Transcript Communication

Communication
Transfer of information from a signaler to a
receiver (cooperative or non-cooperative?)
Any physiological, morphological or
behavioral display
Perceived by sense organs of another
animal
Must results in a change in receiver’s
behavior
Information
Identity - species, deme, kin, pairs,
individuals, neighbors, class or social
status
Ability or condition - contest, signal to
predator, potential to mate, ability to mate
Intention - aggression, submission,
soliciting care or play
Environment - alarm call, food
Kin recognition
Mechanism
Association
non-aggressive if reared
together, aggressive if
reared apart
Phenotype matching
MHC glycoprotein
Channels of communication
Selecting forces on the form
of signals
Species anatomy & physiology
Species behavior
Environment
Ecological constraints - frequency
window
Legitimate signalers/receivers
Intraspecific interaction
Signals between parents and offspring
Distress calls
Begging calls
Following commends
Aggressive signals
Defensive interaction
Warning signals (coral snake, bee, rattlesnake)
Feeding deterrent (monarch butterfly)
Aposematic coloration
Flower – Pollinator
Color, odor, shap
Illegitimate signalers
Misinformation
Batesian mimicry – harmless species that
mimic warning signals of dangerous
species
King snakes mimicking coral snake
Flies mimicking bees
Burrowing owls mimicking rattlesnakes
Batesian mimicry
Evolution 47:277-235, 1993
Coral snakes and their mimic
Question:
Do color pattern of coral snakes function as
warning signals?
Do even imprecise non-venomous mimics
experience reduced predation?
Warning coloration & mimicry
Experimental approach – plasticine replicas
Can be employed in large number
Retain evidence of predatory attack
Study conducted in Costa Rica
Replicas placed out on transect
inspect at regular intervals for “injuries”
Illegitimate signalers
Aggressive mimicry – animals that mimic
sexual signals of other animals to attract
those animals as prey
Fireflies, angler fish
Intraspecific deceit – animals that transfer
misinformation to members of own species
Bluff display
Nest parasites, e.g. brown-headed
cowbirds
Rove beetles lay eggs in ant nest
Mimic of cleaner wrasses
Illegitimate receivers
Interception of signals
E.g. tungara frog: whine-chuck
Bats are attracted to frog calls
Bats prefer whine-chuck to whine alone
Tendency of males to produce whine-alone
calls increase with intensity of predation
Evolution of maladaptive behavior
Novel environmental hypothesis –
change of environment
Sensory exploitation hypothesis
Cost << benefit
Risk of being exploited is very low
Response to signals has a clear adaptive
value
Mobbing calls vs. “seet” alarm calls in
great tit
Mobbing call – 4.5 kHz, easily located,
join mobbers in the harassment of their
mutual enemy (perched hawk)
Seet alarm call – 7-8 kHz, rapid
attenuation, warn mates and offspring
of possible danger (flying hawk)
Convergent evolution in the seet calls
An. Beh. 55:511-518, 1998
Red squirrels: 5 types of calls: rattle,
screech, growl, buzz, bark
1-4: territorial or agonistic, three types of
bark: seet, seet-bark, bark
Three types of predator: human, dog,
model or natural birds
Results: Bark when human or dog, seet
or seet-bark when birds
Sematic or referential information? Low
cross-taxon mistake may indicate
referential information
Complexity of environment and diversity
of escape response to different predator
may affect the evolution of alarm call
An. Beh. 55:529-536, 1998
Heterospecific alarm call
Yellow-bellied marmot and golden-mantled
ground squirrel respond to conspecific and
hetero-specific alarm call more than to wren calls
Responses: stop feeding, running, raise their head
and scanning
Maintain anti-predator and vigilance longer during
30-sec playback and post-playback periods
Sensory preference
Sensory exploitation hypothesis
Female preference evolves before male
traits
Coevolution hypothesis
Female preference evolves with male traits