The scientific community mourns the passing of Ai, an extraordinary female chimpanzee whose groundbreaking contributions to primate cognition research revolutionized our understanding of animal intelligence. The celebrated chimpanzee, aged 49, died peacefully of natural causes and organ failure on January 9th at Kyoto University’s Center for the Evolutionary Origins of Human Behavior, surrounded by caretakers who had worked with her for decades.
Arriving at the Japanese research facility in 1977 from her native West Africa, Ai became the cornerstone of the landmark Ai Project—an ambitious scientific initiative dedicated to mapping the cognitive capabilities of chimpanzees. Her remarkable journey began at just 18 months old when researchers introduced her to a specialized computer-linked keyboard system designed to study memory formation and learning patterns.
Ai’s intellectual achievements were nothing short of extraordinary. By age five, she had mastered numerical recognition from one to six and could accurately identify colors and objects across 300 distinct samples, as documented in Dr. Tetsuro Matsuzawa’s seminal 1985 research paper. Her cognitive abilities extended beyond laboratory settings—she once demonstrated problem-solving skills by using a key to unlock her enclosure, subsequently escaping with another primate.
Beyond her scientific contributions, Ai expressed artistic creativity through drawing and painting, often choosing to engage with markers and blank paper without food-based reinforcement. Her legacy continues through her son Ayumu, born in 2000, who has himself gained scientific recognition for his exceptional memory capabilities.
The impact of Ai’s life extended to the highest echelons of primatology. In 2017, on the 40th anniversary of the Ai Project, a scarf featuring her artwork was presented to renowned anthropologist Dame Jane Goodall, symbolizing the profound intersection of scientific discovery and cross-species connection that defined Ai’s extraordinary life.