Geologic Time 1

3. Some scientists believe that the ____ extinction was caused by asteroid impacts and volcanoes.
4. The _________ explosion was the first big explosion of animal life.
7. The root word _______ comes from a Greek word for animal life
9. The root word ______ means recent or new.
10. The longest periods of geologic time
11. The _________ Era is known as the Age of Mammals.
13. The Age of Ancient Life is called the _______ era.
15. Several early civilizations created flood myths to describe their new beginnings after the _______ epoch.

1. The abbreviation for millions of years ago.
2. Within the Mesozoic era, the middle period is called the ________ period - like a park in the movies that has dinosaurs.
3. The abbreviation for thousands of years ago.
5. The "Era of Reptiles" and dinosaurs
6. Asteroid impacts and volcanoes made earth too hot for living things during the _________ eon.
8. Humans first began farming in the Fertile Crescent around the beginning of the _________ epoch, which followed the end of the Ice Age.
12. The root word "meso" as in mesozoic means ______.
14. _________ time scale is the "calendar" of events in the history of Earth.
16. The shortest periods on the Geologic Time Scale are the __________, such as the Holocene and Pleistocene.