Scout ants escape, but lead nest mates back to massacre
Andrea Schieber/Flickr (CC BY-NC-SA 2.0)
In a counterintuitive twist, pitcher plant traps that work only some of the time did the best job of catching huge hauls of ants for the plants to eat. A group of Nepenthes rafflesiana outperformed plants that researchers kept artificially ready to kill, catching more than twice as many ants in an experiment by taking advantage of the insects’ food foraging habits, says Ulrike Bauer of the University of Bristol.
When the funnel-shaped leaves of mature plants dry out at the nectar-coated collar, ants scouting for food can scurry safely over them without slipping into the trap. The scouts then leave trails that nest mates follow to the nectar, and when rain or dew moistens the collar again, the followers slip to their death. By “waiting” for scout ants to recruit nest mates, pitcher plants exploit the