A chimpanzee who could understand the English alphabet and more than 100 Chinese characters died, aged 49.
Ai arrived in Kyoto, Japan, as a baby, and became the center of hundreds of scholarly papers; as well as reading, she could count, identify colors, and draw and paint.
The discovery of language skills in great apes — various gorillas and chimps learned substantial vocabularies in sign language or symbols — and that of tool use across the animal kingdom have, over the years, chipped away at the idea that there is any single ingredient that makes humans unique. Instead, almost all our qualities exist in other species, albeit in less complex ways.