134 ANALYSIS Olf THE I^OUR PRINCIPLES (cONtlNUED). 



conditions in the environment that may have an effect in producing 

 divergence, he calls attention to the fact that the small isolated por- 

 tion of the species "is at once in a different position as regards its 

 own kind." Now, this is exactly what I mean when I say that the iso- 

 lation of a small portion has some effect in producing divergence, even 

 if the conditions outside of the species could be absolutely the same 

 as in the original habitat. Still further, as I have abundantly shown 

 in the paper reproduced in Appendix II, it is very possible that the 

 isolated portion will, early in its career, if not from the very first, be 

 subjected to new forms of selection, through the adoption of habits 

 of feeding that are wanting, or unusual, in the original habitat ; for a 

 rare habit in the original valley might become the predominant habit 

 in the colony that arises in the newly occupied valley, even if the envi- 

 ronments were absolutely the same. This form of selection I have 

 called active (or endonomic) selection. 



Indiscriminate success will arise in regard to any given habitude, 

 or form of acquired efficiency, when the attainment or the non-attain- 

 ment of the habitude has no effect on the success or influence of the 

 individual. Another form of indiscriminate influence may be intro- 

 duced by the indiscriminate slaughter of all but a few individuals 

 of a community, in which case the habits of the few remaining indi- 

 viduals will have great influence on the habits of the new community 

 arising through the multiplication of the few survivors. 



Indiscriminate partition arises whenever the occasion that brings a 

 number of individuals of a species together in a separate position does 

 not determine that they shall be of any particular type of habitudes, 

 of culture, or acquired skill. Partition due to an island being divided 

 by partial submergence is usually indiscriminate; while migration 

 often produces discriminate partition, as when it brings to a distant 

 island men who are skilled in canoe building and sailing. 



3. Contrasts in Discriminate and Indiscriminate Forms of Action. 



These considerations bring to light the following facts : 

 ( I ) In the survival of innate characters and the success of acquired 

 characters the discriminate forms (i. e., selection and election) are 

 of prime importance ; for in one way or another they are continually 

 acting on nearly every generation of nearly every species. The cases 

 must be rare in which equal success and survival are attained by 

 all the variations; for if variations in other respects have no effect, 

 its variations in vigor will have relation to the degree of survival. 

 In some rare cases there will occur the indiscriminate elimination of 

 all but a very few members of a race or species; and the results 



