7. Tlw Social Use of Space 127 



target diameter, d = 1.0. With reference to Eq. (:i5), a unity value for 

 target diameter merely means that there has been genetic or cultural 

 adaptation to the actual magnitude of d, such that ju = dv/A = 1.0. How- 

 ever, if an individual expresses a value shared by only a few of his associ- 

 ates, he will by this fact be much more likely to be perceived by his as- 

 sociates, and thus more likely to be reacted to by them. His target diam- 

 eter will be increased. Furthermore, it is logical to assume that the larger 

 an individual's target diameter, the greater will be the response evoked 

 from associates. In so long as all other d xqXwq characteristics remain 

 identical among the members of the group, the one which does vary among 

 members will assume the sole role of influencing target diameter. As a 

 first approximation this response-evoking capacity, which I will call S, 

 of a particular d value can be taken as being inversely proportional to the 

 probability j) of its being encountered among the members of the group of 

 N individuals. 

 Therefore : 



S = l/v (87) 



Where only one component of d varies, and since those shared compo- 

 nents of d may be ignored, d ^ S. For the special case where all members 

 have the same d: 



M = {dv)/A = {Sv)/A = 1.0 (88) 



Furthermore, where area. A, remains unchanged at the value appropri- 

 ate to Nb it has the relative value of 1.0. Therefore: 



Sv = 1.0 



S = l/v (89) 



And considering Eqs. (87) and (89) 



V ^ p (90) 



Lastly: 



V = l/S (91) 



A'ariability of the target diameter d among individuals means that d 

 comprises an assembly of traits, physical size, color, vocalizations, behavior, 

 and attitudes or values, d is the total complex. Components shared by all 

 members will be referred to as {d) . Those remaining traits, through which 

 an individual differs from its associates, represent a genetically and cul- 

 turally determined phenotype to which the response evoked from associ- 

 ates is a function. By response I here refer solely to actions reflecting the 

 choosing or rejecting of an associate. Such a response may be a function 



