To learn how cockroaches socialize, a research team from Free University of Brussels created tiny robots programmed to act like cockroaches, doused them with the proper pheromones, and set them free within crowds of cockroaches to see if they could influence behavior. While some of the robots coaxed real cockroaches to follow them into an unshaded area (away from a dark area that most normally prefer), nearly half of the robots, despite programming, fell under the “spell” of the real ones and headed for the darkness.
http://www.metropulse.com/articles/2008/18_07/weird.html
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