Tribes Divided by Ethnicity

Tribes Divided by Ethnicity is a game-shifting paradigm employed at the start of a competition that divides men and women into ethnic-specific tribes for a pre-determined amount of time.

Survivor: Cook Islands
Tribes were divided up into 4 ethnic groups: Hispanic-Americans (Aitutaki), Caucasians (Rarotonga), Asian-Americans (Puka Puka), and African-Americans (Manihiki). The tribes would stay this way until Day 7 when both tribes were absorbed into Aitutaki and Raro.

The contestants were put in the tribes as such:

Survivor: Fiji
It is believed that had Mellisa McNulty not withdrawn from Survivor: Fiji, Fiji would have had divisions by ethnicity similar to Cook Islands.

If Mellisa had not withdrawn, the tribal division would have been as planned:

Reception
Controversial in its execution, division by ethnicity was deemed as racial segregation by many groups and sponsors, leading to companies withdrawing their products, though some of these sponsors claim that the game format change had nothing to do with their withdrawal.

Trivia

 * In the Survivor: Cook Islands TV Guide preview, Jeff Probst stated that 80% of contestant applicants were white.