Animal Behaviour
- 1. Animal Behaviour Dr. Sonia Bajaj Assistant Professor Department of Zoology Shri Shankaracharya Mahavidyalaya, Junwani ,Bhilai
- 2. Ethology • The study of animal behavior with special aspect to the natural environment and physiological, evolutionary aspects. • “St. Hillarie” choose the term Ethnology in late 18th century refer to study of animal as living beings in their natural environment. • Language: Human using communicate with each other by using structural language. Behaviors • Animal behavior includes all the ways animals interact with other organisms and the physical environment. • Behavior can also be defined as a change in the activity of an organism in response to a stimulus, an external or internal cue or combo of cues. • Some behaviors are innate, or genetically hardwired, while others are learned, or developed through experience. • Behaviors have both an innate component and a learned component. • Behavior is shaped by natural selection. • Many behaviors directly increase an organism's fitness, that is, they help it survive and reproduce.
- 3. Patterns of Behaviour • Behaviour is an external act of an animal but it depends on its anatomy and physiology as well. • In response to the external and internal stimuli. • The different forms of the action or behaviour of animals is called the patterns of behaviour. • It involves the programming of behaviour in the central nervous system and thereafter it release by the specific stimulus. • The behavioral pattern once originated continues to act independently. 1. Feeding Behaviour- • All the animals need food for obtaining energy to carry out various life activities. • Their feeding behaviour includes searching, catching and intake of food along with the termination of the process. • The principle of feeding includes intake of food while not being caught as food by another. • The behavioural adaptations for feeding involves detection of the nature of their diet and predators or by ecology. • The food obtaining methods of different animal species show diversity but there are certain broad patterns for feeding. The feeding adaptation are as follows- 1. Food selectivity 2. Duration of food intake 3. Feeding tools and techniques
- 4. (1)Food selectivity: -All animals are selective in choosing their food in their natural habitat. Examples- cattle's show feeding selectivity for only certain plant species and for selective parts of an individual plant. & Birds are selective in seed eating. They prefer the seeds according to their nutritional value as well as the size and structure of the birds bill. The best example is that of Galapagos finches. (2) Duration of food intake: -Animals show specific peculiarity in feeding by deciding the amount and quality of food as well as the number of times they feed. Examples-Stickle-back fish takes its meals for about three to four times in the form of worms. If the meals are avoided for atleast one time, its feeding behaviour changes, and when after sometime, the food is supplied, the rate of intake increases and gradually decreases when the stomach nears to full. (3) Feeding tools and techniques: -Natural selection has resulted in developing certain techniques in animals so as to capture their required food, which minimizes the net rate of energy. Examples-Hydra have tentacles armed with stinging cells called nematoblasts or nematocysts. When the food comes in vicinity, the nematocysts get discharged, inject the toxic fluid in the body of the prey, paralyse it, and then the tentacles capture the prey bringing it to mouth for imbibing.
- 5. 2. Social Behaviour- • The animals usually live in groups or colonies, in which the members are interdependent for various activities. • Each individual is assigned to do specific work. • This work distribution characteristic between the members of the group is called division of labour, and their organization is called social organization. • Different members in a group play different roles according to certain factors such as their caste, age, sex or other relationships. This behaviour is called social behaviour. Main purposes for social behaviour: (i) To sort out the food problems. (ii) For protection against predators. (iii) Avoidance of entry of the intruder by forming area or habitat limitations. (iv) For breeding purposes. (i) Social behaviour in vertebrates: Examples – (1)In animals like frogs and toads, the members of sexes come together temporarily for mating, lay fertilized egg and then depart, leaving the eggs to develop on their own. (2) In many species like fishes and birds either one or both parents stay to look after their young. When this happens, a social group results. In cichlid fishes such as Tilapia, the mother shows parental care by carrying the fertilized eggs and newly hatched ones in her mouth.
- 6. Social behaviour in invertebrates: Example- In bees: Three castes of honey bees are: (a) Drone, (b) Worker, (c) Queen. The queen of honey-bees is unable to perform any duties except mating and egg- laying. It is the fertile female of the colony. It possesses ovi-position cum-sting which helps in egg-laying. The drones are haploid males which are able to fertilize the queen. The drones are larger and noisy and consist of the well-developed reproductive organs. Sting and wax-gland are absent. The number of drones in a colony reaches up to 200 to 300. For food, they are dependent on workers. The workers are diploid sterile females and smallest members of the colony. They possess special structure to carry out various functions like powerful sting and wings. The functions carried down by the are: • Outdoor duties like collection of nectar, pollen etc. • Defend the colony. • Attend and take care of queen and larvae. • Produce wax for hive formation. • Repair and clean the hives. • Fan by wings to circulate cool air in the hive.
