The Frug was born from a dance called the Chicken which had a lateral body movement and was used as a change of pace during the twist. So as the kids grew lazier they decided to do less work, and started moving only their hips while standing still. As the hips swing from side to side they started making up arm movements for the dance.
From this came the Swim, the Monkey, the Dog, the Watusi, the Waddle or Wabble and the Jerk. Some of these dances are named with localities. What we call the Frug is often called the Surf, Big Bea and Thunderbird, with the Swim being born out of it. What we call the Watusi is also known as Wabble and Waddle. The Monkey, Dog, Bump and Jerk fall roughly into the same category.
http://www.webref.org/dance/f/frug.htm a clip
via the bbc archives How little has changed...
"So as the kids grew lazier they decided to do less work, and started moving only their hips while standing still."
