LEARNING BEHAVIOR

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Animal behavior Refers to the activities

animals perform during their lifetime, including locomotion, feeding, breeding, capture of prey, avoidance of predators, and social behavior. Animals send signals, respond to signals or stimuli, carry out maintenance behavior, mate choices, and interact with one another.

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Animal behavior relates to what

an animal does and why it does it. The types of behaviors exhibited by animals are rich and various. Some are genetically determined, or instinctive, while others are learned behaviors.

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Instinctive behaviors/Fixed Action Pattern:- Much of early research on animal behaviour was governed by the idea that animals, as opposed to humans, were largely guided by “instinctive” behaviour, where stimulus-response patterns are genetically pre-programmed and hard wired into the nervous system

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web making by spiders is an example of a genetically determined or instinctive behavior. There is little variation between individuals in how they construct the web and it is constructed similarly each time they do it. Ethologists (people who study behavior) call such a behavior a fixed action pattern. Fixed action patterns do not require learning or prior experience for their expression. They can, however, be very complex 5

EXAMPLE

Fixed Action Pattern

Egg Rolling in Graylag Goose

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EXAMPLE

Learning and memory are two sides of a coin. A number of surprising findings have lead researchers to believe that virtually everything we encounter is learned and is stored away in the brain

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Learning Behaviors

LEARNING Is the modification of behavior in response to specific experiences.

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Learning involves a change in behavior, often long lasting. It is not passed on to the next generation. Learning is characterized by persistent and measurable changes in behavior which are not associated with fatigue, altered motivation, or maturation. Some information or knowledge is acquired and is then used to alter the individual’s actions and responses. Learning as an adaptive behavior allows individuals to adapt to specific environment challenges. 9

According to Thorpe types of learning are given below. 1). Flexible. •Habituation (non associative learning)•Classical conditioning (associative learning) •Trial and error (associative learning) • Latent (associative learning) •Discrimination (associative learning) 2). Restricted.•Imprinting (associative learning) •Reasoning and insight (associative learning)

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Types of Learning

1. Habituation: It is the decrease in response to repeated or continuous stimulation or, it is the gradual fading of a response when a stimulus that proves to be safe, neutral or irrelevant is given repeatedly.

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Flexible learning

Habituation is the simplest form of learning. Habituation like phenomena is found in every group of animals from Weevil to Whales. By habituation animals learn to conserve energy and time by not responding to an irrelevant stimulus. If a neutral stimulus that has neither noxious nor beneficial consequences is repeatedly delivered to an organism, its response to the stimulus tends to decrease gradually and may eventually cease all together. By habituation animals learn, what not to do.

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Habituation is considered distinct from Fatigue and Sensory adaptation. Habituation has been reported to have correlation with a' change in Central Nervous System.

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A Spider is sitting in its web. The experimenter vibrates point on its web, resembling the signal set up when an insect is trapped. The spider runs out to investigate the source of the vibration, nothing is found and spider returns to its place in the, centre of the web. If this same neutral stimulus is given several times, the spider no longer rushes out to investigate. It remains in the centre of the web. It gets habituated to that stimulus

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Example 1

Example 2A Snail crawling across a sheet of glass retracts into its Shell when the glass is tapped. After a pause it emerges and continues moving. A second tap causes retraction again but it emerges quickly, frequent tapping on glass ultimately cause no response at all in snail and it will keep on moving. This is due to habituation.

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Example 3In the lab, Clark could easily get the Nereis to live in glass tubes. He found that mechanical stimuli like tapping on the tube or touching the head of the worm or even a sudden shadow passing over caused a rapid retraction into the tube, but the majority of worms emerged again within a minute. If these stimuli were repeated at 1 minute intervals the percentage of worms responding fell until none of them were retracting. Clark concluded that Nereis got habituated to the stimuli.

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Example 4Hydra has a long, slender body, and its still longer fine tentacles (Fig. 1d) sweep the water. A sudden increase In light, or a mechanical disturbance, can cause general contraction. In one experiment, hydra were mechanically touched on tentacles without a harm or benefit the number of hydra responding to this gentle touch declined indicating habituation.

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Dishabituation It has been experimentally proved that "the effect of repeated stimulation of one kind is cancelled by a new stimulus of another kind and this is called "Dishabituation". Example once hydra was habituated with soft mechanical touch, it responded to another kind of stimulus say a fish of light.

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2. Classical conditioning: The term conditioned reflex is inseparable from the names of Great Russian physiologists I.P. Pavlov (l941) and Sherrington (1942).

Reflexes :This term implies an automatic adjustment to maintain homeostasis without conscious effort.There are two types of reflexes• A simple reflex•A conditioned reflex

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A simple reflex is the simplest automatic functional unit of the nervous system capable of detecting change and cause a response to that change. Simple reflex are also known as inborn or unconditioned reflexes, fixed or inherited like the knee jerk, closing of eyes.

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Conditioned or acquired reflexes: (I)Are acquired in life, are not transmitted through genes.(II)They can be established or abolished.(III)They are always established upon some pre-existing unconditioned reflexes.These are flexible and steer animals through their changing environments by means of signs, sounds, smells. According to Pavlov, all kinds of habits arising from training, education and discipline are due to chain of conditioned reflexes.

