Dot-Tailed Whiteface Dragonfly (IMAGE) University of Toronto Caption This is a dot-tailed whiteface dragonfly. Biologists at the University found that the mere presence of a predator causes enough stress to kill a dragonfly, even when the predator cannot actually get at its prey to eat it. Credit Shannon J. McCauley Usage Restrictions None License Licensed 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.