Paleontology: Earliest Life

Life on earth began more than 2 billion years ago, but only in a few places are primitive fossils clear enough to give paleontologists any faint clue to what that life was like. Most rocks that date from those early years have been deeply buried for so long and subjected to so much heat and pressure that all organic traces they once contained have been turned to shapeless specks of carbon. One notable exception is a hard, black, ancient rock found near Gunflint Lake in western Ontario, which somehow escaped this rough...