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CommunicatioCommunicationnChapter 12Chapter 12

Photo Copyright R. Hays Cummins

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CommunicatioCommunicationn

What is communication?What is communication? Types (traits vs. behaviours), classificationTypes (traits vs. behaviours), classification

How signals convey meaningHow signals convey meaning Channels of communication (methods)Channels of communication (methods) Functions of communication (purposes)Functions of communication (purposes) Complex Communication (bee dance)Complex Communication (bee dance)

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DefinitionDefinition

Types of CommunicationTypes of Communication

States/States/TraitsTraits

Behaviours Behaviours (‘signals’)(‘signals’)

What is What is Communication?Communication?

How is Communication Classified?How is Communication Classified?

Categories of Categories of Interaction (Wiley)Interaction (Wiley) Other viewsOther views

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What Is Communication?What Is Communication?

In biology, defined as: In biology, defined as: The The transfer of informationtransfer of information from one from one

molecule, cell, or organism to another, molecule, cell, or organism to another, as by chemical or electrical signals or by as by chemical or electrical signals or by behaviours. (www.dictionary.com)behaviours. (www.dictionary.com)

All communication involves a All communication involves a “sender” and a “receiver”“sender” and a “receiver”

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Biological CommunicationBiological Communication

Signal: Signal: The physical form in which a The physical form in which a message is coded;message is coded; any behaviour any behaviour pattern that communicates somethingpattern that communicates something Discrete vs. GradedDiscrete vs. Graded DiscreteDiscrete: “All or none” (e.g., FAPs) : “All or none” (e.g., FAPs) GradedGraded: Varying in intensity and/or : Varying in intensity and/or

frequency; provides info about the frequency; provides info about the strength of stimulus (e.gstrength of stimulus (e.g., Betta ., Betta splendenssplendens display) display)

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Increasing intensity

Discrete signal (ear position) Discrete signal (ear position)

Graded signal (mouth)Graded signal (mouth)

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Biological CommunicationBiological CommunicationDisplays areDisplays are one type of signal one type of signal

Display: Display: Any behaviour pattern Any behaviour pattern especially especially adapted adapted (i.e., modified (i.e., modified through evolution) in physical form or through evolution) in physical form or frequency to function as a social frequency to function as a social signal in communicationsignal in communication

e.g., spruce grouse males beating wings on air e.g., spruce grouse males beating wings on air

e.g., male dominance mounting in dogse.g., male dominance mounting in dogs

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Two male Two male Betta splendensBetta splendens showing fin flare and showing fin flare and operculum (gill) flareoperculum (gill) flare

Communicates willingness to fight; allows Communicates willingness to fight; allows assessment of opponent without combat/injuryassessment of opponent without combat/injury

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Wiley (Wiley (19831983): Categories of ): Categories of InteractionsInteractions

Terms used to describe interactions, depending Terms used to describe interactions, depending on the value of the info to sender and receiveron the value of the info to sender and receiver

Value of info to Value of info to SENDER:SENDER:

positivepositive zero (negative)zero (negative)

positivepositive ““True True communication”communication”

““Manipulation” Manipulation” (“deceit”)(“deceit”)

zero (negative)zero (negative) ““Eavesdropping” Eavesdropping” (“exploitation”)(“exploitation”)

““Ignoring” Ignoring” (“spite”)(“spite”)

Value of info to RECEIVER

++//++++//0 0 ++//--

00//0 0 --//--00//++--//++

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Biological CommunicationBiological CommunicationHow to classify/define communication?How to classify/define communication? ValueValue of information to each participant of information to each participant

Cost & Benefit AnalysisCost & Benefit Analysis• Both benefit = Both benefit = true true communicationcommunication; ;

male bird song during male bird song during mating seasonmating season

• Sender benefits, receiver is Sender benefits, receiver is unaffected or harmed = unaffected or harmed = deceit or manipulationdeceit or manipulation; e.g., ; e.g., killdeer performing “broken killdeer performing “broken wing display”wing display”

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Biological CommunicationBiological Communication DeceitDeceit

Interspecific deceit more Interspecific deceit more commoncommon

predator-prey predator-prey relationshipsrelationships

Aquatic predators that Aquatic predators that attract prey using attract prey using lures that look like lures that look like insectsinsects

