Ai, a female chimpanzee famous for her cognitive skills has died at 49, according to the Japanese institute where she lived.
The Kyoto University's Center for the Evolutionary Origins of Human Behavior reported that Ai died on January 9 from old age and organ failure, with staff by her side.
Born in western Africa, Ai arrived in Japan in 1977 and became the namesake of the Ai Project, which focuses on the cognitive capacities of chimpanzees.
The research team discovered that Ai demonstrated the ability to use numbers and differentiate colors.
Researchers first began testing Ai's cognitive abilities when she was only 18 months old by providing her with a special keyboard linked to a computer.
At five years old, Ai had "mastered numerical naming from one to six and was able to name the number, color, and object of 300 samples," as noted by primatologist Tetsuro Matsuzawa in a scientific paper from 1985.
Ai was also known for her artistic talents, enjoying drawing and painting without needing food rewards to motivate her.
In an incident reported by Japanese media, Ai once escaped her cage using a key.
In 2000, she gave birth to a son, Ayumu, who also gained recognition for his extraordinary memory.
On the 40th anniversary of the Ai Project in 2017, a scarf created from one of Ai's paintings was presented to famed primatologist Dame Jane Goodall.
