As Nathan DeWall and I explain in Psychology, 11th Edition, “Young infants lack object permanence—the awareness that objects continue to exist even when not perceived. By 8 months, infants begin exhibiting memory for things no longer seen.”
Given the early age at which infants display object permanence by looking for a hidden toy after a several second wait do developing primates also display a recall for objects no longer seen?
Research suggests that orangutans possess object permanence. . . . a point illustrated in this hilarious 38-second YouTube video pointed out to me by a Facebook engineer who happens to be one of my former students (and also one of my children ).