Usually , worker ants will carry food back to the colony so that the other ants and the queen can eat . Since most ants live on the ground , they use the soil surface to leave pheromone trails that can be followed by other ants . In species that forage in groups , a forager that finds food marks a trail on the way back to the colony ; this trail is followed by other ants , these ants then reinforce the trail when they head back with food to the colony .