The Link Between Cockroaches & Termites

Scientists who study insects suspect that there may be an ancient link between cockroaches and termites. They have found some physical similarities between the two groups of insects. They have also found similarities in biology and behavior. The scientists suspect that the cockroaches might have been the ancestors of the termites.

The Brown-hooded cockroach, Cryptocercus punctulatus is found in the United States. This cockroach eats decaying wood. It is able to digest the wood because it has tiny one-celled animals in its digestive system.

The one-celled animals, called protozoans, actually digest the cellulose in the wood. They protozoans convert the cellulose into sugar so the cockroach can use it. Protozoans perform the same function in the digestive system of many types of termites.

The Giant Northern Termite of Australia, Mastotermes darwiniensis, is a primitive species of termite. This is the only living member of this termite group although scientists have found fossils of these termites. This termite seems to have the abdomen of a cockroach attached to the head and mid-section of a termite.

Mastotermes darwiniensis produces its eggs in masses, or bunches. This is more like a cockroach than a modern termite. Cockroaches produce groups of eggs in small cases, called oothecae. However, modern termites produce eggs one-at-a-time.

The Australian wood cockroach, Panesthia australis, feeds on decaying logs and stumps. The cockroaches make galleries or tunnels in the wood as they eat it. When the cockroaches become adults, they bite off their wings. This enables them to burrow through the wood more easily.

These wood cockroaches live in burrows in the soil in small family groups. Scientists suspect that this might be the way termites began shedding their wings and forming underground colonies.

Scientists who study these insects suspect that the termite, Mastotermes darwiniensis, and the cockroach,
Cryptocercus punctulatus, are evidence of the link between cockroaches and termites.