Opinion: Remembering Ai, a remarkably intelligent chimpanzee
Ai, a West African-born chimpanzee at Kyoto University's Primate Research Institute, displayed exceptional cognitive abilities and died of natural causes at age 49.
The evolution of rationality: How chimps process conflicting evidence
Chimpanzees revise choices when disconfirming evidence appears, demonstrating rudimentary and some reflective forms of rational decision-making, though humans possess higher social rationality.