Salk -- Chalasani -- Pribadi Illustration (IMAGE) Salk Institute Caption In this illustration, a <i>C. elegans</i> worm (lower right) exposed to sulfolipid chemicals from one of its natural predators, a worm called <i>P. Pacificus</i>, quickly reverses direction in a response analogous to human fear. Credit Amy Pribadi Usage Restrictions with credit and related coverage. 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.