Frightened bat rays produce a chemical cue to warn other rays of danger, a well-known anti-predator strategy for bony fish that has not been documented in cartilaginous fish until now. Oregon State University researchers found the behavior of bat rays changed when they received water flow from a tan k where another bat ray was frightened by a mock predator, suggesting that a chemical disturbance cue was passed from one tank to the other. ...read more read less