distribution of fire ant workers, between 21 and 36 fire ant workers from each of 10
colonies were classified as small, medium, or large. These classifications were based on
visual estimates based on the range of worker sizes, rather than specific measurement
ranges. The average percentage and standard deviation of workers in each category was
calculated (Table 2.1).
Overall average aggression score, average number of fire ants fighting, and
average number of crazy ants fighting all were analyzed using a one-way ANOVA to
determine the effect of fire ant size on the response variables. Average mortality after 10
minutes was minimal and often zero, thus it was not analyzed. Mortality for both crazy
ants and fire ants after 1 hour was non-normal and could not be transformed to achieve
normality and therefore was analyzed for an effect of fire ant size using a Wilcoxon
signed rank test. To determine if the average number of ants fighting differed by species,
the difference between species in number of ants fighting was taken for each aggression
assay and the resulting values were tested for significant deviation from zero using a
Wilcoxon signed rank test. To test for a species difference in mortality after 1 hour, the
differences were tested for deviation from zero using a 1-group, 2-tailed t-test. The
differences for both response variables were also tested for a fire ant size effect using
Wilcoxon signed rank tests. Additionally, average crazy ant and fire ant mortality after 1
hour was compared to survival of control Petri dishes containing either 5 crazy ants or 5
fire ants using Wilcoxon signed rank tests on the fire ant mortality and the square root of
crazy ant mortality after 1 hour.
Crazy ants receiving different diets
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