As the film opens, the ants are preparing for the coming of the ravenous grasshoppers by filling a leaf with food products. For this food collection the ants stack the food following a straight line one after the other until an autumn leaf descends to the ground separating one ant from the line. This causes mass confusion and disorder. The ants learned behavior caused them to lose their self-control and allowed them to break the division of labor. Had the ants not been so set in their "assembly line" ways, they might not have had the problem they did.
Flik (the main character of the movie) holds intelligence like none of the other ants in the production. He uses his brain as opposed to learned behavior in order to try and assist the colony. His numerous inventions are advanced, yet still unrefined enough to go wrong. The other ants frown upon his differences showing ethnocentrism at it's finest. Within their own culture, Flik is looked down upon.
One could view Flik's intelligence as a mutation of the ant colony, but an even better example is that of the grasshopper's psychotic mutation known as Thumper. Thumper is used to frighten the ants even more. His intimidation factor is used against the ants so they will work harder and faster to appease the tribal grasshopper's needs.
Flik, being beyond that of his fellow ants, confronts the hierarchy of his people to make a request that he traverse to the city in search of "warrior bugs" to save the colony