The Geologic Time Scale

Geologic Time Scale Match the following word to the definition Geologic Time Scale A scale used to show Earth's History Eras Geologist divide the time between Precambrian and the present into three long units called_. Precambrian The longest span of time, which covers about 88% of Earth's history. Periods Eras are subdivided into units of geologic time called_. Paleozoic Means Ancient Life-era began with early invertebrates Mesozoic Means Middle Life-know as the age of the dinosaur, reptiles are dominate, small mammals and birds appear. Cenozoic Means Recent Life-Know as the age of Man and mammals The geologic time scale is subdivided into relative ages absolute ages unconformities eras and periods Scientist developed the geologic time scale by studying_ rock layers both rock layers and index fossils index fossils environments Which major division of geologic time came first? Precambrian Paleozoic Mesozoic Cenozoic Which of the following was found in Earth's first atmosphere? carbon dioxide hydrogen oxygen ozone What were the earliest multicellular organisms? invertebrates land plants vertebrates bacteria