Can Cockroach Reproduce Without a Mate?
WouterIn order to reproduce, cockroaches need a mate. Usually, males mate with females, but in some species, males are incompatible with females. In such cases, females produce eggs without a mate. In other species, a female can produce several generations of all-female offspring without a mate.
Female cockroaches can reproduce as early as adulthood. They lay eggs outside of their body in a sac called an ootheca, which contains up to fifty eggs. The ootheca develops inside a bean-shaped sac, which a female cockroach will hold for eighteen days. Eggs are fertilized when the female is pregnant, but a headless cockroach will not hatch her eggs without a mate.
Entomologists from Hokkaido University in Japan studied a colony of 15 unmated females and found that they were able to reproduce without a mate for three years. Parthenogenesis allows cockroaches to form substantial colonies, and allows them to spread to new areas. Scientists say that parthenogenesis is a result of millions of years of evolution. Prior to this discovery, limited genetic diversity was considered a limiting factor in cockroaches.
Cockroaches have evolved to live in a symbiotic relationship with other organisms. They are able to reproduce without a mate when they find a suitable environment. Besides eating food, they will also feed on dead mice, fallen cheese, house plants, and other items.
