According to the University of Arizona, isopods are omnivorous scavengers that eat dead or decaying plant and animal matter. Some also eat live plants. Isopods are crustaceans featuring a rigid, jointed exoskeleton, prominent antennae and seven pairs of legs.
Isopods breathe through gills and must live in an environment that contains a significant amount of moisture, such as under logs, potted plants and moist leaves. They are minimally beneficial to soil but can be a pest to plants in large numbers. Immature isopods closely resemble adults and undergo four or five molting stages before maturation. Some species of isopod roll into a ball when threatened.