Flies have heads that can move with eyes and most have large compound eyes on the left and right sides of their heads, with three small ocelli on top. To control the direction of view, the optical range is analyzed by a set of motion-sensitive neurons. One part of these neurons is thought to be used to estimate the parameters of one's own movement, such as yawing, rolling, and turning. The other neurons are thought to be used to analyze the visual material itself, such as identifying the shape of a figure on the ground using motion parallax. antennae vary in shape, but are often short to reduce the load on the fly.
