Direct fitness benefits of group living in a complex cooperative society of carrion crows, Corvus corone corone

  title={Direct fitness benefits of group living in a complex cooperative society of carrion crows, Corvus corone corone
  author={Vittorio Baglione and J. Martin Marcos and Daniela Canestrari and Jan Ekman},
  journal={Animal Behaviour},
The social behaviour of carrion crows varies between populations. In northern Spain cooperatively breeding groups form through delayed natal dispersal and/or immigration of individuals (usually males) into the territory. In this population, carrion crows therefore breed as either unassisted pairs, pairs with nondispersing 1–2-year-old helpers (nondispersers), pairs with immigrant helpers or mixed groups (pairs with both immigrants and nondispersers). We used a microsatellite-based genotyping… 

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