Animal Behavior AP Biology meerkats Why study behavior
Animal Behavior AP Biology meerkats
Why study behavior? § Evolutionary perspective… u u part of phenotype acted upon by natural selection § lead to greater fitness? § lead to greater survival? § lead to greater reproductive success? AP Biology
What questions can we ask? § Proximate causes u u immediate stimulus & mechanism “how” & “what” questions § Ultimate causes u u evolutionary significance how does behavior contribute to survival & reproduction male songbird ® what triggers singing? how does he sing? why does he sing? § adaptive value u “why” questions Courtship behavior in cranes & why questions APwhat…how… Biology how does daylength influence breeding? why do cranes breed in spring?
The heart of Ethology……. 1. What is the basis of the behavior, including chemical, anatomical and physiological mechanisms? 2. How does development of the animal, from zygote to mature individual, influence the behavior? 3. What is the evolutionary history of the behavior? 4. How does the behavior contribute to survival and reproduction? u AP Biology Developed by Tinbergen in 1963
What is behavior? § Behavior u everything an animal does & how it does it § response to stimuli in its environment u innate behaviors § automatic, fixed, “built-in”, no “learning curve” § despite different environments, all individuals exhibit the behavior § ex. early survival, reproduction, kinesis, taxis u AP Biology learned behaviors § modified by experience § variable, changeable § flexible with changing environment
Innate behaviors § Fixed action patterns (FAP) male sticklebacks exhibit aggressive territoriality Sequence of unlearned acts that are triggered by a sign stimulus. u Usually carried out to completion u AP Biology attack on red belly stimulus court on swollen belly stimulus
Complex Innate behaviors § Use of environmental cues to carry out behavior u u u Migration, Hibernation, Estivation, Courtship “migratory restlessness” seen in birds bred & raised in captivity navigate by sun, stars, Earth magnetic fields Sandpiper Monarch AP Biology migration Bobolink ancient fly-ways Golden plover
Innate: Directed movements § Taxis u Response movement toward (positive taxis) or away from (negative taxis) a stimulus § phototaxis § chemotaxis § Kinesis Random movement in response to a stimulus u AP Biology ex: stopping, starting, or turning. ex: sowbug activity increases when conditions are dry.
Learning: Imprinting § Young animals go through a “critical period” whereafter they follow the organisms present during the period. AP Biology Konrad Lorenz
Learning: Associative § learning to associate a stimulus with a consequence u operant conditioning § trial & error learning § associate behavior with reward or punishment § ex: learning what to eat u classical conditioning AP Biology § Pavlovian conditioning § associate a “neutral stimulus” with a “significant stimulus”
Operant conditioning § Skinner box Basic animal training with rewards for behaviors. mouse learns to associate behavior (pressing lever) with reward (food pellet) AP Biology
Learning: Habituation § Loss of response to stimulus u u u “cry-wolf” effect decrease in response to repeated occurrences of stimulus enables animals to disregard unimportant stimuli § ex: falling leaves not triggering fear response in baby birds; animals standing next to hwy AP Biology
Learning: Spatial § Establishment of memories that reflect the physical structure of the environment. Squirrels using physical markers to find buried food. u Wasps using physical markers to find their nest. u AP Biology
Learning: Problem-solving/Cognition § Involves reasoning, awareness, recollection and judgment Insight learning crow tool use sea AP Biology otter
Social behaviors § Interactions between individuals that develop into evolutionary adaptations u u u AP Biology communication / language agonistic behaviors dominance hierarchy cooperation altruistic behavior
Language § Honey bee communication dance to communicate location of food source u waggle dance u AP Biology
Communication by song § Bird song species identification & mating ritual u mixed learned & innate u critical learning period u § Insect song mating ritual & song u innate, genetically controlled u AP Biology Red-winged blackbird
Social behaviors § Agonistic behaviors u threatening & submissive rituals § symbolic, usually no harm done u AP Biology ex: territoriality, competitor aggression
Social behaviors § Dominance hierarchy u social ranking within a group § pecking order AP Biology
Social behaviors § Cooperation u working together in coordination Pack of African dogs hunting wildebeest cooperatively AP Biology White pelicans “herding” school of fish
Social interaction requires communication § Pheromones u chemical signal that stimulates a response from other individuals § alarm pheromones § sex pheromones AP Biology
Pheromones Female mosquito use CO 2 concentrations to locate victims marking territory Spider using moth sex pheromones, as allomones, to lure its prey AP Biology The female lion lures male by spreading sex pheromones, but also by posture & movements
Behaviors should increase fitness! § Foraging behavior – cost and benefits § Mating systems – monogamy vs. § § § polygamy Certainty of paternity Agonistic behavior Game theory – California lizard species n Orange outcompetes blue Blue outcompetes yellow Yellow outcompetes orange AP Biology
Social behaviors § Altruistic behavior u u reduces individual fitness but increases fitness of recipient kin selection § increasing survival of close relatives passes these genes on to the next generation AP Biology How can this be of adaptive value? Belding ground squirrel
Make sure you can… § Provide proximate and ultimate § § explanations for behaviors Compare innate and learned behaviors and provide examples of each Describe how a particular behavior can evolve Explain how particular behaviors contribute to an organism’s fitness Explain how altruistic behaviors can evolve in a population AP Biology
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