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REV. J. T. GULICK ON DIVERGENT EVOLUTION 
the weak is not a form of Segregation, bat rather a cause that 
prepares the way for Segregation, by forcing portions of the 
community out of their inherited relations to the environment. 
CHAPTER III. 
Description and Classieication of the Causes of 
Cumulative Segregation.* 
A. Enyironal Segregation. 
Environal Segregation is Segregation arising from the relations 
in which the organism stands to the environment. 
It includes four classes, which I call Industrial, Chronal, 
Spatial, and Artificial Segregation.! 
( a ) Industrial Segregation 
is Segregation arising from the activities by which the organism 
protects itself against adverse influences in the environment, or 
by which it finds and appropriates special resources in the 
environment. 
The different forms of Industrial Segregation are Sustentational, 
Protectional, and Niditicational Segregation. 
Eor the production of Industrial Segregation it is necessary 
that there should be, in the same environment, a diversity of 
fully and of approximately available resources more or less 
separated from each other, and in the organism some diversity 
of adaptation to these resources, accompanied by powers of 
search and of discrimination, by which it is able to find the 
resources for which it is best fitted and to adhere to the same 
when found. 
The relation in which these causes stand to each other and 
through which they produce segregation may be described as 
separation according to endowment produced by endeavour 
according to endowment. 
It is evident that if initial variation presents in any case a 
diversity of adaptations to surrounding resources that cannot be 
* In the following chapters numerals are attached to what I consider sepa- 
rate causes of segregation independent of human purpose. 
t Francis Galton has suggested another class, which might appropriately be 
called Fertilizational Segregation. 
