C. Vance Haynes, University of Arizona (IMAGE) University of Arizona Caption University of Arizona anthropologist C. Vance Haynes and geophysicist Allen West look at the Black Mat Layer during a sampling excursion to the Murray Springs Clovis site in Southern Arizona. Credit Douglas J. Kennett; Courtesy of the Center for the Study of the First Americans Usage Restrictions Photo use granted only in conjunction with posting/reporting of this press release 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.