Geological time periods

This is the earths form of order the extinction came by.Life on Earth originated about 2 billion years ago, but there are no good fossil remains from periods earlier than the Cambrian, which began about 490 million years ago. The known geological history of Earth since the Precambrian Time is subdivided into three eras, each of which includes a number of periods.Earth's geologic epochs—time periods defined by evidence in rock layers—typically last more than three million years. We're barely 11,500 years into the current epoch, the Holocene. But a new paper argues that we've already entered a new one—the Anthropocene, or "new man," epoch.The great Precambrian expanse of time is divided into the Proterozoic, Archean, and Hadean eons in order of increasing age. The names of the eras in the Phanerozoic eon (the eon of visible life) are the Cenozoic ("recent life"), Mesozoic ("middle life") and Paleozoic ("ancient life").