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Animal Behavior Orientation behaviours: Kineses Taxes

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Environmental Stimuli A slater retreating to a daytime crevice could be responding to the dampness, darkness or coolness. 2 Can experiment to determine which factors influence behaviour

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Experiments Choice chambers offer alternative conditions Fair test - all others factors are kept the same. 3 Can test effect of temperature, light, humidity

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Simple Responses - immediate surroundings Kineses and Taxes have an immediate benefit e.g. a slater moving into a damper place. 4

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Taxes Movement towards or away from a stimulus 5 Negative = away Positive = towards

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Taxes Snails climb vertically upwards. Negative geotaxis

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Taxes Mosquitoes home in on warm flesh. Positive thermotaxis

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Taxes Blowfly maggots move rapidly away from a directional light source. Negative phototaxis

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Positive phototaxis Positive phototaxis = movement towards the light e.g. many swimming algae 9

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Positive Chemotaxis eg male moths following a pheromone trail given off by females

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Negative Phototaxis 11 Slime Mold The direction of the light source is indicated by white rectangles. e.g. earthworms

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Positive chemotaxis When a capillary tube filled with glucose is placed in a medium containing E. coli, the bacteria alter their locomotion so that they congregate near the opening of the tube.E. coli 12 Mosquitoes towards people along CO 2 gradient

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Positive rheotaxis Movement against a current e.g. salmon migrating upstream 13

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Kinesis Animals have specific needs (eg 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 14

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Search methods Undirected search: animal moves in a more or less straight line through unsuitable habitat. Directed search: when it begins to perceive better conditions (the blue area) it slows down and turns sharper angles to stay in the vicinity of the improved conditions. 15

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16 stimulus random movements to get away slow down as animal gets further away

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17 stimulus ALTERNATIVELY animal moves directly away in a straight line

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Hydrokinesis Orthokinesis Orthokinesis = stimulus intensity determines speed e.g. slaters rate of movement is inversely proportional to the humidity

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Thermokinesis Klinokinesis Klinokinesis = stimulus intensity determines rate of turning eg lice turn less often at 30 - straight line. Human skin temp is about 35 lice more likely to linger at 35. Human body louse 35 o 30 o Orthokinesis and klinokinesis movies