between long established invasive species and newly introduced species for evidence of
biotic resistance, yet the invasive fire ants may provide biotic resistance to the spread of
Rasberry crazy ants. Therefore it is important to investigate antagonistic encounters both
between Rasberry crazy ants nests and with fire ant workers.
Because nestmate recognition, territoriality, and activity level are influenced by
diet (Davidson 1997, Howard and Blomquist 2005, Buczkowski and Silverman 2006,
Grover et al. 2007), the diet of an ant can influence aggressive interactions, whether
between species or colonies of a single species. The cuticular hydrocarbons of prey items
can be transferred to ants that come into contact with it, disrupting the ant’s hydrocarbon
profile and affecting nestmate recognition (Buczkowski et al. 2005). Differences in prey
type have been shown to induce aggression between nestmates (Silverman and Liang
2001, Corin et al. 2007, Sorvari et al. 2008) and to affect antagonistic interactions
between nests or colonies of a given species (Liang et al. 2001, Buczkowski and
Silverman 2006, Grover et al. 2007), though the effect of diet on interspecific
antagonistic interactions has not been extensively studied (but see Alloway et al. 1991),
and the effect of diet on competitive interactions between two invasive ant species has
never been studied. Additionally, it has been proposed that invasive ants consume higher
amounts of carbohydrate resources than native ants, which may increase the tempo of
their worker activity, contributing to their high levels of abundance and domination of
resources and territory (Holway et al. 2002). The amount of sugar in a colony’s diet has
been shown to be an important variable in activity level and antagonistic behavior in both
Formica aquilonia and invasive Argentine ants, Linepithema humile (Grover et al. 2007,
Sorvari et al. 2008). Because of the importance of diet in interactions between ants, we
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