communication Flashcards
communication
an action (signal) by 1 org (sender) that alters the probability of B occurring in another org (receiver) in a manner that is adaptive to either 1 or both parts
true communication
should benefit both sender & receiver
signal: info sent to reveiver with the goal of altering receiver’s B
* intended to affect B
* primary fxs contribute to fitness:
1. advertisement : sexual receptivity & food availibility
2. arousal: predator warning or dominance calls
3. identification: parent-offspring or dominant-subordinate
types of signals
discrete: on/off, yes/no
- little variability in intensity or duration
- ex: sows’ “statue stand” in estrus
- ex: ear position forward, side, or back
graded: variable in intensity & duration
- much more info in the quality of signal
- nuanced
- based on arousal or motivation of sender
- gradual, builds up
- collective visual & auditory info sent
- ex: aggressive signals in dogs: ears back ➔ teeth bared ➔ growl
dishonest communication
does not benefit 1 or both parties
cue: info from sender to receiver without goal of altering receiver’s B
* unintentional, accidental
* ex: mouse making crunching noises that owl hers
sensory modalities
- visual
- auditory
- olfactory
visual communication
- most often used by species active in daylight
- body posture
- facial expression
-
movement
- ex: waggle dance in honeybees: duration & direction of waggle communicates info RE food location
-
gesture
- ex: chimpanzees = diurnal species: 66 gestures w/ 19 meanings
- ex: panamanian golden frog = earless ➔ handwaving as warning/dominance assertion
-
light & color
- reception range for receiver = very important
- anatomy = important determinant for modality: shape, size, placement, & quality of eyes influence species’ use of visual communication
visual anatomy
retina: back of eye, contains photoreceptors
* rods surround cones: rods outer, cones inner
* rods: low light, black/gray/white, movement & fuzzy images ➔ contrast & movement
* ex: cats’ retinas have more rods than cones
* tapetum lucidum: area that bounces light around repeatedly to be reabsorbed (like mirror)
* pupils enlarge in dark ➔ can bring in much more light
* cones: bright light, color spectrum, sharp images ➔ color & detail
* ex: primates = tri-chromatic: 3 cones: blue, green, & red
* ex: other mammals = dichromatic: dogs, pigs, cattle, sheep, goats, horses have no green cones, deer have no red cones ➞ no evolutionary need
stereoscopic vision: location of eyes on head determines field of view & depth perception
* predators have binocular vision: both eyes see same thing at slightly diff angles
* forward-facing eyes
* ↑ depth perception
* narrowing field of view
* more focus on target
* prey have monocular vision: eyes can see diff things at diff angles
* eyes on side of head
* larger field of view ➞ can monitor all surrounding & run from predators
* wider range of threat-detection
auditory communication
-
sound production: terrestrial vertebrates use respiratory system to create sounds
- larynx in mammals or syrinx in birds tightens or loosens like releasing air from a balloon
- ex: dolphins don’t make sounds with their mouths
-
sound reception: sound waves create pressure in inner ear & transduced into electrical signals ➞ detection
- need ear lobe (pinna) & 2 ears to localize sound source based on diff times it hits each ear**
- hearing reception range (Hz): rats giggle when tickled ➞ info rats communicate cannot be picked up by receiver
must have appropriate anatomy to effectively communicate with auditory
olfactory communication
the distance from the scent to the original sender when the receiver receives the signal
- volatile: disseminated in air as vapor
- non-volatile: disseminated through oil/touch
- chemical signals:
- urine/feces
- anal sacs
- saliva
- sebaceous (oil) glands
- chin glands (rabbits, cats)
- musk glands (goat)
- inner-digit glands (ungulates)
- mammary glands (ungluates)
- primates have poor olfactory capabilities
- cattle/swine: urine = stress
- sheep: placenta = offspring identification
- swine: saliva = ovulation
- horse: urine = ovulation
olfactory communication in swine
- olfactory anatomy:
1. vomeronasal organ
2. nasal cavity
3. olfactory bulb - face-to-face chewing aka “chewing” air to smell
- for indiv verification/identification
- to assess challanger & assert dominance ➞ subordinate backs down
- sows can establish dominance hierarchy when blindfolded
- piglets can discriminate mother’s odors from strangers w/in a few days
efficiency of communication
i.e. is this the best signal to get info across
* depends on:
* quality of signal
* envir degradation ➞ could interrupt communication flow
* sensitivity of receiver
* attentiveness of receiver (i.e. headphones, facing away, etc.)
efficiency of communication
i.e. is this the best signal to get info across
* depends on:
* quality of signal
* envir degradation ➞ could interrupt communication flow
* ex: smoke/fog air ➞ auditory = better
* sensitivity of receiver
* attentiveness of receiver (i.e. headphones, facing away, etc.)
efficiency of modality
-
range: distance btwn sender & receiver to process signal
* short, med, long
* visual signals for dom species ahve a maximum efficiency for med range b/c of monocular vision -
transmission rate: how quickly the signal travels from sender to receiver
* slow, med, fast
* auditory signals = immediate -
flow around barriers: if signal would reach receiver if block btwn sender/receiver
* yes/no
* visual = no, auditory = yes -
fadeout time: how quickly signal goes away once sender stops transmitting signal
* fast, med, slow -
locate sender
* easy, med, hard
visual:
max range
transmission rate
flow around barrier
fadeout time
locate sender
max range: short & medium (max)
transmission rate: fast
flow around barrier: no
fadeout time: fast
locate sender: easy
auditory
max range
transmission rate
flow around barrier
fadeout time
locate sender
max range: long
transmission rate: fast
flow around barrier: yes
fadeout time: fast
locate sender: medium
