ape99 is loosely based on the 100th monkey effect. this is a phenomenon in which a learned behavior spreads instantaneously from one group to all related groups once a critical mass is reached. in Lyall Watson’s 1979 book Lifetide, he tells of a group of scientists who observed a group of macaques that learned to wash sweet potatoes, allowing them to eat more of each potato. through observation and repetition, the younger generation of monkeys adopted this new behavior. the researchers noted tha …