1. Geologic Time Scale

2. Earth’s Age About 4.6 billion years old
1st life appeared in the oceans more than 3.6 billions years ago.
Time is separated by major events
Era = periods of time of major events

4. Paleozoic Era Formation of life started
Oxygen was formed by the process of photosynthesis
Time period where animals started to move from the oceans to land
Animals/Plants = sponges, corals, snails, squids, trilobites, and ferns

5. Real / Natural Sponge

7. FAKE / Human-made Sponge

8. Mesozoic Era Mesozoic = Middle
Age of Reptiles – Triassic, Jurassic, Cretaceous
Animals/Plants = dinosaurs, conifers, and flowering plants

9. Cenozoic Era Cenozoic = Recent Life Age of Mammals
Animals/Plants = Mammals