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
Bird Island, Seychelles Bird Island, Seychelles Bird Island is the northernmost island in the Seychelles archipelago, 100 km from Mahe. The 0.94 km coral island is known for its birdlife, including sooty terns, fairy terns and common noddies, and for hawksbill and green turtles. It is now a private resort with 26 bungalows. It also contains a small weather station and a small landing strip Bird Island Airport which connects the island with Mahe. Bird Island used to be known as "Île aux Vaches" due to the numerous dugongs (sea cows) that lived in nearby waters. Between 1896 and 1906, 17,000 tons of