Figure 1 24. 
Weight and age differentials between pairs of females engaged in conflict situations. See figure 123 for additional 
explanation. The large squares represent the means of all losers and all winners. 
Arbitrary age class intervals for losers: 
1. Loser is younger and under 150 days of age. 
2. Sibs of all ages. 
3. Loser is older and over 300 days of age. 
4. Loser is younger but over 1 50 days of age. 
the rats were forced to eat bark of black locust 
trees. A number of these trees from 8 to 13 feet 
high even had their uppermost branches stripped. 
An abundance of food pellets and sections of 
oranges were provided on the evening of July 12. 
There immediately began intense activity relating 
to the acquisition of food. This included both con- 
sumption and transportation. Very few fights 
were observed anywhere in the pen. A nearly 
identical set of observations were made on June 1, 
1948. There had been practically no food avail- 
able to the rats during the previous 3 nights. 
During this evening there was a period of intense 
transportation of food throughout the 4 hours of 
observation. The only observed antagonisms per- 
tained to lactating females chasing the three 
socially low-ranking female sibs 17, 20, and 25 at 
other places than in the Food Pen. On the 
following evening transportation of food was 
greatly reduced, several rats would feed together 
amicably, sexual activity was increased, and there 
was an increase in fighting outside the Food Pen, 
associated with territorial defense and sexual 
activity. 
193 
