1. Patterns from the timeline of:
Life on Earth
First forms of life on earth weresimple, unicellular (one-celled) prokaryotes (no organelles) that reproduced asexually
- Eventually Photosynthetic organisms begin increasing the [O2] in earth’s atmosphere
- Prokaryotic fossils are found at an “older” point in time than Eukaryotes
- Earliest organisms were entirely water-based life

2. First forms of life on earth were simple, unicellular (one-celled) prokaryotes (no organelles) that reproduces asexually
billion years ago (bya)

3. - Eventually Photosynthetic organisms begin increasing the [O2] in earth’s atmosphere bya to 544 million years ago (mya)

4. - Earliest organisms were entirely water-based life
Oldest animal fossils: mya

5. -Earliest organisms were entirely water-based life

7. - Prokaryotic fossils are found at a “older” point in time than Eukaryotes
Eukaryotes: about 1.8 bya
Prokaryotes: about 3.8 bya

8. In summary, the history of life on earth has several patterns:
Prokaryotic life proceeded Eukaryotic life
Asexual Reproduction proceeded Sexual Reproduction
Unicellular life proceeded Multi-cellular life
Water-based life proceeded Land-based life
Anatomically
Simplistic Life
(little variation)
Anatomically
more complex life forms
(lots of variation)
…somehow gave rise to ….