 An experiment by the Australian zoologist A.D. Blest demonstrated that the more an eyespot resembled a real vertebrate eye in both colour and pattern , the more effective it was in scaring off insectivorous birds . In another experiment using peacock butterflies , Blest showed that when the conspicuous eyespots had been rubbed off , insectivorous birds ( yellow buntings ) were much less effectively frightened off , and therefore both the sudden appearance of colour , and the actual eyespot pattern , contribute to the effectiveness of the deimatic display . 
