TOKYO WEEKENDER



 

The renowned chimpanzee was famous for her cognitive abilities
The Kyoto University’s Center for the Evolutionary Origins of Human Behavior announced this week that Ai, a genius chimpanzee known for her cognitive abilities, has died at the age of 49.

According to the center, she died on January 9, 2026, of old age and organ failure. The renowned chimpanzee, who could recognize letters of the alphabet and kanji characters, was reportedly surrounded by staff at the time of her passing. 


 

Ai, which means love in Japanese, was born in 1976 in the Guinean Forests of West Africa. Sold to the Primate Research Institute of Kyoto University (KUPRI) just over a year later, she was the first subject of the Ai project, a research program launched by Kiyoko Murofushi and Tetsuro Matsuzawa.

The aim of the project was to better understand chimpanzee cognition through computer interface experiments.

A customized keyboard linked to a computer was created for Ai and two other chimpanzees (Akira and Mari), who joined her as part of the project.

Murofushi and Matsuzawa, in collaboration with Toshio Asano, studied their memory skills, number learning abilities and perception of color. One of the early tasks for the chimpanzees was to discriminate between red, green and blue.

“At the age of five, Ai learned that Arabic numerals can represent numbers,” wrote Matsuzawa in a review essay for the website Inference in 2021.

“She was the first chimpanzee to successfully label numbers… At the age of six and a half, Ai started learning the letters of the alphabet. After some time, she was able to discriminate between all twenty-six uppercase letters.”

On the evening of October 3, 1989, Ai escaped from her cage and then released Akira and her orangutan friend Doudou after apparently using a key to open the padlocks.

Two graduate students called Matsuzawa to inform him about the situation when they saw Ai walking around campus with the key in her mouth. She had reportedly presented her bottom to the two students as a submissive signal. 

In 2010, Ai gave birth to a son, Ayumu, who is also renowned for his exceptional working memory. Away from taking cognitive tests, Ai was known to enjoy drawing and painting.

As part of the 40th anniversary celebrations of the Ai Project in 2017, esteemed primatologist Dame Jane Goodall was presented with a scarf made from one of the famous chimpanzee’s paintings.