Intraspecific “deceit” Intraspecific “deceit” unlikely to spread in a unlikely to spread in a population, except…population, except…

® Disney, Finding Nemo

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Categories of InteractionsCategories of Interactions

Sender benefits, receiver Sender benefits, receiver is harmed (+/-): is harmed (+/-):

DeceitDeceit Another example:Another example:

“ “femme fatale” femme fatale” fireflies – fireflies – females pretend to be females pretend to be receptive, attract and receptive, attract and consume males of consume males of another speciesanother species

http://www.ebertfest.com/two/grave_fireflies_bluebat.jpg

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Biological CommunicationBiological Communication

Value of information to each? Cont’dValue of information to each? Cont’d Sender unaffected or harmed, receiver Sender unaffected or harmed, receiver

benefits = benefits = exploitation or eavesdroppingexploitation or eavesdropping; ; mouse rustles grass as running, allowing owl mouse rustles grass as running, allowing owl

to hear it, catch it & eat it to hear it, catch it & eat it Neither benefit, both may be harmed = Neither benefit, both may be harmed =

ignoring or spiteignoring or spite; ; a bird ignores the cryptic colouration of a a bird ignores the cryptic colouration of a

moth and tries to eat it moth and tries to eat it Monarch ButterflyMonarch Butterfly

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Biological CommunicationBiological Communication Other ways to view Other ways to view

communication:communication: Communication need not benefit Communication need not benefit

both sender and receiver since both sender and receiver since natural selection operates natural selection operates mainly at the level of the mainly at the level of the individual (Dawkins & Krebs); individual (Dawkins & Krebs);

Displays evolve to “waste” a Displays evolve to “waste” a minimum of energy of sender…minimum of energy of sender… persuadepersuade the receiver, not the receiver, not “inform” (exaggeration and “inform” (exaggeration and redundancy of signals); redundancy of signals); roar of male lionroar of male lion

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Other ways to view communication:Other ways to view communication: Displays – have evolved to maximize the Displays – have evolved to maximize the

effectiveness of information transfer, to effectiveness of information transfer, to the benefit of both sender and receiverthe benefit of both sender and receiver

coevolution of signals; each species acts coevolution of signals; each species acts as a strong selection force on the other; as a strong selection force on the other; Problem: this definition cannot Problem: this definition cannot

encompass “lying”encompass “lying”

Biological CommunicationBiological Communication

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How Signals Convey How Signals Convey MeaningMeaning

Distance & Duration (signal type)Distance & Duration (signal type) Can travel far (e.g. scent), or operate Can travel far (e.g. scent), or operate

over short distances (e.g., visual signals)over short distances (e.g., visual signals)

Can be long-lasting (e.g., pheromones Can be long-lasting (e.g., pheromones entire breeding season) vs. short-term entire breeding season) vs. short-term (e.g., calls/ vocalizations)(e.g., calls/ vocalizations)

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How Signals Convey How Signals Convey MeaningMeaning

Individuals can increase information Individuals can increase information content of signals by… combining 2+ content of signals by… combining 2+ signals = csignals = compositeomposite signal signal Zebra: meaning of “open mouth” signal Zebra: meaning of “open mouth” signal

depends on ear position (forward = depends on ear position (forward = friendly; backwards = hostile)friendly; backwards = hostile)

……changing changing syntaxsyntax, or sequence of , or sequence of displays displays A before B is NOT = B before AA before B is NOT = B before A

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How Signals Convey How Signals Convey MeaningMeaning

Information in a signal can be Information in a signal can be context-dependent;context-dependent; E.g., “lion’s roar” : aggressive, E.g., “lion’s roar” : aggressive,

maintaining contact with pride maintaining contact with pride members, or indication to neighbours to members, or indication to neighbours to keep a good distancekeep a good distance

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Types of Communication Types of Communication (How can a message be (How can a message be

sent?)sent?) States or Traits: States or Traits:

Sign stimuli – Ch.’s 2 & 10Sign stimuli – Ch.’s 2 & 10 Aposematism & Batesian mimicry – Ch. Aposematism & Batesian mimicry – Ch.

