Destruction of Cuckoos' Eggs. icy 



the facts, is an argument for a large number of eggs 

 in a season ; for, granting this, there is no reason 

 why it should not have a dozen or twenty eggs a 

 season just as easily as five. Unlike birds that brood, 

 it has no temptation at a definite point to reject male 

 advances, and a vast body of fact goes to prove that 

 it does not : laying eggs soon after it arrives, in the 

 very beginning of May, and continuing to lay eggs up 

 to close on the 29th July, within a few days of its 

 leaving. The risk the eggs have to run is very great 

 — many must be lost, many are dropped in places 

 where they can't be hatched, no doubt, because the 

 hens have not found suitable nests ready for their 

 deposition. The young cuckoos, from the very long 

 period of their helplessness and inability to feed 

 themselves after fledging, must suffer greatly from 

 birds of prey and other causes. If Mr. Darwin could 

 speak thus of eggs of birds which go through the 

 normal process of nesting and brooding, how much 

 must it apply to the case of eggs of the cuckoo com- 

 mitted to the care of others or laid carelessly on open 

 spaces : 



" The real importance of a large number of eggs 

 or seeds is to make up for much destruction at some 

 period of life ; and this period, in the great majority 

 of cases, is an early one. . . If many eggs or 

 young are destroyed, many must be produced, or the 

 species will become extinct." ■■'■ 



Clearly, there is great destruction of cuckoos' eggs, 

 and, from Mr. Darwin's argument, there must be 

 many produced. Dr. Russel Wallace's idea of the 

 immense destruction of birds' eggs and young in 



* Origin of Species, p. 52. 



