Research Article

Evidence of Competition Between Two Canopy Ant Species: Is Aggressive Behavior Innate or Shaped by a Competitive Environment?

Table 3

Description of behavioral acts displayed by the ants on Itacolomi State Park (Itacolomi) and the Campus of Federal University of Juiz de Fora (UFJF) during field experiments (**) and laboratory experiments (dyadic encounters) occurring at the lab of the Federal University of Juiz de Fora (*).

ActionReactionNonaggressive

Charge—an ant approaches the other with its mandible open(**) Remain on the bait—after any types of the listed actions, the ant remains in the area, eating the bait(**) Quietly eating—when an ant is standing still, only eating the bait
Bite—grips part of the body of another individual with its mandibles(**) Flee—after any types of these actions it flees not only from the area, but also from the bait(**) Food transport—the individual carries part of the bait to the colony
Espontaneous gaster torsion—the ant curls its abdomen to emits formic acid(**) Retreat—after the mentioned actions, it retreats from the other individual, but does not leave the bait and eats itAutogrooming—cleaning itself
Avoid—when perceiving the proximity of another individual, the first moves away, avoiding the encounterDefensive gaster torsion—after these actions, it exhibits aggressive behaviour by curling its abdomen to emit formic acidTrophallaxis—exchange of regurgitated liquid from one individual directly into the crop of the other
(*) Antennal touching—an ant exchanges antennal touches with the other for identificationFight—after mentioned actions, it grabs the other individual with its jaws and emits formic acidExploring the surroundings—walking around, touching its antennae on the whole extension of the paper where the bait was placed
(*) On alert—an ant stands still with its head and antenna raised, and with its gaster torsed in the posterior-anterior position ready to emit formic acid, if necessary(*) Bite—grips part of the body of another individual with its mandibles in response to any action act(*) Trying to escape—the ant stays on the border of the arena, trying to climb its wall
(*) Charge—the ant advances in the direction of the other with its mandible open ready to bite back

(*) Only in lab experiments; (**) Only in field experiments.