Chapter 51: Behavioral EcologyChapter 51: Behavioral EcologyBehavioral ecologyBehavioral ecologyHow behavior develops, evolves, & contributes How behavior develops, evolves, & contributes to survival & reproductive successto survival & reproductive successEthologyEthologyStudy of animal behavior (in the animal’s natural Study of animal behavior (in the animal’s natural environment)environment)BehaviorBehaviorWhat an animal does & how the animal does itWhat an animal does & how the animal does itCause of behaviorCause of behavior

ProximateProximateEnvironmental trigger for behavior as well as genetic, Environmental trigger for behavior as well as genetic, physiological, & anatomical mechanism for the act physiological, & anatomical mechanism for the act ““how”how”

UltimateUltimateAddresses evolutionary significance for behaviorAddresses evolutionary significance for behavior““why”why”

Types of behaviorTypes of behavior InstinctInstinct

Inherited behavior; developmentally fixedInherited behavior; developmentally fixed Examples: Examples:

Directional movementsDirectional movements Kinesis- change in activity or rate in response to a Kinesis- change in activity or rate in response to a

stimulus (ex. sow bugs more active in humidity)stimulus (ex. sow bugs more active in humidity) Taxis- oriented movement toward or away from a Taxis- oriented movement toward or away from a

stimulus (ex. Trout face current)stimulus (ex. Trout face current) Migration (ex. Migratory restlessness in blackcap birds)Migration (ex. Migratory restlessness in blackcap birds)

Animal Signals & CommunicationsAnimal Signals & Communications Signal=behavior that causes a change in another Signal=behavior that causes a change in another

animal’s behavioranimal’s behavior Communication= transmission of, reception of, & Communication= transmission of, reception of, &

response to signalsresponse to signals visual visual TactileTactile electrical signals electrical signals

ChemicalChemical Releaser Pheromones- cause immediate behavior Releaser Pheromones- cause immediate behavior

changechange Primer pheromones- cause physiological changePrimer pheromones- cause physiological change

AuditoryAuditory which communication is used is dependant on animal’s which communication is used is dependant on animal’s

environment & lifestyleenvironment & lifestyle

Fixed Action PatternsFixed Action Patterns Sequence of unlearned, unchangeable Sequence of unlearned, unchangeable

behavioral acts carried out to completion behavioral acts carried out to completion once initiatedonce initiated

Triggered by sign stimulus (external sensory Triggered by sign stimulus (external sensory stimuli)stimuli)

Ex. Male stickleback fish aggressively Ex. Male stickleback fish aggressively defends territory when triggered by red colordefends territory when triggered by red color

Imprinting Imprinting Behavior that involves learning & innate Behavior that involves learning & innate

components & is irreversiblecomponents & is irreversible Sensitive period: Brief period in which Sensitive period: Brief period in which

behavior can be learned (typically from behavior can be learned (typically from parent)parent)

Ex. Graylag gosling accept any moving object Ex. Graylag gosling accept any moving object as mother during 1as mother during 1stst 2 days 2 days

Learning Learning Modification of behavior based on specific Modification of behavior based on specific

experiencesexperiences HabituationHabituation

loss of responsiveness to stimuli that convey little loss of responsiveness to stimuli that convey little or no information or no information

““cry-wolf” effectcry-wolf” effect

Spatial LearningSpatial Learning Modification of behavior based on experience with Modification of behavior based on experience with

spatial structure in the environment (location of nest, spatial structure in the environment (location of nest, hazards, food, mates)hazards, food, mates)

Use landmarks as location indicatorsUse landmarks as location indicators Cognitive mapsCognitive maps

Internal representation/code of the spatial Internal representation/code of the spatial relationships between objects in an animal’s relationships between objects in an animal’s surroundingssurroundings

Associate learning Associate learning Ability to associate one feature of the environment Ability to associate one feature of the environment

(stimulus) with another (the response it produced)(stimulus) with another (the response it produced) Classical conditioning- stimulus is associated with a reward Classical conditioning- stimulus is associated with a reward

or punishment or punishment Operant conditioning/trial & error learning- animal associates Operant conditioning/trial & error learning- animal associates

one of its own behaviors with reward or punishmentone of its own behaviors with reward or punishment Cognition & problem solving Cognition & problem solving

Ability of an animal’s nervous system to perceive, Ability of an animal’s nervous system to perceive, store, process, & use information gathered by sensory store, process, & use information gathered by sensory receptorsreceptors

**Natural Selection can act on behavior **Natural Selection can act on behavior that has a genetic componentthat has a genetic component

Behavioral Variation can exist inBehavioral Variation can exist in prey selectionprey selection aggressive behavior aggressive behavior Parental care Parental care Migratory patternsMigratory patterns

