"Instead, we have an animal that, if it just touches this molecule, bam, the aggression happens instantly," researcher Roger Hanlon, a behavioral ecologist at the Marine Biological Laboratory at Woods Hole in Massachusetts, told LiveScience. "A link between a molecule and a behavior that is that direct is not the commonest thing in science."

http://www.csmonitor.com/Science/2011/0210/Scientists-discover-how-to-make-squids-go-completely-berserk