INSTINCT 225 



tralian Jungle Fowl have been evolved? This bird 

 does not incubate its eggs but deposits them in a great 

 heap of decomposing organic matter, sometimes fif- 

 teen feet high and sixty feet in circumference, which 

 it piles up by throwing backwards with one foot while 

 it stands on the other. 



Each egg is deposited in a separate hole several 

 feet long in the mound, after which the hole is 

 filled with loose material and the egg left to incubate. 

 It is evident that this bird could not have abandoned 

 the usual method of incubation until its instinct 

 caused it to construct a tumulus of organic matter 

 sufficient for the purpose of incubation. It would 

 not be claimed that it did this suddenly, but gradual- 

 ly. It must have at first brought together sufficient 

 material to relieve it of part of the work of incuba- 

 tion, and the habit of doing this must have grown, 

 because it was useful, until it finally ceased incu- 

 bating its eggs. It also lost the instinct, common to 

 birds, of placing all of its eggs in close proximity 

 with each other, for it deposits but one egg in each 

 hole. 



The fact that these changes in its instincts and 

 habits are conceivable can only show the possibility 

 and not the probability that they have taken place. 

 It is conceivable that trees might become men, and 

 yet this does not even suggest the possibility of such 

 a change. 



The various instincts which cause animals to pro- 

 vide in advance for the young that they never see 

 nor recognize as their offspring cannot, I think, be 

 satisfactorily accounted for by evolution. 



Take, for example, the well-known beetle, which 

 prepares a ball of animal excretion in which it depos- 

 its an egg and then buries the ball in a deep hole 

 which it makes in the earth, where it is hatched, and 



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