Female cockroaches living together more likely to see asexual reproduction
Japan Times -- Mar 14
Female cockroaches living in groups with other females are more likely to have their unfertilized eggs hatch, a research team at Hokkaido University has found, providing a possible explanation for the reason the insect has managed to survive for hundreds of millions of years.

When three female American cockroaches - a species widely found throughout the world - were placed together in a study, ootheca, or the egg case of the cockroaches, formed more quickly than when a single female was observed, the team said.

“It explains well the fact that several female cockroaches will be able to maintain a colony in a more stable manner than a single female cockroach,” which can be regarded as a sign of cooperative behavior that is optimized for reproduction seen in other insects like white ants, the research team said in a news release Monday.

A group of more than 15 female cockroaches was able to maintain a colony for more than three years, indicating that ootheca form faster the more cockroaches there are, it said.

“We found that ootheca formation is facilitated when a female cockroach recognizes another female by touching it with their antennae, which are also used for smelling and tasting,” said Ko Kato, a graduate student who took part in the study.

News source: Japan Times
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