THE ALTERATION OF AN AVOIDANCE BEHAVIOR THROUGH 
TIME THROUGH A POPULATION 
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CL 
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cn 
Figure 79. — The alteration of an avoidance behavior through time. This figure was based upon three sets of data. The 
circles represent the lack of reentering traps within the consecutive days of setting traps within a trapping period. The 
squares represent the number of rats still avoiding traps in relation to the length of time between setting traps during con- 
secutive periods of trapping. The triangles are based on those rats for whom one or more trapping periods intervene between 
two consecutive captures. 
ratio of rats exposed to being trapped. This gave 
a nearly 1 to 1 sex ratio. Yet males entered traps 
much more frequently than did females (table 12). 
Table 11. — Frequency of repeating among rats in 
Baltimore residential blocks 
Number 
Number 
marked 
of repeats 
Males 
219 
75 
Females 
193 
75 
Chi Square = 0.321 ; p between 0.5 and 0.7. 
Males in the pen also repeated more frequently 
than did females. However, for those rats which 
were prone to repeat more than once (2d, 3d, etc., 
repeats following an initial capture) females were 
just as prone to enter traps as were males (C with 
D comparison in table 12). This provides the 
clue as to the sexual difference in the response. It 
suggests that there is no inherent attribute of fe- 
males, which prevents them from reacting the same 
as males with reference to an anxiety producing 
experience such as being trapped. One may infer 
that those conditions which bias rats’ behavior to- 
ward a reduction of the avoidance behavior toward 
traps, occur with greater frequency or intensity 
with reference to males; but that once some thresh- 
93 
