Innate and learned behavior 7 Option E 3

Innate and learned behavior 7 Option E. 3

Assessment Statements E. 3. 1 Distinguish between innate and learned behaviour. E. 3. 2 Design experiments to investigate innate behaviour in invertebrates, including either a taxis or a kinesis. E. 3. 3 Analyse data from invertebrate behaviour experiments in terms of the effect on chances of survival and reproduction. E. 3. 4 Discuss how the process of learning can improve the chance of survival. E. 3. 5 Outline Pavlov’s experiments into conditioning of dogs. E. 3. 6 Outline the role of inheritance and learning in the development of birdsong in young birds.

Two types of scientists Ethologists study the behavior of animals in their natural environment Examine patterns of behavior that affect an animal’s life Psychologists Study the behavior of animals in an artificial environment Collect data on learning and motivation that could never be measured in the natural environment

Etymology ethologist from Greek: ἦθος, ethos, "character"; and -λογία, -logia psychologist Ancient Greek ψυχή (psukhē), “‘soul’”) + logia (“‘study of’”)

Innate behavior Develops independently of environmental context Spider spins web correctly the first time Infants suckle innately Controlled by genes and inherited from parents Some performed in certain order Mating behavior of the three-spined stickleback fish

Learned behavior Not genetically programmed Process of gaining knowledge or skills or modifying existing knowledge or skills Learning can only be measured by performance Ex. Pedal pushing results in gain of food Behavior output is not always easily seen, therefore, learning is sometimes difficult to measure

Comparison Innate behavior Learned behavior Develops independently of the environmental context Dependent on the environmental context of the animal for development Controlled by genes Not controlled by genes Inherited from parents Not inherited from parents Developed by natural selection Develops by response to an environmental stimulus Increases chance of survival and reproduction May or may not increase chance of survival and reproduction

Investigating innate behavior in invertebrates Innate behaviors can be measured as the animals respond to environmental stimuli Two basic kinds of movement are seen in invertebrate animals: Taxis Kinesis

Taxis A directed response to a stimulus If the animal’s body is directed toward the stimulus, it has a positive response If the animal’s body is directed away from the stimulus, it has a negative response Taxes are identified by the type of stimuli to which the organism is responding

Chemotaxis: response to chemicals in the environment; experiments involving variation in p. H, dissolved drugs, food, pesticides Phototaxis: response to light; experiments involving different wavelengths of light, intensities, and different types of bulb Gravitaxis: response to gravity; experiments with organism in container that is turned upside down or on a turntable Rheotaxis: response to water current; experiment involving animals with and against current Thigmotaxis: response to touch; experiment involving different types of material to touch an organism

Commonly used organisms Planaria Euglena Flatworm which lives in lakes and ponds under leaves and rocks and hides for protection Single-celled protist Has flagellum which propels it quickly through the water Active and move by contraction of muscle fibers in their body Has an eyespot which is stimulated by light Simple nervous system; eyespots which contain photoreceptors; chemoreceptors which respond to certain chemicals (food) Has chlorophyll

Kinesis Movement in response to a nondirectional stimulus, such as humidity Rate of movement of the animal depends on the intensity of the stimulus, not its direction Animal does not move toward or away from the stimulus buy randomly until it is in a more comfortable spot

Orthokinesis: when an organism moves slowly or rapidly (changes speed) in response to the stimulus but does not move towards the stimulus Klinokinesis: when an organism turns slowly or rapidly in response to the stimulus but it does not move towards the stimulus

Commonly used organisms Isopods (woodlice; rolly pollies) Terrestrial crustaceans Breath with gills; need moisture in order to breath Live in damp places; die if exposed to dry conditions for a long period of time

Learning improves the chance of survival Learning occurs most easily when it results in the animal’s survival Imprinting – process by which young animals become attached to their mother within the first day or so after hatching or birth; assures that the young stay close to their mother for protection and as a source of food

Food hoarding – store food when it is plentiful and return when there is a shortage; allows them to stay nourished even in times of food shortages Song – attracts a mate and deters rival males How to get food Mimicry

Pavlov and conditioning Classical conditioning can be used to modify a reflex response Russian physiologist Ivan Pavlov designed experiments to illustrate classical conditioning His subjects were dogs

Salivation is a reflex response to the presence of food in the mouth Food is unconditional stimulus which elicits salivation which is unconditional response Neutral stimulation that Pavlov employed was the ringing of a bell He rang the bell (conditioned stimulus) just before the dog tasted the food After training, the could ring the bell (CS) and the dog would salivate (conditioned result) Dog had learned to salivate to the neutral stimulus

Learning of birdsong in young birds Each species of bird has a species-specific song which is inherited Birds learn to improve the song they have inherited Birds are able to sing due to their vocal organ, called the syrinx located at the bottom of their trachea Birds control the pitch by altering the tension in the membranes of the syrinx If birds are kept in a lab and denied any auditory stimulation, they produce a crude song

After hatching, there is a memorization phase in which the bird is silent but listening to the song of his species from adults (males) He attempts to match his template to the full adult song Phase if over within 100 days (sensitive period) 2 nd phase is motor phase in which he practices singing, continuing to listen to his own song and match it to his father’s As he becomes sexually mature, his song will become perfected and he will begin to search for a mate Crude template is innate; adult song is learned