Immature bugs forming a protective cluster on a leaf. Note how each individual is oriented away from the group's center and in a slightly different direction around the perimeter. This ensures that there are at least "one pair of eyes" and antennae facing all directions to sense danger (eg spiders or other predators). When danger is detected by one, the others are immediately notified and will scurry away, often to the underside of the leaf. In insects, alarms may be relayed by chemicals, physical movement, vision, contact with each other. In addition, a tight-knit group appears to a predator to be more dangerous (eg larger) prey than a single individual. Thus, group behavior for this species provides more fitness than an isolated insect.
