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.
STREET FOOD! We're back for more in one of Japan's most traditional cities, Nara.
What was once Japan's capitol is now a place loaded with delicious street food for humans and deer alike. So, what's Nara got to offer? I hope you're hungry! (ONLY in JAPAN )
Japan's Liberal Democratic Party on Friday submitted a record of email exchanges in which Akie Abe, Prime Minister Shinzo Abe's wife, denies her alleged payment of one million yen to an embattled school operator. (Jiji)
Japanese Defense Minister Tomomi Inada ordered the Ground Self-Defense Force on Friday to withdraw its engineering troops taking part in a U.N. peacekeeping mission in South Sudan by the end of May. (Jiji)
New textbooks authorized for use in Japan's senior high schools from April next year contain more descriptions on foreign and defense policies undertaken by Prime Minister Shinzo Abe's government, such as the ability to engage in collective self-defense, according to the results of the education ministry's latest textbook screening disclosed Friday. (Japan Today)