rpenter ants are large and typically black in color. Unlike termites, carpenter ants do not eat wood and rarely cause damage to structures. In California, their nests may occur inside the wooden parts of homes, but in such cases they usually have occupied abandoned drywood termite nests. Carpenter ants eat a variety of things, including other insects.
A common carpenter ant.
Army Ants. The most spectacular and well-known ants are the legionary, or army, ants of the humid tropical forests. These ants do not construct nests, but form temporary clusters called bivouacs in the shelter of fallen trees or in other partially exposed situations. The workers form a solid mass up to a yard wide, which consists of layer after layer of individuals hooked together by their tarsal claws. The queen, larvae, pupae, and eggs are located in the center of this mass.
An army ant, not considered as dangerous to humans as commonly believed.
The night is passed in a tight cluster, but at the first sign of light the cluster dissipates and hoards of workers fan out from the bivouac in all directions. Soon, one or more columns form and begin to search for food. The workers lay down a pheromone trail for others to follow while the soldiers guard the perimeter of the trail. Workers form numerous columns; changing positions behind the advancing hoards of ants—flushing out large numbers of prey (arthropods, small reptiles and rodents). The prey is stung, killed and transported to the rear as food for the larvae. At the end of the day the cluster is reformed. When the food supply is depleted around the area of the bivouac, the colony relocates.
Some colonies of army ants may number as high as one million individuals. Because of the spectacular size of their colonies and ‘raiding’ nature of these insects, they have been used repeatedly by the motion picture industry. Actually army ants pose no threat to humans or other large animals.
The authors recently had the opportunity to observe army ant behavior in Costa Rica. One morning we were walking