Simplify the following text for a Grade 5 native English-speaking person.
Original: An ant mill is a phenomenon where a group of army ants separated from the main foraging party lose the pheromone track and begin to follow one another , forming a continuously rotating circle .
Simplified: An ant mill is a small group of army ants away from the other ants . They lose the pheromone track and begin to follow each other , making a spinning circle .