Predators = white men
Most people seem to think the predators is a metaphor for the Muslims or the blacks or some other minority, but I got the opposite impression.
The predators were the ones who had all the power throughour history, while everyone else was the "victim". The predators also held positions of power (I mean the mayor was a lion)
The movie could be seen as a metaphor for how certain groups are prejudiced towards white people for their past (colonization etc.) The reason why predators were the minority was because in a few decades that's how it's going to be in the west. White people have among the lowest birth rates so it wouldn't be far fetched if certain minorities of today will be the majorities in the future.