1515 Indicator traits – Ch. 17 (to come)Indicator traits – Ch. 17 (to come)

Behaviours: (i.e., “does”)Behaviours: (i.e., “does”) Signals Signals

Some FAPsSome FAPs DisplaysDisplays

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Three-spined stickleback (Ch. 2, p. 15)Three-spined stickleback (Ch. 2, p. 15)

Enlarged belly of female = Enlarged belly of female = Sign stimulusSign stimulus (honest sign that female is ready to (honest sign that female is ready to spawn)spawn)

Sign StimuliSign Stimuli

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Sign StimuliSign Stimuli Not a behaviour, a Not a behaviour, a statestate (e.g., enlarged (e.g., enlarged

belly)belly) May provide info about physical state of May provide info about physical state of

bearerbearer NOTE: Not all sign stimuli convey NOTE: Not all sign stimuli convey

information, and not all FAPs act as signalsinformation, and not all FAPs act as signals E.g., egg retrieval in gullsE.g., egg retrieval in gulls If info is exchanged between conspecifics when If info is exchanged between conspecifics when

sign stimulus or FAP occurs = communicationsign stimulus or FAP occurs = communication

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Aposematism (warning Aposematism (warning colouration)colouration) Conspicuous markings of noxious Conspicuous markings of noxious

animals are easily recognizable and animals are easily recognizable and avoidable by predatorsavoidable by predators

Convey information about Convey information about unpalatabilityunpalatability

Batesian mimicry = Batesian mimicry = manipulation/deceit (lying)manipulation/deceit (lying)

http://www.rockleigh.org/Recreation/Images/Mammal/skunk.jpg

pinker.wjh.harvard.edu/ photos/santa_barbara_c...

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CommunicatioCommunicationn

What is communication?What is communication? Types (traits vs. behaviours), classificationTypes (traits vs. behaviours), classification

How signals convey meaningHow signals convey meaning Channels of communication (methods)Channels of communication (methods) Functions of communication (purposes)Functions of communication (purposes) Complex Communication (bee dance)Complex Communication (bee dance)

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Channels of Channels of CommunicationCommunication

OdourOdour Sound (ultrasonic, sonic, and Sound (ultrasonic, sonic, and

infrasonic)infrasonic) Seismic vibrationsSeismic vibrations TouchTouch Electric field Electric field VisualVisual

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Properties of Sensory Properties of Sensory ChannelsChannels

Range (distance covered) – Range (distance covered) – short to longshort to long Transmission rate (how long does it take to Transmission rate (how long does it take to

get from sender to receiver?) – get from sender to receiver?) – slow to fastslow to fast Can it travel around objects? – Can it travel around objects? – yes or noyes or no Can it be used at night? (Can it be used at night? (yes, no, or yes, no, or

sometimessometimes)) Fade-out time (how long does it last? – Fade-out time (how long does it last? – slow slow

to fastto fast)) Locate sender? (Locate sender? (easy to difficulteasy to difficult)) Cost to send signal (Cost to send signal (low to highlow to high)) Complexity of message (Complexity of message (low to highlow to high))

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Audition: Audition: PropertiesProperties

Auditory communicationAuditory communication Range?Range?

longlong Travels around objects?Travels around objects?

YesYes Useful at night?Useful at night?

YesYes Fade-out time?Fade-out time?

FastFast Cost to sender?Cost to sender?

HighHigh

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OdourOdour

Used by most species Used by most species (evolutionarily “old”)(evolutionarily “old”)

Usually involves Usually involves pheromones:pheromones: a species-specific odour cue a species-specific odour cue

released by animals that released by animals that influences the behaviour and/or influences the behaviour and/or physiology of conspecificsphysiology of conspecifics

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OdouOdourr

Functions:Functions: Group spacing – marking territoriesGroup spacing – marking territories Recognition – identifying conspecifics, Recognition – identifying conspecifics,

kin, individualskin, individuals Reproduction – attracting mates, Reproduction – attracting mates,

altering physiology (e.g., levels of sex altering physiology (e.g., levels of sex hormones)hormones)

Alarm – fear pheromone (e.g., inverts)Alarm – fear pheromone (e.g., inverts)

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OdourOdour Pheromones often Pheromones often

present in urine of present in urine of mammals (& anal glands) mammals (& anal glands)

Two types: Two types: primingpriming (generalized (generalized

response)response) signaling signaling (immediate (immediate

specific response)specific response) ““Flehmen” response Flehmen” response

(vomeronasal organ)(vomeronasal organ)

