Decades: 50s BC 40s BC 30s BC 20s BC 10s BC - 0s BC - 0s 10s 20s 30s 40s
Years: 9 BC 8 BC 7 BC 6 BC 5 BC 4 BC 3 BC 2 BC 1 BC
Significant People
... This was first proposed in the 1930s by C. B. van Neil of Stanford University, while investigating photosynthetic bacteria, many of which do not release oxygen. One ...