The geologic time scale is split into four major eras–Precambrian, Paleozoic, Mesozoic, and Cenozoic, and are subdivided into periods. The number beside the era or period in the infotoon below shows how many years ago it began. I thought it would be fun to show it as walk through the park. This would also make for a great class project as well. For more information, see the Earth issue of Kids Discover magazine. We start at the Precambrian…
Click for a larger image. MYA=millions of years ago