1. SPuD: What surprises or amazes you about the time line?
What pattern(s) do you notice in the development of life on Earth?

2. Earth forms: 4,600,000,000 years ago
4.6 bya

3. Bacteria: 3,800,000,000 years ago 3.8 bya
0.002 mm

4. First multicellular organisms: 2,100,000,000 years ago
2.1 bya

5. First Fish: 530,000,000 years ago
530 mya

6. First Land Plants (fungus): 475,000,000 years ago
475 mya

7. First Amphibian: 375,000,000
375 mya
~ 2 feet

8. First mammal: 200,000,000 years ago
200 mya
About 6 in long

9. First humans: 200,000 years ago
Homo neanderthalensis: our closest extinct human relative