Download Behavioral Responses

Behavioral Responses
Plant Responses
 Phototropism:* growth response to light
o Cells elongate (grow) on the dark side & less on the light side

In response to auxin (plant hormone); transported from tip down stem, changes acidity of wall
causing growth
 Gravitropism:* growth in response to gravity
o Organelles settle to bottom, growth of bottom of cell inhibited or top promoted
 Thigmotropism:* directional growth in response to touch
o Tendrils coiling, use objects as support to grow
 Photoperiodism:* response to light, determines time of year
o Circadian rhythm:* innate cycle of about 24 hrs, controlled by biological clock
o Phytochrome:* protein in leaves, contain light absorbing components.
o Short Day Plants: flower after late summer, prefer long nights

Require long uninterrupted darkness beyond a critical length to flower

At night phytochrome is Pr & dawn breaks Pfr , night Pfr degrades & Pr made
o Long Day Plants: flower early spring, prefer short nights

Require nights shorter than a critical length to flower

Prefer nights interrupted with red light (perceived as short length night)
o Disappearance of Pfr may signal night & appearance of day to regulate circadian rhythms by resetting clock
Animal Behavior
 Behavior: a response to a stimulus
o Results from genes (evolves) and environment
o Survival values: reason for the behavior; helps individuals or species survive.

Foraging, Defensive, Parental Care, Courtship, Migratory & Territorial
 Innate Behavior* http://www.pigeon.psy.tufts.edu/psych26/images/gray.mov
o Programmed in genes
o Performed the same by all individuals of the same species
o Fixed Action Pattern:* set sequence of behaviors that continues to completion once triggered

Does not respond to feedback

Sign stimulus:* triggers an FAP, cue in the environment, AKA releaser
o Reflex: single movement of one body part
o Taxis:* movement of whole body, either toward or away from a stimulus
 Learned Behavior: change in behavior because of experience
o Not all behaviors begun late in life are learned, results from maturation
o Social, observational or modeling: watching the behavior of others
o Insight/reasoning: responding correctly the first time by gaining insight through unrelated previous
experience
o Habituation:* learning to ignore an unimportant repeated stimulus – prevents wasting energy
o Imprinting:* learning programmed to occur during a specific time very early in life – called sensitive period

Konrad Lorenz, gosling
o Associative Learning:* links one stimulus with another, changing behavior in response

Classical Conditioning: replace natural stimulus with artificial one, response remains the same
▫ Ivan Pavlov & his dog

Operant conditioning (trial and error):* increase or decrease a behavior by following it with a
reward or punishment
▫ BF Skinner & Skinner box
 Social Behavior:* interaction of organisms of the same species

Communication: transmission of information between individuals

Agnostic Behavior:* series of threats and actual combat to settle disputes – centered over resources
(mates, food, territory)
o Courtship: to attract and maintain a mate
o Territoriality: protecting an area for exclusive use
o Dominance Hierarchy:* aggressive and submissive behaviors that establish and maintain a ranking
o Altruism:* self-sacrificing behavior that reduces the fitness of one to benefit the fitness of the population

Kin Selection:* individuals help relatives to reproduce rather than producing its own offspring