Common cuckoo lay eggs that better imitate the host's eggs, the host species adapts and is more able to distinguish the cuckoo egg. A study of 248 common cuckoo and host eggs demonstrated that female cuckoos that parasitised common redstart nests laid eggs that matched better than those that targeted dunnocks. Spectroscopy was used to model how the host species saw the cuckoo eggs. Cuckoos that target dunnock nests lay white, brown-speckled eggs, in contrast to the dunnock's own blue eggs. The theory suggests that common redstarts have been parasitised by common cuckoos for longer, and so have evolved to be better
Common redpoll a further thirteen days. Common redpoll The common redpoll ("Acanthis flammea") is a species of bird in the finch family. It breeds somewhat further south than the Arctic redpoll, also in habitats with thickets or shrubs. The common redpoll was listed in 1758 by Linnaeus in the 10th edition of his "Systema Naturae" under the binomial name "Fringilla flammea". The current genus name "Acanthis" is from the Ancient Greek "akanthis", a name for a small now-unidentifiable bird, and "flammea" is the Latin for "flame-coloured". The common redpoll was previously placed in the genus "Carduelis". Molecular phylogenetic studies showed that the