Torben Rick, Smithsonian (IMAGE) Smithsonian Caption Torben Rick, anthropologist at the Smithsonian's National Museum of Natural History and lead author of the research, examines a 1,500-year-old oyster shell. Credit John Gibbons 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.