Most eusocial wasps are in the insect family Vespidae. In the temperate zone familiar eusocial wasps of this family include paper wasps, yellowjackets, and hornets. Many more species of eusocial wasp occur in the tropics, and in the American tropics nests, like this Polybia nest in the rainforest of Costa Rica, are common.

Polybia and other, similar, tropical wasps found new nests by swarming. Many queens establish the nest and cooperate in rearing workers, which construct the nest and forage for food.

This nest is constructed of chewed plant materials, mixed with wasp saliva. This protective paper casing protects the brood from potential predators, such as birds, and from parasites. Workers are armed with a painful sting, and dozens or hundreds of workers fly from the nest in response to disturbances.

As the colony of wasps grows, the nest is enlarged by adding to the outer covering. Different colored layers of covering material are visible in this picture. Inside the nest, combs, also made of paper, house the developing larvae. The flanges, projecting from the nest surface, may help to camouflage the nest among dead leaves. The dark circle on the lower right corner of the nest is the entrance hole.