Roaches exist because they are hardy scavengers that fill a role as decomposers in ecosystems.
Role
Cockroaches are scavengers and decomposers. They recycle dead plants and animals.
History
They date back about 320 million years, before dinosaurs.
Species
There are about 4,500 species. Only about 30 live near people, and only about 4 are pests.
Hardy
They can survive weeks without food and can hold their breath for 40 minutes.
Health
They can trigger asthma and allergies.
Control
Seal cracks and remove food.
History and numbers
Cockroaches have existed for more than 300 million years, appearing in the Carboniferous period, long before dinosaurs. There are about 4,600 described species, and only about 30 are pests living near humans. The most common household pests are the German, American and Oriental cockroaches.
- In nature, cockroaches break down dead plants and animals and recycle nutrients. They are also prey for birds, lizards and mammals.
- German cockroaches can produce 30 to 40 eggs per egg case, and a female can create several cases in her life.
- They can survive a month without food and about a week without water, and can hold breath for up to 40 minutes.
Health and control
Cockroaches carry bacteria and allergens, and are linked to asthma in children in urban homes, according to NIH-funded studies. Control uses sanitation, sealing cracks, fixing leaks, gel baits and boric acid, and professional integrated pest management. Store food in sealed containers and remove garbage regularly.
History and numbers
Cockroaches have existed for more than 300 million years, predating dinosaurs. Around 4,500 species are known, but only about 30 are pests. They survive because of flat bodies, rapid breeding and an ability to eat a wide range of foods. In ecosystems they recycle organic matter.
Health and control
Cockroach allergens can trigger asthma. Prevent infestations with sealed food, fixed leaks and clean surfaces. Baits and professional pest control are effective.
Evolution and species
Cockroaches (order Blattodea) evolved from ancestors in the Carboniferous period about 320 million years ago. Fossil roaches look similar to modern ones. They can survive weeks without food and hold breath for 40 minutes. Heads can live hours after decapitation, though they cannot survive long.
Pest species and health
Only the American, German, Oriental and brown banded cockroach are common indoor pests. Roach allergens are associated with asthma in 63 percent of urban children in a study of inner cities. Control with gel baits, boric acid, sealing, sanitation and professionals. Natural roles include decomposition of leaf litter and serving as food for birds and reptiles.
Based on data from the Smithsonian Institution and the National Pest Management Association
