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
The Bird 'Grip' ever after. While the hero in these stories is normally aided by a talking animal, for it to be a ghost is unusual. This is the grateful dead, a common folklore motif, found also in "Fair Brow". The Bird 'Grip' The Bird 'Grip' is a Swedish fairy tale. Andrew Lang included it "The Pink Fairy Book". It is Aarne-Thompson type 550, the quest for the golden bird/firebird; other tales of this type include "The Golden Bird", "The Greek Princess and the Young Gardener", "How Ian Direach got the Blue Falcon", "The Nunda, Eater of People", and "Tsarevitch Ivan, the Fire