Animal Behavior What is behavior & Why study it? Behavior everything an animal does & how it does it response to stimuli in its environment innate = inherited or developmentally fixed learned = develop during animal s lifetime Why study behavior? part of phenotype acted upon by natural selection lead to greater fitness? greater reproductive success? greater survival? meerkats 2006-2007 What questions do we ask? Proximate causes immediate stimulus & mechanism how & what questions Ultimate causes evolutionary significance how does behavior contribute to survival & reproduction adaptive value why questions male songbird what triggers singing? how does he sing? why does he sing? Courtship behavior in cranes how does day length influence breeding? AP Biology what how & why questions why do cranes breed in spring? 1941 1973 Ethology pioneers in the study of animal behavior Karl von Frisch Niko Tinbergen Konrad Lorenz Types of behaviors Innate behaviors automatic, fixed, built-in despite different environments, all individuals exhibit the behavior triggered by a stimulus Learned behaviors modified by experience triggered by a stimulus variable male sticklebacks exhibit aggressive territoriality Innate behavior Fixed action patterns (FAP) sequence of behaviors essentially unchangeable & usually conducted to completion once started sign stimulus the releaser that triggers FAP does lipstick create a supernormal stimulus in humans attack on red belly stimulus court on swollen belly stimulus 1
Fixed Action Patterns (FAP) Directed movements Taxis Digger wasp egg rolling in geese change in direction automatic movement toward (positive taxis) or away from (negative taxis) a stimulus phototaxis chemotaxis Kinesis Do humans exhibit Fixed Action Patterns? The eyebrow-flash Migration Complex behavior, but still innate change in rate of movement in response to a stimulus Imprinting Learning at a specific critical time migratory restlessness seen in birds bred & raised in captivity navigate by sun, stars, Earth magnetic fields forming social attachments both learning & innate components Sandpiper Monarch migration Bobolink ancient flyways Golden plover Conservation Conservation biologists have taken advantage of imprinting by young whooping cranes as a means to teach the Wattled crane conservation birds a migration route. A pilot wearing teaching cranes to migrate a crane suit in an Ultralight plane acts as a surrogate parent. Konrad Lorenz Critical period Sensitive phase for optimal imprinting As As aa brood brood parasite, parasite, the the Cuckoo Cuckoo never never learn learn the the song song of of their their species species as as aa nestling. nestling. Song development Song development is is totally totally innate. innate. imprinting imprinting in in humans? humans? 2
Learned behavior Associative learning Operant conditioning Skinner box learning to associate one feature of the environment (stimulus) with another operant conditioning trial & error learning associate behavior with B. F. Skinner reward or punishment classical conditioning Pavlovian conditioning associate a neutral QuickTime QuickTime and andaa TIFF TIFF(Uncompressed) (Uncompressed)decompressor decompressor are areneeded neededtotosee seethis thispicture. picture. stimulus with a significant stimulus QuickTime QuickTime and andaa TIFF TIFF(Uncompressed) (Uncompressed)decompressor decompressor are areneeded neededtotosee seethis thispicture. picture. mouse learns to associate behavior (pressing lever) with reward (food pellet) Classical conditioning Habituation Loss of response to Ivan Pavlov s dogs connect reflex behavior (salivating at sight of food) to associated stimulus (ringing bell) stimulus cry-wolf effect learn not to respond to repeated occurrences of stimulus Thinking & problem-solving Do other animals think? Interactions between individuals problem-solving tool use develop as evolutionary adaptations language agonistic behaviors dominance hierarchy altruistic behavior crow 3
Language Honey bee Communication by song Bird song communication species identification & mating ritual mixed learned & innate critical learning period dance to communicate location of food source waggle dance Insect song Red-winged blackbird mating ritual & song innate, genetically controlled Agonistic behaviors Dominance hierarchy threatening & submissive rituals symbolic, usually no harm done social ranking within a group pecking order Social interaction requires communication Altruistic behavior Pheromones reduces individual fitness but increases fitness of recipient kin selection chemical signal that stimulates a response from other individuals alarm pheromones sex pheromones Belding ground squirrel I would lay down my life for 2 brothers or 8 cousins! How can this be of adaptive value? 4
Pheromones Pheromones Female mosquito use CO2 concentrations to locate victims marking territory Spider using moth sex pheromones, as allomones, to lure its prey Human pheromones? The female lion lures male by spreading sex pheromones, but also by posture & movements Cooperation Colonial mammals convergent evolution: bees, ants, termites mole rats Naked mole rats Pack of African dogs hunting wildebeest cooperatively underground colony, tunnels queen, breeding males, non-breeding workers hairless, blind Picture a hot dog that's been left in a microwave a little too long add some buck teeth at one end, and you've got a fairly good idea of what a Naked Mole Rat looks like. White pelicans herding school of fish Territoriality Any Questions?? 2006-2007 5
Mating & parental behavior Genetic influences changes in behavior at different stages of mating pair bonding competitor aggression Environmental influences modifies behavior quality of diet social interactions learning opportunities 6