166 
Psyche 
[Vol. 90 
At 2:03 p.m. on November 15, 1982 a nest of moiety B' was 
transferred to the arena of moiety B" immediately following the 
B'-B" pair-tests described above (workers of B' and B" which had 
been used in the pair-tests were not returned to their respective 
arenas until after the nest-transfer experiment was complete). 
Again, in the most conspicuous contrast to the experience in B'-B"' 
pair-tests, but in the same pattern as the reaction when the nest of B' 
was introduced to A, immediate mass hostility was exhibited 
between the two fragments. Eight minutes after introduction it had 
become general, with many interlocked pairs. By 6:55 p.m. pairs 
“clinched” and stinging were still present within the introduced B' 
nest, and disturbed young males present in that nest were emerging 
prematurely. This condition persisted until the following day, by 
which time it appeared that occupation of the B' colony by 
members of the B" moiety had been completed, and things settled 
down, leaving many dead workers in the arena. 
It therefore became clear that previous dietary history was not a 
dominant factor in mediating the mass hostility so conspicuous 
between A and B on the one hand and B' and F' on the other. It 
remained to test whether it was in fact the presence of the “foreign” 
nest with its soil that triggered the mass incompatibility or simply 
the introduction of many alien workers at one time near the home 
“site” — a “mass” effect of numbers on the one hand or the possible 
influence of a familiar site for the test, rather than fingerbowls, on 
the other. To check this, at 8:00 a.m. on November 18, 1982 ten 
workers of B' were introduced together into the B" arena, being 
placed close to the entrances of the B'' stack of nests. Reactions were 
completely compatible until 8:25, when two of the introduced 
workers were seen being dragged about. This continued for the next 
five minutes, when one was released, the other being freed by 8:30. 
There was then entire quiet and apparent compatibility until 3:15 
p.m., with no further aggression except that a single worker (living 
and uninjured) was being dragged about the arena at 12:00 noon of 
the following day. The remaining nine were apparently “adopted”. 
Simultaneously with this experiment, the reciprocal transfer was 
carried out. (10 workers of B" introduced into the B' arena, near the 
entrances to the B' nests). The experiment was begun at 8:10 a.m. 
Here also there was complete compatibility, except for two workers 
seen dragged out of a nest entrance at 3:15 p.m., as observations 
