it is not unusual for some animals to play with toys. an example of this is a dolphin being trained to nudge a ball through a hoop. young chimpanzees use sticks as dolls – the social aspect is seen by the fact that young females more often use a stick this way than young male chimpanzees. they carry their chosen stick and put it in their nest. such behaviour is also seen in some adult female chimpanzees, but never after they have become mothers.