Fossilized skeletons and shells clearly show how evolution and extinction unfolded over the past half a billion years, but a new Virginia Tech analysis extends the chart of life to nearly 2 billion years ago.

• Fossil fragments suggest Praearcturus gigas represents the largest scorpion ever discovered, perhaps one metre in length• Specimens held in the Natural History Museum collection since the 1870s have been reinterpreted using modern techniques• Giant scorpion…