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Odour: PropertiesOdour: Properties long rangelong range slow transmission rateslow transmission rate travels around objectstravels around objects useful at nightuseful at night slow fade-out timeslow fade-out time low cost to senderlow cost to sender unable to locate senderunable to locate sender simple message onlysimple message only

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SoundSound

Can occur within or outside of human Can occur within or outside of human “umwelt” (~“umwelt” (~20-20,000 Hz)20-20,000 Hz) ultrasonic (high frequency - e.g., ultrasonic (high frequency - e.g.,

echolocation)echolocation) infrasonic (low frequency - e.g., African infrasonic (low frequency - e.g., African

elephant rumbles, whale song) elephant rumbles, whale song)

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SoundSound Can be produced by:Can be produced by:

a single organ a single organ ((vocalizations)vocalizations)

stridulationstridulation (e.g., (e.g., cricket “chirp”)cricket “chirp”)

other means (e.g., other means (e.g., drumming by Northern drumming by Northern Flickers/ woodpeckers)Flickers/ woodpeckers)

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SeismicSeismic Vibration Vibration

Substrate-borne vibrations detected Substrate-borne vibrations detected by animalsby animals White-lipped male frogs make thumps, White-lipped male frogs make thumps,

females extremely sensitive to vibrationsfemales extremely sensitive to vibrations Spiders catch prey by detecting vibrationsSpiders catch prey by detecting vibrations Male orb-weaving spiders “pluck” at web Male orb-weaving spiders “pluck” at web

to bring female out for matingto bring female out for mating

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Sound/Vibration Sound/Vibration PropertiesProperties

long rangelong range fast transmission ratefast transmission rate travels around objectstravels around objects useful at nightuseful at night fast fade-out timefast fade-out time high cost to senderhigh cost to sender may be able to locate may be able to locate

sendersender sound = complex message, sound = complex message,

vibration = simple messagevibration = simple message

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TouchTouch

Tactile communication (physical contact) Tactile communication (physical contact) Common in invertebrates: Antennae, tube Common in invertebrates: Antennae, tube

feet, etc. (also pick up chemical cues)feet, etc. (also pick up chemical cues) Vertebrate copulation Vertebrate copulation tactile stimulation tactile stimulation

elicits elicits lordosis responselordosis response in female mammals in female mammals Touch (e.g., vaginal stimulation) can induce Touch (e.g., vaginal stimulation) can induce

ovulation in some species (ovulation in some species (induced induced ovulatorsovulators))

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Touch: PropertiesTouch: Properties

short rangeshort range fast transmission ratefast transmission rate can’t travel around can’t travel around

objectsobjects useful at nightuseful at night fast fade-out timefast fade-out time low cost to senderlow cost to sender easy to locate sendereasy to locate sender Simple message onlySimple message only

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Visual CommunicationVisual Communication

Markings, patterns, colour require Markings, patterns, colour require vision vision

Mostly used by diurnal species (visual Mostly used by diurnal species (visual displays), e.g., aggressive displays of displays), e.g., aggressive displays of SFFSFF

Exception: firefliesException: fireflies species-specific flashing to attract mates species-specific flashing to attract mates

and during courtship and during courtship ““femme fatalesfemme fatales” of ” of Photuris versicolor Photuris versicolor

(deceit)(deceit)

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Vision: PropertiesVision: Properties medium rangemedium range fast transmission ratefast transmission rate can’t travel around can’t travel around

objectsobjects little use at nightlittle use at night fast fade-out timefast fade-out time cost to sender mediumcost to sender medium easy to locate sendereasy to locate sender allows complex messagesallows complex messages

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Electric FieldElectric Field

Some sharks and electric fish detect prey’s Some sharks and electric fish detect prey’s electric field using electroreceptorselectric field using electroreceptors

Strongly electric fish (e.g., electric eel) have Strongly electric fish (e.g., electric eel) have EODs (electric organ discharges of 100’s V)EODs (electric organ discharges of 100’s V)

Social communication possible by altering Social communication possible by altering wavelength/ pulse durationwavelength/ pulse duration

WhoZoo(http://whozoo.org)

