Excerpts: The six chemicals, four of which are new to science, are similar to those with which ants alert their nest-mates to trouble. One chemical attracts the ants to the wasp. When they touch it, they pick up the other chemicals that simultaneously repel them and send them into an aggressive frenzy. Avoiding the wasp, they lash out at the nearest thing - a fellow ant. The agitated ants release their own alarm chemicals, triggering more consternation and violence. In laboratory nests, the chaos lasts hours or even days.