82 THE SENSES OF ANIMALS 



I naturally wished to eliminate any possibility of "associa- 

 tion" ; and so, in order to make some kind of test, I procured 

 an exactly similar tin but without mealworms in it, and this 

 was placed in the same spot as the usual tin while the bird 

 was resting and unable to see what was going on. At the 

 appropriate time I put the young cuckoo near to the tin and 

 awaited events — nothing ever happened. If the proper tin 

 were substituted for the empty one, there was an immediate 

 reaction. 



Of course, even the human ear can detect the faint rustling 

 made by mealworms in a tin containing bran, but this cannot 

 be heard at a distance of — say — ten feet, but the cuckoo 

 would show signs of interest from a much greater distance — 

 at times it would fly right across the room to alight near 

 the tin. 



Another aspect of hearing in birds may be noted in those 

 species (and there are many) whose members have powers 

 of mimicry. Parrots, budgerigars and mynahs, to say nothing 

 of crows and starlings, are well known to be able to imitate 

 the human voice and whistling, and also mechanical sounds. 

 To do this the birds in question must not only be able to 

 hear the greatly varying sounds clearly, they must be able 

 to remember them; and though the fascinating question of 

 memory in animals is not within the scope of this book, the 

 performances of good bird mimics do go to show the accuracy 

 with which the sounds are first heard and then learned and 

 stored away in that part of a bird's brain which is concerned 

 with memory. 



The great capacity for memorizing sounds possessed by 

 those birds which are known to mimic is most striking. I, 

 myself, have had several parrots which had a repertoire of 

 well over fifty words, noises, and tunes, while an African 

 Grey of mine totalled seventy diflferent words. I have also 

 had a mynah which could say more than a dozen words. 

 I am certain that there are far more imposing records than 

 these, and it is worth mentioning that the popular budgerigar 

 is probably better at learning or memorizing words and noises 

 than any other bird. 



Why some kinds of birds excel in this way and some do not 

 is, as far as I know, a mystery. There is little in common 



