THE HUMAN SIDE OF APES
objective, puts it just underneath, gets up on it, and looking upward, makes ready to jump, but does not jump; gets down, seizes the other box, and, pulling it behind him, gallops about the room, making his usual noise, kicking against the walls and showing his uneasiness in every other possible way. He certainly did not seize the second box to put it on the first; it merely helps him to give vent to his temper. But all of a sudden his behavior changes completely; he stops making a noise, pulls his box from a distance right up to the other one, and stands it upright on it. He mounts the somewhat shaky structure, several times gets ready to jump, but again does not jump; the objective is still too high for this bad jumper. But he has achieved his task."
After having used two boxes Sultan and some of the other chimpanzees would pile three or more boxes one on the other. The apes blundered a great deal in their building operations; they had little conception of the conditions requisite to make the structure a stable one. Their performances were curiously like those of very young children dealing with similar problems. They exhibited a type of intelligence far below that of an adult human being. But it was intelligence far above that of an ordinary mammal.
Several observers have described how apes and monkeys use sticks or other implements in order to get objects that are otherwise out of reach. Miss Romanes, in describing the behavior of a Cebus monkey, says that "if a nut or any object he wishes to get hold of is beyond the reach of his chain, he puts out a stick to draw it toward him, or if that does not succeed he stands upright and throws a shawl back over his head, holding it by the two corners ; he then throws it forward with all his strength, still holding on by the corners; thus it goes out far in front of him and covers the
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