The Minds and Manners of Wild Animals: A Book of Personal Observations

The chimpanzee is not only nervous and quick in thought and in action, but it is equally so in temper. It will play with any good friend to almost any extent, but the moment it suspects malicious unfairness, or what it regards as a "mean trick," it instantly becomes angry and resentful. Once when I attempted to take from our large black-faced chimpanzee, called Soko, a small lump of rubber which I feared she might swallow, my efforts were kindly but firmly thwarted. At last, when I diverted her by small offerings of chocolate, and at the right moment sought by a strategic movement to snatch the rubber from her, the palpable unfairness of the attempt caused the animal instantly to fly into a towering passion, and seek to wreak vengeance upon me. Her lips drew far back in a savage snarl, and she denounced my perfidy by piercing cries of rage and indignation. She also did her utmost to seize and drag me forcibly within reach of her teeth, for the punishment which she felt that I deserved. A large male orang-utan named Dohong, under a similar test, revealed a very different mental attitude. He dexterously snatched a valuable watch-charm from a visitor who stood inside the railing of his cage, and fled with it to the top of his balcony. As quickly as possible I thrust my handkerchief between the bars, and waved it vigorously, to attract him. At once the animal came down to me, to secure another trophy, and before he realized his position I successfully snatched the charm from him, and restored it unharmed to its owner. Dohong seemed to regard the episode as a good joke. Without manifesting any resentment he turned a somersault on his straw, then climbed upon his trapeze and began to perform, as if nothing in particular had occurred.