- 7. 3. Predatory Behaviour in Social Carnivores • The behaviour of devouring or killing of other animals by a particular species is called predatory behaviour. Example- Lions hunt in groups, but their cooperation behaviour is not true in its sense. The females actively hunt their preys by encircling the herd of preys, but males drive the females from the kill. Cubs are the last to get food. George Schaller believed that the populations of lion are regulated directly by the food supply through starvation of cubs. Also that during the excess scarcity of food, some males move into the group as strangers and may kill the cubs. 4. Anti-predator Behaviour Most of the animal species are in potential danger of being eaten by another . But such animals have evolved ways of diminishing this danger, so that the species survival and reproduction is maintained. Such ways and mechanisms adapted in avoidance of predation is called anti-predator behaviour. Example- 1.Camouflage- Camouflage is a method of being avoided to be seen. Usually predators hunt by eye-sight and the animal which is well-camouflaged able to defend itself. 2. Freezing and bluff- occurs in some animals such as American opossum, phyllium and stick- insects which lie motionless as if dead, and can thus avoid the attack of predators. Some tropical blue butterflies have false eyes and false antennae which divert attacks to the wrong end of the animal.
- 8. 5. Aggression or Agonistic Behaviour- • It is a complex behaviour and also includes predatory behaviour. • It is actually agonistic In simple words, the behaviour including fights, disputes and conflicts is aggression. • behaviour patterns includes threat, quarrel, chases, physical combat etc. • The agonistic behaviour is the response to the competitions for some resource. Types of aggressive behaviour: (a) Territorial aggression: • The area or the habitat occupied by an animal or the species, where it spends most of its lifetime, is called territory. • It consists of the sources of basic necessities like food, water, nest and sleeping sites as well as the reproductive places. Examples: Robin, Blue tit defends its territory. To the Blue tit male, his territory represents the food that he and his mate will need to rear their youngs successfully. They defend their territory from the members of other species like gibbons, monkeys and antelopes. (b) Sexual aggression: In animals like ducks and geese, sexual aggression is witnessed where they use 'triumph ceremonies' to strengthen the pair bond. The male goes to attack an opponent and after defeating it returns to his female. There after it gets engaged in a mutual 'cackling' ceremony with her.
- 9. 6.Reproductive Behaviour- • Reproduction is one of the most important biological phenomenon. • Any species is able to maintain the continuity of its race and its survival. • This is an unique ability of an animal which is contributed to the gene pool of the next generation. • This phenomenon involves a set of responses which together form the behavioural patterns known as 'reproductive behaviour'. • The reproductive behaviour, in general, include the mating between the participants of opposite sexes or strains and rearing of offsprings. • Courtship duration can vary from a few minutes to few hours. • The individuals involved in the reproduction process, usually belong to the appropriate sex, species and conditions. Factors for reproductive behaviour: 1. Right mating member 2. Breeding time or season 3. Breeding system 4. Struggle of males and females
- 10. 7. Parental Behaviour • The caring and looking after their youngs by human parents as well as that of most of the animals is called 'parental behaviour'. • sea urchins and certain fish species lay clouds of eggs but only a limited number of them will survive to attain adulthood. • The parental behaviour is best exhibited in the form of 'parental care'. • The ways of parental care in different animals are as follows: • The youngs within the eggs are supplied with yolk in the form of food. • The young fish even after hatching still carry a yolk sac around them. • The female digger wasp paralyses the grasshopper and drops it in the burrow having eggs. When the young ones hatch out, they get fresh food. • Mammals like mice and human beings carry their young ones in their wombs until they have reached a stage when they ought to be able to feed themselves. • Cichlid fishes such as haplochromis have their females carrying the fertilized eggs and later the young fishes in her mouth • After birth or hatching, the parents of many species continue to take care of their young ones for days, months or even years by providing them food, shelter and protecting them from predators. • Mammalian mothers feed their young ones with their milk, and they are lactating mothers. • Kangaroos of Australia carry their infants in the special pouches in their body called ‘marsupium’.