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Electric Field: PropertiesElectric Field: Properties short rangeshort range fast transmission ratefast transmission rate travels around (and through) objectstravels around (and through) objects useful at night/in murky wateruseful at night/in murky water fast fade-out timefast fade-out time cost to sender variescost to sender varies easy to locate sendereasy to locate sender Simple message onlySimple message only

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Functions of CommunicationFunctions of Communication

1.1. Group spacing & coordinationGroup spacing & coordination2.2. RecognitionRecognition3.3. Reproduction (identifying/attracting Reproduction (identifying/attracting

mates)mates)4.4. Agonism and social statusAgonism and social status5.5. Alarm (warning)Alarm (warning)6.6. Finding foodFinding food7.7. Soliciting play Soliciting play 8.8. Giving & soliciting careGiving & soliciting care9.9. Synchronization of hatchingSynchronization of hatching

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Functions of CommunicationFunctions of Communication

Group Spacing & CoordinationGroup Spacing & Coordination Spacing signals of primates: Spacing signals of primates:

Distance-increasing (branch shaking)Distance-increasing (branch shaking) Distance-maintaining (dawn chorus)Distance-maintaining (dawn chorus) Distance-reducing (contact/lost calls)Distance-reducing (contact/lost calls) Proximity-maintaining (social grooming)Proximity-maintaining (social grooming)

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Functions of CommunicationFunctions of Communication

RecognitionRecognition Species RecognitionSpecies Recognition Neighbour RecognitionNeighbour Recognition Individual RecognitionIndividual Recognition Kin RecognitionKin Recognition

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Functions of CommunicationFunctions of Communication

ReproductionReproduction Courting displays, copulation- allow Courting displays, copulation- allow

assessments of species, physical assessments of species, physical condition, “quality” of matecondition, “quality” of mate

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Indicator Traits Indicator Traits ((Sexual Selection – Ch. 17Sexual Selection – Ch. 17))

Provide info to members Provide info to members of the opposite sex about of the opposite sex about the physical condition of the physical condition of the bearerthe bearer

Choosier sex (usually Choosier sex (usually females) show females) show preference for most preference for most extravagant traitsextravagant traits E.g., brightest colours, E.g., brightest colours,

largest antlers, largest antlers, longest tail feathers, longest tail feathers, etc. etc.

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Keeping signals HONEST:Keeping signals HONEST:

Zahavi & Zahavi’s “Handicap Principle”Zahavi & Zahavi’s “Handicap Principle”

If signals are If signals are costlycostly to produce to produce (peacock tail), they (peacock tail), they tend to be tend to be honest honest indicatorsindicators of of condition or ability condition or ability (i.e., in good health, (i.e., in good health, well-nourished and well-nourished and free of parasites)free of parasites)(sexual selection)(sexual selection)

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Functions of CommunicationFunctions of Communication

Social Status/ AgonismSocial Status/ Agonism Dominance/submissive displays- avoid Dominance/submissive displays- avoid

costly fightingcostly fighting Traits may also indicate social status Traits may also indicate social status

(bigger, stronger males perceived as (bigger, stronger males perceived as dominant) e.g., antler size in moosedominant) e.g., antler size in moose

wolves and dogs wolves and dogs

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Female Belding's ground squirrel (Spermophilus beldingi) emitting an alarm call. (Sherman)

•Alarm calls are given Alarm calls are given to warn other to warn other individuals about the individuals about the presence of a nearby presence of a nearby predator and are predator and are usually directed toward usually directed toward close kin.close kin.

•giving an alarm call giving an alarm call increases the chance increases the chance that the predator will that the predator will attack the callerattack the caller

Functions of CommunicationFunctions of CommunicationAlarmAlarm

Altruism or Altruism or Selfishness?Selfishness?

