Cyanobacteria, as they still exist today, were the first organisms to carry out photosynthesis and release oxygen. Produced in primeval oceans about 2.5 billion years ago, this oxygen accumulated in ...

Earth was mostly devoid of oxygen for much of its 4.5 billion year lifetime. That is, until certain processes started to allow for the eventual buildup of oxygen up to the levels we have now (around ...

Scientists have finally cracked the mystery behind one of climate change’s strangest fingerprints: while Earth’s surface heats up, the upper atmosphere is rapidly cooling. Researchers at Columbia ...