- 11. TYPES OF BEHAVIORS A. Stereotyped / Innate Behavior - A behavior with which the organism is born. B. Learned / Instinctive Behavior -A change in behavior due to experience. A. Stereotyped Behavior / Innate Behavior • When an individual repeats the same pattern of behaviour again and again. • It is also called innate or inborn or inherent behaviour. • Examples - fish swimming and geese migrating. Characteristics • They are complex in origin and are predictable. • They are initially stimulus dependent. • They do not results as a consequence of experience. Modes of stereotyped behavioral pattern: • 1. Spatial orientation (Kinesis & Taxis) • 2. Reflexes • 3. Instincts • 4. Motivation
- 12. B. Learned / Instinctive Behavior-Learned behavior is one that is not innate, instinctive or “canalized” but rather is acquired through practice or a specific experience with an external event. Example- Playing an instrument, playing sports, TYPES OF LEARNED BEHAVIOR 1. Habituation 2. Imprinting 3. Conditioning Classical conditioning • A process in which an animal learns to associate a previously neutral stimulus with a behavior once triggered by a different stimulus . • Pavlov’s Dog Habituation • Forming a habit • Learning to get used to something after being exposed to it for a while Example: The habit of seeing a scarecrow in the exact same place in the garden every day causes birds to get used to, and basically ignore, the stimulus. Imprinting • The process by which young animals attach to those who are present at their first sight. • It assures that young stay closed to their mother for protection and as a source of food.
- 13. INNATE BEHAVIOR LEARNED BEHAVIOR Innate Behaviors Learned Behaviors Inborn Based on Experience Not modified by the individual Generally uniform Low variation in population Modified by the individual by trial and error High variation in population Unaffected by the environment Highly affected by the environment Examples: • Suckling in newborns • Migration • Hunting instincts Examples: • Language acquisition • Social Skills • Domesticated behavior in pets • Trained dolphins
- 14. Types of innate behaviour • Irratibity • Tropisam • Nasties • Taxes • Kinesisi • Reflex action • Instinct • Motivation Irritability - Irritability is an excessive response to stimuli. Conditions • Irritability can occur in people experiencing any of a variety of conditions, including: -Anxiety, Alcoholism ,Fever Example- • Protozoans lack nervosa system but protoplasm is capable of receiving the stimuli. • They can distinguished between edible and non edible particles.
- 15. Tropism : (from Greek trope, "a turning") • It is a biological phenomenon, indicating growth or turning movement of a biological organism, usually a plant, in response to an environmental stimulus. or • Involuntary orientation by an organism or one of its parts that involves turning or curving by movement or by differential growth and is a positive or negative response to a source of stimulation. • In tropisms, this response is dependent on the direction of the stimulus. • Tropisms are typically associated with plants. Types of tropism • Chemotropism-movement or growth in response to chemicals . • Geotropism (or gravitropism)- movement or growth in response to gravity. • Heliotropism- movement or growth in response to sunlight. • Sonotropism- movement or growth in response to sound. • Hydrotropism- movement or growth in response to water. • Phototropism- movement or growth in response to lights or colors of light (Example- The sunflower). • Thermotropism- movement or growth in response to temperature. • Electrotropism- movement or growth in response to an electric field. • Thigmotropism- movement or growth in response to touch or contact.
- 16. Nasties • These are non directional responses to stimuli (e.g. temperature, humidity, light irradiance), and are usually associated with plants. • The movement can be due to changes in turgor or changes in growth. • Nastic movements differ from tropic movements in that the direction of tropic responses depends on the direction of the stimulus, whereas the direction of nastic movements is independent of the stimulus position. • Types of nasties • Epinasty: Downward-bending from growth at the top. Example- Bending down of a heavy flower. • Photonasty: Response to light. • Nyctinasty: Movements at night or in the dark. • Chemonasty: Response to chemicals or nutrients . • Hydronasty: Response to water. • Thermonasty: Response to temperature. • Geonasty/gravinasty: Response to gravity. • Thigmonasty/seismonasty/haptonasty: Response to contact. Mimosa pudica plant
- 17. Taxis • A taxis from ancient Greek meaning arrangement. • It is an innate behavioral response by an organism to a directional stimulus or gradient of stimulus intensity. • A taxis differs from a tropism (turning response, often growth towards or away from a stimulus) in that the organism has motility and demonstrates guided movement towards or away from the stimulus source. Examples -Euglena have an EYESPOT: a photoreceptive organelle that allows the cells to sense Light direction and intensity and respond to it by swimming either towards the light (positive phototaxis) or away from the light (negative phototaxis).
- 18. Distinguishing features of taxis – The important distinguishing features of taxis are as follows: (i) It is a stereotyped pattern of behaviour and species characteristic. (ii) It is a fixed action. (iii) It involves spatial orientation. (iv) The whole body is involved in the orientation. (v) Two types of reactions are involved in it avoiding reactions and trial and error reactions. (vi) The external stimulus continuously guide the direction of movement of the animal. (vii) The movement involved in orientation is directly proportional to the stimulus strength. (viii) Two types of responses are included positive and negative responses. (ix) It involves locomotor responses. (x) It is an adaptive behavior by which an animal is able to avoid the extreme conditions and get itself adapted to be in the favourable conditions.
