"I thought, this is what the snails do on the coast of Maine when they pick up quahog clams: drill a hole in them and eat them," he says. "So I picked up the snail fossils surrounding it, and searched other places, and found more of these holes, and decided I needed to know more." He went to fossil shows and lectures, read like crazy, and continued searching for specimens. He concluded that the ancient snails probably secreted an acid on their prey, much as modern snails do, then used a tooth-like structure to bore a hole into the shell. Scholars doubted snails did so during the Ordovician period, but Felton persevered, found more samples with larger holes, and, finally, presented a paper. "Now more people believe this happened during the Ordovician time, rather than several hundred million years later."