The Complexities of Communication in Animal Behavior
This overview explores the intricate framework of communication in the animal kingdom, emphasizing the role of information in reducing uncertainty and shaping fitness outcomes. Key concepts include the distinction between cues and signals, the importance of honest signaling, and the consequences of dishonesty, which can lead to communication breakdowns. Various communication modalities such as visual, acoustic, chemical, and electrical signaling are analyzed, alongside their evolutionary implications. The mechanisms behind sound production, transmission, and reception are also highlighted as crucial elements in understanding animal interactions.
The Complexities of Communication in Animal Behavior
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Presentation Transcript
The informational framework • Information reduces uncertainty • Response determines fitness outcome • Cues vs. signals • Deceit Environment Reception Production Based on Bradbury and Vehrencamp (1998)
Honest signaling • Senders and receivers often disagree on optimal response • Mate choice, contests, etc. • Pervasive dishonesty leads to communication breakdown • Only honest signals are stable
Maintaining honesty • Costs • Production • Maintenance • Vulnerability • Convention • Constraints • Index signals
Some properties of signals • Active space • Duty cycle • Locatability • Identification level • Modulation potential • Costs / constraints • Optimal signal design varies by function
Signal evolution • Sender precursors • Intention movements • Ritualization • Cues • Amplification • Principal of antithesis • Receiver precursors • Sensory drive • Sensory exploitation
Communication networks • Eavesdropping • Intraspecific • Black-capped chickadees • Interspecific • Gryllus and Ormea • Audience effects
Modalities • Visual • Acoustic • Chemical • Vibrational • Electrical • Multimodal
Sound I • Sounds are moving pressure waves • Amplitude = loudness • Frequency ≈ pitch = waves / second • Wavelength determines frequency (because speed is ~ constant) amplitude pressure wavelength time frequency is # of waves that pass each sec
Sound II • Waveform • Spectrum • Fourier transform • Sonogram Amplitude Frequency
Sound production • Vibration generator • Need for multiplier • Stridulatory organs • Larynx • Syrinx • Resonator • In anurans • In humans Goller and Larsen 1997 PNAS 94:14787-
Sound transmission • Air versus water • Degradation • Global attenuation • Frequency dependent attenuation • Reverberation Forest Lake
Acoustic adaptation open forested • Environment constrains signal structure • Global attenuation • Limits active space • Frequency dependent attenuation • Constrains use of high frequencies • Reverberation • Constrains use of rapid changes flycatchers wrens tanagers
Sound reception • Ears • Frequency response • Directionality • Signal to noise ratio • Evolution of urban bird songs
Light • The electromagnetic spectrum • Radiance, reflection and absorption
Visual signal production • Pigments • Carotenoids • Melanins • Structural colors • Rayleigh scattering • Mie scattering • Bioluminescence • Extended phenotype http://home.vicnet.net.au/~osch/Bower%20photo1.jpg
Visual signal reception • Contrast with background • Available light
Olfactory communication • Properties • Slow • Non-directional • Non-spectral • Volatility affects duty cycle, active space • Trail following ants • Territorial badgers
Electrical communication • Only in fish • Generate fields • Strongly / weakly electric fish • Pulse / wave fish • Social communication • Courtship “songs” • Range: 1m • Electrolocation • Range: 2-5 cm
Vibrational communication • Widespread and ancient • Limited range, bandwidth • Private • Recording • Geophones • Accelerometers • Laser Doppler vibometers • Playback • Shakers • Magnetic setups
Echolocation • Principals • Diversity • Birds • Cetations • Bats • In bats
