Sedentary antlion larvae (Neuroptera: Myrmeleontidae) use vibrational cues to modify their foraging strategies

Learning abilities are exhibited by many animals, including insects. However, sedentary species are typically believed to have low capacities and requirements for learning. Despite this view, recent studies show that even such inconspicuous organisms as larval antlions, which employ an ambush predation strategy, are capable of learning, although their learning abilities are rather simple, i.e., limited to the association of vibrational cues with the arrival of prey. This study demonstrates, for the first time, that antlion larvae can use vibrational cues for complex modifications of their foraging strategies. Specifically, antlion larvae rapidly learn to differentiate between the vibrational cues associated with prey of different sizes, and they save resources by ignoring smaller prey in favour of larger, more energetically profitable prey. Moreover, antlion larvae can learn to associate vibrational cues with the loss of their prey, and they respond by burying their victims under the sand more often and more rapidly than do individuals with no opportunities to form such associations. These findings provide not only new insights into the cognitive abilities of animals but also support for the optimal foraging strategy concept, suggesting the importance of maximizing fitness output by balancing the costs and benefits of alternative foraging strategies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10071-016-1000-7) contains supplementary material, which is available to authorized users.