Table 48. — Colony e: Area III burrow ( including boxes 23, 26, and 27) April-May 1949 
Rat J s number 
Place of birth 
Maturity 
index 
May 
weight 
May 
wounds 
Surviving young (21) 
Placental 
scars 
Males: 
703 
SAB 
1.75 
510 
9 
462 * 
Area IV. 
11.17 
490 
0 
786 
N.AB 
1.20 
583 
25 
742 s 
Area IV 
11.25 
470 
0 
Tag lost 
508 
0 
Mean 
1.84 
512 
6. 8 
Females: 
71 
SAB 
1.25 
520 
5 
Yes. 
10 
655 
SAB 
1.40 
428 
6 
Yes 
15 
749 
Area II 
II. 00 
434 
3 
No 
766 s 
Area IV 
11.13 
440 
0 
No 
11+ 
740 s 
Area IV 
1 1 . 00 
414 
7 
Yes 
352 ‘ 
Area IV 
1.20 
484 
4 
No 
915* 
Area IV 
11.25 
332 
5 
do 
797 » 
Area IV 
11.70 
426 
0 
do 
11 + 
37 
SAB 
( s ) 
Mean 
1.87 
435 
3. 8 
12.0 
■These rats were either the young of female 37, or at least were closely associated with her in the same burrow with 
her young of a similar age. 
2 Young of female 75; see colony d. 
3 She is a senescent female too old to breed. 
two colonies. Furthermore, 6 of the 9 invading 
rats forming the Box 25 burrow aggregate in 
February 1949 were still in Area III during March 
to May 1949; but none of the 16 rats forming the 
lower ranking Box 23 burrow aggregate in February 
1949 were here during the following spring. This 
difference has a Chi-Square of 5.579 with a 
probability of less than 0.02. Thus, even during 
the prebreeding season, there was local differentia- 
Table 49. — Growth and later residence of those females 
born in Area III during 1948 and who survived to 
May 1949 
Number 
Maturity 
index 
Member 
of colony 
63 
1.14 
c 
62 
1.81 
f 
658 
1.90 
g 
661 
11.25 
g 
60 
11.56 
h 
58 
11.67 
h 
659 
11.83 
j 
tion into subcolonies of rats inhabiting Area III. 
This differentiation was on the basis of which rats 
were to remain here, and which ones these were 
going to exclude by the beginning of the breeding 
season. 
Colony e demonstrates that a marked homo- 
geneity of origin of members of a colony does not 
not necessarily confer upon them a favored status. 
The majority of the members of this colony came 
from Area IV, which historically was composed of 
socially lower ranking rats than those from Area I 
or the South Alley Burrow. In line with this 
difference in place of birth both of the colony e 
females born at the South Alley Burrow had 
surviving litters, whereas only one of the colony e 
five females born in Area IV did. 
The influence of male 786, as presumably the 
dominant male of colony e, in the formation of 
this colony was discussed on page 202. One 
further comment about him is pertinent. He 
and five other males born at the North Alley 
Burrow during 1948 survived into the 1949 
breeding season. All remained at or frequently 
208 
