Observing different mating tactics in the Japanese scorpionfly

Jun 28, 2022 | News On Japan

Jun 28, 2022 (phys.org) - Owing to the high competition and the prevalence of natural selection, many male insects must develop alternative tactics to mate with a female.

Weaker males who lose in a competition (or loser males) may resort to hovering or sneaking around in order to find a mate. Recent studies have also shown that alternative mating behavior is influenced by environmental factors such as food availability, predation, and population density. For example, scorpionflies—which are often used to study the mating behavior of insects—use three alternative mating tactics—gifting nutritious saliva, gifting food, and forced mating—to obtain a mate. Male Japanese scorpionflies also employ feeding mating (i.e., mating while females feed without gifting them anything or releasing pheromones).

Previous studies looking at alternative mating tactics in scorpionflies have shown that the weaker males of closely-related species employ varying methods to procreate, however no research has been done to find the alternative mating tactics of males within the same species from different geographical locations. To this end, Dr. Ryo Ishihara (who is affiliated to the School of Agriculture and a recipient of the Special Educational and Research Fellowship) and Professor Takahisa Miyatake (from the Faculty of Environmental and Life Science) of Okayama University, Japan, published a study in the Journal of Ethology on 15 June 2022. This study details the differences in alternative mating tactics of Japanese scorpionflies hailing from two different places—the Aichi and Okayama prefectures in Japan. ...continue reading

Typhoons No. 28 and 29 Bring High Waves to Japan's Pacific Coast

Two typhoons moving across the Pacific southeast of Japan are expected to remain well away from the Japanese mainland, but powerful swells could bring rough seas to a wide stretch of the country's Pacific coastline throughout the three-day holiday weekend, according to forecasts updated at 3 a.m. on October 10.

Cyberattacks Spread Across Japan

A series of cyberattacks has disrupted business operations and exposed millions of customer records across Japan, with a ransomware attack on a cloud service provider affecting 495 companies and local governments nationwide, while convenience store operator Lawson has disclosed a separate breach involving more than 2.15 million personal information records.

Japan's First 360-Degree Projection Mapping Opens in Osaka

Japan's first 360-degree projection mapping show will open at the Osaka City Museum of Fine Arts on October 10, transforming the historic building into an immersive world of light, music, and seasonal imagery, with organizers hoping the attraction will also help stimulate the city's nighttime economy.

Tokyo University Professor Wins Nobel Prize in Chemistry

Tokyo University of Science professor emeritus Kenzo Soai has been awarded this year's Nobel Prize in Chemistry together with French chemist Henri B. Kagan for discoveries that transformed scientists' understanding of how chemical reactions can favor one of two mirror-image forms of a molecule.

US Military Halts All Okinawa Operations for 48 Hours

The US military suspended activities by all forces stationed in Okinawa for 48 hours from noon on October 7, an unusual measure following the arrest of a US Marine in connection with a robbery and murder case that has renewed scrutiny of crimes involving American service members.

MEDIA CHANNELS

MORE Sci-Tech NEWS

Humanoid Robots Set to Enter Japanese Convenience Stores

Humanoid robots capable of stocking shelves, managing inventory, packaging products, and serving customers in more than 20 languages were showcased at an international retail industry event in Tokyo on October 8, highlighting the growing potential of artificial intelligence to transform store operations as Japan struggles with chronic labor shortages.

Tokyo University Professor Wins Nobel Prize in Chemistry

Qilin Hacker Detained in Japan

A core member of the international ransomware group Qilin was detained in Japan and handed over to German authorities, according to people familiar with the case, as Japanese companies and institutions face a growing wave of cyberattacks that has exposed nearly 15 million pieces of personal information this month alone.

Japan Startup Begins Building Rare Earth Production Facility

Miresso, a Japanese startup backed by trading house Mitsui & Co., has announced the start of construction of a facility to produce beryllium, a rare metal essential for nuclear fusion power generation, with plans to manufacture 100 tons annually, equivalent to about one-third of current global production.

World’s First iPS Cell Heart Surgery Performed in Osaka

A woman in her 50s with severe heart failure underwent what was described as the world's first surgery using commercially available iPS cell-derived heart muscle sheets at an Osaka hospital on September 29, marking the first practical use of the regenerative treatment.