148 John B. Calhoun 



N.1 and A^j in the sense of type one and type two individuals discussed 

 in relation to Eqs. (94) and (95) and (107) are given in Table XIV. When 

 A^j = 2 it means that the second ranked, R = 2, individual is a member of 

 a subgroup of two individuals which share the dominant d-gene B. Like- 

 wise when N j = 2 it means that the third ranked, R = 3, individual be- 

 longs to a subgroup of two individuals each of whom possesses recessive 

 d-gene b. Every individual belongs to a unique A^j and N,. Given these 

 uniquenesses of A^'j and A^j as shown in Table XIV, the respective S^^\ 

 Sl"^ and Vi were calculated respectively by Eqs. (109), (107), and (108) 

 and presented in Table XIV. 



Up to the present I have intentionally maintained the discussion of 

 response-evoking capacity, S, on a nearly strictly theoretical plane for 

 the purpose of clarifying concepts. Even though such theoretical formula- 

 tions may be justified in their own right, regardless of how well they ap- 

 proximate reality, still it is desirable to ascertain whether they are in 

 harmony with observed data. To this end I selected two sets of empirically 

 obtained data. One involves measurements for mice from which velocity, 

 V, may be derived. The second involves the choosing of table partners 

 among groups of delinquent girls. These latter data permit determination 

 of how well the observed choosing can be predicted by Eq. (105). 



XIV. Consequences and Examples of Social Interaction Systems 



A, Velocity Reduction in a Hierarchy of Mice 



I have previously described (Calhoun, 1956) the patterns of social rela- 

 tionships which develop among members of small groups of inbred domes- 

 ticated mice. Whenever two mice passed within a few inches of each other 

 they were recorded as having a contact, regardless of whether or not a 

 detectable social interaction could be detected. During a "contact" two 

 mice merely came within that range of each other for which contentions 

 for status did at times develop. We shall consider the example provided 

 by a group of eleven C57 black, inbred male mice which had developed a 

 stable hierarchy prior to recording the frequency and kind of associations 

 of each individual with his associates. Some pairs of mice contacted each 

 other much more frequently than anticipated on a chance basis, while 

 members of other pairs very infrequently met. These mice are rank ordered 

 in Table XV according to the number of contacts each had with associates. 

 For all practical purposes this order also represents the observed ability 

 to dominate an encounter which precipitated in a fight or flight. That is. 



