In animals, reproductive activity and its evolution have attracted attention in studies of evolutionary ecology. Thus, many researchers have constructed theory on reproductive strategy and empirical studies have demonstrated it using multiple technique. I also conduct an evolutionary ecological approach for understanding reproductive dynamics and systems in animals. I use several insects as research materials and mainly focus on their reproductive behaviors as follows: courtship, dispersal, ejaculation, fighting, relocating. Additionally, male morphological characters are in my research area. Typical example of such characters is beetle’s horns and mandibles, and the chracters are exaggerated and are strongly associated with male reproduction.

I am also studying learning behaviors related to the reproductive behaviors. Especially, I’ m interested in learning and fighting. Fighting behavior is often modified by based on prior experience. Generally, prior winning experiences increase (winner effect), and prior losing experiences decrease the probability of winning later contests (loser effect). This phenomenon is explained by what an individual can alter fighting behavior based on the contestant’s or own experience. Winner and loser effect have detected in a wide range of tax and is so common phenomenon. I investigate the learning by prior fighting experience using a horned beetle. Males of the beetle can switch mating behaviors based on their losing experience.

Flour beetles and anobiid beetles are known as major pests of dried foods and drugs, and their distribution areas are tropical to temperate. They invade factory facilities and storage warehouses and then causes great damage to a wide range of agricultural products such as wheat, forage crops, and spices. Because the damage is sometimes enormous, various pest controls has been conducted but there is still room for improvement. In order to improve a control for stored grain pests, I am conducting research on the reproduction and life history of these pests.