THE ORGANIZATION OF A NUPTIAL FLIGHT OF 
THE ANT PHEIDOLE SIT ARCHES WHEELER 
By E. 0. Wilson 
Biological Laboratories, Harvard University 
Introduction. Most published information on the sexual 
behavior of ants relates solely to the inception of the 
nuptial flights, with very little being recorded of the be- 
havior of the individual reproductive forms during the 
main part of the flights. The reason for this important 
gap in our knowledge is plain — in the great majority of 
ant species the reproductives scatter widely after leaving 
the nest, fly moderate to long distances, and finally mate 
in nuptial swarms far above the head of the human 
observer. 
The nuptial flight is of more than ordinary interest to 
the student of social insects. It is here that the male ants 
exhibit, both in the formation and maintenance of the 
swarms and in subsequent copulatory movements, the 
greater part of their lifetime social behavior. Both sexes 
display fixed-action patterns, conceivably complex in nature, 
that appear only at this time and are apt to be among 
the most stereotyped and species-specific of the entire 
species’ repertory. Judging from other animal groups in 
which the reproductive behavior is better known, the 
nuptial flight patterns of ants can be expected to have at 
least four essential adaptive features, which can be sum- 
marized as follows: synchronization and coordination of 
flight movements within the species, intraspecific sexual 
stimulation to copulatory levels, exclusion of other species 
from the final swarming and copulatory activity, and 
regulation of the species dispersal rate. Descriptions of 
nuptial flight behavior should include, among other things, 
information bearing on these topics. 
Observations. During field work in New Mexico in the 
summer of 1952, the author had an unusual opportunity 
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