1988] 
Binder— Aggression in Heterotermes 
135 
of H. aureus could also have an important influence on the intra- 
and interspecific associations of various termite populations in the 
Southwest. 
Summary 
Aggressive behavior of individuals and groups of Heterotermes 
aureus was studied in the laboratory. Intracolony pairing of soldiers 
resulted in no aggression. Intercolony pairing of soldiers always 
resulted in aggression and the mortality of one soldier. Similarly, 
intercolony pairing of a soldier and a worker resulted in aggression 
and a high rate of worker mortality, while intracolony pairing of a 
soldier and a worker resulted in no aggression. 
The number of encounters between paired soldiers and workers 
decreased with increase in arena size. Soldiers had fewer opportuni- 
ties for aggression, required more time to inflict a fatal snap of the 
mandibles, and more snaps to kill a worker with increase in arena 
size. Consequently, fewer workers had fatal encounters at the largest 
arena size. Workers also had a greater chance for survival by behav- 
ing aggressively or running away and were more likely to attack 
soldiers after multiple encounters. 
Foraging of large groups of termites was simulated in the labora- 
tory to study intra- and intercolony dynamics. Intercolonial groups, 
each with the same number of soldiers, maintained continuous ago- 
nistic engagements, established no common boundaries, and the 
death of all termites resulted. A foraging group with more soldiers, 
however, was able to invade another group’s territory. Workers 
were first to recognize foreign colony members and recruit more 
termites, while soldiers crowded into the orifice to protect existing 
territory. The impact of conspecific, intercolony aggression in natu- 
ral termite communities is discussed. 
Acknowledgments 
The author would like to thank Dr. Susan Jones for supplying 
many undyed termites and the dyed termites used in this study. Drs. 
William L. Nutting, Floyd G. Werner, David N. Byrne and Timothy 
G. Myles made critical comments during the preparation of this 
manuscript. 
