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Behavior in living organisms Behavior in one celled organisms Behavior in plants Behavior in animals What is a stimulus? • Stimulus is an information from the inside or outside of the organism. Stimulus(stimuli) creates a response (physiological or behavioral) in the organism. • Stimuli triggers a special kind of behavior for each species. Only that species respond to that stimuli. What is behavior? • Behavior is a way of response to the stimuli. • Behavior supports the survival of the organism. • Prey escapes from the predator. Predator follows prey. Plants respond to light. • The science which investigates behavior is called ethology. Instinctive (natural) behavior • That is performed without having been learned. • Feeding, reproduction, bird song • Reflexes and instincts Learned behavior • That is changed with experience. • Imprinting • Conditioning • Trial-error • Habituation Behavior in one celled organisms Behavior -depending on the direction of the stimuli • • • • • • • + or – Replacement (taxis) + chemotaxis:toward - chemotaxis: away + phototaxis: - phototaxis: geotaxis Behavior -not depending on the direction of the stimuli • Nasty • The direction of the stimulus is not important. Cell gives the same response • Geonasty-geonastic Behavior in plants Behavior -depending on the direction of the stimuli • • • • Tropism + phototropism: - geotropism:stem - chemotropism: against chemicals • Hydrotropism: • heliotropism Behavior -not depending on the direction of the stimuli • Nasty • Geonasty-geonastic photonastic • Thermonastic • Sismonastic Tropism types • Chemotropism, movement or growth in response to chemicals • Geotropism or Gravitropism, movement or growth in response to gravity • Hydrotropism, movement or growth in response to moisture or water • Heliotropism, movement or growth in response to sunlight • Phototropism, movement or growth in response to light • Thermotropism, movement or growth in response to temperature • Thigmotropism, movement or growth in response to touch or contact • http://en.wikipedia.org/wiki/Tropism • http://www.science.mcmaster.ca/psycholo gy/psych1a6/1aa3/EvoPsych/lec1-2.htm • http://www.animalbehavioronline.com/ • http://www.bio.davidson.edu/people/vecas e/Behavior/index.html Behavior in animals Reflexes • Reflexes are sudden and fixed behaviors. (reaction) controlled by ??? • The reflexes are not performed conciously. Spinal cord is involved for these kind of behaviors not brain. • Grasp reflex of a baby important for catching mother. Instincts • Instinctive behavior is performed without being learned. • It is a concious behavior. That person is sure(concious) about what he is doing. Brain is involved. • Migration, nesting, looking after youngs • Endocrine and nervous system involve in behavior. The most important centers in the body are hypophysis and hypothalamus. What is learning? • The behavioral changes as a result of the experiences form learning. Learning causes a change of behavior. • Imprinting • Conditioning • Trial-error • Habituation Imprinting • Learning occurring at a particular age or a particular life stage that is rapid. • Young Geese of Konrad Lorenz, learn the characteristics of him as parent. • "critical period" of about 36 hours shortly after hatching is best for imprinting of geese. Conditioning • Conditioning is a type of associative learning. • Ivan Pavlov described the learning of conditioned behavior as being formed by pairing stimuli to condition an animal into giving a certain response • Food (Unconditioned.Stimulus) => Salivation (U.R.) Natural response. • Food (U.S.) + Bell (Neutral.S.) => Salivation (U.R.) After repeating the pairing a few times. • Bell (Conditioned.S.) => Salivation (C.R.) Learning occurs. Dogs salivate without food. Trial-error (operant conditioning) • When first put into the maze, the mice took a long time to escape. With experience, ineffective responses occurred less frequently and successful responses occurred more frequently, enabling the mice to escape in less time over successive trials . Habituation • There is a progressive diminution (reduction) of behavioral response with the repetition of a stimulus . The learned suppression of response is habituation . • A short amount of time after dressing, the stimulus the weight of clothes creates is 'ignored' by the nervous system and we become unaware of it. Biological clock • Biological Clocks are physiological systems that enable organisms to live in harmony with the rhythms of nature, such as the cycles of day and night and of the seasons. • Sleeping, winter sleep, migration are regulated by biological clock. Social Behavior • Living in a social group can provide benefits. Shielding against predators, cooperative defenses. • Social behavior results from the interactions among two or more individuals. • Cooperation, competition, predation, defense are social behaviors. • Social groups have hierarchies. In the hierarchy, each individual knows his own responsibilities. Societies • The individuals of the same species effectively interact with each other in the societies. Bees, birds, wolves, human, ants • There is a division of labor. Communication • Individuals within the society communicate with each other. This is unavoidable for gathering, feeding, defense, reproduction. • Sound, smell(pheremones), movement, mimics are important communication ways. Communication styles • Dogs- Urination • Birds- singing patterns and songs • Bees- The 'round dance' reveals a food source not far away. The 'figure eight' dance reveals a distant food source. The 'round dance' reveals a food source not far away. The 'figure eight' dance reveals a distant food source.