CHARACTERISTICS OF LIVING MATTER 9 



4. REGULATION AND ADAPTATION, INTEGRATION 



These characters, while based on irritabihty, have a 

 more distinctively organic or vital quality — are manifes- 

 tations of a higher plane of organization — than the simple 

 property of responsiveness to stimuli. Fundamentally 

 they are related to the characteristic self-conserving 

 property of the organic individual or species; this prop- 

 erty is exhibited by all naturally occurring organisms; 

 i.e., the structure and activity of the latter are of such 

 a kind as to favor a permanent or stable existence in the 

 environment. Under the terms regulation and adapta- 

 tion, we include, in their broadest appHcation, all of 

 those features of adjustment — structural, chemical, and 

 active — which are especially characteristic of living as 

 distinguished from non-living systems. The organism 

 is "fitted" to its environment; the reciprocal relations 

 between the two are so balanced or correlated that the 

 species persists. In other words, the properties or 

 activities which have special "survival value" are those 

 which we designate as adaptive. Adaptations may be 

 (i) of a static or morphological kind — non-temporal in 

 their reference — e.g., when the structure of the organism 

 shows a correspondence with the unchanging features of 

 its environment. Perhaps the most general and wide- 

 spread example of such static adaptation is seen in the 

 general plan of bodily structure common to most free- 

 living animals — bilateral symmetry combined with 

 antero-posterior and dorso-ventral differentiation.^ Or 



^I have discussed more fully the general conditions that render 

 this type of structural plan adaptive in a paper on purposive and adap- 

 tive behavior in the Journal of Philosophy, Psychology and Scientific 

 Methods, XII (1915), 589. 



