Vibrations: their signal function for a spider kleptoparasite.

The stealing behavior of Argyrodes elevatus suggests that this kleptoparasitic spider monitors the movements and the hunting success of its web-building host. Wrapping of prey by the host regularly elicits raids from the kleptoparasite. The prey-catching activities of the host generate vibrations that were recorded with a position-sensing photodiode. The recordings indicated that wrapping movements produce a characteristic pattern of vibrations.