What Is the Purpose of Compound Eyes?

purpose-compound-eyes Credit: USGS Bee Inventory and Monitoring Lab/Flickr/CC-BY-2.0

Compound eyes give insects an expanded field of view, according to University of Minnesota (UMN). Compound-eyed insects, such as the dragonfly, can see objects from all angles except for the blind spot their bodies create. Some boast dual-vision systems which allow them to see darkness, light and color. Compound eyes also help insects estimate the distance between their bodies and other objects, states PawNation.

According to PawNation, the compound eyes of a grasshopper have thousands of ommatidia, which are units equipped with lenses. The lenses have a hexagonal outline. All the ommatidia absorb light in small portions from the full image at which an insect is looking. The tiny “shots” captured are transmitted to the brain of the insect where they are processed into one complete picture.

Dual-vision capacity is evident in pollinating insects, such as bees, which can easily pick out a mature flower from one that is maturing or dying, UMN elaborates. Yet, compound eyes are some of the worst-performing in the animal kingdom, where it is necessary to resolve details of an object being observed. For instance, a small section of the human eye resolving at 1 meter can pick out many details of a human hand, while a similar arc of an insect eye, at its best capacity and observing from the same distance, can only identify an outline of the object.