You can read Yoshihiro’s recent research article about the influence of photoperiods on caste fate of paper wasps here.

IS: Who are you, and what do you do?

My name is Yoshihiro Y Yamada. I am a professor emeritus at Mie University, Japan: I retired at the end of March 2020. I have been studying the behavioral ecology of parasitoids and host-parasitoid population dynamics over 40 years, and I started to study the social biology of paper wasps around 2005. I will continue to study the social biology of paper wasps as long as I am healthy.

IS: How did you develop an interest in your research?

The late Dr. Matsuura, former professor of Insect Ecology Lab at Mie University, was an expert in the biology of Polistinae (paper wasps) and Vespinae (hornets). I had often talked with him and his students, and I became interested in paper wasps and had several questions about the biology of paper wasps. I am now exploring answers to these questions with my coworker Dr. Yoshimura.

IS: What is your favorite social insect, and why?

Paper wasps. I have observed them for so many years that I feel as if I could understand how they feel, what they want, and what they are thinking about.

IS: What is the best moment/discovery in your research so far? What made it so memorable?

Regarding the field of the social biology of paper wasps, our best discovery is that photoperiod is an important factor for determination of caste fate in the paper wasp Polistes jokahamae (Yoshimura and Yamada 2018, 2021). Bohm (1972) suggested that that photoperiod could influence determination of caste fate in P. metricus, but no researchers have studied the effects of photoperiod in paper wasps since Bohm. Many researchers appear to disagree with the importance of photoperiod. Our preliminary experiments suggest that photoperiod influences determination of caste fate in several other temperate paper wasps. We are sure that most temperate paper wasps use photoperiod as a cue for determination of caste fate.

IS: Do you teach or do outreach/science communication? How do you incorporate your research into these areas?

I sometime teach the biology of bees and wasps, including current hot topics and our recent works to high school students and adults interested in the development of science.

IS: What do you think are some of the important current questions in social insect research, and what’s essential for future research?

Regarding social wasps, mechanisms for caste-fate determination and for establishment and maintenance of queen royalty are important themes for current studies. Comparative studies of several species are essential for future research.  In addition, it is important to keep in mind that several factors are involved in the mechanisms.

IS: What research questions generate the biggest debate in social insect research at the moment?

Regarding social wasps, do adults emerge with a caste-related bias? In other words, to what degree does preimaginal caste determination occur? Answering this question is critical for understanding the origin of eusociality and transition from primitive to advanced eusociality.

IS: What is the last book you read? Would you recommend it? Why or why not?

Pheromones and Animal Behavior: Chemical Signals and Signatures, by Tristram D. Wyatt (2014). I strongly recommend students interested in pheromone communication in animals including insects and vertebrates. The book is quite readable, particularly for people without special knowledge of chemistry. Researchers also might get some hints from the book.

IS: Outside of science, what are your favorite activities, hobbies, or sports?

Gardening. I am trying to make a garden attractive to animals. When my wife and I have breakfast or tea while watching insects, birds and cats visiting our garden, we have a peaceful and wonderful time.

IS: How do you keep going when things get tough?

I go to an onsen (hot spring) area for relaxation. In addition, I practice Zen meditation.

IS: If you were to go live on an uninhabited island and could only bring three things, what would you bring? Why?

My wife Tomoko, survival kit including fishing equipment, and sake. I cannot imagine the world without them.

IS: Who do you think has had the most considerable influence on your science career?

Dr. Tomo Royama and his book, Analytical Population Dynamics: I managed to understand the essence of population dynamics through him and the book.  I hear that his new book will be published soon.  I am looking forward to reading it.

IS: What advice would you give to someone hoping to be a social insect researcher in the future?

I hope that young researchers will have their own questions and explore them, not just follow current hot topics.

IS: What is your favorite place science has taken you?

Campus and experimental farm and forest of Mie University and mountain and hill areas in Mie prefecture: many insects, including wasps and bees, are found in the areas.

IS: If you had unlimited funds to conduct whatever research you wanted, where would you go and what would you investigate?

I would like to go to subtropical and tropical areas and explore the biology of paper wasps.