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Animal BehaviorThis just in: Male lobsters mayurinate in the face of other males

Write down a question about thisbehavior

Today - Approaches to the studyof animal behavior1. The description of the behavior2a. The physiological basis of the

behavior2b. The neurological basis of the

behavior

3. The role of learning and instinct i nthe acquisition of a behavior

4. The evolutionary history of thebehavior in the species and itsrelatives

5. The adaptive significance of thebehavior

I. The five approaches tobehavior

What happens ?

1 . The description of thebehavior

I. The five approaches tobehavior

How does urination work ascommunication? Whatmachinery is involved?

2a. The physiological basis ofthe behavior

I. The five approaches tobehavior

How does urination work ascommunication? Whatmachinery is involved?

2a. The physiological basis ofthe behavior

2b. The neurological basis ofthe behavior

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I. The five approaches tobehavior

How does the behavior of urinatingon other males develop?

3. The role of learning and instinctin the acquisition of a behavior

I. The five approaches tobehavior

Why has this species of lobsterdeveloped this behavior?

4. The evolutionary history of thebehavior in the species and itsrelatives

I. The five approaches tobehavior

And the one you’ve all beenwaiting for… .

Why do male lobsters urinate onother males?

5. The adaptive significance ofthe behavior

Questions about behavior can becategorized into what and howquestions (proximate) and why(ultimate) questions

Proximate cause - an immediateunderlying cause, the mechanism

Ultimate cause - the evolutionaryreason for why something is theway it is. Can have adaptive andhistorical components.

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questions

What happens ?

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questions

What happens ? PROXIMATE

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Behavior can be approached usingboth what and how (proximate)and why (ultimate) questions

What happens ? PROXIMATE

How does urination work ascommunication? What machineryis involved?

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questions

What happens ? PROXIMATE

How does urination work ascommunication? What machineryis involved? PROXIMATE

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questionsWhat happens ? PROXIMATE

How does urination work ascommunication? What machinery isinvolved? PROXIMATE

How does the behavior of urinating onother males develop?

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questionsWhat happens ? PROXIMATE

How does urination work ascommunication? What machinery isinvolved? PROXIMATE

How does the behavior of urinating onother males develop? PROXIMATE

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questionsWhat happens ? PROXIMATE

How does urination work ascommunication? What machinery isinvolved? PROXIMATE

How does the behavior of urinating onother males develop? PROXIMATE

Why has this species of lobsterdeveloped this behavior?

Behavior can be approached usingboth what and how (proximate)and why (ultimate) questionsWhat happens ? PROXIMATE

How does urination work ascommunication? What machinery isinvolved? PROXIMATE

How does the behavior of urinating onother males develop? PROXIMATE

Why has this species of lobsterdeveloped this behavior? ULTIMATE

Why do male lobsters urinate on othermales?

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Behavior can be approached usingboth what and how (proximate)and why (ultimate) questionsWhat happens ? PROXIMATE

How does urination work ascommunication? What machinery isinvolved? PROXIMATE

How does the behavior of urinating onother males develop? PROXIMATE

Why has this species of lobsterdeveloped this behavior? ULTIMATE

Why do male lobsters urinate on othermales? ULTIMATE

Today - examples of studiesusing the different approaches

1. The description of the behavior - N oexample

2a. The physiological basis of thebehavior

2b. The neurological basis of thebehavior

3. The role of learning and instinct in theacquisition of a behavior

4. The evolutionary history of thebehavior in the species and its relatives

5. The adaptive significance of thebehavior - All of next lecture

2a. The physiological basis ofbehavior

Example: Aggression in mice:effects of female hormones inthe uterine environment

2a. The physiological basis ofbehavior

Example: Female hormones in theuterine environment of mouseembryosObservation: Malesdeveloping betweentwo females (OM)were exposed tomore female hormone,estradiol and less malehormone, testosteronethan males surroundedby two males (2M)

Estra

diol

inam

niot

ic fl

uid

Femalemales

2M OM

2a. The physiological basis of behavior

Example: Female hormones in theuterine environment of mouse embryos

Higher estradiol, lower testosteroneHigher testosterone, lower estradiol

0M male

2M male

2a. The physiological basis ofbehaviorExample: Female hormones in the

uterine environment of mouse embryos

Does the exposure of embryos todifferent concentrations ofsex hormones inthe uterus determine aspects of adultbehavior?

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2a. The physiological basis of behavior

Example: Hormones in the uterineenvironment of mouse embryos

Experimental design:Mice delivered by cesarean section

so position noted

2a. The physiological basis ofbehavior

Example: Hormones in the uterineenvironment of mouse embryos

Experimental designMice delivered by cesarean section

so position notedMales castrated and given

testosterone implants - why?

2a. The physiological basis ofbehavior

Example: Hormones in the uterineenvironment of mouse embryos

Experimental designMice delivered by cesarean section

so position notedMales castrated and given

testosterone implants - why?Experimenters measured

aggressiveness towards strangers

2a. The physiological basis ofbehaviorExample: Hormones in the uterine

environment of mouse embryos

Results:

Interpretation?

Perc

enta

ge a

ttack

ing

stra

nger

2MOM

2b. The neurological basis ofbehavior

Example: Moths evading bats

2b. The neurological basis ofbehavior

Example: Moths evading batsObservation: When bats approached,

moths were seen to change direction or engage in erratic flight. Could moths hear the bats approach?

