How strong are eggs of the common cuckoo Cuculus canorus?

  title={How strong are eggs of the common cuckoo Cuculus canorus?},
  author={Jaroslav Picman and Marcel Honza},
  journal={Folia Zoologica},
  pages={20109.1 - 7}
Abstract. The common cuckoo Cuculus canorus is an obligate brood parasite that lays its eggs in the nests of small passerines. It has long been hypothesized that cuckoo eggs should be structurally stronger than host eggs or those of non-parasitic cuckoos to reduce chances of breakage during laying, to prevent accidental damage during incubation and/or to hinder their rejection through puncture ejection by the host. Therefore, we analysed selected characteristics of a sample of freshly laid eggs… 



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Great reed warblers in the authors' heavily parasitised population are capable of detecting brood parasitism in their clutch by identifying the parasitic egg, and the efficiency of this identification depends mainly on the mimicry of the foreign egg.

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Egg‐morphs and host preference in the common cuckoo (Cuculus canorus): an analysis of cuckoo and host eggs from European museum collections

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Cuckoos parasitising four sympatric species of Acrocephalus warblers in southern Moravia, Czech Republic showed a high level of parasitism, egg mimicry and breeding success, but the cuckoo chicks survived better in great reed warbler nests, resulting in a breeding success of 30.4%, as compared to 16.4% in nests of the reing warbler.

Are blackcaps current winners in the evolutionary struggle against the common cuckoo?

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