The curious minds at What If discover what Earth was like 2 billion years ago, exploring early life, atmosphere, and continental formation.

New research suggests complex life on Earth emerged billions of years before previous estimates. The research also suggests ...

Oxygen is a vital and constant presence on Earth today. But that hasn't always been the case. It wasn't until around 2.3 ...

The last common ancestor of all living things did not just suddenly appear on Earth roughly 4.2 billion years ago. Some of its genes came from an even older and more mysterious source… "While the last ...

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

Geologists from St. Petersburg State University, as part of an international scientific team, have analyzed rock data from ...

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

Astronomers have announced the discovery of what appears to be an "ice cold Earth," a chilly but potentially habitable rocky ...

The discovery is just the latest to come from the asteroid sample, which dates back to the dawn of the solar system.

Aerobic respiration began hundreds of millions of years earlier than previously thought, a new study suggests.

Ancient enzymes show life’s nitrogen signal stayed unchanged for billions of years, helping scientists read early Earth.

February holds some spectacular sights in the night and morning sky. See what's happening in the skies over North Texas this ...