THE ANIMAL FILES

Common cuckoo

Cuculus canorus

One chick can sound like a whole hungry brood.

The common cuckoo relies on other birds to rear its young. A begging chick's rapid calls stimulate feeding, while adult plumage can resemble a sparrowhawk. Sound, appearance and host responses interact at different stages of this brood-parasitic life.[1]

Follow the evidence ↓
Common cuckoo
Image: GabrielBuissart · Commons · CC BY-SA 3.0
A host's nest
Host parents raise the cuckoo chick.[1]
A demanding voice
Rapid begging can resemble a brood's calls.[1]
A hawk-like outline
Barred underparts resemble a sparrowhawk's.[1]

A host's nest

A cuckoo chick can evict eggs or young from the host nest, pushing them over the edge with its back. The foster parents then supply food. Studies debate the evolutionary pressures behind eviction, so the behaviour should not be explained as conscious planning by a chick.[1]

A demanding voice

Experiments describe rapid begging calls that stimulate host care despite presenting only one visible gape. This is a signal that affects feeding responses, not a claim that the host literally counts several unseen birds.[1]

A hawk-like outline

Adult cuckoos have a slender form and barred underparts. Model experiments found that host responses change when the barred pattern is obscured, supporting a role for resemblance. Females also occur in grey and rufous forms, adding variation beyond the familiar grey male.[1]

A COMMON MIX-UP

Does the cuckoo chick consciously invent a trick?

The evidence concerns evolved signals and host responses, not demonstrated human-like planning.[1]

TRY A LITTLE REASONING

How can one visible chick elicit strong feeding effort?

Reveal the explanation

Its rapid begging supplies a powerful acoustic stimulus alongside the single open mouth.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Common cuckoo (cited revision)
  2. NCBI Taxonomy — Cuculus canorus

Last fact check:

One discovery leads to another

Common swiftA nest made with materials caught in mid-air.Apus apus ↗Andean condorA huge bird can travel on rising air.Vultur gryphus ↗Peregrine falconA hunting dive is not the same measurement as level flight.Falco peregrinus ↗