- 19. Types of Taxis 1. Aerotaxis- Aerotaxis is the response of an organism to variation in oxygen concentration, and is mainly found in aerobic bacteria. 2. Chemotaxis-Composed of two words "chemo + taxis". • Chemo means a "chemical substance" is a form of matter that has constant chemical composition and characteristic properties. • Taxis means "arrangement" is the movement of an organism in response to a stimulus such as light or the presence of food. • Chemotaxis is the movement of an organism/bacteria in response to a chemical stimulus i.e., move away or towards substances that are present in the environment through a non-random process. Example-E. coil • This movement is often directed either • Positive chemotaxis - movement towards attractants (nutrients) • Negative chemotaxis- movement away from the repellents (toxin).
- 20. 3. Phototaxis -Composed of two words photo + taxis". Photo meaning “light” Taxis meaning the movement of an organism in response to an external stimulus. Phototaxis is the locomotory movement of living organisms directionally towards the source of light or away from the source of light. Positive Phototaxis - response to towards the source of light. Negative Phototaxis –response to away from the source of light. Example- Rhosdospirillum & Euglena grows and moves towards (positive phototaxis) or away (negative phototaxis) from light depending on their needs. 4. Thermotaxis -Thermotaxis is a migration along a gradient of temperature. Example- a. Euglena is active when the optimum temperature for it is between 25°C to 30°C. b. Paramecium behave normally and is active when the optimum temperature range is 24°C to 28°C. c. Amoeba shows unusual behaviour. It responds negatively to both low and high temperatures. The optimum temperature ranges between 20°C and 25°C. It ceases all activities at temperatures above 35°C.
- 21. 5. Phonotaxis -Phonotaxis is the movement of an organism in response to sound. 6. Gravitaxis -Gravitaxis is a response to the attraction due to gravity. The planktonic larvae of the king crab (Lithodes aequispinus) use a combination of positive phototaxis (movement towards the light) and negative gravitaxis (upward movement) Both positive and negative gravitaxes are found in a variety of protozoans. 7. Magnetotaxis- Magnetotaxis is the ability to sense a magnetic field and coordinate movement in response. The term is commonly applied to bacteria that contain magnets and are physically rotated by the force of the Earth's magnetic field. In this case, the "behavior" has nothing to do with sensation, and the bacteria are more accurately described as "magnetic bacteria. 8. Galvanotaxis / electrotaxis- It is directional movement of motile cells in response to an electric field. It also is suggested that such a movement may contribute to directional growth of cells and tissues during development and regeneration. 9. Rheotaxis –It is a response to a current in a fluid. Positive rheotaxis is shown by fish turning to face against the current. In a flowing stream, this behavior leads them to hold their position in a stream rather than being swept downstream. Some fish will exhibit negative rheotaxis where they will avoid currents. 10. Thigmotaxis -Thigmotaxis is the response of an organism to physical contact, or to the proximity of a physical discontinuity in the environment (ex. rats preferring to swim near the edge of a water maze).
- 22. 11. Klinotaxis -Klinotaxis occur in organisms with receptor cells but no paired receptor organs. The cells for reception are located all over the body, particularly towards the anterior side. The organisms detect the stimuli by turning their head sideways and compare the intensity. When the intensity of stimuli is balanced equally from all sides then the organisms move in a straight line. Examples: movement of larva of blowfly and butterfly. 12. Tropotaxis -Tropotaxis are displayed by organisms with paired receptor cells. When the stimuli coming from a source is balanced equally the organisms show movement. In this animals are capable of showing sideways movement unlike klinotaxis where the organisms show movement in a straight line. Example: movement of Greyling butterfly. 13. Telefaxes -Teleotaxis require paired receptors. The movement occurs along the direction where the intensity of the stimuli is stronger. Example: when bees move from their hive for food they balance the stimuli from the sun as well as flower but reside on the flower whose intensity is higher for them.
