1. History of Life 1 Brian O’Meara EEB464 Fall 2015 Tucson Botanical Gardens

2. Learning outcomes: Get a deep perspective on time Understand major events in earth history Generate hypotheses regarding what happens after mass extinctions

3. Big Bang 13.73 BYA

4. First stars produce more complex elements, then (some) explode

5. Borb

6. Solar system (sun, planets) form 4.6 BYA

7. Moon broken off from Earth, 4.53 BYA Ow!

8. Heavy bombardment, 4.1 - 3.8 BYA

9. Life evolves ~3.8 BYA

10. Photosynthesis evolves somewhere 3.5 - 2.8 BYAOHH OCO + = O O Sugar +

11. Great oxidation event 2.45 - 2.22 BYAOHH OCO + = O O Sugar +

12. Huronian glaciation 3.2 - 2.4 BYA

13. a long time passes Archaea+Eukaryotes and Eubacteria diverge Eukaryotes diverge from Archaea Life is still single-celled Andree Valley

16. BacteriaArchaeaEukarya Circular chromosomeYYN Histones with DNANYY FlagellaSpinning Waving UnicellularYYVaries Organelles~NNY

17. http://www.youtube.com/watch?v=9w421z4fsOU

18. a long time passes Archaea+Eukaryotes and Eubacteria diverge Eukaryotes diverge from Archaea Life is still single-celled Andree Valley

19. Ediacaran fauna 0.63 BYA = 630 MYA Wikimedia commons

20. Cambrian 542 MYA John Sibbick

21. Wikimedia commons

22. Permian-Triassic extinction 251 MYA

23. Permian-Triassic extinction 251 MYA

24. Permian-Triassic extinction 251 MYA

25. KT (Cretaceous-Tertiary) extinction 65.5 MYA Brian Franczak

26. Sun eventually becomes red giant, expands Franck et al. Causes and timing of future biosphere extinctions. Biogeosciences (2006) vol. 3 (1) pp. 85-92 Schröder and Smith. Distant future of the Sun and Earth revisited. Monthly Notices of the Royal Astronomical Society (2008) vol. 386 (1) pp. 155-163 Life evolves Multicellularity NOW Life goes extinct

27. Discussion: how might a major extinction like the one at the end of the Permian affect life?