exam I motor strategies mate calling in crickets

song production by s song recognition by s sender-receiver matching summary

PART 3: MOTOR STRATEGIES#11: MATE CALLING IN CRICKETS I

SENSORY INPUT MOTOR OUTPUT

VISION

OLFACTION

GUSTATION

AUDITION

MOTIVATION

COURT

FORAGE

ATTACK

ESCAPE

FREEZE

CEN

TRA

LIN

TEGR

ATIO

N

MOTOR STRATEGIES

SENSORY INPUT MOTOR OUTPUT

VISION

OLFACTION

GUSTATION

AUDITION

MOTIVATION

COURT

FORAGE

ATTACK

ESCAPE

FREEZE

CEN

TRA

LIN

TEGR

ATIO

N

MOTOR STRATEGIES

SENSORY INPUT MOTOR OUTPUT

VISION

OLFACTION

GUSTATION

AUDITION

MOTIVATION

COURT

FORAGE

ATTACK

ESCAPE

FREEZE

CEN

TRA

LIN

TEGR

ATIO

N

MOTOR STRATEGIES

complex activity, requires

eg, coordinated operation of limbs

often rapid & appropriate responses to environmental signals

sensory-motor interface... behavior itself changes requirements of subsequent behavior

MOTOR STRATEGIES

song production by s only...

innate recognition by s...

innate attraction by s

s navigate s... courtship

stereotypic song

many species... many different songs

MATE CALLING IN CRICKETS

~ 2600 modern cricket species

most work on 3 related temperate latitude families: bush crickets (Tettigoniidae) field crickets (Gryllidae) mole crickets (Gryllotalpidae)

most nocturnal

high predation... many predators, avoid by hiding, freezing, burrowing, fleeing, camouflage short calls ~ ventriloquism... hard to locate

MATE CALLING IN CRICKETS

song production in s by scraping wings together

several types of song calling song courtship song aggressive song

MATE CALLING IN CRICKETS

song production in s by scraping wings together

several types of song calling song

response = positive phonotaxis call & remain stationary... attract single call & move... attract many s amplify & direct call using hollow trees, burrows

courtship song aggressive song

MATE CALLING IN CRICKETS

song production in s by scraping wings together

several types of song calling song courtship song

1 of many signals (olfactory, visual, tactile) aggressive song

MATE CALLING IN CRICKETS

song production in s by scraping wings together

several types of song calling song courtship song aggressive song

establish territory threaten impending aggression

MATE CALLING IN CRICKETS

several types of song

1st…how NOT to study cricket songs…

calling song…

courtship song

aggressive song…

establish territory

threaten impending aggression

MATE CALLING IN CRICKETS

calling by wing scissor motion = stridulation

file & scraper on wings

sound ~ comb

chirps & syllables

sonogram... amplify...

SONG PRODUCTION BY s

oscillogram cycles

carrier frequency 5 kHz 1 scraper tooth

pulses = syllables 1 stridulation

chirps & trills sequences

SONG PRODUCTION BY s

cricket CNS

chain of ganglia = functional aggregates of neurons

linked by paired connectives

brain (3 fused) sensory input

subeosphageal ganglion

thoracic ganglia (3)

abdominal ganglia (?)

HEAD

SONG PRODUCTION BY s

meso- & metathoracic ganglia

motor neurons innervate wing elevator muscles wing depressor muscles

SONG PRODUCTION CIRCUITRY

meso- & metathoracic ganglia motor neurons innervate

wing elevator muscles wing depressor muscles

observe a coordinated sequence of events…

record from motoneuron muscle... EMG

electromyogram

SONG PRODUCTION CIRCUITRY

correlate with tegmen movement muscle contraction sound ... closing only

note timing of events oscillating pattern reciprocal output to antagonistic muscles typical rhythmic motor

activity... eg ,walking

SONG PRODUCTION CIRCUITRY

interneuron spikes

motoneuron spikes

thoracic ganglia contain central pattern generator

inhibition (C)

activity (B)

correlate calls (A)

SONG PRODUCTION CIRCUITRY

central pattern generator (CPG) call “machinery”

brain call “decision”... from 3 experiments: focal stimulation in head

call & courtship songs stimulate cervical connective (in “neck”)

call & courtship songs cut off head... stimulate individual neurons in cervical connective...

call, courtship & aggression single neurons encode each type of trigger

TRIGGERING A SONG

central pattern generator (CPG) call “machinery”

brain call “decision” signals not ~ timing

of calls, only onset

TRIGGERING A SONG

brain / cervical connective stimulation shows that...

1. behavior onset but not pattern timing ~ stimulation descending signals need patterning from CPG

2. stimulus freq. ~ rate of chirping only rate encoded by brain

3. stimulus freq. or strength transition from call courtship or aggression weakest trigger call

TRIGGERING A SONG

brain / cervical connective stimulation shows that...

4. duration of brain stimulus ~ duration of call constant brain stimulus required for call

5. some stimulation call suppression... stimulus off resumed calling more intense, often courtship, postinhibitory rebound ~ song courtship in nature

TRIGGERING A SONG

song & response studied for > 200 yrs

how do s recognize song ? navigate s ... phonotaxis ?

can test for hrs distance constantnever “”

many versions of device... different questions

SONG RECOGNITION BY s

walks toward artificial call

zigzag pattern

oscillations 60° ~ direct line to source

SONG RECOGNITION BY s

what song features attract s ?

computer-constructed songs played s

varied components syllable rate syllable duration chirp rate # syllables / chirp duty cycle / chirp

SONG RECOGNITION BY s

what song features attract s ?

computer-constructed songs played s

varied components syllable rate

30 / s others not critical

SONG RECOGNITION BY s

how does the first recognize the song ? localize the song ?

2 tympanic membranes ~ 60 auditory receptor cells auditory neurons auditory nerve CNS

(prothoracic ganglion) associated with trachea

ears on forelegs

SONG RECOGNITION & LOCALIZATION

tracheal tubes = insect “lungs”

connect tympanum outside via spiracles

sound via 2 routes direct indirect

distance ½ wave pull / push

SONG RECOGNITION & LOCALIZATION

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