- 23. Kinesis • Animals have specific needs (e.g. food, humidity). • No information about the location of resource. • Undirected search. • Kinesis - random movement due to the presence of a stimulus. The rate of activity is determined by the intensity of the stimulus - not the direction. Klinokinesis = stimulus intensity determines rate of turning • Kinesis is an animals non-directional response to a stimulus, for example humidity. The animal does not move toward or away the stimulus but moves at either a slow or fast rate depending on its "comfort zone." In this case a fast movement (non random) means that the animal is searching for its comfort zone but a slow movement indicates that it has found it. Types of kineses 1. Klinokinesis: (Greek) – to make bend • A form of kinesis in which the frequency or rate of turning is proportional to stimulus intensity. • Klinokinesis is well demonstrated by the movements of the wood louse. • Klinokinesis = stimulus intensity determines rate of turning • Ex. lice turn less often at 30° - straight line. Human skin temp is about 35°. lice more likely to linger at 35°. Example-When the wood lice are placed in humid air, they move at first, but any activity they exhibited soon ceases and they become quiet. Wood lice placed in a container with dry air at one end and humid air at the other gradually congregate at the humid end. This transfer is achieved through what appear to be random rather than directed movements.
- 24. 2. Orthokinesis Orthos (Greek) = straight • In orthokinesis, the intensity of the stimulus governs the speed of movement. • It is the frequency of change from rest to movement. • Examples of orthokinesis are seen in lampreys, which are more active in high intensities of light. • cockroaches, which are more active in low intensities. • Flatworms and many kinds of fly larvae, among other invertebrates, exhibit orthokinesis.
- 25. Reflexes • Reflex or reflex action is the sudden, automatic or involuntary act of behaviour of an animal or human. • Reflex a specific, short-lived response to some kind of stimulation. • Responses are evoked as a result of the body activities to environmental changes, both internal and external. • The reflexes occur are immediate and rapid. • The act involved in the production of a reflex is called reflex action. • It is defined as an automatic response mediated through the nervous system and elicited by a sensory stimulus. The brain, actually, is not immediately involved. Basis of Reflex Action- The various units consisting of nerve cells and synapses are organized to form an effective system of communication. The nerve cells must receive impulses from receptors and in turn pass them on to effectors. This is the basis of reflex action. Distinguishing Features of reflex 1. Reflexes are automatic, rapid, short-lived, involuntary and stereotyped behavioral reaction. 2. Reflexes involve the movement of a part of the animal body. 3. Reflexes are not continuously guided by the stimulus. 4. They exist in an individual from birth and hence are innate. 5. They may also be learned depending on the past experiences, and hence can be declared as acquired ones. 6. Reflexes result due to the complicated neural mechanisms. 7. They form the most effective system of communication. 8. Reflexes depend upon the strength of the stimulus.
- 26. Types and classification of reflex Types- 1. Tonic reflexes: • Reflexes are slow ones and the responses are long-lasting. • Tonic reflexes maintain the posture and equilibrium of the animal as they are related with the toning of muscles. 2. Phasic reflexes: • Reflexes are fast and the responses involved are short-lived. • These are observed in the flexure responses of the animal body. Classification- 1. Exteroreceptor reflex: It is due to stimulation of receptor on the outer surface of body. 2. Enteroreceptor reflex: It is due to stimulation of receptors of the internal organs. 3. Proprioreceptor reflex: It is due to stimulation of receptors on the skeletal muscle joint and tendons. 4. Spinal or cranial reflex: It depends on the part of central nervous system involved. 5. Conditional reflexes: These are those habits or voluntary activities which in due course of time become reflex actions, e.g., cycling, salivation, driving, swimming, etc. 6. Unconditional reflexes: These are due to receptors involved and stimulus. These are normal reflex actions of the body, e.g., contraction of the pupil of the eye in bright light, closure eyelids, etc.
- 27. Examples of simple reflexes : (a) If the stimulus is applied below the knee cap on the patella tendon, by hitting it lightly, the knee jerks. This is called the 'knee-jerk reflex'. (b) If the finger is accidently pricked by a needle, the hand is suddenly withdrawn. This is 'finger-prick reflex'. Physiology of 'knee-jerk reflex' and 'finger-prick reflex': The 'knee-jerk' and 'finger-prick', the sensation of pain is perceived by several pain receptors in the skin. These send impulses by the dorsal sensory roots to the spinal cord. The sensory neuron synapses with an interneuron in the grey matter. The impulses from here are finally transmitted by the ventral motor neuron to the muscles of the effector organs. The muscles contract in response resulting in the withdrawal of the finger or leg. It in the fraction of a second. When the brain is intact, a nerve fibre from the spinal cord carries the stimulus sensation to the pain centre of the brain. It is only then that one can feel the pain. Before this realization of pain, the leg or hand (knee or finger) has already been withdrawn as here the nervous response is involuntary and occurs before one is aware of the stimulus. This is called the reflex action. c) A sudden coughing is suffered by the individual if during eating or drinking, the undesirable component is inhaled. The sudden response in the form of cough is called 'cough- reflex'. (d) The 'corneal reflex' is the response elicited by the confrontation of any object which suddenly approaches the eye. The response is in the form of sudden and quick closing of an eyelid.
