Hymenoepimecis veranii Attacking Araneus omnicolor (image) Smithsonian Tropical Research Institute Share Print E-Mail Caption A wasp getting ready to attack a spider. Researchers think that it will then use a hormone called ecdysone to change the spider's behavior so that it spins a special kind of web. Credit Marcelo O. Gonzaga Usage Restrictions Credit: Marcelo O. Gonzaga Share Print E-Mail 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.