The main difference is that a cage dancer is a go-go dancer who performs inside a cage: "Go-Go dancers are dancers who are employed to entertain crowds at a discotheque. Go-go dancing originated in the early 1960s when women at the Peppermint Lounge in New York City began to get up on tables and dance the twist. There were many 1960s-era miniskirted clubgoers who wore what came to be called go-go boots to night clubs, so night club promoters in the mid 1960s conceived the idea of hiring them to entertain the patrons." Source and further information: http://en.wikipedia.org/wiki/Go-Go_dancing "A cage dance is a specific type of erotic dance, performed inside a cage, usually at a night club or dance hall. The activity originated in the 1960s and rose in popularity with the advent of disco music. In particular, the practice began at the Los Angeles music venue Whisky a Go Go. Though the club was billed as a discothèque, meaning only recordings with no bands, the Whisky A Go-Go opened with a live band led by Johnny Rivers and a short skirted DJ spinning records between sets from a suspended cage at the right of the stage. When the female DJ danced during Rivers' set, the audience thought it was part of the act and the concept of Go-Go dancers in cages was born. More recently, both genders practice cage dancing. Go go boys, for example, can regularly be seen in cages at night clubs frequented by homosexuals." Source and further information: http://en.wikipedia.org/wiki/Cage_dancing

About 3 decades.

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