1. Pokémon are of immense interest as living beings

 

In June 2025, An Illustrated Guide to Pokémon Ecology – Pokécology was published in Japan by Shogakukan. Currently available only in a Japanese language version, the guide was planned by Yoshinari Yonehara, an expert in animal behavior and ecology who holds a PhD from the University of Tokyo’s Graduate School of Agricultural and Life Sciences. Yonehara, a Pokémon employee, has been a Pokémon fan since childhood, and when the Pokémon Sun and Pokémon Moon video games were launched, Yonehara became strongly attracted to the regional forms of Pokémon – the variants of a Pokémon species found in different habitats.

 

△Exeggutor, the Coconut Pokémon, changes appearance depending on its environment. (from An Illustrated Guide to Pokémon Ecology – Pokécology)

 

What initially piqued his interest, Yonehara says, are the realistic characteristics of each Pokémon. This led to his discovery of Pokédex, the illustrated encyclopedia giving detailed information on every Pokémon. Whenever a Pokémon is captured in a video game, its data has been registered in Pokédex. Data varies slightly according to the series in which the Pokémon appears; for example, in one series information may focus on a Pokémon’s habitat, while in another it may describe its foraging habits.

 

△ A Pokémon’s data can differ depending on the publication in which it appears.

 

Pokédex is filled with large amounts of information on each Pokémon’s habitat. Yonehara believed that if that data were arranged systematically, people would view and understand Pokémon from a completely new perspective. And so a project was set in motion to gather all the information on Pokémon accumulated to date into a single volume. The resulting book would encompass all Pokémon from the original Pokémon Red and Pokémon Green versions through the most recent Pokémon Scarlet and Pokémon Violet.

 

2. A guide collecting and collating a huge amount of data from Pokédex

 

The book Yonehara wanted to create was one in which readers would learn new aspects of Pokémon through the perspective of behavioral ecology. Shunning difficult, specialized terminology, he set to compiling a work in which the reader would come to recognize the specific traits of Pokémon with each turn of the page.

 

To begin, Yonehara systematically compiled the explanations provided in Pokédex. He transferred this information to a spreadsheet and began analyzing the ecological data of each Pokémon.

 

To cite an example, the explanation for the Seed Pokémon Bulbasaur in Pokédex describes photosynthesis as the means by which Bulbasaur acquires its energy. It adds that a “seed” is one of this Pokémon’s organs, and as it evolves, Bulbasaur undergoes a physical transformation in the form of a blooming flower. Yonehara added tags with information like this for each Pokémon, enabling the reader of his spreadsheet to go through a tremendous amount of data compiled for each type of behavior or trait.

 

Completing this phase of his project took Yonehara approximately two years. By the end, he had included some 7,500 items on the spreadsheet. Once this vast amount of information was systematically categorized, Yonehara next rearranged the information from the perspective of behavioral ecology.

 

For example, for Pokémon listed as having a “territory,” Yonehara subdivided this aspect into a number of possibilities: how the Pokémon makes its territory known to others, how it gives warning to potential intruders on its territory, how it physically defends its territory, etc. In this way, Yonehara refined the data on the behaviors and traits of Pokémon based on our understanding of the creatures inhabiting our real world.

 

 

Another feature Yonehara incorporated into the new Illustrated guide is inducing children to think on their own about the ecology of living beings. The work opens with a description of how to study the ecology of Pokémon, while toward the end Yonehara prepared “Wondrous Discovery” sheets on which young readers can write the results of their observations.

 

△Explanation describing what perspective to use when observing Pokémon (from An Illustrated Guide to Pokémon Ecology – Pokécology)

 

3. Two experts combine their knowledge and talent to stress the realism of Pokémon

 

One other person played an instrumental role in getting young readers to understand the ecology of Pokémon: illustrator Chihiro Kinoshita, a graduate of the PhD program of the University of Tokyo’s Department of Agricultural and Environmental Biology.

 

Like Yonehara, Kinoshita too is an expert in behavioral ecology, and he has published a number of books on the behavior and traits of different members of the animal kingdom. Yonehara says that whenever he informed Kinoshita which behavior he wanted him to depict, even using specialized terminology at times, Kinoshita immediately grasped what Yonehara had in mind. In this way, Yonehara always felt completely at ease collaborating with Kinoshita.

 

Kinoshita’s expert knowledge was put to outstanding use on many pages of the new illustrated guide. A typical example is the scene describing how the Woodpecker Pokémon Pikipek, with considerable effort and skill, drills holes in tree trunks in order to safely store its food.

 

△Pikipek shown pressing its tail feathers against a tree (from An Illustrated Guide to Pokémon Ecology – Pokécology)

 

The illustration of Pikipek created by Kinoshita shows it pressing its tail feathers against a tree. This is precisely the behavior exhibited by woodpeckers in the real world. Yonehara says that when he requested Kinoshita to create Pikipek’s illustration, he didn’t specify such a detailed depiction. But, Yonehara says with a smile, Kinoshita came through intuitively, naturally and brilliantly, without the need for excess words between them.

 

Some details that couldn’t be fully included in the explanations given in the guide were in this way provided through Kinoshita’s remarkably life-like illustrations.

 

Another feature of the new guide is that it provides information not only on each Pokémon under discussion, but also on other Pokémon that appear in the background. For example, Tapu Bulu is a Pokémon that declares its territory by sound. The background of its illustration shows other Pokémon that similarly use sound for the same purpose.

 

4. We hope the guide piques children’s interest in creatures of the real world

 

From the moment it went on sale, An Illustrated Guide to Pokémon Ecology – Pokécology drew numerous enthusiastic responses to its observations of Pokémon from a totally new perspective.

 

Many readers commented that, for the first time, they came to understand just how the various Pokémon live. They added that what made them especially happy was the sense they received that Pokémon truly do exist. Others expressed the hope that young readers, when seeing a creature of the natural world on their way to school, in class, or on a TV program, will notice behavior which they first learned about in the guide.

 

In these ways, Pokémon and the creators of An Illustrated Guide to Pokémon Ecology – Pokécology hope this new book on Pokémon will serve as an enjoyable and useful introduction to the world of the creatures living in the real realm all around us.