The Xenoturbella bocki Worm (image) University of Gothenburg Caption Researchers are arguing about whether or not the Xenoturbella bocki worm is the progenitor of mankind. But new studies, involving Swedish researchers from the University of Gothenburg and the Gothenburg Natural History Museum, indicate that this is actually the case. Credit Photo: Hiroaki Nakano Usage Restrictions None 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.