Science Buddies: Go and Stop? Ant Traffic Signals

Have you ever stopped to watch a trail of ants moving back and forth between a food source and their nest? Have you ever wondered how they establish their trail? You've probably read that ants use chemical signals to communicate with one another. This is a relatively simple experiment that you can do to determine whether ants use attractant signals (positive cues) or repellant signals (negative cues) or both.