Summary
Honest signals are kept reliable by cost, as in the handicap principle.
In depth
Zahavi's handicap principle: costly signals are honest. Examples: peacock train, gazelle stotting. Signals can be arbitrary, indexical or conventional.
Signal reliability can be enforced by cost (handicaps), by physical constraints (indices such as body size and croak depth) or by social punishment. Receivers evolve skepticism toward cheap signals.
Example: a deep roar reliably indicates large size in red deer.
Signals evolve to influence receivers, so receivers need ways to trust them. Zahavi's handicap principle proposes that reliable signals are costly to produce, making them hard to fake: only high-quality individuals can afford them.
Honest signals include a peacock's tail, the stotting of gazelles which advertises fitness to predators, and the loud roars of red deer stags. Cheap signals can be reliable if interests align or if cheats are punished. Deception exists, as with mimicry and false alarm calls.
Example: brighter carotenoid colours in male finches reflect diet and health.
Key idea: signals are shaped by conflict and cooperation between signaller and receiver.
Frequently asked questions
What is Behavioural Ecology of Signalling?
Honest signals are kept reliable by cost, as in the handicap principle.
Which area of biology covers Behavioural Ecology of Signalling, and how advanced is it?
Behavioural Ecology of Signalling is one of the 53 topics in Animal Behaviour. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Communication, Altruism, Courtship.
Can you give an example of Behavioural Ecology of Signalling?
Stotting tells predators the gazelle is fit and not worth chasing.
What should I learn before Behavioural Ecology of Signalling?
Work through the Beginner topics in Animal Behaviour first, such as Animal Behaviour, Innate Behaviour, Learned Behaviour, then return to Behavioural Ecology of Signalling. Advanced topics assume the Intermediate vocabulary.
What topics are related to Behavioural Ecology of Signalling?
The closest topics to Behavioural Ecology of Signalling are Communication, Altruism, Courtship, Predator-Prey Arms Races. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Behavioural Ecology of Signalling?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Behavioural Ecology of Signalling. To practise the whole of Animal Behaviour, use the Animal Behaviour quiz.
How is Behavioural Ecology of Signalling different from Communication?
Behavioural Ecology of Signalling: Honest signals are kept reliable by cost, as in the handicap principle. Communication: Animals pass information using sound, scent, visual displays and touch. Read both side by side and note what each one explains.
How should I study Behavioural Ecology of Signalling step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Communication and explain the difference aloud. Finally, take the Animal Behaviour quiz and come back to this page for any question you miss.