ERAS Phanerozoic Eon is divided into three Eras Era—"recent life" (such as mammals) Cenozoic Era—"middle life" (such as dinosaurs) Mesozoic Era—"ancient life" (such as trilobites) Paleozoic PERIODS Eras are divided into periods. Youngest Oldest
ERAS Phanerozoic Eon is divided into three Eras Cenozoic Era—"recent life" (such as mammals) Mesozoic Era—"middle life" (such as dinosaurs) Paleozoic Era—"ancient life" (such as trilobites) PERIODS Eras are divided into periods. Youngest Oldest
Ch03%20Time%20and%20Geology%20Notes.docx