Midden Contents (image) University of Washington Caption The middens are ancient dumping sites that typically contain a mix of mollusk shells, fish and bird bones, ceramics, cloth, charcoal, maize and other plants. Credit M. Carré / Univ. of Montpellier Usage Restrictions With credit 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.