By definition Dancing Fossils is a somewhat common sight you will see in warm weather retirement communities. Retirees can be seen hitting the dance floor of their favorite bar dancing to an old tune from their past . Hence they are dubbed Dancing Fossils by the locals.
eg Hey Larry, I see your Uncle Fred that just had a hip replacement is out on the dance floor with the rest of those old dancing fossils ! Larry replies ; yeah he can’t help himself, he heard Twist and Shout come on the jukebox and had to get out there