- 28. Vertebrate reflex arc- The vertebrate reflex arc involves the spinal cord and the spinal nerves. It is also known as 'spinal reflex response'. Structure of the Vertebrate Reflex Arc – • Each spinal nerve is attached to the spinal cord by separate dorsal and ventral roots. The dorsal roots contain the sensory nerve fibres and the ventral roots contain motor nerve fibres. • The cell bodies of the sensory neurons are present in the swelling of the dorsal root, the dorsal root ganglion. • The intermediate nerve cells and the cell bodies of motor nerve cells are located in they matter of the cord. The axons of the motor neurons run out into the ventral roots. • In the vertebrate nervous system, there are numerous reflex arcs. Each arc correspond to the series of spinal nerves. These reflex arcs are interconnected by longitudinal neurons located in the white matter of the cord.
- 29. Reflex path 1. Stimulation is perceived by pain receptors in the skin. 2. Impulses are triggered or initiated in the sensory neuron of the concerned part of the body. 3. Impulses enter the spinal cord via dorsal roots. 4. The impulses so received traverse the intermediate neurons in the grey matter. 5. The impulses leave the spinal cord via the motor neurons in the ventral roots. 6. On reaching the flexor muscles or the effectors, the impulses lead to the contraction of muscles and hence withdrawal of the body part. Control of reflex 1. Central control- The control at central level involves the sending off of precise instructions by the brain which are received and obeyed by the effectors like muscles or the concerned organs. Movement of eye-ball and swallowing movements in mammals involve the coordination of muscles. 2. Peripheral control- The sensory and muscular systems help in the control at peripheral level. Such reflex control plays an important role in the movement of limbs when subjected to loads.
- 30. Reflex centre- The activity of a particular group of effectors is controlled by a group of neurons in the spinal cord or brain. This group of neuron is known as the reflex centre. example- breathing, heart rate, vomiting, coughing, swallowing, etc. are present in the medulla oblongata of brain which controls the impulses conducted to the concerned effectors. Models of Reflexes The control mechanism of reflexes was illustrated with the help of two models described by Manning and Dawkins (1998). These two models are as follows: 1. Open-loop model- In open-loop model, the interaction of input coming to behavioral system takes place with that of the output received. The output is compared to the response evoked. The output howsoever disturbed, does not affect the behavioral system. The output and input are not closely associated so as to affect each other to a great extent. 2. Closed-loop model- The closed-loop model describing the control mechanism, the input and output are interacted to each other. Any disturbance to output affects the input and thus the complete behavioral system is influenced. The closed-loop model operates when the responses are slow. Fig- A-Open-loop model B-Closed-loop model
- 31. Instincts • Instinct is the kind of behaviour which is natural, and it is not acquired through previous learning experience. • This behaviour is present in the animal since birth. • Due to a specific stimulus this kind of behaviour is in a fixed activity pattern. • Example: birds building their nests or the formation of groups for protection. An instinct should be distinguished from a reflex, which is a simple response of an organism to a specific stimulus . • such as the contraction of the pupil in response to bright light or the spasmodic movement of the lower leg when the knee is tapped . • The behavior in fixed way is called fixed action pattern (FAP). Fixed Action Patterns • A fixed action pattern (FAP) is a sequence of unlearned, innate behaviors that is unchangeable. • Once initiated, it is usually carried to completion. • A FAP is triggered by an external sensory stimulus known as a sign stimulus. Example-Lorenz and Tinbergen (1938) examined egg-rolling behavior in the greylag geese. • If the egg slipped away, she continued the motion. • Once started, the behavior must be completed in a specific way.
- 32. Instincts as the Neuromotor Apparatus – • The instincts are very common in our everyday life. For example, if a child is running and suddenly a buffalo comes in the way, the child either stops immediately or takes a turn the other way, and the sudden stopping is instinctive. Example of Instincts- 1. Nest building behaviour in Tailor- birds- • Tailorbirds get their name from the way they build their nests. • To make a cradle in which the actual nest is built, the edges of a large leaf are pierced and sewn together with plant fibre or spider silk. • Tailorbirds lay 2 to 5 eggs that are pastel blue with brown speckles. • Before the eggs hatch, the female will incubate them for about 12 days. • Both parents will be busy looking for food to feed and raise their brood of 2 to 5 chicks.
