Cockroaches

Abstract

The order Dictyoptera comprises cockroaches and mantids. A few species have become domestic pests worldwide and, because of their close association with humans, food and infected material, have become incriminated in the mechanical transmission of disease. There are some 4000 species of cockroach distributed throughout most parts of the world, although most are of little or no significance to humans. Many species are diurnal in habit and a large proportion live in tropical rain forests. They are closely related to the mantids (Fig, 13.1) and were, until recently, classified in the order Orthoptera with the grasshoppers and crickets. They are perhaps one of the most successful of all insect groups and have changed little in appearance in 250 million years. Approximately 50 species have acquired the habit of domestication to a greater or lesser extent, and some have followed humans to most parts of the globe, becoming widespread and significant domestic pests.