The earliest lifeforms, cyanobacteria, appeared around 4 billion years ago. These organisms, now known as algae, were among the first to engage in oxygenic photosynthesis.

Collision of Two Neutron Stars Billions of Years Ago Made Enough Gold and Uranium To Fill Earth's Oceans, Says Study Billions ...

About 70% of the Earth's surface is covered by marine ecosystems. Byestimates According to marine biologists, the biomass of microorganisms is about 9 ...