An oily cuticle protects them from dehydration. Life Cycle Courtship patterns vary with species. When the American cockroach is ready to mate, the female produces a chemical odor, or pheromone, that attracts males. Other species have more elaborate patterns, including hissing noises, bobbing and waving of the abdomen, or nibbling. The males of one African species form dominance hierarchies, and the females preferentially mate with the dominant male.
Species also vary with respect to carrying the egg case, or ootheca.
The American cockroach quickly deposits the ootheca, hides it, and leaves it to hatch. German cockroaches keep the ootheca extended from their ovipositor, depositing it only when the eggs are ready to hatch. An ootheca contains from 16 to 32 eggs, depending on the species. Ecology Cockroaches, through their numbers, are an important part of the ecosystem. They can eat a wide range of substances, including other cockroaches, because of the variety of bacteria and protozoans in their gut, and they play an important role in the rapid decomposition of forest litter and animal fecal matter.