Social or not, juvenile and adult animals often must rival for dominance, power in a territory and/or group, which generally allows access to food and mating. Child play may already prepare for adult dueling, as with boxing kangaroo males. In a harem system, as with some seals, only the dominant male is allowed to mate, yet often a significant percentage of 'illegitimate' offspring is protected by them unwittingly. Complex groups, like chimpanzees, may have a whole hierarchy and subtle promotion methods. Fights can be safe, like birdsong, or brutal, even incur fatal wounds, as with many horned species. teaming may help weaker individuals to break a dominant's monopoly. Some colonies, like honey ants, comprise workers and soldiers focused on a single queen, yet may raise several young queens and battle to devour all except the winner as assisted fights for the throne with breeding monopoly.