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Functions of CommunicationFunctions of Communication AlarmAlarm

Vervet monkeys: Seyfarth & CheneyVervet monkeys: Seyfarth & Cheney ““semantics”- different calls for different semantics”- different calls for different

predators (avian, ground)predators (avian, ground) Pheromones as chemical alarm Pheromones as chemical alarm

substancessubstances inverts; mammalsinverts; mammals Sea urchins steer clear Sea urchins steer clear of an area where a urchin of an area where a urchin has just been crushedhas just been crushed

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Functions of CommunicationFunctions of Communication Finding FoodFinding Food

““Information Centre Hypothesis”Information Centre Hypothesis” colonial organisms colonial organisms

(e.g., (e.g., communally roosting weaver communally roosting weaver birdsbirds))

hunting packs hunting packs (African wild dogs)(African wild dogs)

Giving/Soliciting Care, PlayGiving/Soliciting Care, Play; ; Synchronization of Synchronization of

HatchingHatching (precocial birds – (precocial birds – vocalize prior to hatching)vocalize prior to hatching)

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Evolution of DisplaysEvolution of Displays

Communicative displays are believed Communicative displays are believed to have evolved from to have evolved from noncommunicative behaviours through noncommunicative behaviours through the process of the process of ritualizationritualization::

Ritualization = Evolutionary process by Ritualization = Evolutionary process by which behaviour patterns become which behaviour patterns become modified to serve as communication modified to serve as communication signals.signals.

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Ritualization (example)Ritualization (example)

• Food calling behaviour still seen in Food calling behaviour still seen in roosters may be evolutionary origin roosters may be evolutionary origin of courtship display seen in peacocksof courtship display seen in peacocks

• i.e., peacocks’ ancestors may have i.e., peacocks’ ancestors may have performed food-calling behaviour, performed food-calling behaviour, which became which became ritualizedritualized into into bow/feather spread display presently bow/feather spread display presently usedused

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Evolution of DisplaysEvolution of Displays ““freezing” of movement freezing” of movement

into posturesinto postures Stereotyping of behaviour Stereotyping of behaviour

(stays constant even under (stays constant even under different levels of different levels of motivation)motivation)

Development of Development of conspicuous body conspicuous body structures- enlarged claws structures- enlarged claws (fiddler crab), ornamental (fiddler crab), ornamental feathers (peacocks, male feathers (peacocks, male ducks), manes (lion), ducks), manes (lion), exaggerated fins (exaggerated fins (BettaBetta) )

Crested Auklet (I. Jones)

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Displays may have arisen Displays may have arisen from…from…

Intention movementsIntention movements - e.g., “powk” - e.g., “powk” calls of BL Kittiwakes -- gannetscalls of BL Kittiwakes -- gannets

OROR Displacement activitiesDisplacement activities- innate, - innate,

stereotypical responses to stimuli that stereotypical responses to stimuli that seem inappropriate to the situationseem inappropriate to the situation Some degree of Some degree of conflictconflict in organism’s in organism’s

motivation- e.g., strange female motivation- e.g., strange female approaches: is a sexual or agonstic approaches: is a sexual or agonstic response needed? response needed?

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Displacement ActivitiesDisplacement Activities Evolved into courtship display: During Evolved into courtship display: During

courtship, males may preen or touch courtship, males may preen or touch own feathers (sham preening)own feathers (sham preening)

Conspicuous feathers (sailfeathers) Conspicuous feathers (sailfeathers) may have evolved and are exposed may have evolved and are exposed during this behaviourduring this behaviour

www.feathersite.com

Mandarin Duck

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Receiver bias Receiver bias - the - the increased sensitivity of increased sensitivity of perceptual systems to perceptual systems to certain stimuli as a certain stimuli as a result of natural result of natural selectionselectionSuch biases may influence the evolution of Such biases may influence the evolution of

communicative displayscommunicative displaysE.g., insect feeds mostly on yellow E.g., insect feeds mostly on yellow flowers, adapted to be sensitive to yellow flowers, adapted to be sensitive to yellow in general, males with yellow are in general, males with yellow are preferred, and may exploit this to attract preferred, and may exploit this to attract femalesfemales

Other Other origins origins of displays:of displays:

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Complex CommunicationComplex Communication

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Honeybee communicative Honeybee communicative dancesdances

“Round Dance”

Food nearby; less detailed“Waggle Dance”

Food >200m away; more detailed

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Photo Caption: Diagram of the honeybee dance. (Credit: P. Kirk Visscher.)•Ceiling of hive = direction of sun (reference)

Angle of straight run (on vertical) = direction of food source relative to sun

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•direction and durationdirection and duration of the straight run is critical of the straight run is critical•antennae of hive members maintain contact with antennae of hive members maintain contact with the dancer and taste samples of regurgitated foodthe dancer and taste samples of regurgitated food