J. The Social Use of Space 25 



of the point of capture, and that 0.495 of the females and fawns were ob- 

 served within 100 yards of the point of capture, and utilizing Eq. (27) and 

 the fact that R = r/a, a, in the sense of d, for males is 270 yards and for 

 females and fawns is 137 yards. On this basis the observed cumulative 

 probabilities of observation were converted into sigma units of distance 

 from the point of capture and posted on Fig. 8. 



There is forced conformity with Curve III, Eq. (27), at 0.74(7. However, 

 the further proximity of the observed points, up through l.oa, to Curve 

 III provides credence to the general formulation of Eq. (27). Observa- 

 tions may occur when the animal is on either the outward or return por- 

 tions of a trip or during the wandering at the end of a trip. The more an 

 animal wanders at ends of trips relative to the cumulative travel path, 

 excluding wandering at the end of trips, the farther the observed points 

 may be expected to diverge from Curve III and approach Curves I and II. 

 In fact, were it possible to obtain adequate assessments of home range in 

 terms of observations made of the individual during its travels as well as 

 of data derived from responses such as entering traps, it would be possible 

 to calculate wandering distance at r. 



V. Summary of the Concept of Home Range 



Developing an attachment to a restricted region to which an animal 

 returns after wandering outward from it requires that the individual belong 

 to a species which has evolved the capacity to retain the memory of prior 

 experience. If an animal remains at the site of its birth there is no question 

 that the immediate surroundings of this site will be known better than 

 more distant ones. However, many individuals are forced from the site of 

 their birth. The term "forced" is here used as a postulate derived from the 

 observed avoidance of fields containing strange stimuli. Parsimony de- 

 mands the assumption that an animal will remain at home unless forced 

 away, until it can be shown that an animal will change its home in the 

 absence of any factors which might tend to expel it. 



Even if an animal is expelled from the site of its prior residence and 

 begins to wander at random, it will be chance cover some areas more fre- 

 quently than others. As it thus becomes familiar with a restricted area, 

 it will increase its avoidance of less frequented areas. This process will lead 

 to a repeated frequenting of a particular restricted location which can be 

 defined as "home." Home may acquire other attributes, such as the con- 

 struction of a den, but such additional attributes are not necessary for a 

 site to become a home. 



At irregular, probably random, intervals the individual engages in ex- 



