THE KEGULATION OF NUMBEKS 215 



of these customs is still more impressive ; for the observations 

 upon which we have to rely have for the greater part been made 

 after these races had been in contact with Europeans, and such 

 contact is followed by a diminution of these practices. 



One of the first changes brought about by this contact is 

 connected with the introduction of diseases previously unknown. 

 These diseases are often peculiarly fatal, causing a very high death- 

 rate, and it is clear that, unless the practices of abstention from 

 intercourse, abortion, and infanticide were largely abandoned, 

 the race would perish. There is no difficulty in understanding 

 how these practices would actually be abandoned soon after the 

 introduction of disease. The proximate causes of these practices 

 are largely, as we shall see, the difficulty of transporting many 

 young children and the undesirability of having more than one 

 child during the period of lactation. If disease began to carry off 

 many children, the immediate causes for these practices would 

 largely or entirely disappear and so would the customs themselves. 1 



Apart from the introduction of disease, the effect of contact is 

 in other ways to reduce the extent of these practices. Contact has 

 often resulted in warfare between aboriginal races and European 

 settlers as in Tasmania, Australia, and America, or as between 

 the Bushmen and the Boers. The largely increased death-rate 

 would, as in the case of disease, be followed by a diminution of the 

 extent of these practices. Further, under other conditions, as for 

 instance in Polynesia, the efforts of missionaries have long been 

 directed to putting a stop to these customs. 2 We may also 

 note that there is often a bias on the part of observers to under- 

 estimate the extent of the employment of infanticide and abortion. 

 Many observers are attracted by the races who come under their 

 notice and seem to think that these practices are incompatible 

 with the kindly nature or pleasant disposition of the people they 

 describe that in fact the attribution to them of such customs as 



1 Some authors have assumed without producing any evidence that these 

 practices especially infanticide have increased, if they have not been initiated, 

 after contact with Europeans. It is, therefore, of interest to note that according 

 to Rivers there is definite genealogical evidence from Tikopia of the disappearance 

 of infanticide (Melanesian Society, vol. i, p. 352). 



2 According to Neuhauss for instance, both abortion and infanticide were 

 formerly prevalent in parts of New Guinea where they are now rare owing to 

 missionary teaching. No accurate account has been given of these tribes in their 

 former state, and thus quite possibly a modern observer might well merely record 

 the practices as being rare ' a statement which would be misleading for our 

 present purpose but which is of the kind likely to be relied on by those who do not 

 admit the wide prevalence of these customs (Deutsch Neu-Guinea, vol i, p. 31). 



