Chapter 51 Animal Behavior Why do we do
Chapter 51 ~ Animal Behavior
Why do we do the things we do? • Ethology - study of animal behavior • Behavior – everything an animal does and how it does it -response to environmental stimulus 2 Types: Innate – inherited or developmentally fixed Learned – develop during animal’s lifetime Why study behavior? • • Part of phenotype Acted upon by natural selection - effects reproductive success, genetic fitness, survival rate Supernormal stimulus
What questions do we ask? Causes: • proximate~ physiological & genetic mechanisms of behavior IMMEDIATE “How & What” of behavior What triggers singing? • ultimate~ evolutionary significance of behavior – survivial, reproduction, adaption LONG TERM “Why” of behavior Why does he sing? What, How, and Why of courtship behavior?
Pioneers of Ethology 1973 Nobel Prize: Konrad Lorenz, Niko Tinbergen, Karl von Frisch Studied instinctual behaviors “Imprinting” Originated “proximate” & “ultimate” causations. Studied “supernormal stimulus” Studied sensory perception in honey bees “waggle dance”
Innate vs. Learned – a closer look Innate behaviors • Automatic/Built – in • Despite different environments, all individuals exhibit the behavior • Triggered by stimulus Learned behaviors • Modified by experience • Variable • Triggered by a stimulus
Innate Behaviors • Fixed Action Patterns (FAP): sequence of acts; unchangeable; carried to completion (Dog circling bed, eyebrow flash humans and other primates, egg retrieval in birds, male stickleback aggression & red) • Circadian Rhythm – Daily behavior cycles, light/dark response • Migration – complex navigation via sun, stars, earth’s magnetic field • Imprinting – limited learning social attachments at ‘critical period’ • Directed Movements – TAXIS: specific, directed movement (cockroaches scattering away from light, drosophila crawling to top of container) KINESIS: random, undirected (pillbugs wandering to find moist side of choice chamber)
Learned Behavior LEARNING: change in behavior as result of experience • HABITUATION~ loss of responsiveness to stimuli; learn NOT to respond - simple learning (annoying sounds, lights, etc) • ASSOCIATIVE LEARNING: • classical conditioning~ Pavlov’s dogs behavior associated neutral stimulus with significant stimulus. Works with involuntary behavior. • operant conditioning (trial and error)~ “Skinner’s box” behavior associated with reward or punishment. Works with voluntary behavior.
Behaviors in Action 2 types: Innate/Instinctive (genetic not learned): Fixed Action Pattern Baby Joey in Pouch Interaction of innate & learned: Duck & Dog - Imprinting Learned (result of experience): Classical Conditioning “The Office” Operant Conditioning “The Big Bang” Causes of each? Proximate? Ultimate?
Learned behavior II: Social behavior • Interactions between individuals. -Develop as evolutionary adaptations • Agonistic behavior~ contest behavior determining access to resources; submissive and threatening rituals usually no harm done • Dominance hierarchy~ social ranking/linear “pecking order” that establishes an individual’s place in social group. Division of labor makes cooperation more efficient and effective. • Altruistic behavior~ unconscientiously selfless behavior that may be disadvantageous to individual but beneficial others. ? ? ? Cats play patty cake
Reconciling altruism & natural selection • Natural selection works on populations NOT individuals • Altruism may hurt individual but helps population • Kin selection-increase probability of survival of relatives at expense of individual Why do Belding ground squirrels make alarm call? Why females more than males?
Lab 12: Fruit Fly Behavior 1. Construct choice chamber from 2 plastic 1 L soda bottles & toss in 10 – 20 fruit flies. Count flies inside. Wait 5 minutes. 2. Expose specific areas to different treatments of your choice & record # flies on each side over period of time 3. Graph results and perform chi square analysis. 11
Experimental Design 101 • • State Hypothesis Identify All Variables Identify a Sample Organism Identify the control(s) Explain how you will to measure data Provide expected data Interpret your data (with a sentence & graph) Understand importance of repetition & sample size.
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