An abandoned Caribbean colony unearthed centuries after it had been forgotten and a case of mistaken identity in the archaeological record have conspired to rewrite the history of a barrier island off the Virginia and Maryland coasts. These seemingly unrelated threads were woven together when Nicolas Delsol, PhD, a postdoctoral researcher at the Florida Museum of Natural History, set out to analyze ancient DNA recovered from cow bones found in archaeological sites. Dr. Delsol wanted to understand how cattle were domesticated in the Americas, and the genetic information preserved in centuries-old teeth held the answer. But they also held a surprise. “It was a serendipitous finding,” he said. “I was sequencing mitochondrial DNA from fossil cow teeth for my PhD and realized something was very different with one of the specimens when I analyzed the sequences.”