. A dog can be trained to beg by receiving a food reward when this behaviour is carried out as required by the dog owner. As the dog learns the association of a reward with the begging operation, its begging behaviour increases Advantage of operant conditioning Animals learn how to access food or some other reward or how to avoid an unpleasant experience Experimental Controls Skinner would have used controls in his experiments to show that the animal learned that carrying out an operation resulted in a reward In the case of the rat/pigeon experiments, he would have controlled the experimental variables: used the same experimental box used an animal of the same species, age and gender kept all experimental conditions the same eg the same environmental temperature animals fasted before the trials to ensure that they are hungry The difference would be that carrying out the operation (pressing the lever) would not result in a reward. 8 For the control there would be no pattern in the times of pressing the lever. This operation would occur randomly 5. Latent Learning Animals explore and learn details of their surroundings that could be useful in the future. Young rabbits explore the environment around their burrows. Advantage to the rabbits: At some future time, this information will be vital for the rabbits to escape predators 6. Insight Learning Insight learning is the highest form of learning and is based on the ability to think and reason in order to solve problems. Once solved, the solution is remembered. Animals integrate past experiences to show a new piece of behaviour. Kohler studied chimpanzees in captivity in the Canary Islands. He gave them boxes to play with. They used them to reach bananas. When the bananas were hung a long way above them, they stacked the boxes to reach them. Latent learning probably played a part in this behaviour. The chimpanzees played with the boxes before the bananas were offered, and had learned the stacking technique previously. Advantage of insight learning to the chimpanzees: Enables the chimpanzees to access food Social Behaviour in Primates Primates are mammals and include apes, monkeys and lemurs Most primates live in family groups where the young remain until they reach sexual maturity (12 years in chimpanzees) The family group shows a hierarchy where individuals have a place in the order of importance within the group. This leads to social control which protects all group members. 9 Social Organisation of Gorillas Mountain gorillas live in stable groups called a troop of around 10 individuals One mature male is at the top of the hierarchy – the Silverback. He protects several adult females in the troop and their offspring The Silverback mates with all the adult females and leads the troop in search of food As younger males mature they leave the troop and seek other females. Younger females either remain or join another group Social Behaviour of Gorillas Grooming is an important social activity. Each individual picks out the parasites from the fur of another, reducing disease and parasite infection. This reinforces the bonds between individuals There is an extensive period of care for gorilla offspring. Each mother suckles her offspring and remains in very close contact with her young for up to a year. She protects the young gorilla as it learns the social skills to live independently. Juvenile gorillas from about 2 years play together and imitate adult behaviour The Silverback is also important in the development of its offspring from 3 to 6 years as it protects them from older males in the troop and teaches them new skills such as the use of tools Gorillas communicate through calls, displays and grunts. These communications are used:: 1. To threaten predators 2. To warn other troop members of danger 3. In play fighting as juveniles learn how to behave as adults Facial expressions are also used for communication and recognition of other troop members The Advantages of Social Behaviour in Primates The maternal care and group protection of offspring increases the survival rate of the young Learned behaviour increases the survival rate. The young learn through observation and play with other troop members The group has knowledge of and protects food sources Members of the group work together to detect and frighten off predators 10