322 HEREDITY AND SELECTION IN SOCIOLOGY 



case, owing to the serious disturbance of all social life caused by- 

 invasion ; nevertheless, Lapouge calculates that the death-rate, 

 which was 864,000 in 1869, rose to 1,046,000 in 1870, and attained 

 1,271,000 in 1871, falling again to the figure of 793,000 in 1872. 

 In this connection it is important to remember that large numbers 

 are of cardinal importance in race progress. In the first part of 

 this work we saw that, in order that the species may be maintained 

 at the high level necessary to its existence, it is essential that 

 natural selection shoidd have a vast number of individuals from 

 which to choose, a vast number of variations which can be sorted 

 out and selected. Thus, the species presenting the greatest 

 number of individual variations will be more exposed to the bene- 

 ficent action of natural selection, and consequently will have 

 more chance of being always adapted to its environment. Only, 

 however, if there are a sufficient number of individuals can a 

 sufficient number of variations be forthcoming to ensure the 

 necessary minuteness of adaptation. In the realm of nature there 

 are degrees of adaptation : some individuals are minutely adapted 

 in all their parts, others are less delicately adapted; but the 

 former are the fittest for survival and reproduction. And pre- 

 cisely these minutely adapted organisms cannot be produced 

 without a rich and abundant material for selection to act upon. 

 Let us take an example from the phenomenon of coadaptation. 

 If the antlers of the stag are to develop, it is necessary that the 

 muscles of the neck be developed, and also the muscles and sinews 

 of the legs, etc. That is to say that, if it be advantageous for 

 the stag that its antlers should develop beyond a given point, it 

 is necessary, in order that this development be effected, that the 

 muscles of the neck and of the fore-legs be previously or con- 

 temporaneously developed. Among the individuals composing the 

 species, the action of germinal selection may bring forth a number 

 of variations affecting different parts of the body; but only 

 those individuals who present variations in the sense of a develop- 

 ment of the muscles of the neck and fore-legs will be selected. 



