Zebrafish "schreckstoff" identified (IMAGE) RIKEN Caption After over 85 years, we finally know that the alarm substance that allows most fish to react to injured shoal-mates is a two-part signal: one part species-specific (conspecific social signal) and one part superorder-specific (danger signal). Credit RIKEN Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.