430 THE WONDER OF LIFE 



of its actual mother's cluck. Even when thirsty it does 

 not recognize water as drinkable stuff, not even when it 

 walks through it. So unprejudiced is its tabula rasa of a 

 brain, that it will stuff its crop with worms of red worsted. 

 But the point is that it makes up for its paucity of instincts 

 by an extraordinarily rapid educability. And that is 

 what the parent-birds work with in educating their young 

 in the ordinary conditions of wild nature. 



As all Mammals except the primitive Monotremes are 

 viviparous, their exhibition of parental care is perhaps not 

 so striking as in the nest-building and brooding birds, but 

 it often reaches a high level. We have to remember the 

 often prolonged gestation the mother carrying, as it were, 

 a huge parasite within herself, the suckling of the young, 

 and it may be carrying them about, as in Marsupials and 

 Bats, the defence of the family, and their initiation into 

 the business of life. Some Mammals, such as monkeys, 

 have a prolonged infancy and a long gastric education on 

 milk ; others are quickly able to look after themselves. 

 We read that a giraffe is able to stand up in about twenty 

 minutes after birth, to run freely in a day or two, and to 

 nibble grass in three weeks. 



Chain of Parental Instincts. There are many unsolved 

 problems connected with parental care, but we think that 

 Professor F. H. Herrick has made many points clearer by his 

 conception of a chain or cycle of parental instincts, to 

 which we have already referred in connection with the 

 cuckoo (p. 320). The events in the cycle follow one 

 another with almost clock-like precision, but are always 

 liable to be influenced by intelligence. Normally they 

 form a harmonious series, and, what is very important, 

 there is an attunement a time-keeping between the 



