Science·phys.org↗·3moOldest known giant rock scallop bead suggests California coastal trade began millennia earlier#Science#phys.orgSourceRead the original at phys.org0SaveShare📚Add to CollectionNext postWhen you hire film makers instead of marketers.Related postsProtecting the vulnerable Y chromosome at the beginning of developmentphys.orgAncient underwater canyons reveal clues to the world's oldest animal lifephys.orgTwo genes, two harvests: Adapting barley for double croppingphys.org