A new study published online in the edition of the journal Biology Letters, reveals the quality of the avians of being competent enough to catch the shrewdness of birds like cuckoo, who try to fool these birds by hatching their eggs into the eggs of the avians.  

Avians use colour to identify the eggs of 'parasite' birds from their own and drive them out from their nests.

The birds were able to recognize and eject the eggs of the other bird when the researchers from Auckland University placed eggs of song thrushes painted in the same colour as of the eggs of the avians. The birds could identify the foreign eggs owing to the differences in the ultraviolet or short (blue) wavelength light between their own eggs and eggs of other bird.

According to lead researcher Dr Mark Hauber of the University of Auckland, birds with their different visual sense see ultraviolet wavelength which the human beings can not.