BIOL3046 Lecture Notes - Lecture 17: Short Songs, Lek Mating, Vasodilation
5 Jul 2018
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Department
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Animal Behaviour BIOL3046 460381099
Lecture 17: Communication and signalling.
Cue Unit of information collected by an individual. Example: Prey animals provide
cues to predators (not intentional) can be from CO2 and smelly feet
attracting mosquitos; Elephant belly rumble (continuous noise); Rattle snakes
can determine if chemical cues were successful in the past and use this for
the future.
Signal Information transmitted from source to receiver, to influence behaviour.
Deliberate attempts to communicate. Difficult to infer intentionality. Two
evolutionary pathways for the evolution of signals. 1. Based on the sender,
adapted from the behaviour or anatomical structure. Example: Adapted from
existing behaviour: characteristics of wolves to bare teeth before biting,
another wolf will do the same. Physiological responses: skin of turkey swells
during stress due to vasodilation or tamarin sticks up its hair in aggression.
Displacement activities: Animal may have conflicting decisions such as polar
bears have conflicting motivations to kill each other and to mate. 2. Based
on the receiver, exploits receiver’s sensory biases to detect information
better than others. Receiver has preference for a signal, maybe more
responsive to a form of stimulus. Example: Cuckoos displaces hosts young,
and young mimic sounds of an entire brood. Sounds as though itself is a nest
full of chicks, and parent can’t seem to help but feed the young. Baby
humans cry at an annoying frequency, and can’t be ignored.
Signal components Tactical components
• Clarity of the message, communication is effective. The most successful signals show
conspicuousness (stands out in background), stereotypy (all individuals in the species
display the same signal), redundancy (repetition of the same message to make sure it
gets across).
• Example: Singing humpback; Octopus loss of colour.
• The habitat helps determine which channel of communication a species will use.
• Acoustic adaptation hypothesis: Sounds attenuate and degrade in different
environments: In habitats with complex vegetation structure the songs are more
Document Summary
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