Motion parallax as a source of distance information in locusts and mantids

This review article is devoted to results on distance measurement in locusts (e.g., Wallace, 1959; Collett, 1978; Sobel, 1990) and mantids. Before locusts or mantids jump toward a stationary object, they perform characteristic pendulum movements with the head or body, called peering movements, in the direction of the object. The fact that the animals over- or underestimate the distance to the object when the object is moved with or against the peering movement, and so perform jumps that are too long or short, would seem to indicate that motion parallax is used in this distance measurement. The behavior of the peering parameters with different object distances also indicates that not only retinal image motion but also the animal’s own movement is used in calculating the distance.