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Are planets with oxygen-rich atmospheres rare?
Complex life on Earth requires oxygen. Understanding how oxygen levels have evolved on our planet can provide an insight into our own evolution and the possibility of complex life evolving elsewhere. Current theories suggest that Earth's O2 levels have risen three times over its 4.5... click to read more
Lighting a candle in the dark
More than two billion years ago, a group of microorganisms called cyanobacteria invented oxygenic photosynthesis, the process that turns light, carbon dioxide, and water into chemical energy and oxygen. Cyanobacteria are the plants of the microbial world - in fact, plants can perform photosynthesis because... click to read more