- 33. Types of Instincts 1.Closed instincts: • Closed instincts have fixed motor patterns which are preprogrammed. • They are already fed in the neural circuit from the beginning • They are not modified by the environment. Example-Spider spinning a web - By performing a series of behaviour patterns, a male spider can locate the female spider who is ready for courtship. The courtship signals include specific leg movements and the use of silk to capture the female in a special way. 2 . Open instincts: • Open instincts are the behavioural patterns which are functional when first performed, but they can be modified according to the changes in the environment. Example- Gull chicks responding to the cardboard models
- 34. Motivation Motivation is the psychological feature that arouses an organism to action toward a desired goal and elicits, controls, and sustains certain goal directed behaviors. • Example- An individual has not eaten, he or she feels hungry, and as a response he or she eats and diminishes feelings of hunger. • Motivation may be rooted in a basic need to minimize physical pain and maximize pleasure, or it may include specific needs such as eating and resting, or for a desired object. Conceptually, motivation is related to, but distinct from, emotion. 1. Intrinsic motivation -Intrinsic motivation refers to motivation that is driven by an interest or enjoyment in the task itself, and exists within the individual rather than relying on any external pressure. • Intrinsic motivation is based on taking pleasure in an activity rather than working towards an external reward. • Example -Students who are intrinsically motivated are more likely to engage in the task willingly as well as work to improve their skills, which will increase their capabilities. Students are likely to be intrinsically motivated if they: attribute their educational results to factors under their own control, also known as autonomy, learning to achieve good grades. 2. Extrinsic motivation -Extrinsic motivation refers to the performance of an activity in order to attain an outcome, which then contradicts intrinsic motivation. It is widely believed that motivation performs two functions. The first is often referred to as the energetic activation component of the motivation construct. The second is directed at a specific behavior and makes reference to the orientation directional component. • Common extrinsic motivations are rewards like money and grades, and threat of punishment.
- 35. Drives Drives are defined as the internal conditions taking place within the animal body which excite or arouse the individual to respond as well as do some action. Characteristic Features of Drive 1. Drives make the individual aware about its urge or feeling. 2. It involves the characteristics of premonition, deed and action. 3. Drives monitor the activities of an animal and decide its direction. 4. Drives motivate the direction of behaviour and thus changes the relation between the animal and its environment. 5. Sensitivity to certain stimuli is increased leading to competition. 6. Drives or motives cause an individual to search until an appropriate external condition is approached or achieved. 7. Drives direct the animal towards some goal which will satisfy its particular need. 8. It can also work as a general energizer making energy available for the activity required. 9. Drives make a part of the animal's arousal system.
- 36. Types of Drives A. Biological drives- • Its arise due to the basic needs which have to be fulfilled in order to keep the animals alive. • These biological needs are like those for water, food, oxygen, rest, etc. • Biological drives are internal factors and arise out of inherited structures present in all animals and every human being. • They are influenced by learning and cultural factors. B. Psychological motives- • The biological drives arise due to the physiological conditions of an individuals body. • It has been observed that besides the biological drives, the other important source of motivation is the psychology of an individual. • The ways and causes of an individual's thinking and beliefs constitute the psychological motives which serve as the drive on psychological level. • The human beings attitude about knowing more and more, i.e., curiosity, the feelings of love, hatred, aggression, enemity, etc.
- 37. Example of Biological drives- A . Hunger drive • The hunger sensations come from the region of stomach. • The hunger drive is the for want of food when the energy resulting from the food gets exhausted in the animal body. • The hunger drive is a complex behaviour. • Chemical nature of hunger drive: • The level of sugar in the blood plays an important role in hunger drive. • It acts on specific brain centres which excite major nerve leading to the stomach. This, in turn, causes strong stomach contractions. • The experiment that supports the concept of the control of hunger by blood sugar is in the fact that if insulin is injected in the blood, it results in the drop of blood sugar, thereby inducing stomach contractions and hunger. (Goodner and Russel, 1965) Role of hypothalamus in hunger- The hypothalamus of the brain significantly activates the hunger drive.
- 38. B . Thirst drive • The urge or sensation for want of water is called thirst drive. • Man can live for many days without food, but he cannot survive for a very long time without water. Thirst drive and behaviour: • The sensation of thirst over a long period of time worsens the state of an individual . • The experiments with rats have shown that they tend to find water more quickly, when thirsty, than the hungry ones to find the food. • The behaviour of thirsty animals is more stereotyped than the ones which are hungry. Mechanism of 'Thirst sensation': The animal body and tissues require constant water content to keep them in living state. So, the regular intake of water from time to time is necessary. As the water supply in the body becomes low, the tissues of the mouth and throat shrink and become dry. This dryness stimulates the nerve endings in the mouth and throat. This produces the feeling of thirst known as thirst drive. Role of hypothalamus in Thirst- The hypothalamus of the brain significantly activates the thirst drive.
