Black male sex workers have been the least studied in comparison to female sex workers by researchers.  The added layers of racism, homophobia, and the HIV/AIDS epidemic has prevented sex workers of diversified backgrounds from being visible in the overall rights movement. Male escorts, gigolos, rent boys, hustlers, models, strippers, go-go dancers, masseurs, gay-for-pay, trade, pornography actors, sugar daddies, sugar babies, and fairy's have been in operation for centuries. Gender norms and laws against sodomy have kept male sex workers in the dark around the globe. During the Stonewall Riots trans activists Marsha P Johnson and Sylvia River were sex workers.