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[Vol. 89 
trial pitted termites from different colonies. After the 12 hour 
encounter all dead termites from selected trials were collected and 
examined for injuries under a dissecting microscope. 
RESULTS 
Survival percentages of termites involved in each trial are pre- 
sented in Table II. For conspecific interactions among members of a 
single caste (soldier vs soldier or worker vs worker), it was not 
possible to differentiate colony affiliation so a single survival per- 
centage is indicated. These figures indicate whether or not a fight 
ensued, although it is impossible to determine if one colony suffered 
more or less mortality than the other. 
Variability within and between blocks of Table II is high. Among 
some replicates mortality is low for both groups of interacting ter- 
mites (signified by a at the base of the block). Some encounters 
suggest consistent “victors”, represented by an arrow pointing in the 
direction of that party. Other groups of interactions indicate agonis- 
tic behavior on both sides (‘+’), without clear assignment of a 
“winner” or “loser”. 
All interspecific worker-worker encounters resulted in a fight, often 
with a trend suggesting a “dominant” species but with sufficient 
variation among trials to prevent assigning a “winner”. Such varia- 
tion may result from relative differences in individual colony nutri- 
tion, age, health, and history. For example, an interaction between 
two strong colonies may be quite different from a similar encounter 
between members of a weak and a strong colony. It should be noted 
that soldiers are absent during worker-worker trials, which may 
affect the excitability and response of workers. 
Intraspecific worker-worker engagements demonstrated variable 
aggression within Nasutitermes corniger and N. ephratae, and no 
lethal attacks in any of the Amitermes or Armitermes trials. Fight- 
ing among conspecific Nasutitermes colonies is variable and appar- 
ently influenced by as yet uninvestigated factors. In these experi- 
mental trials, aggressive interactions generally occurred, although in 
all but one 1 V. corniger trial well over half of the workers survived 
the 12 hour meeting. I have previously observed both extremes in 
conspecific Nasutitermes corniger encounters: 100% mortality and 
100% survival, even among colonies from distant locations. Dudley 
& Beaumont (1889a,b) report that mixing two N. corniger colonies 