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2b. The neurological basis of behavior

Example: Moths evading batsFound an ear on each

side of moth thorax -a tympanic membranewith 2 receptorneurons, A1 and A2 Ears

Tympanicmembrane A1 & A2

receptorcells

2b. The neurological basis ofbehavior

Example: Moths evading bats

Question: What information dothese two neurons receive andhow do they direct escape of themoth?

2b. The neurological basis ofbehavior

Example: Moths evading bats

Experimental design:Tethered live moths in a chamber

2b. The neurological basis ofbehavior

Example: Moths evading bats

Experimental design:Tethered live moths in a chamberPut electrodes in one of the

receptors

2b. The neurological basis ofbehavior

Example: Moths evading batsExperimental design:Tethered live moths in a chamberPut electrodes in one of the

receptorsExposed moths to bat-like sounds of

different intensity (loudness),frequency (pitch) and duration

2b. The neurological basis ofbehavior

Example: Moths evading bats

Experimental design:Tethered live moths in a chamberPut electrodes in one of the

receptorsExposed moths to sounds of

different intensity (loudness),frequency (pitch) and duration

Recorded the response of thereceptor

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2b. The neurological basis ofbehaviorExample: Moths evading batsA1 receptor:

A1 receptor

Lowintensity

Moderateintensity

Highintensity

2b. The neurological basis of behavior

Example: Moths evading batsA1 receptor: Graded response to

pulses of sound depending onintensity (loudness)

A1 receptor

Lowintensity

Moderateintensity

Highintensity

2b. The neurological basis ofbehavior

Example: Moths evading batsA1 receptor:Experimenters suggested that

differences in firing of the L and RA1 neuron would tell moth wherethe sound is coming from, allow itto move in opposite direction

2b. The neurological basis of behavior

Example: Moths evading batsA1 receptor:

Bat to oneside

Bat directlybehind

2b. The neurological basis ofbehavior

Example: Moths evading batsA2 receptor:

A2 receptor

Lowintensity

Moderateintensity

Highintensity

2b. The neurological basis ofbehavior

Example: Moths evading batsA2 receptor: Only responded to

high intensity (loud) bursts ofsound

A2 receptor

Lowintensity

Moderateintensity

Highintensity

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2b. The neurological basis of behavior

Example: Moths evading batsA2 receptor: Only responded to

high intensity (loud) bursts ofsound

Experimenters suggested that firingof this neuron may cause shutdown of central flight steeringmechanisms in brain, result in theerratic flight that moths exhibitwhen bats are very close

2b. The neurological basis of behavior

Moths evade bats by a very elegantand simple neurologicalmechanism

2 independent neurons

One for when the bat is far enoughaway that a simple change ofdirection will work

The other for situations whereimmediate evasive action isnecessary - when flight path is notpredictable, bats have difficultytracking moth flight

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Beewolf natural history

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding by beewolvesBeewolf natural history

How do they find their nest again?

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Hypothesis: When theyleave the nest, theymemorize locallandmarks… so theylearn to recognizethe spot

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3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Experiment 1: Experimentermixed up the local landmarks(stones, vegetation, etc.).

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Experiment 1: Experimentermixed up the local landmarks(stones, vegetation, etc.).

Results: Wasps took longer tofind nest entrance

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Another experiment?

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Experiment 2: Experimentercarefully moved all the locallandmarks to surround a spot ameter or so away

3. The role of learning and instinctin the acquisition of a behavior

Example: Nest finding bybeewolves

Experiment 2: Experimentercarefully moved all the locallandmarks to surround a spot ameter or so away

What result would you expect ifthe hypothesis was true?

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

What are the functions of courtshipbehavior?

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4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Observation: male pelagic shags(a type of cormorant) performthis courtship behavior:rapid-flutter wingwaving, whilehead is back,pointing straight up

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Hypothesis: Courtship behaviorin pelagic shag evolved fromless complex courtshipdisplays, and originated inflight intention movements

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Experiment?

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Experiment: Documentedcourtship behavior in relatedspecies

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Experiment: Documentedcourtship behavior in relatedspecies

Constructed cladogram basedon courtship behavior alone

4. The evolutionary history of thebehavior in the species and itsrelatives

Example: courtship behavior incormorants

Experiment: Documented courtshipbehavior in related species

Constructed cladogram based oncourtship behavior alone

Compared cladogram based onbehavior with cladogramconstructed from other evidence(here gene sequences)

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4. The evolutionary history of thebehavior in the species and its relatives

Example: courtship behavior incormorants

Experiment: Documented courtshipbehavior in related species

Constructed cladogram based oncourtship behavior alone

Compared cladogram based onbehavior with cladogramconstructed from other evidence(here gene sequences)

What did they predict?

4. The evolutionary history of thebehavior in the species and its relatives

Example: courtship behavior incormorants

Results

Pre-takeoff

Wing waveBoth wings

Rapid

4. The evolutionary history of thebehavior in the species and its relatives

Example: courtship behavior incormorants

Results

Good fitbetweenthe behav-

ioral andDNAsequence

cladogramPre-takeoff

Wing waveBoth wings

Rapid

Summary - the five approaches

1. The description of the behavior2a. The physiological basis of the

behavior2b. The neurological basis of the

behavior

3. The role of learning and instinct i nthe acquisition of a behavior

4. The evolutionary history of thebehavior in the species and itsrelatives

5. The adaptive significance of thebehavior - BEHAVIORAL ECOLOGY-next time!