Some of Earth’s earliest microbes evolved the ability to use oxygen hundreds of millions of years before it accumulated in ...

Oxygen fills the air today, but for most of Earth’s early history it barely existed. Scientists say the atmosphere did not hold steady oxygen until about 2.

Oxygen is everywhere on Earth today. But that hasn’t always been the case. Scientists think oxygen only became a lasting part ...

Scientists studying ancient ocean fossils found that the Arabian Sea was better oxygenated 16 million years ago, even though ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. “I basically told ...

In safety-critical environments, accurate oxygen measurement is not optional - it’s essential. For manufacturers of gas ...