Copyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsOverview: Studying Behavior• Humans have probably studied animal behaviorfor as long as we have lived on Earth• As hunters, knowledge of animal behavior wasessential to human survivalCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• Behavioral ecology extends observations ofanimal behavior by studying how such behavior iscontrolled and how it develops, evolves, andcontributes to survival and reproductive successCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsConcept 51.1: Behavioral ecologists distinguishbetween proximate and ultimate causes of behavior• Scientific questions about behavior can be dividedinto two classes:– Those that focus on the immediate stimulusand mechanism for the behavior– Those that explore how the behaviorcontributes to survival and reproductionCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsWhat Is Behavior?• Behavior is what an animal does and how it does it• Behavior includes muscular and nonmuscularactivityLE 51-2Dorsal finAnal finCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• Learning is also considered a behavioral processCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsProximate and Ultimate Questions• Proximate, or “how,” questions focus on:– Environmental stimuli that trigger a behavior– Genetic, physiological, and anatomicalmechanisms underlying a behavior• Ultimate, or “why,” questions focus on evolutionarysignificance of a behaviorCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsEthology• Ethology is the scientific study of animal behavior,particularly in natural environmentsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• Ethologists developed a conceptual frameworkdefined by a set of questions• These questions highlight the complementarynature of proximate and ultimate perspectivesCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsFixed Action Patterns• A fixed action pattern (FAP) is a sequence ofunlearned, innate behaviors that is unchangeable• Once initiated, it is usually carried to completion• A FAP is triggered by an external sensory stimulusknown as a sign stimulusCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• In male stickleback fish, the stimulus for attackbehavior is the red underside of an intruderCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• When presented with unrealistic models, as longas some red is present, the attack behavior occursLE 51-4BEHAVIOR: A male stickleback fish attacks other malesticklebacks that invade its nesting territory.PROXIMATE CAUSE: The red belly of the intruding male acts asa sign stimulus that releases aggression in a male stickleback.ULTIMATE CAUSE: By chasing away other male sticklebacks,a male decreases the chance that eggs laid in his nestingterritory will be fertilized by another male.Copyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsImprinting• Imprinting is a behavior that includes learning andinnate components and is generally irreversible• It is distinguished from other learning by asensitive period• A sensitive period is a limited developmentalphase that is the only time when certain behaviorscan be learnedCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• An example of imprinting is young geese followingtheir mother• Konrad Lorenz showed that when baby geesespent the first few hours of their life with him, theyimprinted on him as their parent• There are proximate and ultimate causes of thistype of behaviorVideo: DucklingsVideo: DucklingsLE 51-5BEHAVIOR: Young geese follow and imprint on their mother.PROXIMATE CAUSE: During an early, critical developmentalstage, the young geese observe their mother moving awayfrom them and calling.ULTIMATE CAUSE: On average, geese that follow andimprint on their mother receive more care and learnnecessary skills, and thus have a greater chance ofsurviving than those that do not follow their mother.Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• Conservation biologists have taken advantage ofimprinting in programs to save the whooping cranefrom extinctionCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsConcept 51.2: Many behaviors have a stronggenetic component• Biologists study how genes and environmentinfluence development of behavioral phenotypes• Innate behavior is developmentally fixed andunder strong genetic influenceCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsDirected Movements• Many animal movements are under substantialgenetic influence• They are called directed movementsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsKinesis• A kinesis is a simple change in activity or turningrate in response to a stimulus• For example, sow bugs become more active in dryareas and less active in humid areasLE 51-7aKinesis increases the chance that a sow bug will encounter and stayin a moist environment.Dry openareaMoist siteunder leafCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsTaxis• A taxis is a more or less automatic, orientedmovement toward or away from a stimulus• Many stream fish exhibit positive rheotaxis; theyautomatically swim in an upstream direction• This taxis prevents them from being swept awayand keeps them facing the direction from whichfood will comeLE 51-7bPositive rheotaxis keeps trout facing into the current, the directionfrom which most food comes.Directionof rivercurrentCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsAnimal Signals and Communication• In behavioral ecology, a signal is a behavior thatcauses a change in another animal’s behavior• Communication is the reception of and responseto signalsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings• Animals communicate using visual, auditory,chemical, tactile, and electrical signals• The type of signal is closely related to lifestyle andenvironmentCopyright © 2005 Pearson Education, Inc. publishing as Benjamin
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