Requirements for the evolution of life

1. Organic molecule formation

2. Self-assembly of molecules

3. Self- replication of molecules; competition

4. Self-assembly into multi-molecular structures (cells)

5. Ability to use organic nutrients for self replication (heterotrophy)

After cell formation, the pathway to more complex life forms involved

1. Development of autotrophy (chemosynthesis or photosynthesis)

2. After oxygen formation, eukaryotic cell formation involved cooperation between anaerobic and aerobic cells (endosymbiotic origin of eukaryotic cells)

3. Formation of multicellular colonies

4. Cooperation and communication among cells for differentiation of function

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Last updated January 22, 1999.