Meeting Abstract
Ants live in a sensory world dominated by smell, which they experience via their antennae. Damage to the antennae would be expected to diminish a worker’s ability to perform behaviors regulated via olfactory cues – including brood care, detecting pheromone trails, or nestmate recognition. However, Pheidole dentata workers appear largely resilient to unilateral antennal ablation, both behaviorally and neuroanatomically. Workers injured early in adult life have few deficits beyond a reduced ability to follow pheromone trails. This behavioral resilience is correlated with an increase in expression of the synaptic protein synapsin in the higher-order olfactory brain regions ipsilateral to ablation, which suggests there may be anatomical compensation within the brain olfactory pathways in the days following early-life injury that could underlie the behavioral resilience of injured workers. If this hypothesis is true, worker performance would be expected to improve over time after injury as compensatory physiological changes accrue. Using assays to quantify the pheromone trail-following ability of age-matched, 15-day-old ants, we assessed the behavioral consequences of unilateral antennal ablations that occurred either early (immediately after eclosion) or later in adult life (14 days after eclosion). Each individual’s speed and accuracy during trail following was measured and compared to intact individuals of the same age. Injured workers remain capable of following pheromone trails, and our results suggest that workers injured early in adult life may do so with more accuracy than workers injured later in life. These results demonstrate that P. dentata workers are highly resilient to injuries that reduce sensory ability.