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Conditioned Stimulus & Conditioned Response: Food stimulates salivary secretion This is an unconditioned reflex. Now, if a second stimulus like ringing of bell be applied just before giving of food, for some days, the bell sound will be able to elicit salivary reflex, even if no food is given. Such a stimulus is called conditioned stimulus and salivary secretion is conditioned response (CR).

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Example 1 Famous experiment of Pavlov with dog involved the salivary reflex. Dogs salivate when food is put into their mouths and Pavlov could measure the amount of saliva secreted, by inserting a fistula, through the cheek to the salivary duct, so that drops of saliva fell into a funnel and could be counted. A hungry dog was placed on a stand; dog was given meat powder that caused secretion of saliva. Pavlov rung a bell just prior to feeding, at first this stimulus caused no response,

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after repeating the same thing for 5-6 times, saliva began to drip from the fistula soon after the hearing of bell even before the meat powder arrived. Eventually, the saliva was produced after hearing the bell alone. The dog had learnt to respond to a new stimulus which was previously "neutral" and Pavlov' called this the Conditioned Stimulus (CS). The salivation response to CS is the Conditioned Response (CR). Prior to this learning, only the meat powder or Unconditioned Stimulus (UCS) was producing salivation or Unconditioned Response (UCR).

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Positive reinforcement The stimulation that follows with a reward is called positive reinforcement Negative reinforcement When stimulation is associated with punishment -it is termed as negative reinforcement. Pavlov had used positive reinforcement.

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Example In another experiment, an electric Shock (UCS) causes a dog to lift its paw (UCR), if a bell is rung (CS) just prior to UCS, the dog learns to raise its paw just after hearing the bell (CR). Here the CR is associated with punishment or negative reinforcement.

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Example2 Karl Von Frisch kept a dwarf Sheat fish that lived in a small tube at the bottom of its aquarium. Von Frisch fed the animals by holding the food (UCS) close to the tube and the fish quickly left its shelter (UCR) to eat it. One day he began to accompany feeding, with whistling, the fish had never responded to whistle before. But 5 days after, Von Frisch when whistled (CS) before feeding the fish came out of her tube to eat (CR), they got conditioned to whistling.

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Classical conditioning is clearly a natural phenomenon with real biological value. The animals learn to associate the presence of prey or predator with other normally occurring stimuli. The deer flee (UCR) at the sight of a tiger (UCS). When a tiger is moving towards a herd-the monkeys whoop, the birds make noises and these act as conditioned stimuli (CS) -and soon, just after hearing the alarm calls (CS) from monkey and birds the deer flee (UCR).

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Example 3

3. Trial and error or instrumental or operant learninga.This learning is called trial and error because in this animal tries again and again to achieve the goal, keeps eliminating errors and one day learns to perform it without any error.b.It is also called instrumental because animals were allowed to perform in an instrument.c. it is also called operant because animal operates upon surroundings.

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Conditioned learning is associated with unconditioned stimulus and response, whereas; trial and error has basic instincts and motivation (drive or urge) at the base. When animals are motivated by thirst, hunger, sex or fear they show restlessness, and exploratory or appetitive behavior during the course of which it performs spontaneously a variety of motor patterns viz-sniffing, walking and looking around. If one of these patterns is followed by reinforcement e.g. a hungry animal while exploring the surroundings receives food and if this association is repeated the animal learns to perform a pattern regularly to that particular situation.

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Example 1 An example will make it clear why this type of learning is called trial and error. In this experiment on learning Thorndike used, a problem box. This puzzle box, also called Thorndike box is a cage that can be opened from inside by depressing a lever. A cat is shut in, which tries hard to escape, it moves around restlessly, explores its surroundings, bangs its head and paw here and there to somehow open the box, after sometime, by chance it steps on the lever and the door opens.

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The second trial is the repetition of first, and the third, soon the cat concentrates more attention on the lever and eventually it moves swiftly across the box and presses the lever as soon as it is confined. The cat learns to eliminate behavior that led to no reward and increases the frequency of behavior which was rewarding. The first reward was obtained by pure chance.

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Experiment 2 Trial and error learning is not confined to animals with, well developed brains. It is also shown even by smaller creatures like earthworms. An earthworm is placed in the stem of T-shaped tube. If it turns left it is given the electric shock, if it turns right it is returned to its box without punishment. It is claimed by scientists that the worm learns by trial and error to associate turning left with punishment and eventually always turns right

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Example 3 A classical example of instrumental conditioning is that of a rat in Skinner box developed by Skinner (1904-1990), a prominent physiologist. When placed in a box, the rat begins explore it moves all about the box and, by accident, eventually presses a lever and is rewarded with a food pellet. Because food rewards are provided each time the rat presses the lever, the rat associate the reward with the behavior. Through repetition, the rat learns to press the lever right away to receive reward.

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In this type of learning, the animal is instrumental in providing its own reinforcement

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Experiment 4 An octopus is seen (in fig) leaving its shelter and advancing towards the crab at the other end of its tank. It faces two situations. 1.If it attacks the crab whose nearby a square is hanging, the octopus receives an electric shock. 2. In another situation, there was no square i.e. the electric plates was removed and octopus is allowed to attack the crab i.e. without getting an electric shock. After a few days, by trial and error, the octopus learns to attack when the crab is alone and does not attack the crab when an electric plate is hanging nearby.

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Prepared by:-

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AMAAN ALI