Orientation towards prey in antlions: efficient use of wave propagation in sand.

Substrate-borne vibration for locating mates, predators and prey is widespread in the animal kingdown. Antlion larvae dig funnel-shaped traps to catch ants and they are totally immersed in dry sand. We used a playback setup reproducing an ant walking on sand to clearly demonstrate that antlions use sand-borne vibrations to locate their prey. Half the tested animals moved towards the stimulus source. The shoot angle of sand tossing was very close to the target angle, indicating excellent ability to perceive stimulus direction. We also discuss orientation mechanisms in sand, a medium with highly unusual wave propagation properties.