- 39. C . Air hunger • Air hunger is realized when the body is deprived of the most basic requirement oxygen. • When there is any obstruction in the respiratory tract and the carbon-dioxide gets collected in the lungs, immediate discomfort and pain is felt. • The individual is unable to exhale carbon-dioxide and inhale properly. • air-hunger is caused by the presence of excess of CO₂, rather than less O₂. Importance of oxygen supply: • Oxygen is important for brain and nervous system. • The O₂ consumption takes place in small amounts, any deprivation of O₂, even for a minute, may cause neural damage. • At birth, when temporary asphyxiation takes place, it causes brain damage resulting in mental retardation. • At high altitudes O₂, starvation results in some intoxication which causes the individual to behave in an insane manner like shouting, fighting, laughing or crying. There is also loss of memory and the senses do not function properly. Role of hypothalamus in Thirst- The medulla, midbrain & hypothalamus of the brain significantly activates the air hunger.
- 40. D . Rest and sleep drive • When an individual overworks and its body involves a lot of muscular activity, it causes fatigueness. • This arises a need for rest and eventually the sleep. • Fatigue occurs not only due to the physical exertion but more from the mental stress, tensions or worry. • Tiredness or fatigue results from the chemical changes in the muscle and blood, that stimulate the nervous system and receptors. • If the fatigue is physical, then the rest usually ceases the persisting stimuli. If there is emotional fatigue, then, even the proper rest cannot relax the individual. Mechanism of fatigue and rest drive: • When an individual performs some activity, the muscle contraction takes place. • After a prolonged and steady contraction, the feeling of pain is experienced, such as headaches and eyestrain. • When muscle contraction takes place, there is chemical change in blood as well as increased concentration of lactic acid in muscles. • The increased contractions cut the blood supply, causing the accumulation of some chemical substance or neuro secretion released by stimulated nerves around the small blood vessels of the muscle. • Role of hypothalamus in Sleep- The hypothalamus of the brain & Nerve significantly activates the thirst drive.
- 41. E . Warm and Cold drives • Human body is sensitive to the warm and cold temperatures of its surrounding environment. • The changing weather or climatic conditions thus affect the animals as well as human beings. • Man responses through drives to avoid and escape the extreme temperature ranges. • Sensory receptors help in perceiving the sensation of warm and cold temperatures. Temperature regulation - The human drives for avoidance of cold and hot conditions is satisfied by the regulation of body temperature. (a) In cold conditions: • Secretion of thyroxine and adrenaline increases. • Muscular activity is increased. • Blood pressure rises. • Blood circulation takes place in such a way that the blood from the body surface is driven • to the deeper tissues. (b) In hot conditions: The hot sensations are felt when the surrounding climatic temperature is more or raised. • Body activity slows down. • Perspiration cools down the body surface. • The blood vessels at the surface of the body dilate and the large volume of blood is • exposed for cooling. • Blood circulation is increased. Role of hypothalamus in Sleep- The hypothalamus of the brain significantly activates the warm & cold drive.
- 42. B. Psychological motives-Different Psychological Drives- 1. Curiosity: • The desire to know or learn more about anything is known as curiosity. • It is inborn or innate learning without any training. • Curiosity is a very natural response which involve the visual recognition and tactile sensation for any object. • The individual or human being usually involves itself in activities. Example- Babies of monkeys, after two or three days of birth, show curiosity and exploration. 2. Achievement: • One of the significant psychological motives is the desire of achieving something which is outstanding. • The feeling of achievement involves the remarkable behaviour which shows efforts for performing the best, doing better than the others and others conquering something. Example-Child learns to achieve his mottos and aims by his own efforts. The spirit of achievement in animals and human beings give them great satisfaction and seeking success stimulate them to achieve more and more. 3. Reward power: • The need to achieve something is usually associated with the power of being praised, appreciated or in other words, being rewarded. • Human beings usually learn at a very early age, as how their particular act or deed is responded or rewarded. Example- Small babies learn to react to voices of the parents or to the specific words and actions.
- 43. References Animal behaviour- T.K. Saha Animal behaviour- C.J.Barnard Animal behaviour- Dr. A.K. Agarwal