 "It shows that the jokes appeared in distinct 'waves', the first responding to the disaster with clever wordplay and the second playing with grim and troubling images associated with the event…The primary social function of disaster jokes appears to be to provide closure to an event that provoked communal grieving, by signaling that it was time to move on and pay attention to more immediate concerns".The sociologist Christie Davies has written extensively on ethnic jokes told in countries around the world.In ethnic jokes he finds that the "stupid" ethnic target in the joke is no stranger to the culture, but rather a peripheral social group (geographic, economic, cultural, linguistic) well known to the joke tellers.