**Natural selection most often acts on **Natural selection most often acts on behaviors that increase survival & behaviors that increase survival & reproductive fitness….reproductive fitness…. Foraging behaviorForaging behavior Mating behavior & choiceMating behavior & choice

Foraging BehaviorForaging Behavior Optimal foraging theoryOptimal foraging theory

food obtaining behavior is a compromise between the benefits food obtaining behavior is a compromise between the benefits of nutrition & the cost of obtaining foodof nutrition & the cost of obtaining food

Costs include- energy expenditure, risk of own predationCosts include- energy expenditure, risk of own predation Examples: Examples:

Northwestern crows flying up to break open shells of molluscsNorthwestern crows flying up to break open shells of molluscs Bluegill sunfish selecting larger vs. smaller crustaceansBluegill sunfish selecting larger vs. smaller crustaceans Mule deer feeding in open areas vs. forest edgesMule deer feeding in open areas vs. forest edges

Mating Behavior & Mate choiceMating Behavior & Mate choice Mating relationshipsMating relationships

Promiscuous- no pair bondsPromiscuous- no pair bonds Monogamous- single pair bond; no dimorphismMonogamous- single pair bond; no dimorphism Polygamous- sexual dimorphismPolygamous- sexual dimorphism

Polygyny- one male mating with several females; male Polygyny- one male mating with several females; male ornamentedornamented

Polyandry- single female mating with several males; female Polyandry- single female mating with several males; female ornamentedornamented

Need for parental care & certainty of paternity influence Need for parental care & certainty of paternity influence mating behavior mating behavior

Sexual selection & mate choiceSexual selection & mate choice Intersexual selectionIntersexual selection

Female preference for a male mating behavior or Female preference for a male mating behavior or anatomy influences that behavior or anatomical anatomy influences that behavior or anatomical structure’s rate of occurrencestructure’s rate of occurrence

Female prefer traits that signal male quality/healthFemale prefer traits that signal male quality/health Intrasexual selectionIntrasexual selection

Male competition for matesMale competition for mates Agnostic behavior- ritualized contest that determines Agnostic behavior- ritualized contest that determines

which male gains access to the resourcewhich male gains access to the resource Game Theory- Game Theory-

Different strategies effectiveness may vary based on Different strategies effectiveness may vary based on environment & strategies of other individualsenvironment & strategies of other individuals

Ex. Ispod Ex. Ispod Paracerceis sculptaParacerceis sculpta alpha, beta, & gamma alpha, beta, & gamma males; orange, yellow, & blue throat lizardsmales; orange, yellow, & blue throat lizards

Social Behavior & altruismSocial Behavior & altruism ““Selfish” behavior can be explained by natural Selfish” behavior can be explained by natural

selectionselection Altruism: selflessness; animal behaves in such a way Altruism: selflessness; animal behaves in such a way

that decreases its own fitness but increases the fitness that decreases its own fitness but increases the fitness of others in the populationof others in the population

Examples:Examples: Belding’s ground squirrel’s alarm callBelding’s ground squirrel’s alarm call Worker bee sterility; sting & dieWorker bee sterility; sting & die Naked mole rats protecting queen & kingsNaked mole rats protecting queen & kings

Inclusive fitness: total effect an individual has on Inclusive fitness: total effect an individual has on proliferating its genes through its own offspring or proliferating its genes through its own offspring or through a relatives offspringthrough a relatives offspring

rB>C favors altruistic behavior where:rB>C favors altruistic behavior where: r= coefficient of relatednessr= coefficient of relatedness B= benefit to the altruistic behavior (average # B= benefit to the altruistic behavior (average #

offspring that will be produced as a result)offspring that will be produced as a result) C= cost of altruistic behavior (average # of offspring C= cost of altruistic behavior (average # of offspring

that will not be produced as a result)that will not be produced as a result)

Kin selectionKin selection Individual acts to enhance the reproductive success of Individual acts to enhance the reproductive success of

relativesrelatives improves the chance that genes the same as his/her improves the chance that genes the same as his/her

own are passed onown are passed on Reciprocal altruismReciprocal altruism

Altruistic individual aids a non-relative with “hope” that Altruistic individual aids a non-relative with “hope” that the favor will be returned in the futurethe favor will be returned in the future

Found most often in highly social species in which Found most often in highly social species in which “cheating” would lead to negative consequences“cheating” would lead to negative consequences

““tit for tat”tit for tat”

Social Learning Social Learning Learning through observing othersLearning through observing others Culture: system of information transfer Culture: system of information transfer

through social learning or teaching of through social learning or teaching of individuals in a populationindividuals in a population

Example: Vervet monkey alarm callsExample: Vervet monkey alarm calls Sociobiology: study of human culture & its Sociobiology: study of human culture & its

relationship to evolutionary biologyrelationship to evolutionary biology