Cultural transmission of enemy recognition: one function of mobbing

Arranged blackbirds in adjacent cages so that a "teacher" bird could see a stuffed owl while an "observer" bird, seeing only the teacher, was shown a harmless object — a honeyeater, and in some trials a plastic bottle. The observer therefore saw mobbing directed at what it believed was the harmless object. Observers were then themselves used as teachers for further birds.

Studied in

Turdus merula

Sample size

blackbirds in a paired-cage apparatus with chained transmission

Observer birds began mobbing the harmless object, and passed that response on to further birds through a chain of several individuals, with the acquired response persisting through the transmission chain.

• Captive birds in an artificial apparatus, and the transmission chain is shorter than a real population.
• Shows that a false association can propagate without establishing how commonly this happens in the wild.

• Teaching blackbirds to mob a bottle

  Do birds inherit knowledge of what a predator looks like, or learn it from each other — and if they learn it, can they learn something false?

• Mobbing

  Predator recognition is partly learned by watching. Blackbirds shown another bird mobbing a harmless object began mobbing it themselves — and passed the mistake along a chain of further birds.