The Role of Associative Learning in the Feeding Behavior, Development, and Fitness of Antlions
Previous studies have established the importance of associative learning in actively foraging insects, including bees, wasps, flies, grasshoppers, cockroaches, and locusts. This observation of learning in such a wide range of species has revealed the significance of associative learning for increasing an individual s fitness, that is, the individual s ability to survive and successfully reproduce. To date, no published study has investigated the role of associative learning in sessile predators, like antlions (Neuroptera: Myrmeleontidae). Thus, the purpose of the current study was to determine the role of associative learning in antlion feeding behavior, development, and fitness. In the current study 56 antlions were assigned to either a learning (LRN) (n = 28) or a control (CON) (n = 27) condition. One prey item was delivered to each subject once per 24-hour training day until the subject molted or pupated, which concluded the experiment. Data were analyzed through 70 training days. Subjects in the LRN condition received a vibrational cue, namely 4.5 mL of dropping sand, immediately prior to delivery of the mealworm. CON subjects received the same cue at a time independent of the feeding. Feeding behavior (extraction efficiency rate) and pit volume were measured each training day. In addition, sand-throwing behavior was observed. Third instar LRN subjects demonstrated increased sand-throwing behavior in response to the cue. In addition, a survival analysis revealed that antlions in the LRN condition to demonstrated greater fitness as measured by faster development and pupation.