1. Geographic Time
8.E.6A.1Develop and use models to organize Earth’s history (including era, period, and epoch) according to the geologic time scale using evidence from rock layers

3. Geologic Time Scale
Record of the major events and diversity of life forms present in Earth’s history.
Goes from the formation of Earth to Present Day
The Time Scale is divided into Eras
Further divided into Periods
Further divided into Epochs
Subdivisions are based on large scale events in Earth’s history that are identified in the fossil record and rock layers
At the end of each era, a major mass extinction occurred
Many organisms died out, although there were other extinctions going on during each period of geologic time

4. Precambrian and Phanerozoic
First name given to the Earliest span of time in Earth’s history
4.6 Billion years – 542 million years ago
Phanerozoic divided into 3 Eras
Paleozoic- 542 mya mya
Mesozoic- 251 mya to 65.5 mya
Cenozoic mya to present

5. Paleozoic Era First Period is the Cambrian, most animal phyla appear
Early invertebrates, Developed early vertebrate fish, arachnids and insects, Later first amphibians near the Era’s end, Reptiles dominant
Early land plants
Mosses, ferns, later cone-bearing plants

6. End of Era, seed plants were common
Mass extinction that ended era caused most marine invertebrates as well as amphibians to disappear
Formation of Pangaea
Last Period was the Permian
Rapid global warming and cooling happened
95% of Marine species wiped out
70% of land animals were wiped out
Organisms could not adjust

9. Mesozoic Era Reptiles dominant DINOSAURS Present
Small mammals and birds appear
End of era, flowering plants appeared and Mammals increased
Mass extinction that ended era caused dinosaurs to become extinct
Break Up of Pangea into several large continents
Mesozoic Era

10. Cenozoic Era New Mammals emerge while other become extinct
Diversity of life increased
Flowering plants are most common
Humans are also part of the most recent period of this era
Present day Earth is in this Era
Further splitting and moving of continents to their current positions

11. Periods of the Cenozoic subdivided into further epochs due to complete fossil record available
We are in the Quaternary Period (2.588 mya- present)
Holocene Epoch 11,700 years ago to present