MIZUNO, Riou

Research Area:　Environmental Science　
Research Specialization:　Insect Ecology　
Name:　MIZUNO, Riou

Key words; Ant, natural history, behavior, biodiversity, evolution

Recent Research

1．Evolution of army ants; a comparative study of Non-army doryline ants

Army ants are predators in tropical terrestrial  ecosystems. They have huge colony sizes and unique life history traits, such as nomadism, mass raid, and specialized predation on other ant species. The evolutionary history of the army ants is still mysterious. The biology of phylogenetically related “non-army ant dorylines”, the key to accessing this mystery, is also not well studied due to their rarity. We are conducting a field natural history study on these non-army ants to fill this knowledge gap and consider the evolution of the army ants.

2．Diversity of life history traits of Strumigenys ants.

Strumigenys is a highly diverse ant genus that contains nearly 900 species, distributed across biogeographic regions. Some of them have spring-loaded, ultra-fast closing mandibles, which are called “trap-jaw”, and prey on small soil arthropods by using these jaws. We are trying to understand the background of their extreme diversification and ecological success through comparative studies on their biology across different biogeographic regions.

3．Evolution of sophisticated collective behavior in insects

Social insects perform various sophisticated and complex collective behaviors. But it is difficult to intuitively understand what evolutionary processes gave rise to such behavior. We are trying to understand it from comparative behavioral studies by using two material species: 1) non-army ant doryline species performs army ant-like raid behavior; 2) Leptogenys cyanicatena,known for “self-assembling chain” behavior for transporting huge prey millipedes.

Selected publications