During the celebration, theaters called tablados are built in many places throughout the cities, especially in Montevideo. Traditionally formed by men and now starting to be open to women, the different Carnival groups (Murgas, Lubolos or Parodistas) perform a kind of popular opera at the tablados, singing and dancing songs that generally relate to the social and political situation. The 'Calls' groups, basically formed by drummers playing the tamboril, perform candombe rhythmic figures. Revelers wear their festival clothing. Each group has its own theme. Women wearing elegant, bright dresses are called vedettes and provide a sensual touch to parades.